From e74e396204bfcb67570ba4517b08f5918e69afea Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 30 Mar 2009 19:07:44 +0900 Subject: percpu: use dynamic percpu allocator as the default percpu allocator This patch makes most !CONFIG_HAVE_SETUP_PER_CPU_AREA archs use dynamic percpu allocator. The first chunk is allocated using embedding helper and 8k is reserved for modules. This ensures that the new allocator behaves almost identically to the original allocator as long as static percpu variables are concerned, so it shouldn't introduce much breakage. s390 and alpha use custom SHIFT_PERCPU_PTR() to work around addressing range limit the addressing model imposes. Unfortunately, this breaks if the address is specified using a variable, so for now, the two archs aren't converted. The following architectures are affected by this change. * sh * arm * cris * mips * sparc(32) * blackfin * avr32 * parisc (broken, under investigation) * m32r * powerpc(32) As this change makes the dynamic allocator the default one, CONFIG_HAVE_DYNAMIC_PER_CPU_AREA is replaced with its invert - CONFIG_HAVE_LEGACY_PER_CPU_AREA, which is added to yet-to-be converted archs. These archs implement their own setup_per_cpu_areas() and the conversion is not trivial. * powerpc(64) * sparc(64) * ia64 * alpha * s390 Boot and batch alloc/free tests on x86_32 with debug code (x86_32 doesn't use default first chunk initialization). Compile tested on sparc(32), powerpc(32), arm and alpha. Kyle McMartin reported that this change breaks parisc. The problem is still under investigation and he is okay with pushing this patch forward and fixing parisc later. [ Impact: use dynamic allocator for most archs w/o custom percpu setup ] Signed-off-by: Tejun Heo Acked-by: Rusty Russell Acked-by: David S. Miller Acked-by: Benjamin Herrenschmidt Acked-by: Martin Schwidefsky Reviewed-by: Christoph Lameter Cc: Paul Mundt Cc: Russell King Cc: Mikael Starvik Cc: Ralf Baechle Cc: Bryan Wu Cc: Kyle McMartin Cc: Matthew Wilcox Cc: Grant Grundler Cc: Hirokazu Takata Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Heiko Carstens Cc: Ingo Molnar --- kernel/module.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/module.c b/kernel/module.c index 38928fcaff2b..f5934954fa99 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -364,7 +364,7 @@ EXPORT_SYMBOL_GPL(find_module); #ifdef CONFIG_SMP -#ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA +#ifndef CONFIG_HAVE_LEGACY_PER_CPU_AREA static void *percpu_modalloc(unsigned long size, unsigned long align, const char *name) @@ -389,7 +389,7 @@ static void percpu_modfree(void *freeme) free_percpu(freeme); } -#else /* ... !CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */ +#else /* ... CONFIG_HAVE_LEGACY_PER_CPU_AREA */ /* Number of blocks used and allocated. */ static unsigned int pcpu_num_used, pcpu_num_allocated; @@ -535,7 +535,7 @@ static int percpu_modinit(void) } __initcall(percpu_modinit); -#endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */ +#endif /* CONFIG_HAVE_LEGACY_PER_CPU_AREA */ static unsigned int find_pcpusec(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, -- cgit v1.2.3 From b9bf3121af348d9255f1c917830fe8c2df52efcb Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 24 Jun 2009 15:13:47 +0900 Subject: percpu: use DEFINE_PER_CPU_SHARED_ALIGNED() There are a few places where ___cacheline_aligned* is used with DEFINE_PER_CPU(). Use DEFINE_PER_CPU_SHARED_ALIGNED() instead. DEFINE_PER_CPU_SHARED_ALIGNED() applies alignment only on SMPs. While all other converted places used _in_smp variant or only get compiled for SMP, net/rds used unconditional ____cacheline_aligned. I don't see any reason these data structures should be aligned on UP and thus converted together. Signed-off-by: Tejun Heo Cc: Mike Frysinger Cc: Tony Luck Cc: Andy Grover --- arch/blackfin/mm/sram-alloc.c | 6 +++--- arch/ia64/kernel/smp.c | 3 ++- kernel/sched.c | 4 ++-- net/rds/ib_stats.c | 2 +- net/rds/iw_stats.c | 2 +- net/rds/page.c | 2 +- 6 files changed, 10 insertions(+), 9 deletions(-) (limited to 'kernel') diff --git a/arch/blackfin/mm/sram-alloc.c b/arch/blackfin/mm/sram-alloc.c index 0bc3c4ef0aad..99e4dbb1dfd1 100644 --- a/arch/blackfin/mm/sram-alloc.c +++ b/arch/blackfin/mm/sram-alloc.c @@ -42,9 +42,9 @@ #include #include "blackfin_sram.h" -static DEFINE_PER_CPU(spinlock_t, l1sram_lock) ____cacheline_aligned_in_smp; -static DEFINE_PER_CPU(spinlock_t, l1_data_sram_lock) ____cacheline_aligned_in_smp; -static DEFINE_PER_CPU(spinlock_t, l1_inst_sram_lock) ____cacheline_aligned_in_smp; +static DEFINE_PER_CPU_SHARED_ALIGNED(spinlock_t, l1sram_lock); +static DEFINE_PER_CPU_SHARED_ALIGNED(spinlock_t, l1_data_sram_lock); +static DEFINE_PER_CPU_SHARED_ALIGNED(spinlock_t, l1_inst_sram_lock); static spinlock_t l2_sram_lock ____cacheline_aligned_in_smp; /* the data structure for L1 scratchpad and DATA SRAM */ diff --git a/arch/ia64/kernel/smp.c b/arch/ia64/kernel/smp.c index 94cf78ba28fa..93ebfea43c6c 100644 --- a/arch/ia64/kernel/smp.c +++ b/arch/ia64/kernel/smp.c @@ -58,7 +58,8 @@ static struct local_tlb_flush_counts { unsigned int count; } __attribute__((__aligned__(32))) local_tlb_flush_counts[NR_CPUS]; -static DEFINE_PER_CPU(unsigned short [NR_CPUS], shadow_flush_counts) ____cacheline_aligned; +static DEFINE_PER_CPU_SHARED_ALIGNED(unsigned short [NR_CPUS], + shadow_flush_counts); #define IPI_CALL_FUNC 0 #define IPI_CPU_STOP 1 diff --git a/kernel/sched.c b/kernel/sched.c index 7c9098d186e6..34fd81d21784 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -318,12 +318,12 @@ struct task_group root_task_group; /* Default task group's sched entity on each cpu */ static DEFINE_PER_CPU(struct sched_entity, init_sched_entity); /* Default task group's cfs_rq on each cpu */ -static DEFINE_PER_CPU(struct cfs_rq, init_cfs_rq) ____cacheline_aligned_in_smp; +static DEFINE_PER_CPU_SHARED_ALIGNED(struct cfs_rq, init_cfs_rq); #endif /* CONFIG_FAIR_GROUP_SCHED */ #ifdef CONFIG_RT_GROUP_SCHED static DEFINE_PER_CPU(struct sched_rt_entity, init_sched_rt_entity); -static DEFINE_PER_CPU(struct rt_rq, init_rt_rq) ____cacheline_aligned_in_smp; +static DEFINE_PER_CPU_SHARED_ALIGNED(struct rt_rq, init_rt_rq); #endif /* CONFIG_RT_GROUP_SCHED */ #else /* !CONFIG_USER_SCHED */ #define root_task_group init_task_group diff --git a/net/rds/ib_stats.c b/net/rds/ib_stats.c index 02e3e3d50d4a..301ae51ae409 100644 --- a/net/rds/ib_stats.c +++ b/net/rds/ib_stats.c @@ -37,7 +37,7 @@ #include "rds.h" #include "ib.h" -DEFINE_PER_CPU(struct rds_ib_statistics, rds_ib_stats) ____cacheline_aligned; +DEFINE_PER_CPU_SHARED_ALIGNED(struct rds_ib_statistics, rds_ib_stats); static char *rds_ib_stat_names[] = { "ib_connect_raced", diff --git a/net/rds/iw_stats.c b/net/rds/iw_stats.c index ccc7e8f0bf0e..fafea3cc92d7 100644 --- a/net/rds/iw_stats.c +++ b/net/rds/iw_stats.c @@ -37,7 +37,7 @@ #include "rds.h" #include "iw.h" -DEFINE_PER_CPU(struct rds_iw_statistics, rds_iw_stats) ____cacheline_aligned; +DEFINE_PER_CPU_SHARED_ALIGNED(struct rds_iw_statistics, rds_iw_stats); static char *rds_iw_stat_names[] = { "iw_connect_raced", diff --git a/net/rds/page.c b/net/rds/page.c index c460743a89ad..de7bb84bcd78 100644 --- a/net/rds/page.c +++ b/net/rds/page.c @@ -39,7 +39,7 @@ struct rds_page_remainder { unsigned long r_offset; }; -DEFINE_PER_CPU(struct rds_page_remainder, rds_page_remainders) ____cacheline_aligned; +DEFINE_PER_CPU_SHARED_ALIGNED(struct rds_page_remainder, rds_page_remainders); /* * returns 0 on success or -errno on failure. -- cgit v1.2.3 From 245b2e70eabd797932adb263a65da0bab3711753 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 24 Jun 2009 15:13:48 +0900 Subject: percpu: clean up percpu variable definitions Percpu variable definition is about to be updated such that all percpu symbols including the static ones must be unique. Update percpu variable definitions accordingly. * as,cfq: rename ioc_count uniquely * cpufreq: rename cpu_dbs_info uniquely * xen: move nesting_count out of xen_evtchn_do_upcall() and rename it * mm: move ratelimits out of balance_dirty_pages_ratelimited_nr() and rename it * ipv4,6: rename cookie_scratch uniquely * x86 perf_counter: rename prev_left to pmc_prev_left, irq_entry to pmc_irq_entry and nmi_entry to pmc_nmi_entry * perf_counter: rename disable_count to perf_disable_count * ftrace: rename test_event_disable to ftrace_test_event_disable * kmemleak: rename test_pointer to kmemleak_test_pointer * mce: rename next_interval to mce_next_interval [ Impact: percpu usage cleanups, no duplicate static percpu var names ] Signed-off-by: Tejun Heo Reviewed-by: Christoph Lameter Cc: Ivan Kokshaysky Cc: Jens Axboe Cc: Dave Jones Cc: Jeremy Fitzhardinge Cc: linux-mm Cc: David S. Miller Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Li Zefan Cc: Catalin Marinas Cc: Andi Kleen --- arch/x86/kernel/cpu/mcheck/mce.c | 8 ++++---- arch/x86/kernel/cpu/perf_counter.c | 14 +++++++------- block/as-iosched.c | 10 +++++----- block/cfq-iosched.c | 10 +++++----- drivers/cpufreq/cpufreq_conservative.c | 12 ++++++------ drivers/cpufreq/cpufreq_ondemand.c | 15 ++++++++------- drivers/xen/events.c | 9 +++++---- kernel/perf_counter.c | 6 +++--- kernel/trace/trace_events.c | 6 +++--- mm/kmemleak-test.c | 6 +++--- mm/page-writeback.c | 5 +++-- net/ipv4/syncookies.c | 5 +++-- net/ipv6/syncookies.c | 5 +++-- 13 files changed, 58 insertions(+), 53 deletions(-) (limited to 'kernel') diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 284d1de968bc..cba8cd3e957b 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -1091,7 +1091,7 @@ void mce_log_therm_throt_event(__u64 status) */ static int check_interval = 5 * 60; /* 5 minutes */ -static DEFINE_PER_CPU(int, next_interval); /* in jiffies */ +static DEFINE_PER_CPU(int, mce_next_interval); /* in jiffies */ static DEFINE_PER_CPU(struct timer_list, mce_timer); static void mcheck_timer(unsigned long data) @@ -1110,7 +1110,7 @@ static void mcheck_timer(unsigned long data) * Alert userspace if needed. If we logged an MCE, reduce the * polling interval, otherwise increase the polling interval. */ - n = &__get_cpu_var(next_interval); + n = &__get_cpu_var(mce_next_interval); if (mce_notify_irq()) *n = max(*n/2, HZ/100); else @@ -1311,7 +1311,7 @@ static void mce_cpu_features(struct cpuinfo_x86 *c) static void mce_init_timer(void) { struct timer_list *t = &__get_cpu_var(mce_timer); - int *n = &__get_cpu_var(next_interval); + int *n = &__get_cpu_var(mce_next_interval); if (mce_ignore_ce) return; @@ -1914,7 +1914,7 @@ mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) case CPU_DOWN_FAILED: case CPU_DOWN_FAILED_FROZEN: t->expires = round_jiffies(jiffies + - __get_cpu_var(next_interval)); + __get_cpu_var(mce_next_interval)); add_timer_on(t, cpu); smp_call_function_single(cpu, mce_reenable_cpu, &action, 1); break; diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c index 4946288d6832..5fdf63aaaba1 100644 --- a/arch/x86/kernel/cpu/perf_counter.c +++ b/arch/x86/kernel/cpu/perf_counter.c @@ -862,7 +862,7 @@ amd_pmu_disable_counter(struct hw_perf_counter *hwc, int idx) x86_pmu_disable_counter(hwc, idx); } -static DEFINE_PER_CPU(u64 [X86_PMC_IDX_MAX], prev_left); +static DEFINE_PER_CPU(u64 [X86_PMC_IDX_MAX], pmc_prev_left); /* * Set the next IRQ period, based on the hwc->period_left value. @@ -901,7 +901,7 @@ x86_perf_counter_set_period(struct perf_counter *counter, if (left > x86_pmu.max_period) left = x86_pmu.max_period; - per_cpu(prev_left[idx], smp_processor_id()) = left; + per_cpu(pmc_prev_left[idx], smp_processor_id()) = left; /* * The hw counter starts counting from this counter offset, @@ -1089,7 +1089,7 @@ void perf_counter_print_debug(void) rdmsrl(x86_pmu.eventsel + idx, pmc_ctrl); rdmsrl(x86_pmu.perfctr + idx, pmc_count); - prev_left = per_cpu(prev_left[idx], cpu); + prev_left = per_cpu(pmc_prev_left[idx], cpu); pr_info("CPU#%d: gen-PMC%d ctrl: %016llx\n", cpu, idx, pmc_ctrl); @@ -1561,8 +1561,8 @@ void callchain_store(struct perf_callchain_entry *entry, u64 ip) entry->ip[entry->nr++] = ip; } -static DEFINE_PER_CPU(struct perf_callchain_entry, irq_entry); -static DEFINE_PER_CPU(struct perf_callchain_entry, nmi_entry); +static DEFINE_PER_CPU(struct perf_callchain_entry, pmc_irq_entry); +static DEFINE_PER_CPU(struct perf_callchain_entry, pmc_nmi_entry); static void @@ -1709,9 +1709,9 @@ struct perf_callchain_entry *perf_callchain(struct pt_regs *regs) struct perf_callchain_entry *entry; if (in_nmi()) - entry = &__get_cpu_var(nmi_entry); + entry = &__get_cpu_var(pmc_nmi_entry); else - entry = &__get_cpu_var(irq_entry); + entry = &__get_cpu_var(pmc_irq_entry); entry->nr = 0; diff --git a/block/as-iosched.c b/block/as-iosched.c index 7a12cf6ee1d3..ce8ba57c6557 100644 --- a/block/as-iosched.c +++ b/block/as-iosched.c @@ -146,7 +146,7 @@ enum arq_state { #define RQ_STATE(rq) ((enum arq_state)(rq)->elevator_private2) #define RQ_SET_STATE(rq, state) ((rq)->elevator_private2 = (void *) state) -static DEFINE_PER_CPU(unsigned long, ioc_count); +static DEFINE_PER_CPU(unsigned long, as_ioc_count); static struct completion *ioc_gone; static DEFINE_SPINLOCK(ioc_gone_lock); @@ -161,7 +161,7 @@ static void as_antic_stop(struct as_data *ad); static void free_as_io_context(struct as_io_context *aic) { kfree(aic); - elv_ioc_count_dec(ioc_count); + elv_ioc_count_dec(as_ioc_count); if (ioc_gone) { /* * AS scheduler is exiting, grab exit lock and check @@ -169,7 +169,7 @@ static void free_as_io_context(struct as_io_context *aic) * complete ioc_gone and set it back to NULL. */ spin_lock(&ioc_gone_lock); - if (ioc_gone && !elv_ioc_count_read(ioc_count)) { + if (ioc_gone && !elv_ioc_count_read(as_ioc_count)) { complete(ioc_gone); ioc_gone = NULL; } @@ -211,7 +211,7 @@ static struct as_io_context *alloc_as_io_context(void) ret->seek_total = 0; ret->seek_samples = 0; ret->seek_mean = 0; - elv_ioc_count_inc(ioc_count); + elv_ioc_count_inc(as_ioc_count); } return ret; @@ -1507,7 +1507,7 @@ static void __exit as_exit(void) ioc_gone = &all_gone; /* ioc_gone's update must be visible before reading ioc_count */ smp_wmb(); - if (elv_ioc_count_read(ioc_count)) + if (elv_ioc_count_read(as_ioc_count)) wait_for_completion(&all_gone); synchronize_rcu(); } diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 833ec18eaa63..0f1cc7d3855e 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -48,7 +48,7 @@ static int cfq_slice_idle = HZ / 125; static struct kmem_cache *cfq_pool; static struct kmem_cache *cfq_ioc_pool; -static DEFINE_PER_CPU(unsigned long, ioc_count); +static DEFINE_PER_CPU(unsigned long, cfq_ioc_count); static struct completion *ioc_gone; static DEFINE_SPINLOCK(ioc_gone_lock); @@ -1422,7 +1422,7 @@ static void cfq_cic_free_rcu(struct rcu_head *head) cic = container_of(head, struct cfq_io_context, rcu_head); kmem_cache_free(cfq_ioc_pool, cic); - elv_ioc_count_dec(ioc_count); + elv_ioc_count_dec(cfq_ioc_count); if (ioc_gone) { /* @@ -1431,7 +1431,7 @@ static void cfq_cic_free_rcu(struct rcu_head *head) * complete ioc_gone and set it back to NULL */ spin_lock(&ioc_gone_lock); - if (ioc_gone && !elv_ioc_count_read(ioc_count)) { + if (ioc_gone && !elv_ioc_count_read(cfq_ioc_count)) { complete(ioc_gone); ioc_gone = NULL; } @@ -1557,7 +1557,7 @@ cfq_alloc_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) INIT_HLIST_NODE(&cic->cic_list); cic->dtor = cfq_free_io_context; cic->exit = cfq_exit_io_context; - elv_ioc_count_inc(ioc_count); + elv_ioc_count_inc(cfq_ioc_count); } return cic; @@ -2658,7 +2658,7 @@ static void __exit cfq_exit(void) * this also protects us from entering cfq_slab_kill() with * pending RCU callbacks */ - if (elv_ioc_count_read(ioc_count)) + if (elv_ioc_count_read(cfq_ioc_count)) wait_for_completion(&all_gone); cfq_slab_kill(); } diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index 7fc58af748b4..a7ef465c83b9 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -65,7 +65,7 @@ struct cpu_dbs_info_s { int cpu; unsigned int enable:1; }; -static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info); +static DEFINE_PER_CPU(struct cpu_dbs_info_s, cs_cpu_dbs_info); static unsigned int dbs_enable; /* number of CPUs using this policy */ @@ -138,7 +138,7 @@ dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val, void *data) { struct cpufreq_freqs *freq = data; - struct cpu_dbs_info_s *this_dbs_info = &per_cpu(cpu_dbs_info, + struct cpu_dbs_info_s *this_dbs_info = &per_cpu(cs_cpu_dbs_info, freq->cpu); struct cpufreq_policy *policy; @@ -298,7 +298,7 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy, /* we need to re-evaluate prev_cpu_idle */ for_each_online_cpu(j) { struct cpu_dbs_info_s *dbs_info; - dbs_info = &per_cpu(cpu_dbs_info, j); + dbs_info = &per_cpu(cs_cpu_dbs_info, j); dbs_info->prev_cpu_idle = get_cpu_idle_time(j, &dbs_info->prev_cpu_wall); if (dbs_tuners_ins.ignore_nice) @@ -388,7 +388,7 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info) cputime64_t cur_wall_time, cur_idle_time; unsigned int idle_time, wall_time; - j_dbs_info = &per_cpu(cpu_dbs_info, j); + j_dbs_info = &per_cpu(cs_cpu_dbs_info, j); cur_idle_time = get_cpu_idle_time(j, &cur_wall_time); @@ -528,7 +528,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, unsigned int j; int rc; - this_dbs_info = &per_cpu(cpu_dbs_info, cpu); + this_dbs_info = &per_cpu(cs_cpu_dbs_info, cpu); switch (event) { case CPUFREQ_GOV_START: @@ -548,7 +548,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, for_each_cpu(j, policy->cpus) { struct cpu_dbs_info_s *j_dbs_info; - j_dbs_info = &per_cpu(cpu_dbs_info, j); + j_dbs_info = &per_cpu(cs_cpu_dbs_info, j); j_dbs_info->cur_policy = policy; j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j, diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 1911d1729353..36f292a7bd01 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -73,7 +73,7 @@ struct cpu_dbs_info_s { unsigned int enable:1, sample_type:1; }; -static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info); +static DEFINE_PER_CPU(struct cpu_dbs_info_s, od_cpu_dbs_info); static unsigned int dbs_enable; /* number of CPUs using this policy */ @@ -151,7 +151,8 @@ static unsigned int powersave_bias_target(struct cpufreq_policy *policy, unsigned int freq_hi, freq_lo; unsigned int index = 0; unsigned int jiffies_total, jiffies_hi, jiffies_lo; - struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, policy->cpu); + struct cpu_dbs_info_s *dbs_info = &per_cpu(od_cpu_dbs_info, + policy->cpu); if (!dbs_info->freq_table) { dbs_info->freq_lo = 0; @@ -196,7 +197,7 @@ static void ondemand_powersave_bias_init(void) { int i; for_each_online_cpu(i) { - struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, i); + struct cpu_dbs_info_s *dbs_info = &per_cpu(od_cpu_dbs_info, i); dbs_info->freq_table = cpufreq_frequency_get_table(i); dbs_info->freq_lo = 0; } @@ -297,7 +298,7 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy, /* we need to re-evaluate prev_cpu_idle */ for_each_online_cpu(j) { struct cpu_dbs_info_s *dbs_info; - dbs_info = &per_cpu(cpu_dbs_info, j); + dbs_info = &per_cpu(od_cpu_dbs_info, j); dbs_info->prev_cpu_idle = get_cpu_idle_time(j, &dbs_info->prev_cpu_wall); if (dbs_tuners_ins.ignore_nice) @@ -391,7 +392,7 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info) unsigned int load, load_freq; int freq_avg; - j_dbs_info = &per_cpu(cpu_dbs_info, j); + j_dbs_info = &per_cpu(od_cpu_dbs_info, j); cur_idle_time = get_cpu_idle_time(j, &cur_wall_time); @@ -548,7 +549,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, unsigned int j; int rc; - this_dbs_info = &per_cpu(cpu_dbs_info, cpu); + this_dbs_info = &per_cpu(od_cpu_dbs_info, cpu); switch (event) { case CPUFREQ_GOV_START: @@ -570,7 +571,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, for_each_cpu(j, policy->cpus) { struct cpu_dbs_info_s *j_dbs_info; - j_dbs_info = &per_cpu(cpu_dbs_info, j); + j_dbs_info = &per_cpu(od_cpu_dbs_info, j); j_dbs_info->cur_policy = policy; j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j, diff --git a/drivers/xen/events.c b/drivers/xen/events.c index ab581fa62681..7d2987e9b1bb 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -602,6 +602,8 @@ irqreturn_t xen_debug_interrupt(int irq, void *dev_id) return IRQ_HANDLED; } +static DEFINE_PER_CPU(unsigned, xed_nesting_count); + /* * Search the CPUs pending events bitmasks. For each one found, map * the event number to an irq, and feed it into do_IRQ() for @@ -617,7 +619,6 @@ void xen_evtchn_do_upcall(struct pt_regs *regs) struct pt_regs *old_regs = set_irq_regs(regs); struct shared_info *s = HYPERVISOR_shared_info; struct vcpu_info *vcpu_info = __get_cpu_var(xen_vcpu); - static DEFINE_PER_CPU(unsigned, nesting_count); unsigned count; exit_idle(); @@ -628,7 +629,7 @@ void xen_evtchn_do_upcall(struct pt_regs *regs) vcpu_info->evtchn_upcall_pending = 0; - if (__get_cpu_var(nesting_count)++) + if (__get_cpu_var(xed_nesting_count)++) goto out; #ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */ @@ -653,8 +654,8 @@ void xen_evtchn_do_upcall(struct pt_regs *regs) BUG_ON(!irqs_disabled()); - count = __get_cpu_var(nesting_count); - __get_cpu_var(nesting_count) = 0; + count = __get_cpu_var(xed_nesting_count); + __get_cpu_var(xed_nesting_count) = 0; } while(count != 1); out: diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 1a933a221ea4..1fd7a2e75754 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -98,16 +98,16 @@ hw_perf_group_sched_in(struct perf_counter *group_leader, void __weak perf_counter_print_debug(void) { } -static DEFINE_PER_CPU(int, disable_count); +static DEFINE_PER_CPU(int, perf_disable_count); void __perf_disable(void) { - __get_cpu_var(disable_count)++; + __get_cpu_var(perf_disable_count)++; } bool __perf_enable(void) { - return !--__get_cpu_var(disable_count); + return !--__get_cpu_var(perf_disable_count); } void perf_disable(void) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index aa08be69a1b6..54b1de5074b6 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1318,7 +1318,7 @@ static __init void event_trace_self_tests(void) #ifdef CONFIG_FUNCTION_TRACER -static DEFINE_PER_CPU(atomic_t, test_event_disable); +static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable); static void function_test_events_call(unsigned long ip, unsigned long parent_ip) @@ -1334,7 +1334,7 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip) pc = preempt_count(); resched = ftrace_preempt_disable(); cpu = raw_smp_processor_id(); - disabled = atomic_inc_return(&per_cpu(test_event_disable, cpu)); + disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu)); if (disabled != 1) goto out; @@ -1352,7 +1352,7 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip) trace_nowake_buffer_unlock_commit(event, flags, pc); out: - atomic_dec(&per_cpu(test_event_disable, cpu)); + atomic_dec(&per_cpu(ftrace_test_event_disable, cpu)); ftrace_preempt_enable(resched); } diff --git a/mm/kmemleak-test.c b/mm/kmemleak-test.c index d5292fc6f523..177a5169bbde 100644 --- a/mm/kmemleak-test.c +++ b/mm/kmemleak-test.c @@ -36,7 +36,7 @@ struct test_node { }; static LIST_HEAD(test_list); -static DEFINE_PER_CPU(void *, test_pointer); +static DEFINE_PER_CPU(void *, kmemleak_test_pointer); /* * Some very simple testing. This function needs to be extended for @@ -86,9 +86,9 @@ static int __init kmemleak_test_init(void) } for_each_possible_cpu(i) { - per_cpu(test_pointer, i) = kmalloc(129, GFP_KERNEL); + per_cpu(kmemleak_test_pointer, i) = kmalloc(129, GFP_KERNEL); pr_info("kmemleak: kmalloc(129) = %p\n", - per_cpu(test_pointer, i)); + per_cpu(kmemleak_test_pointer, i)); } return 0; diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 7b0dcea4935b..2c075dcf03d4 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -607,6 +607,8 @@ void set_page_dirty_balance(struct page *page, int page_mkwrite) } } +static DEFINE_PER_CPU(unsigned long, bdp_ratelimits) = 0; + /** * balance_dirty_pages_ratelimited_nr - balance dirty memory state * @mapping: address_space which was dirtied @@ -624,7 +626,6 @@ void set_page_dirty_balance(struct page *page, int page_mkwrite) void balance_dirty_pages_ratelimited_nr(struct address_space *mapping, unsigned long nr_pages_dirtied) { - static DEFINE_PER_CPU(unsigned long, ratelimits) = 0; unsigned long ratelimit; unsigned long *p; @@ -637,7 +638,7 @@ void balance_dirty_pages_ratelimited_nr(struct address_space *mapping, * tasks in balance_dirty_pages(). Period. */ preempt_disable(); - p = &__get_cpu_var(ratelimits); + p = &__get_cpu_var(bdp_ratelimits); *p += nr_pages_dirtied; if (unlikely(*p >= ratelimit)) { *p = 0; diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c index 84d90f2799bb..a6e0e077ac33 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -37,12 +37,13 @@ __initcall(init_syncookies); #define COOKIEBITS 24 /* Upper bits store count */ #define COOKIEMASK (((__u32)1 << COOKIEBITS) - 1) -static DEFINE_PER_CPU(__u32 [16 + 5 + SHA_WORKSPACE_WORDS], cookie_scratch); +static DEFINE_PER_CPU(__u32 [16 + 5 + SHA_WORKSPACE_WORDS], + ipv4_cookie_scratch); static u32 cookie_hash(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport, u32 count, int c) { - __u32 *tmp = __get_cpu_var(cookie_scratch); + __u32 *tmp = __get_cpu_var(ipv4_cookie_scratch); memcpy(tmp + 4, syncookie_secret[c], sizeof(syncookie_secret[c])); tmp[0] = (__force u32)saddr; diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index 23d0d6db0461..6b6ae913b5d4 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -74,12 +74,13 @@ static inline struct sock *get_cookie_sock(struct sock *sk, struct sk_buff *skb, return child; } -static DEFINE_PER_CPU(__u32 [16 + 5 + SHA_WORKSPACE_WORDS], cookie_scratch); +static DEFINE_PER_CPU(__u32 [16 + 5 + SHA_WORKSPACE_WORDS], + ipv6_cookie_scratch); static u32 cookie_hash(struct in6_addr *saddr, struct in6_addr *daddr, __be16 sport, __be16 dport, u32 count, int c) { - __u32 *tmp = __get_cpu_var(cookie_scratch); + __u32 *tmp = __get_cpu_var(ipv6_cookie_scratch); /* * we have 320 bits of information to hash, copy in the remaining -- cgit v1.2.3 From 951ed4d36b77ba9fe1ea08fc3c59d8bb6c9bda32 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Tue, 7 Jul 2009 11:27:28 +0200 Subject: timekeeping: optimized ktime_get[_ts] for GENERIC_TIME=y The generic ktime_get function defined in kernel/hrtimer.c is suboptimial for GENERIC_TIME=y: 0) | ktime_get() { 0) | ktime_get_ts() { 0) | getnstimeofday() { 0) | read_tod_clock() { 0) 0.601 us | } 0) 1.938 us | } 0) | set_normalized_timespec() { 0) 0.602 us | } 0) 4.375 us | } 0) 5.523 us | } Overall there are two read_seqbegin/read_seqretry loops and a lot of unnecessary struct timespec calculations. ktime_get returns a nano second value which is the sum of xtime, wall_to_monotonic and the nano second delta from the clock source. ktime_get can be optimized for GENERIC_TIME=y. The new version only calls clocksource_read: 0) | ktime_get() { 0) | read_tod_clock() { 0) 0.610 us | } 0) 1.977 us | } It uses a single read_seqbegin/readseqretry loop and just adds everthing to a nano second value. ktime_get_ts is optimized in a similar fashion. [ tglx: added WARN_ON(timekeeping_suspended) as in getnstimeofday() ] Signed-off-by: Martin Schwidefsky Acked-by: john stultz LKML-Reference: <20090707112728.3005244d@skybase> Signed-off-by: Thomas Gleixner --- kernel/hrtimer.c | 4 +++ kernel/time/timekeeping.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 73 insertions(+) (limited to 'kernel') diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 9002958a96e7..829e0664b72e 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -48,6 +48,7 @@ #include +#ifndef CONFIG_GENERIC_TIME /** * ktime_get - get the monotonic time in ktime_t format * @@ -62,6 +63,7 @@ ktime_t ktime_get(void) return timespec_to_ktime(now); } EXPORT_SYMBOL_GPL(ktime_get); +#endif /** * ktime_get_real - get the real (wall-) time in ktime_t format @@ -106,6 +108,7 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = } }; +#ifndef CONFIG_GENERIC_TIME /** * ktime_get_ts - get the monotonic clock in timespec format * @ts: pointer to timespec variable @@ -130,6 +133,7 @@ void ktime_get_ts(struct timespec *ts) ts->tv_nsec + tomono.tv_nsec); } EXPORT_SYMBOL_GPL(ktime_get_ts); +#endif /* * Get the coarse grained time at the softirq based on xtime and diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index e8c77d9c633a..7a248135c6f2 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -125,6 +125,75 @@ void getnstimeofday(struct timespec *ts) EXPORT_SYMBOL(getnstimeofday); +ktime_t ktime_get(void) +{ + cycle_t cycle_now, cycle_delta; + unsigned int seq; + s64 secs, nsecs; + + WARN_ON(timekeeping_suspended); + + do { + seq = read_seqbegin(&xtime_lock); + secs = xtime.tv_sec + wall_to_monotonic.tv_sec; + nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec; + + /* read clocksource: */ + cycle_now = clocksource_read(clock); + + /* calculate the delta since the last update_wall_time: */ + cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; + + /* convert to nanoseconds: */ + nsecs += cyc2ns(clock, cycle_delta); + + } while (read_seqretry(&xtime_lock, seq)); + /* + * Use ktime_set/ktime_add_ns to create a proper ktime on + * 32-bit architectures without CONFIG_KTIME_SCALAR. + */ + return ktime_add_ns(ktime_set(secs, 0), nsecs); +} +EXPORT_SYMBOL_GPL(ktime_get); + +/** + * ktime_get_ts - get the monotonic clock in timespec format + * @ts: pointer to timespec variable + * + * The function calculates the monotonic clock from the realtime + * clock and the wall_to_monotonic offset and stores the result + * in normalized timespec format in the variable pointed to by @ts. + */ +void ktime_get_ts(struct timespec *ts) +{ + cycle_t cycle_now, cycle_delta; + struct timespec tomono; + unsigned int seq; + s64 nsecs; + + WARN_ON(timekeeping_suspended); + + do { + seq = read_seqbegin(&xtime_lock); + *ts = xtime; + tomono = wall_to_monotonic; + + /* read clocksource: */ + cycle_now = clocksource_read(clock); + + /* calculate the delta since the last update_wall_time: */ + cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; + + /* convert to nanoseconds: */ + nsecs = cyc2ns(clock, cycle_delta); + + } while (read_seqretry(&xtime_lock, seq)); + + set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec, + ts->tv_nsec + tomono.tv_nsec + nsecs); +} +EXPORT_SYMBOL_GPL(ktime_get_ts); + /** * do_gettimeofday - Returns the time of day in a timeval * @tv: pointer to the timeval to be set -- cgit v1.2.3 From a40f262cc21fbfd781bbddcc40b16b83a75f5f34 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 7 Jul 2009 13:00:31 +0200 Subject: timekeeping: Move ktime_get() functions to timekeeping.c The ktime_get() functions for GENERIC_TIME=n are still located in hrtimer.c. Move them to time/timekeeping.c where they belong. LKML-Reference: Signed-off-by: Thomas Gleixner --- kernel/hrtimer.c | 60 ----------------------------------------------- kernel/time/timekeeping.c | 59 ++++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 57 insertions(+), 62 deletions(-) (limited to 'kernel') diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 829e0664b72e..43d151f185b6 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -48,39 +48,6 @@ #include -#ifndef CONFIG_GENERIC_TIME -/** - * ktime_get - get the monotonic time in ktime_t format - * - * returns the time in ktime_t format - */ -ktime_t ktime_get(void) -{ - struct timespec now; - - ktime_get_ts(&now); - - return timespec_to_ktime(now); -} -EXPORT_SYMBOL_GPL(ktime_get); -#endif - -/** - * ktime_get_real - get the real (wall-) time in ktime_t format - * - * returns the time in ktime_t format - */ -ktime_t ktime_get_real(void) -{ - struct timespec now; - - getnstimeofday(&now); - - return timespec_to_ktime(now); -} - -EXPORT_SYMBOL_GPL(ktime_get_real); - /* * The timer bases: * @@ -108,33 +75,6 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = } }; -#ifndef CONFIG_GENERIC_TIME -/** - * ktime_get_ts - get the monotonic clock in timespec format - * @ts: pointer to timespec variable - * - * The function calculates the monotonic clock from the realtime - * clock and the wall_to_monotonic offset and stores the result - * in normalized timespec format in the variable pointed to by @ts. - */ -void ktime_get_ts(struct timespec *ts) -{ - struct timespec tomono; - unsigned long seq; - - do { - seq = read_seqbegin(&xtime_lock); - getnstimeofday(ts); - tomono = wall_to_monotonic; - - } while (read_seqretry(&xtime_lock, seq)); - - set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec, - ts->tv_nsec + tomono.tv_nsec); -} -EXPORT_SYMBOL_GPL(ktime_get_ts); -#endif - /* * Get the coarse grained time at the softirq based on xtime and * wall_to_monotonic. diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 7a248135c6f2..02c0b2c9c674 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -290,10 +290,65 @@ static void change_clocksource(void) clock->name); */ } -#else +#else /* GENERIC_TIME */ static inline void clocksource_forward_now(void) { } static inline void change_clocksource(void) { } -#endif + +/** + * ktime_get - get the monotonic time in ktime_t format + * + * returns the time in ktime_t format + */ +ktime_t ktime_get(void) +{ + struct timespec now; + + ktime_get_ts(&now); + + return timespec_to_ktime(now); +} +EXPORT_SYMBOL_GPL(ktime_get); + +/** + * ktime_get_ts - get the monotonic clock in timespec format + * @ts: pointer to timespec variable + * + * The function calculates the monotonic clock from the realtime + * clock and the wall_to_monotonic offset and stores the result + * in normalized timespec format in the variable pointed to by @ts. + */ +void ktime_get_ts(struct timespec *ts) +{ + struct timespec tomono; + unsigned long seq; + + do { + seq = read_seqbegin(&xtime_lock); + getnstimeofday(ts); + tomono = wall_to_monotonic; + + } while (read_seqretry(&xtime_lock, seq)); + + set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec, + ts->tv_nsec + tomono.tv_nsec); +} +EXPORT_SYMBOL_GPL(ktime_get_ts); +#endif /* !GENERIC_TIME */ + +/** + * ktime_get_real - get the real (wall-) time in ktime_t format + * + * returns the time in ktime_t format + */ +ktime_t ktime_get_real(void) +{ + struct timespec now; + + getnstimeofday(&now); + + return timespec_to_ktime(now); +} +EXPORT_SYMBOL_GPL(ktime_get_real); /** * getrawmonotonic - Returns the raw monotonic time in a timespec -- cgit v1.2.3 From 86886e55b273f565935491816c7c96b82469d4f8 Mon Sep 17 00:00:00 2001 From: Joseph Cihula Date: Tue, 30 Jun 2009 19:31:07 -0700 Subject: x86, intel_txt: Intel TXT Sx shutdown support Support for graceful handling of sleep states (S3/S4/S5) after an Intel(R) TXT launch. Without this patch, attempting to place the system in one of the ACPI sleep states (S3/S4/S5) will cause the TXT hardware to treat this as an attack and will cause a system reset, with memory locked. Not only may the subsequent memory scrub take some time, but the platform will be unable to enter the requested power state. This patch calls back into the tboot so that it may properly and securely clean up system state and clear the secrets-in-memory flag, after which it will place the system into the requested sleep state using ACPI information passed by the kernel. arch/x86/kernel/smpboot.c | 2 ++ drivers/acpi/acpica/hwsleep.c | 3 +++ kernel/cpu.c | 7 ++++++- 3 files changed, 11 insertions(+), 1 deletion(-) Signed-off-by: Joseph Cihula Signed-off-by: Shane Wang Signed-off-by: H. Peter Anvin --- arch/x86/kernel/smpboot.c | 2 ++ drivers/acpi/acpica/hwsleep.c | 3 +++ kernel/cpu.c | 7 ++++++- 3 files changed, 11 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 2fecda69ee64..61cc40887c48 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -62,6 +62,7 @@ #include #include #include +#include #include #include @@ -1317,6 +1318,7 @@ void play_dead_common(void) void native_play_dead(void) { play_dead_common(); + tboot_shutdown(TB_SHUTDOWN_WFS); wbinvd_halt(); } diff --git a/drivers/acpi/acpica/hwsleep.c b/drivers/acpi/acpica/hwsleep.c index db307a356f08..8c01dd3724e0 100644 --- a/drivers/acpi/acpica/hwsleep.c +++ b/drivers/acpi/acpica/hwsleep.c @@ -45,6 +45,7 @@ #include #include "accommon.h" #include "actables.h" +#include #define _COMPONENT ACPI_HARDWARE ACPI_MODULE_NAME("hwsleep") @@ -342,6 +343,8 @@ acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state) ACPI_FLUSH_CPU_CACHE(); + tboot_sleep(sleep_state, pm1a_control, pm1b_control); + /* Write #2: Write both SLP_TYP + SLP_EN */ status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control); diff --git a/kernel/cpu.c b/kernel/cpu.c index 8ce10043e4ac..ff071e022a85 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -14,6 +14,7 @@ #include #include #include +#include #ifdef CONFIG_SMP /* Serializes the updates to cpu_online_mask, cpu_present_mask */ @@ -376,7 +377,7 @@ static cpumask_var_t frozen_cpus; int disable_nonboot_cpus(void) { - int cpu, first_cpu, error; + int cpu, first_cpu, error, num_cpus = 0; error = stop_machine_create(); if (error) @@ -391,6 +392,7 @@ int disable_nonboot_cpus(void) for_each_online_cpu(cpu) { if (cpu == first_cpu) continue; + num_cpus++; error = _cpu_down(cpu, 1); if (!error) { cpumask_set_cpu(cpu, frozen_cpus); @@ -401,6 +403,9 @@ int disable_nonboot_cpus(void) break; } } + /* ensure all CPUs have gone into wait-for-SIPI */ + error |= tboot_wait_for_aps(num_cpus); + if (!error) { BUG_ON(num_online_cpus() > 1); /* Make sure the CPUs won't be enabled by someone else */ -- cgit v1.2.3 From fbd90375d7531927d312766b548376d909811b4d Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 22 Jul 2009 13:40:14 +0200 Subject: hrtimer: Remove cb_entry from struct hrtimer It's unused, remove it. Signed-off-by: Peter Zijlstra Signed-off-by: Thomas Gleixner LKML-Reference: --- include/linux/hrtimer.h | 2 -- kernel/hrtimer.c | 1 - 2 files changed, 3 deletions(-) (limited to 'kernel') diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 54648e625efd..40e7d54fc424 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -91,7 +91,6 @@ enum hrtimer_restart { * @function: timer expiry callback function * @base: pointer to the timer base (per cpu and per clock) * @state: state information (See bit values above) - * @cb_entry: list head to enqueue an expired timer into the callback list * @start_site: timer statistics field to store the site where the timer * was started * @start_comm: timer statistics field to store the name of the process which @@ -108,7 +107,6 @@ struct hrtimer { enum hrtimer_restart (*function)(struct hrtimer *); struct hrtimer_clock_base *base; unsigned long state; - struct list_head cb_entry; #ifdef CONFIG_TIMER_STATS int start_pid; void *start_site; diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 43d151f185b6..052a0f53e4eb 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -1092,7 +1092,6 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, clock_id = CLOCK_MONOTONIC; timer->base = &cpu_base->clock_base[clock_id]; - INIT_LIST_HEAD(&timer->cb_entry); hrtimer_init_timer_hres(timer); #ifdef CONFIG_TIMER_STATS -- cgit v1.2.3 From 42c4ab41a176ee784c0f28c0b29025a8fc34f05a Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Wed, 29 Jul 2009 12:15:26 +0200 Subject: itimers: Merge ITIMER_VIRT and ITIMER_PROF Both cpu itimers have same data flow in the few places, this patch make unification of code related with VIRT and PROF itimers. Signed-off-by: Stanislaw Gruszka Acked-by: Peter Zijlstra Acked-by: Thomas Gleixner Cc: Oleg Nesterov Cc: Andrew Morton Cc: Paul Mackerras Cc: Benjamin Herrenschmidt LKML-Reference: <1248862529-6063-2-git-send-email-sgruszka@redhat.com> Signed-off-by: Ingo Molnar --- include/linux/sched.h | 14 ++++- kernel/fork.c | 9 +-- kernel/itimer.c | 146 +++++++++++++++++++++------------------------- kernel/posix-cpu-timers.c | 98 +++++++++++++++---------------- 4 files changed, 130 insertions(+), 137 deletions(-) (limited to 'kernel') diff --git a/include/linux/sched.h b/include/linux/sched.h index 3ab08e4bb6b8..3b3efaddd953 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -470,6 +470,11 @@ struct pacct_struct { unsigned long ac_minflt, ac_majflt; }; +struct cpu_itimer { + cputime_t expires; + cputime_t incr; +}; + /** * struct task_cputime - collected CPU time counts * @utime: time spent in user mode, in &cputime_t units @@ -564,9 +569,12 @@ struct signal_struct { struct pid *leader_pid; ktime_t it_real_incr; - /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */ - cputime_t it_prof_expires, it_virt_expires; - cputime_t it_prof_incr, it_virt_incr; + /* + * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use + * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these + * values are defined to 0 and 1 respectively + */ + struct cpu_itimer it[2]; /* * Thread group totals for process CPU timers. diff --git a/kernel/fork.c b/kernel/fork.c index 29b532e718f7..893ab0bf5e39 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -62,6 +62,7 @@ #include #include #include +#include #include #include @@ -790,10 +791,10 @@ static void posix_cpu_timers_init_group(struct signal_struct *sig) thread_group_cputime_init(sig); /* Expiration times and increments. */ - sig->it_virt_expires = cputime_zero; - sig->it_virt_incr = cputime_zero; - sig->it_prof_expires = cputime_zero; - sig->it_prof_incr = cputime_zero; + sig->it[CPUCLOCK_PROF].expires = cputime_zero; + sig->it[CPUCLOCK_PROF].incr = cputime_zero; + sig->it[CPUCLOCK_VIRT].expires = cputime_zero; + sig->it[CPUCLOCK_VIRT].incr = cputime_zero; /* Cached expiration times. */ sig->cputime_expires.prof_exp = cputime_zero; diff --git a/kernel/itimer.c b/kernel/itimer.c index 58762f7077ec..852c88ddd1f0 100644 --- a/kernel/itimer.c +++ b/kernel/itimer.c @@ -41,10 +41,43 @@ static struct timeval itimer_get_remtime(struct hrtimer *timer) return ktime_to_timeval(rem); } +static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, + struct itimerval *value) +{ + cputime_t cval, cinterval; + struct cpu_itimer *it = &tsk->signal->it[clock_id]; + + spin_lock_irq(&tsk->sighand->siglock); + + cval = it->expires; + cinterval = it->incr; + if (!cputime_eq(cval, cputime_zero)) { + struct task_cputime cputime; + cputime_t t; + + thread_group_cputimer(tsk, &cputime); + if (clock_id == CPUCLOCK_PROF) + t = cputime_add(cputime.utime, cputime.stime); + else + /* CPUCLOCK_VIRT */ + t = cputime.utime; + + if (cputime_le(cval, t)) + /* about to fire */ + cval = jiffies_to_cputime(1); + else + cval = cputime_sub(cval, t); + } + + spin_unlock_irq(&tsk->sighand->siglock); + + cputime_to_timeval(cval, &value->it_value); + cputime_to_timeval(cinterval, &value->it_interval); +} + int do_getitimer(int which, struct itimerval *value) { struct task_struct *tsk = current; - cputime_t cinterval, cval; switch (which) { case ITIMER_REAL: @@ -55,44 +88,10 @@ int do_getitimer(int which, struct itimerval *value) spin_unlock_irq(&tsk->sighand->siglock); break; case ITIMER_VIRTUAL: - spin_lock_irq(&tsk->sighand->siglock); - cval = tsk->signal->it_virt_expires; - cinterval = tsk->signal->it_virt_incr; - if (!cputime_eq(cval, cputime_zero)) { - struct task_cputime cputime; - cputime_t utime; - - thread_group_cputimer(tsk, &cputime); - utime = cputime.utime; - if (cputime_le(cval, utime)) { /* about to fire */ - cval = jiffies_to_cputime(1); - } else { - cval = cputime_sub(cval, utime); - } - } - spin_unlock_irq(&tsk->sighand->siglock); - cputime_to_timeval(cval, &value->it_value); - cputime_to_timeval(cinterval, &value->it_interval); + get_cpu_itimer(tsk, CPUCLOCK_VIRT, value); break; case ITIMER_PROF: - spin_lock_irq(&tsk->sighand->siglock); - cval = tsk->signal->it_prof_expires; - cinterval = tsk->signal->it_prof_incr; - if (!cputime_eq(cval, cputime_zero)) { - struct task_cputime times; - cputime_t ptime; - - thread_group_cputimer(tsk, ×); - ptime = cputime_add(times.utime, times.stime); - if (cputime_le(cval, ptime)) { /* about to fire */ - cval = jiffies_to_cputime(1); - } else { - cval = cputime_sub(cval, ptime); - } - } - spin_unlock_irq(&tsk->sighand->siglock); - cputime_to_timeval(cval, &value->it_value); - cputime_to_timeval(cinterval, &value->it_interval); + get_cpu_itimer(tsk, CPUCLOCK_PROF, value); break; default: return(-EINVAL); @@ -128,6 +127,36 @@ enum hrtimer_restart it_real_fn(struct hrtimer *timer) return HRTIMER_NORESTART; } +static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, + struct itimerval *value, struct itimerval *ovalue) +{ + cputime_t cval, cinterval, nval, ninterval; + struct cpu_itimer *it = &tsk->signal->it[clock_id]; + + nval = timeval_to_cputime(&value->it_value); + ninterval = timeval_to_cputime(&value->it_interval); + + spin_lock_irq(&tsk->sighand->siglock); + + cval = it->expires; + cinterval = it->incr; + if (!cputime_eq(cval, cputime_zero) || + !cputime_eq(nval, cputime_zero)) { + if (cputime_gt(nval, cputime_zero)) + nval = cputime_add(nval, jiffies_to_cputime(1)); + set_process_cpu_timer(tsk, clock_id, &nval, &cval); + } + it->expires = nval; + it->incr = ninterval; + + spin_unlock_irq(&tsk->sighand->siglock); + + if (ovalue) { + cputime_to_timeval(cval, &ovalue->it_value); + cputime_to_timeval(cinterval, &ovalue->it_interval); + } +} + /* * Returns true if the timeval is in canonical form */ @@ -139,7 +168,6 @@ int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue) struct task_struct *tsk = current; struct hrtimer *timer; ktime_t expires; - cputime_t cval, cinterval, nval, ninterval; /* * Validate the timevals in value. @@ -174,48 +202,10 @@ again: spin_unlock_irq(&tsk->sighand->siglock); break; case ITIMER_VIRTUAL: - nval = timeval_to_cputime(&value->it_value); - ninterval = timeval_to_cputime(&value->it_interval); - spin_lock_irq(&tsk->sighand->siglock); - cval = tsk->signal->it_virt_expires; - cinterval = tsk->signal->it_virt_incr; - if (!cputime_eq(cval, cputime_zero) || - !cputime_eq(nval, cputime_zero)) { - if (cputime_gt(nval, cputime_zero)) - nval = cputime_add(nval, - jiffies_to_cputime(1)); - set_process_cpu_timer(tsk, CPUCLOCK_VIRT, - &nval, &cval); - } - tsk->signal->it_virt_expires = nval; - tsk->signal->it_virt_incr = ninterval; - spin_unlock_irq(&tsk->sighand->siglock); - if (ovalue) { - cputime_to_timeval(cval, &ovalue->it_value); - cputime_to_timeval(cinterval, &ovalue->it_interval); - } + set_cpu_itimer(tsk, CPUCLOCK_VIRT, value, ovalue); break; case ITIMER_PROF: - nval = timeval_to_cputime(&value->it_value); - ninterval = timeval_to_cputime(&value->it_interval); - spin_lock_irq(&tsk->sighand->siglock); - cval = tsk->signal->it_prof_expires; - cinterval = tsk->signal->it_prof_incr; - if (!cputime_eq(cval, cputime_zero) || - !cputime_eq(nval, cputime_zero)) { - if (cputime_gt(nval, cputime_zero)) - nval = cputime_add(nval, - jiffies_to_cputime(1)); - set_process_cpu_timer(tsk, CPUCLOCK_PROF, - &nval, &cval); - } - tsk->signal->it_prof_expires = nval; - tsk->signal->it_prof_incr = ninterval; - spin_unlock_irq(&tsk->sighand->siglock); - if (ovalue) { - cputime_to_timeval(cval, &ovalue->it_value); - cputime_to_timeval(cinterval, &ovalue->it_interval); - } + set_cpu_itimer(tsk, CPUCLOCK_PROF, value, ovalue); break; default: return -EINVAL; diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index bece7c0b67b2..9b2d5e4dc8c4 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -14,11 +14,11 @@ */ void update_rlimit_cpu(unsigned long rlim_new) { - cputime_t cputime; + cputime_t cputime = secs_to_cputime(rlim_new); + struct signal_struct *const sig = current->signal; - cputime = secs_to_cputime(rlim_new); - if (cputime_eq(current->signal->it_prof_expires, cputime_zero) || - cputime_gt(current->signal->it_prof_expires, cputime)) { + if (cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) || + cputime_gt(sig->it[CPUCLOCK_PROF].expires, cputime)) { spin_lock_irq(¤t->sighand->siglock); set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL); spin_unlock_irq(¤t->sighand->siglock); @@ -613,6 +613,9 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now) break; } } else { + struct signal_struct *const sig = p->signal; + union cpu_time_count *exp = &timer->it.cpu.expires; + /* * For a process timer, set the cached expiration time. */ @@ -620,30 +623,27 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now) default: BUG(); case CPUCLOCK_VIRT: - if (!cputime_eq(p->signal->it_virt_expires, + if (!cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) && - cputime_lt(p->signal->it_virt_expires, - timer->it.cpu.expires.cpu)) + cputime_lt(sig->it[CPUCLOCK_VIRT].expires, + exp->cpu)) break; - p->signal->cputime_expires.virt_exp = - timer->it.cpu.expires.cpu; + sig->cputime_expires.virt_exp = exp->cpu; break; case CPUCLOCK_PROF: - if (!cputime_eq(p->signal->it_prof_expires, + if (!cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) && - cputime_lt(p->signal->it_prof_expires, - timer->it.cpu.expires.cpu)) + cputime_lt(sig->it[CPUCLOCK_PROF].expires, + exp->cpu)) break; - i = p->signal->rlim[RLIMIT_CPU].rlim_cur; + i = sig->rlim[RLIMIT_CPU].rlim_cur; if (i != RLIM_INFINITY && - i <= cputime_to_secs(timer->it.cpu.expires.cpu)) + i <= cputime_to_secs(exp->cpu)) break; - p->signal->cputime_expires.prof_exp = - timer->it.cpu.expires.cpu; + sig->cputime_expires.prof_exp = exp->cpu; break; case CPUCLOCK_SCHED: - p->signal->cputime_expires.sched_exp = - timer->it.cpu.expires.sched; + sig->cputime_expires.sched_exp = exp->sched; break; } } @@ -1070,6 +1070,27 @@ static void stop_process_timers(struct task_struct *tsk) spin_unlock_irqrestore(&cputimer->lock, flags); } +static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, + cputime_t *expires, cputime_t cur_time, int signo) +{ + if (cputime_eq(it->expires, cputime_zero)) + return; + + if (cputime_ge(cur_time, it->expires)) { + it->expires = it->incr; + if (!cputime_eq(it->expires, cputime_zero)) + it->expires = cputime_add(it->expires, cur_time); + + __group_send_sig_info(signo, SEND_SIG_PRIV, tsk); + } + + if (!cputime_eq(it->expires, cputime_zero) && + (cputime_eq(*expires, cputime_zero) || + cputime_lt(it->expires, *expires))) { + *expires = it->expires; + } +} + /* * Check for any per-thread CPU timers that have fired and move them * off the tsk->*_timers list onto the firing list. Per-thread timers @@ -1089,10 +1110,10 @@ static void check_process_timers(struct task_struct *tsk, * Don't sample the current process CPU clocks if there are no timers. */ if (list_empty(&timers[CPUCLOCK_PROF]) && - cputime_eq(sig->it_prof_expires, cputime_zero) && + cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) && sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY && list_empty(&timers[CPUCLOCK_VIRT]) && - cputime_eq(sig->it_virt_expires, cputime_zero) && + cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) && list_empty(&timers[CPUCLOCK_SCHED])) { stop_process_timers(tsk); return; @@ -1152,38 +1173,11 @@ static void check_process_timers(struct task_struct *tsk, /* * Check for the special case process timers. */ - if (!cputime_eq(sig->it_prof_expires, cputime_zero)) { - if (cputime_ge(ptime, sig->it_prof_expires)) { - /* ITIMER_PROF fires and reloads. */ - sig->it_prof_expires = sig->it_prof_incr; - if (!cputime_eq(sig->it_prof_expires, cputime_zero)) { - sig->it_prof_expires = cputime_add( - sig->it_prof_expires, ptime); - } - __group_send_sig_info(SIGPROF, SEND_SIG_PRIV, tsk); - } - if (!cputime_eq(sig->it_prof_expires, cputime_zero) && - (cputime_eq(prof_expires, cputime_zero) || - cputime_lt(sig->it_prof_expires, prof_expires))) { - prof_expires = sig->it_prof_expires; - } - } - if (!cputime_eq(sig->it_virt_expires, cputime_zero)) { - if (cputime_ge(utime, sig->it_virt_expires)) { - /* ITIMER_VIRTUAL fires and reloads. */ - sig->it_virt_expires = sig->it_virt_incr; - if (!cputime_eq(sig->it_virt_expires, cputime_zero)) { - sig->it_virt_expires = cputime_add( - sig->it_virt_expires, utime); - } - __group_send_sig_info(SIGVTALRM, SEND_SIG_PRIV, tsk); - } - if (!cputime_eq(sig->it_virt_expires, cputime_zero) && - (cputime_eq(virt_expires, cputime_zero) || - cputime_lt(sig->it_virt_expires, virt_expires))) { - virt_expires = sig->it_virt_expires; - } - } + check_cpu_itimer(tsk, &sig->it[CPUCLOCK_PROF], &prof_expires, ptime, + SIGPROF); + check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime, + SIGVTALRM); + if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { unsigned long psecs = cputime_to_secs(ptime); cputime_t x; -- cgit v1.2.3 From 8356b5f9c424e5831715abbce747197c30d1fd71 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Wed, 29 Jul 2009 12:15:27 +0200 Subject: itimers: Fix periodic tics precision Measure ITIMER_PROF and ITIMER_VIRT timers interval error between real ticks and requested by user. Take it into account when scheduling next tick. This patch introduce possibility where time between two consecutive tics is smaller then requested interval, it preserve however dependency that n tick is generated not earlier than n*interval time - counting from the beginning of periodic signal generation. Signed-off-by: Stanislaw Gruszka Acked-by: Peter Zijlstra Acked-by: Thomas Gleixner Cc: Oleg Nesterov Cc: Andrew Morton Cc: Paul Mackerras Cc: Benjamin Herrenschmidt LKML-Reference: <1248862529-6063-3-git-send-email-sgruszka@redhat.com> Signed-off-by: Ingo Molnar --- include/linux/sched.h | 2 ++ kernel/itimer.c | 24 +++++++++++++++++++++--- kernel/posix-cpu-timers.c | 20 +++++++++++++++++--- 3 files changed, 40 insertions(+), 6 deletions(-) (limited to 'kernel') diff --git a/include/linux/sched.h b/include/linux/sched.h index 3b3efaddd953..a069e65e8bb7 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -473,6 +473,8 @@ struct pacct_struct { struct cpu_itimer { cputime_t expires; cputime_t incr; + u32 error; + u32 incr_error; }; /** diff --git a/kernel/itimer.c b/kernel/itimer.c index 852c88ddd1f0..21adff7b2a17 100644 --- a/kernel/itimer.c +++ b/kernel/itimer.c @@ -42,7 +42,7 @@ static struct timeval itimer_get_remtime(struct hrtimer *timer) } static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, - struct itimerval *value) + struct itimerval *const value) { cputime_t cval, cinterval; struct cpu_itimer *it = &tsk->signal->it[clock_id]; @@ -127,14 +127,32 @@ enum hrtimer_restart it_real_fn(struct hrtimer *timer) return HRTIMER_NORESTART; } +static inline u32 cputime_sub_ns(cputime_t ct, s64 real_ns) +{ + struct timespec ts; + s64 cpu_ns; + + cputime_to_timespec(ct, &ts); + cpu_ns = timespec_to_ns(&ts); + + return (cpu_ns <= real_ns) ? 0 : cpu_ns - real_ns; +} + static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, - struct itimerval *value, struct itimerval *ovalue) + const struct itimerval *const value, + struct itimerval *const ovalue) { - cputime_t cval, cinterval, nval, ninterval; + cputime_t cval, nval, cinterval, ninterval; + s64 ns_ninterval, ns_nval; struct cpu_itimer *it = &tsk->signal->it[clock_id]; nval = timeval_to_cputime(&value->it_value); + ns_nval = timeval_to_ns(&value->it_value); ninterval = timeval_to_cputime(&value->it_interval); + ns_ninterval = timeval_to_ns(&value->it_interval); + + it->incr_error = cputime_sub_ns(ninterval, ns_ninterval); + it->error = cputime_sub_ns(nval, ns_nval); spin_lock_irq(&tsk->sighand->siglock); diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index 9b2d5e4dc8c4..b60d644ea4b3 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -1070,6 +1070,8 @@ static void stop_process_timers(struct task_struct *tsk) spin_unlock_irqrestore(&cputimer->lock, flags); } +static u32 onecputick; + static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, cputime_t *expires, cputime_t cur_time, int signo) { @@ -1077,9 +1079,16 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, return; if (cputime_ge(cur_time, it->expires)) { - it->expires = it->incr; - if (!cputime_eq(it->expires, cputime_zero)) - it->expires = cputime_add(it->expires, cur_time); + if (!cputime_eq(it->incr, cputime_zero)) { + it->expires = cputime_add(it->expires, it->incr); + it->error += it->incr_error; + if (it->error >= onecputick) { + it->expires = cputime_sub(it->expires, + jiffies_to_cputime(1)); + it->error -= onecputick; + } + } else + it->expires = cputime_zero; __group_send_sig_info(signo, SEND_SIG_PRIV, tsk); } @@ -1696,10 +1705,15 @@ static __init int init_posix_cpu_timers(void) .nsleep = thread_cpu_nsleep, .nsleep_restart = thread_cpu_nsleep_restart, }; + struct timespec ts; register_posix_clock(CLOCK_PROCESS_CPUTIME_ID, &process); register_posix_clock(CLOCK_THREAD_CPUTIME_ID, &thread); + cputime_to_timespec(jiffies_to_cputime(1), &ts); + onecputick = ts.tv_nsec; + WARN_ON(ts.tv_sec != 0); + return 0; } __initcall(init_posix_cpu_timers); -- cgit v1.2.3 From d1e3b6d195770bd422e3229b88edfc154b6a27dd Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Wed, 29 Jul 2009 12:15:28 +0200 Subject: itimers: Simplify arm_timer() code a bit Don't update values in expiration cache when new ones are equal. Add expire_le() and expire_gt() helpers to simplify the code. Signed-off-by: Stanislaw Gruszka Acked-by: Peter Zijlstra Acked-by: Thomas Gleixner Cc: Oleg Nesterov Cc: Andrew Morton Cc: Paul Mackerras Cc: Benjamin Herrenschmidt LKML-Reference: <1248862529-6063-4-git-send-email-sgruszka@redhat.com> Signed-off-by: Ingo Molnar --- kernel/posix-cpu-timers.c | 44 +++++++++++++++++++++++--------------------- 1 file changed, 23 insertions(+), 21 deletions(-) (limited to 'kernel') diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index b60d644ea4b3..69c92374355f 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -541,6 +541,17 @@ static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now) now); } +static inline int expires_gt(cputime_t expires, cputime_t new_exp) +{ + return cputime_eq(expires, cputime_zero) || + cputime_gt(expires, new_exp); +} + +static inline int expires_le(cputime_t expires, cputime_t new_exp) +{ + return !cputime_eq(expires, cputime_zero) && + cputime_le(expires, new_exp); +} /* * Insert the timer on the appropriate list before any timers that * expire later. This must be called with the tasklist_lock held @@ -585,31 +596,26 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now) */ if (CPUCLOCK_PERTHREAD(timer->it_clock)) { + union cpu_time_count *exp = &nt->expires; + switch (CPUCLOCK_WHICH(timer->it_clock)) { default: BUG(); case CPUCLOCK_PROF: - if (cputime_eq(p->cputime_expires.prof_exp, - cputime_zero) || - cputime_gt(p->cputime_expires.prof_exp, - nt->expires.cpu)) - p->cputime_expires.prof_exp = - nt->expires.cpu; + if (expires_gt(p->cputime_expires.prof_exp, + exp->cpu)) + p->cputime_expires.prof_exp = exp->cpu; break; case CPUCLOCK_VIRT: - if (cputime_eq(p->cputime_expires.virt_exp, - cputime_zero) || - cputime_gt(p->cputime_expires.virt_exp, - nt->expires.cpu)) - p->cputime_expires.virt_exp = - nt->expires.cpu; + if (expires_gt(p->cputime_expires.virt_exp, + exp->cpu)) + p->cputime_expires.virt_exp = exp->cpu; break; case CPUCLOCK_SCHED: if (p->cputime_expires.sched_exp == 0 || - p->cputime_expires.sched_exp > - nt->expires.sched) + p->cputime_expires.sched_exp > exp->sched) p->cputime_expires.sched_exp = - nt->expires.sched; + exp->sched; break; } } else { @@ -623,17 +629,13 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now) default: BUG(); case CPUCLOCK_VIRT: - if (!cputime_eq(sig->it[CPUCLOCK_VIRT].expires, - cputime_zero) && - cputime_lt(sig->it[CPUCLOCK_VIRT].expires, + if (expires_le(sig->it[CPUCLOCK_VIRT].expires, exp->cpu)) break; sig->cputime_expires.virt_exp = exp->cpu; break; case CPUCLOCK_PROF: - if (!cputime_eq(sig->it[CPUCLOCK_PROF].expires, - cputime_zero) && - cputime_lt(sig->it[CPUCLOCK_PROF].expires, + if (expires_le(sig->it[CPUCLOCK_PROF].expires, exp->cpu)) break; i = sig->rlim[RLIMIT_CPU].rlim_cur; -- cgit v1.2.3 From a42548a18866e87092db93b771e6c5b060d78401 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Wed, 29 Jul 2009 12:15:29 +0200 Subject: cputime: Optimize jiffies_to_cputime(1) For powerpc with CONFIG_VIRT_CPU_ACCOUNTING jiffies_to_cputime(1) is not compile time constant and run time calculations are quite expensive. To optimize we use precomputed value. For all other architectures is is preprocessor definition. Signed-off-by: Stanislaw Gruszka Acked-by: Peter Zijlstra Acked-by: Thomas Gleixner Cc: Oleg Nesterov Cc: Andrew Morton Cc: Paul Mackerras Cc: Benjamin Herrenschmidt LKML-Reference: <1248862529-6063-5-git-send-email-sgruszka@redhat.com> Signed-off-by: Ingo Molnar --- arch/ia64/include/asm/cputime.h | 1 + arch/powerpc/include/asm/cputime.h | 13 +++++++++++++ arch/powerpc/kernel/time.c | 4 ++++ arch/s390/include/asm/cputime.h | 1 + include/asm-generic/cputime.h | 1 + kernel/itimer.c | 4 ++-- kernel/posix-cpu-timers.c | 6 +++--- kernel/sched.c | 9 ++++----- 8 files changed, 29 insertions(+), 10 deletions(-) (limited to 'kernel') diff --git a/arch/ia64/include/asm/cputime.h b/arch/ia64/include/asm/cputime.h index d20b998cb91d..7fa8a8594660 100644 --- a/arch/ia64/include/asm/cputime.h +++ b/arch/ia64/include/asm/cputime.h @@ -30,6 +30,7 @@ typedef u64 cputime_t; typedef u64 cputime64_t; #define cputime_zero ((cputime_t)0) +#define cputime_one_jiffy jiffies_to_cputime(1) #define cputime_max ((~((cputime_t)0) >> 1) - 1) #define cputime_add(__a, __b) ((__a) + (__b)) #define cputime_sub(__a, __b) ((__a) - (__b)) diff --git a/arch/powerpc/include/asm/cputime.h b/arch/powerpc/include/asm/cputime.h index f42e623030ee..fa19f3fe05ff 100644 --- a/arch/powerpc/include/asm/cputime.h +++ b/arch/powerpc/include/asm/cputime.h @@ -18,6 +18,9 @@ #ifndef CONFIG_VIRT_CPU_ACCOUNTING #include +#ifdef __KERNEL__ +static inline void setup_cputime_one_jiffy(void) { } +#endif #else #include @@ -48,6 +51,11 @@ typedef u64 cputime64_t; #ifdef __KERNEL__ +/* + * One jiffy in timebase units computed during initialization + */ +extern cputime_t cputime_one_jiffy; + /* * Convert cputime <-> jiffies */ @@ -89,6 +97,11 @@ static inline cputime_t jiffies_to_cputime(const unsigned long jif) return ct; } +static inline void setup_cputime_one_jiffy(void) +{ + cputime_one_jiffy = jiffies_to_cputime(1); +} + static inline cputime64_t jiffies64_to_cputime64(const u64 jif) { cputime_t ct; diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index eae4511ceeac..211d7b0cd370 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -193,6 +193,8 @@ EXPORT_SYMBOL(__cputime_clockt_factor); DEFINE_PER_CPU(unsigned long, cputime_last_delta); DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta); +cputime_t cputime_one_jiffy; + static void calc_cputime_factors(void) { struct div_result res; @@ -500,6 +502,7 @@ static int __init iSeries_tb_recal(void) tb_to_xs = divres.result_low; vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; vdso_data->tb_to_xs = tb_to_xs; + setup_cputime_one_jiffy(); } else { printk( "Titan recalibrate: FAILED (difference > 4 percent)\n" @@ -945,6 +948,7 @@ void __init time_init(void) tb_ticks_per_usec = ppc_tb_freq / 1000000; tb_to_us = mulhwu_scale_factor(ppc_tb_freq, 1000000); calc_cputime_factors(); + setup_cputime_one_jiffy(); /* * Calculate the length of each tick in ns. It will not be diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h index 7a3817a656df..24b1244aadb9 100644 --- a/arch/s390/include/asm/cputime.h +++ b/arch/s390/include/asm/cputime.h @@ -42,6 +42,7 @@ __div(unsigned long long n, unsigned int base) #endif /* __s390x__ */ #define cputime_zero (0ULL) +#define cputime_one_jiffy jiffies_to_cputime(1) #define cputime_max ((~0UL >> 1) - 1) #define cputime_add(__a, __b) ((__a) + (__b)) #define cputime_sub(__a, __b) ((__a) - (__b)) diff --git a/include/asm-generic/cputime.h b/include/asm-generic/cputime.h index 1c1fa422d18a..ca0f239f0e13 100644 --- a/include/asm-generic/cputime.h +++ b/include/asm-generic/cputime.h @@ -7,6 +7,7 @@ typedef unsigned long cputime_t; #define cputime_zero (0UL) +#define cputime_one_jiffy jiffies_to_cputime(1) #define cputime_max ((~0UL >> 1) - 1) #define cputime_add(__a, __b) ((__a) + (__b)) #define cputime_sub(__a, __b) ((__a) - (__b)) diff --git a/kernel/itimer.c b/kernel/itimer.c index 21adff7b2a17..8078a32d3b10 100644 --- a/kernel/itimer.c +++ b/kernel/itimer.c @@ -64,7 +64,7 @@ static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, if (cputime_le(cval, t)) /* about to fire */ - cval = jiffies_to_cputime(1); + cval = cputime_one_jiffy; else cval = cputime_sub(cval, t); } @@ -161,7 +161,7 @@ static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, if (!cputime_eq(cval, cputime_zero) || !cputime_eq(nval, cputime_zero)) { if (cputime_gt(nval, cputime_zero)) - nval = cputime_add(nval, jiffies_to_cputime(1)); + nval = cputime_add(nval, cputime_one_jiffy); set_process_cpu_timer(tsk, clock_id, &nval, &cval); } it->expires = nval; diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index 69c92374355f..18bdde6f676f 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -1086,7 +1086,7 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, it->error += it->incr_error; if (it->error >= onecputick) { it->expires = cputime_sub(it->expires, - jiffies_to_cputime(1)); + cputime_one_jiffy); it->error -= onecputick; } } else @@ -1461,7 +1461,7 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, if (!cputime_eq(*oldval, cputime_zero)) { if (cputime_le(*oldval, now.cpu)) { /* Just about to fire. */ - *oldval = jiffies_to_cputime(1); + *oldval = cputime_one_jiffy; } else { *oldval = cputime_sub(*oldval, now.cpu); } @@ -1712,7 +1712,7 @@ static __init int init_posix_cpu_timers(void) register_posix_clock(CLOCK_PROCESS_CPUTIME_ID, &process); register_posix_clock(CLOCK_THREAD_CPUTIME_ID, &thread); - cputime_to_timespec(jiffies_to_cputime(1), &ts); + cputime_to_timespec(cputime_one_jiffy, &ts); onecputick = ts.tv_nsec; WARN_ON(ts.tv_sec != 0); diff --git a/kernel/sched.c b/kernel/sched.c index 1b59e265273b..8f977d5cc515 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -5031,17 +5031,16 @@ void account_idle_time(cputime_t cputime) */ void account_process_tick(struct task_struct *p, int user_tick) { - cputime_t one_jiffy = jiffies_to_cputime(1); - cputime_t one_jiffy_scaled = cputime_to_scaled(one_jiffy); + cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); struct rq *rq = this_rq(); if (user_tick) - account_user_time(p, one_jiffy, one_jiffy_scaled); + account_user_time(p, cputime_one_jiffy, one_jiffy_scaled); else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET)) - account_system_time(p, HARDIRQ_OFFSET, one_jiffy, + account_system_time(p, HARDIRQ_OFFSET, cputime_one_jiffy, one_jiffy_scaled); else - account_idle_time(one_jiffy); + account_idle_time(cputime_one_jiffy); } /* -- cgit v1.2.3 From 97fd9ed48ce2b807edc363bef3e817aeeb5cd5e6 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Tue, 21 Jul 2009 20:25:05 +0200 Subject: timers: Cache __next_timer_interrupt result Each time a cpu goes to sleep on a NOHZ=y system the timer wheel is searched for the next timer interrupt. It can take quite a few cycles to find the next pending timer. This patch adds a field to tvec_base that caches the result of __next_timer_interrupt. The hit ratio is around 80% on my thinkpad under normal use, on a server I've seen hit ratios from 5% to 95% dependent on the workload. -v2: jiffies wrap fixes Signed-off-by: Martin Schwidefsky Acked-by: Thomas Gleixner Cc: john stultz Cc: Venki Pallipadi LKML-Reference: <20090721202505.7d56a079@skybase> Signed-off-by: Ingo Molnar --- kernel/timer.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/timer.c b/kernel/timer.c index 0b36b9e5cc8b..5c1e49ec2f1b 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -72,6 +72,7 @@ struct tvec_base { spinlock_t lock; struct timer_list *running_timer; unsigned long timer_jiffies; + unsigned long next_timer; struct tvec_root tv1; struct tvec tv2; struct tvec tv3; @@ -622,6 +623,9 @@ __mod_timer(struct timer_list *timer, unsigned long expires, if (timer_pending(timer)) { detach_timer(timer, 0); + if (timer->expires == base->next_timer && + !tbase_get_deferrable(timer->base)) + base->next_timer = base->timer_jiffies; ret = 1; } else { if (pending_only) @@ -663,6 +667,9 @@ __mod_timer(struct timer_list *timer, unsigned long expires, } timer->expires = expires; + if (time_before(timer->expires, base->next_timer) && + !tbase_get_deferrable(timer->base)) + base->next_timer = timer->expires; internal_add_timer(base, timer); out_unlock: @@ -781,6 +788,9 @@ void add_timer_on(struct timer_list *timer, int cpu) spin_lock_irqsave(&base->lock, flags); timer_set_base(timer, base); debug_timer_activate(timer); + if (time_before(timer->expires, base->next_timer) && + !tbase_get_deferrable(timer->base)) + base->next_timer = timer->expires; internal_add_timer(base, timer); /* * Check whether the other CPU is idle and needs to be @@ -817,6 +827,9 @@ int del_timer(struct timer_list *timer) base = lock_timer_base(timer, &flags); if (timer_pending(timer)) { detach_timer(timer, 1); + if (timer->expires == base->next_timer && + !tbase_get_deferrable(timer->base)) + base->next_timer = base->timer_jiffies; ret = 1; } spin_unlock_irqrestore(&base->lock, flags); @@ -850,6 +863,9 @@ int try_to_del_timer_sync(struct timer_list *timer) ret = 0; if (timer_pending(timer)) { detach_timer(timer, 1); + if (timer->expires == base->next_timer && + !tbase_get_deferrable(timer->base)) + base->next_timer = base->timer_jiffies; ret = 1; } out: @@ -1134,7 +1150,9 @@ unsigned long get_next_timer_interrupt(unsigned long now) unsigned long expires; spin_lock(&base->lock); - expires = __next_timer_interrupt(base); + if (time_before_eq(base->next_timer, base->timer_jiffies)) + base->next_timer = __next_timer_interrupt(base); + expires = base->next_timer; spin_unlock(&base->lock); if (time_before_eq(expires, now)) @@ -1523,6 +1541,7 @@ static int __cpuinit init_timers_cpu(int cpu) INIT_LIST_HEAD(base->tv1.vec + j); base->timer_jiffies = jiffies; + base->next_timer = base->timer_jiffies; return 0; } @@ -1535,6 +1554,9 @@ static void migrate_timer_list(struct tvec_base *new_base, struct list_head *hea timer = list_first_entry(head, struct timer_list, entry); detach_timer(timer, 0); timer_set_base(timer, new_base); + if (time_before(timer->expires, new_base->next_timer) && + !tbase_get_deferrable(timer->base)) + new_base->next_timer = timer->expires; internal_add_timer(new_base, timer); } } -- cgit v1.2.3 From 31089c13bcb18d2cd2a3ddfbe3a28666346f237e Mon Sep 17 00:00:00 2001 From: John Stultz Date: Fri, 14 Aug 2009 15:47:18 +0200 Subject: timekeeping: Introduce timekeeping_leap_insert Move the adjustment of xtime, wall_to_monotonic and the update of the vsyscall variables to the timekeeping code. Signed-off-by: John Stultz Signed-off-by: Martin Schwidefsky LKML-Reference: <20090814134807.609730216@de.ibm.com> Signed-off-by: Thomas Gleixner --- include/linux/time.h | 1 + kernel/time/ntp.c | 7 ++----- kernel/time/timekeeping.c | 7 +++++++ 3 files changed, 10 insertions(+), 5 deletions(-) (limited to 'kernel') diff --git a/include/linux/time.h b/include/linux/time.h index ea16c1a01d51..e7c844558884 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -147,6 +147,7 @@ extern struct timespec timespec_trunc(struct timespec t, unsigned gran); extern int timekeeping_valid_for_hres(void); extern void update_wall_time(void); extern void update_xtime_cache(u64 nsec); +extern void timekeeping_leap_insert(int leapsecond); struct tms; extern void do_sys_times(struct tms *); diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 7fc64375ff43..4800f933910e 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -194,8 +194,7 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) case TIME_OK: break; case TIME_INS: - xtime.tv_sec--; - wall_to_monotonic.tv_sec++; + timekeeping_leap_insert(-1); time_state = TIME_OOP; printk(KERN_NOTICE "Clock: inserting leap second 23:59:60 UTC\n"); @@ -203,9 +202,8 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) res = HRTIMER_RESTART; break; case TIME_DEL: - xtime.tv_sec++; + timekeeping_leap_insert(1); time_tai--; - wall_to_monotonic.tv_sec--; time_state = TIME_WAIT; printk(KERN_NOTICE "Clock: deleting leap second 23:59:59 UTC\n"); @@ -219,7 +217,6 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) time_state = TIME_OK; break; } - update_vsyscall(&xtime, clock); write_sequnlock(&xtime_lock); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 02c0b2c9c674..b8b70fb545fc 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -58,6 +58,13 @@ void update_xtime_cache(u64 nsec) struct clocksource *clock; +/* must hold xtime_lock */ +void timekeeping_leap_insert(int leapsecond) +{ + xtime.tv_sec += leapsecond; + wall_to_monotonic.tv_sec -= leapsecond; + update_vsyscall(&xtime, clock); +} #ifdef CONFIG_GENERIC_TIME /** -- cgit v1.2.3 From a0f7d48bfb95a4c5172a2756dbc4b82afc8e9ae4 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:19 +0200 Subject: timekeeping: Remove clocksource inline functions The three inline functions clocksource_read, clocksource_enable and clocksource_disable are simple wrappers of an indirect call plus the copy from and to the mult_orig value. The functions are exclusively used by the timekeeping code which has intimate knowledge of the clocksource anyway. Therefore remove the inline functions. No functional change. Signed-off-by: Martin Schwidefsky Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134807.903108946@de.ibm.com> Signed-off-by: Thomas Gleixner --- include/linux/clocksource.h | 58 --------------------------------------------- kernel/time/timekeeping.c | 41 ++++++++++++++++++++++---------- 2 files changed, 28 insertions(+), 71 deletions(-) (limited to 'kernel') diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 1219be4fb42e..a1ef46f61c81 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -267,64 +267,6 @@ static inline u32 clocksource_hz2mult(u32 hz, u32 shift_constant) return (u32)tmp; } -/** - * clocksource_read: - Access the clocksource's current cycle value - * @cs: pointer to clocksource being read - * - * Uses the clocksource to return the current cycle_t value - */ -static inline cycle_t clocksource_read(struct clocksource *cs) -{ - return cs->read(cs); -} - -/** - * clocksource_enable: - enable clocksource - * @cs: pointer to clocksource - * - * Enables the specified clocksource. The clocksource callback - * function should start up the hardware and setup mult and field - * members of struct clocksource to reflect hardware capabilities. - */ -static inline int clocksource_enable(struct clocksource *cs) -{ - int ret = 0; - - if (cs->enable) - ret = cs->enable(cs); - - /* - * The frequency may have changed while the clocksource - * was disabled. If so the code in ->enable() must update - * the mult value to reflect the new frequency. Make sure - * mult_orig follows this change. - */ - cs->mult_orig = cs->mult; - - return ret; -} - -/** - * clocksource_disable: - disable clocksource - * @cs: pointer to clocksource - * - * Disables the specified clocksource. The clocksource callback - * function should power down the now unused hardware block to - * save power. - */ -static inline void clocksource_disable(struct clocksource *cs) -{ - /* - * Save mult_orig in mult so clocksource_enable() can - * restore the value regardless if ->enable() updates - * the value of mult or not. - */ - cs->mult = cs->mult_orig; - - if (cs->disable) - cs->disable(cs); -} - /** * cyc2ns - converts clocksource cycles to nanoseconds * @cs: Pointer to clocksource diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index b8b70fb545fc..016a2591d719 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -79,7 +79,7 @@ static void clocksource_forward_now(void) cycle_t cycle_now, cycle_delta; s64 nsec; - cycle_now = clocksource_read(clock); + cycle_now = clock->read(clock); cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; clock->cycle_last = cycle_now; @@ -114,7 +114,7 @@ void getnstimeofday(struct timespec *ts) *ts = xtime; /* read clocksource: */ - cycle_now = clocksource_read(clock); + cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; @@ -146,7 +146,7 @@ ktime_t ktime_get(void) nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec; /* read clocksource: */ - cycle_now = clocksource_read(clock); + cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; @@ -186,7 +186,7 @@ void ktime_get_ts(struct timespec *ts) tomono = wall_to_monotonic; /* read clocksource: */ - cycle_now = clocksource_read(clock); + cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; @@ -274,16 +274,29 @@ static void change_clocksource(void) clocksource_forward_now(); - if (clocksource_enable(new)) + if (new->enable && !new->enable(new)) return; + /* + * The frequency may have changed while the clocksource + * was disabled. If so the code in ->enable() must update + * the mult value to reflect the new frequency. Make sure + * mult_orig follows this change. + */ + new->mult_orig = new->mult; new->raw_time = clock->raw_time; old = clock; clock = new; - clocksource_disable(old); + /* + * Save mult_orig in mult so that the value can be restored + * regardless if ->enable() updates the value of mult or not. + */ + old->mult = old->mult_orig; + if (old->disable) + old->disable(old); clock->cycle_last = 0; - clock->cycle_last = clocksource_read(clock); + clock->cycle_last = clock->read(clock); clock->error = 0; clock->xtime_nsec = 0; clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH); @@ -373,7 +386,7 @@ void getrawmonotonic(struct timespec *ts) seq = read_seqbegin(&xtime_lock); /* read clocksource: */ - cycle_now = clocksource_read(clock); + cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; @@ -435,9 +448,12 @@ void __init timekeeping_init(void) ntp_init(); clock = clocksource_get_next(); - clocksource_enable(clock); + if (clock->enable) + clock->enable(clock); + /* set mult_orig on enable */ + clock->mult_orig = clock->mult; clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH); - clock->cycle_last = clocksource_read(clock); + clock->cycle_last = clock->read(clock); xtime.tv_sec = sec; xtime.tv_nsec = 0; @@ -477,8 +493,7 @@ static int timekeeping_resume(struct sys_device *dev) } update_xtime_cache(0); /* re-base the last cycle value */ - clock->cycle_last = 0; - clock->cycle_last = clocksource_read(clock); + clock->cycle_last = clock->read(clock); clock->error = 0; timekeeping_suspended = 0; write_sequnlock_irqrestore(&xtime_lock, flags); @@ -630,7 +645,7 @@ void update_wall_time(void) return; #ifdef CONFIG_GENERIC_TIME - offset = (clocksource_read(clock) - clock->cycle_last) & clock->mask; + offset = (clock->read(clock) - clock->cycle_last) & clock->mask; #else offset = clock->cycle_interval; #endif -- cgit v1.2.3 From 1be396794897f80bfc8774719ba60309a9e3d374 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:20 +0200 Subject: timekeeping: Move reset of cycle_last for tsc clocksource to tsc change_clocksource resets the cycle_last value to zero then sets it to a value read from the clocksource. The reset to zero is required only for the TSC clocksource to make the read_tsc function work after a resume. The reason is that the TSC read function uses cycle_last to detect backwards going TSCs. In the resume case cycle_last contains the TSC value from the last update before the suspend. On resume the TSC starts counting from 0 again and would trip over the cycle_last comparison. This is subtle and surprising. Move the reset to a resume function in the tsc code. Signed-off-by: Martin Schwidefsky Acked-by: Thomas Gleixner Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134808.142191175@de.ibm.com> Signed-off-by: Thomas Gleixner --- arch/x86/kernel/tsc.c | 6 ++++++ kernel/time/timekeeping.c | 1 - 2 files changed, 6 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 71f4368b357e..968425422c46 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -744,10 +744,16 @@ static cycle_t __vsyscall_fn vread_tsc(void) } #endif +static void resume_tsc(void) +{ + clocksource_tsc.cycle_last = 0; +} + static struct clocksource clocksource_tsc = { .name = "tsc", .rating = 300, .read = read_tsc, + .resume = resume_tsc, .mask = CLOCKSOURCE_MASK(64), .shift = 22, .flags = CLOCK_SOURCE_IS_CONTINUOUS | diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 016a2591d719..b5673016089f 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -295,7 +295,6 @@ static void change_clocksource(void) if (old->disable) old->disable(old); - clock->cycle_last = 0; clock->cycle_last = clock->read(clock); clock->error = 0; clock->xtime_nsec = 0; -- cgit v1.2.3 From f1b82746c1e93daf24e1ab9bfbd39bcdb2e7018b Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:21 +0200 Subject: clocksource: Cleanup clocksource selection If a non high-resolution clocksource is first set as override clock and then registered it becomes active even if the system is in one-shot mode. Move the override check from sysfs_override_clocksource to the clocksource selection. That fixes the bug and simplifies the code. The check in clocksource_register for double registration of the same clocksource is removed without replacement. To find the initial clocksource a new weak function in jiffies.c is defined that returns the jiffies clocksource. The architecture code can then override the weak function with a more suitable clocksource, e.g. the TOD clock on s390. [ tglx: Folded in a fix from John Stultz ] Signed-off-by: Martin Schwidefsky Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134808.388024160@de.ibm.com> Signed-off-by: Thomas Gleixner --- arch/s390/kernel/time.c | 4 ++ include/linux/clocksource.h | 2 + kernel/time/clocksource.c | 134 +++++++++++++++++--------------------------- kernel/time/jiffies.c | 6 +- kernel/time/timekeeping.c | 4 +- 5 files changed, 64 insertions(+), 86 deletions(-) (limited to 'kernel') diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index d4c8e9c47c81..afefe514df0f 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -205,6 +205,10 @@ static struct clocksource clocksource_tod = { .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; +struct clocksource * __init clocksource_default_clock(void) +{ + return &clocksource_tod; +} void update_vsyscall(struct timespec *wall_time, struct clocksource *clock) { diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index a1ef46f61c81..f263b3abf46e 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -322,6 +323,7 @@ extern void clocksource_touch_watchdog(void); extern struct clocksource* clocksource_get_next(void); extern void clocksource_change_rating(struct clocksource *cs, int rating); extern void clocksource_resume(void); +extern struct clocksource * __init __weak clocksource_default_clock(void); #ifdef CONFIG_GENERIC_TIME_VSYSCALL extern void update_vsyscall(struct timespec *ts, struct clocksource *c); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 7466cb811251..e91662e87cde 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -21,7 +21,6 @@ * * TODO WishList: * o Allow clocksource drivers to be unregistered - * o get rid of clocksource_jiffies extern */ #include @@ -107,12 +106,9 @@ u64 timecounter_cyc2time(struct timecounter *tc, } EXPORT_SYMBOL(timecounter_cyc2time); -/* XXX - Would like a better way for initializing curr_clocksource */ -extern struct clocksource clocksource_jiffies; - /*[Clocksource internal variables]--------- * curr_clocksource: - * currently selected clocksource. Initialized to clocksource_jiffies. + * currently selected clocksource. * next_clocksource: * pending next selected clocksource. * clocksource_list: @@ -123,9 +119,8 @@ extern struct clocksource clocksource_jiffies; * override_name: * Name of the user-specified clocksource. */ -static struct clocksource *curr_clocksource = &clocksource_jiffies; +static struct clocksource *curr_clocksource; static struct clocksource *next_clocksource; -static struct clocksource *clocksource_override; static LIST_HEAD(clocksource_list); static DEFINE_SPINLOCK(clocksource_lock); static char override_name[32]; @@ -320,6 +315,7 @@ void clocksource_touch_watchdog(void) clocksource_resume_watchdog(); } +#ifdef CONFIG_GENERIC_TIME /** * clocksource_get_next - Returns the selected clocksource * @@ -339,56 +335,65 @@ struct clocksource *clocksource_get_next(void) } /** - * select_clocksource - Selects the best registered clocksource. + * clocksource_select - Select the best clocksource available * * Private function. Must hold clocksource_lock when called. * * Select the clocksource with the best rating, or the clocksource, * which is selected by userspace override. */ -static struct clocksource *select_clocksource(void) +static void clocksource_select(void) { - struct clocksource *next; + struct clocksource *best, *cs; if (list_empty(&clocksource_list)) - return NULL; + return; + /* First clocksource on the list has the best rating. */ + best = list_first_entry(&clocksource_list, struct clocksource, list); + /* Check for the override clocksource. */ + list_for_each_entry(cs, &clocksource_list, list) { + if (strcmp(cs->name, override_name) != 0) + continue; + /* + * Check to make sure we don't switch to a non-highres + * capable clocksource if the tick code is in oneshot + * mode (highres or nohz) + */ + if (!(cs->flags & CLOCK_SOURCE_VALID_FOR_HRES) && + tick_oneshot_mode_active()) { + /* Override clocksource cannot be used. */ + printk(KERN_WARNING "Override clocksource %s is not " + "HRT compatible. Cannot switch while in " + "HRT/NOHZ mode\n", cs->name); + override_name[0] = 0; + } else + /* Override clocksource can be used. */ + best = cs; + break; + } + if (curr_clocksource != best) + next_clocksource = best; +} - if (clocksource_override) - next = clocksource_override; - else - next = list_entry(clocksource_list.next, struct clocksource, - list); +#else /* CONFIG_GENERIC_TIME */ - if (next == curr_clocksource) - return NULL; +static void clocksource_select(void) { } - return next; -} +#endif /* * Enqueue the clocksource sorted by rating */ -static int clocksource_enqueue(struct clocksource *c) +static void clocksource_enqueue(struct clocksource *cs) { - struct list_head *tmp, *entry = &clocksource_list; - - list_for_each(tmp, &clocksource_list) { - struct clocksource *cs; + struct list_head *entry = &clocksource_list; + struct clocksource *tmp; - cs = list_entry(tmp, struct clocksource, list); - if (cs == c) - return -EBUSY; + list_for_each_entry(tmp, &clocksource_list, list) /* Keep track of the place, where to insert */ - if (cs->rating >= c->rating) - entry = tmp; - } - list_add(&c->list, entry); - - if (strlen(c->name) == strlen(override_name) && - !strcmp(c->name, override_name)) - clocksource_override = c; - - return 0; + if (tmp->rating >= cs->rating) + entry = &tmp->list; + list_add(&cs->list, entry); } /** @@ -397,19 +402,16 @@ static int clocksource_enqueue(struct clocksource *c) * * Returns -EBUSY if registration fails, zero otherwise. */ -int clocksource_register(struct clocksource *c) +int clocksource_register(struct clocksource *cs) { unsigned long flags; - int ret; spin_lock_irqsave(&clocksource_lock, flags); - ret = clocksource_enqueue(c); - if (!ret) - next_clocksource = select_clocksource(); + clocksource_enqueue(cs); + clocksource_select(); spin_unlock_irqrestore(&clocksource_lock, flags); - if (!ret) - clocksource_check_watchdog(c); - return ret; + clocksource_check_watchdog(cs); + return 0; } EXPORT_SYMBOL(clocksource_register); @@ -425,7 +427,7 @@ void clocksource_change_rating(struct clocksource *cs, int rating) list_del(&cs->list); cs->rating = rating; clocksource_enqueue(cs); - next_clocksource = select_clocksource(); + clocksource_select(); spin_unlock_irqrestore(&clocksource_lock, flags); } @@ -438,9 +440,7 @@ void clocksource_unregister(struct clocksource *cs) spin_lock_irqsave(&clocksource_lock, flags); list_del(&cs->list); - if (clocksource_override == cs) - clocksource_override = NULL; - next_clocksource = select_clocksource(); + clocksource_select(); spin_unlock_irqrestore(&clocksource_lock, flags); } @@ -478,9 +478,7 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, struct sysdev_attribute *attr, const char *buf, size_t count) { - struct clocksource *ovr = NULL; size_t ret = count; - int len; /* strings from sysfs write are not 0 terminated! */ if (count >= sizeof(override_name)) @@ -495,37 +493,7 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, if (count > 0) memcpy(override_name, buf, count); override_name[count] = 0; - - len = strlen(override_name); - if (len) { - struct clocksource *cs; - - ovr = clocksource_override; - /* try to select it: */ - list_for_each_entry(cs, &clocksource_list, list) { - if (strlen(cs->name) == len && - !strcmp(cs->name, override_name)) - ovr = cs; - } - } - - /* - * Check to make sure we don't switch to a non-highres capable - * clocksource if the tick code is in oneshot mode (highres or nohz) - */ - if (tick_oneshot_mode_active() && ovr && - !(ovr->flags & CLOCK_SOURCE_VALID_FOR_HRES)) { - printk(KERN_WARNING "%s clocksource is not HRT compatible. " - "Cannot switch while in HRT/NOHZ mode\n", ovr->name); - ovr = NULL; - override_name[0] = 0; - } - - /* Reselect, when the override name has changed */ - if (ovr != clocksource_override) { - clocksource_override = ovr; - next_clocksource = select_clocksource(); - } + clocksource_select(); spin_unlock_irq(&clocksource_lock); diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c index c3f6c30816e3..5404a8456909 100644 --- a/kernel/time/jiffies.c +++ b/kernel/time/jiffies.c @@ -61,7 +61,6 @@ struct clocksource clocksource_jiffies = { .read = jiffies_read, .mask = 0xffffffff, /*32bits*/ .mult = NSEC_PER_JIFFY << JIFFIES_SHIFT, /* details above */ - .mult_orig = NSEC_PER_JIFFY << JIFFIES_SHIFT, .shift = JIFFIES_SHIFT, }; @@ -71,3 +70,8 @@ static int __init init_jiffies_clocksource(void) } core_initcall(init_jiffies_clocksource); + +struct clocksource * __init __weak clocksource_default_clock(void) +{ + return &clocksource_jiffies; +} diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index b5673016089f..325a9b63265a 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -269,7 +269,7 @@ static void change_clocksource(void) new = clocksource_get_next(); - if (clock == new) + if (!new || clock == new) return; clocksource_forward_now(); @@ -446,7 +446,7 @@ void __init timekeeping_init(void) ntp_init(); - clock = clocksource_get_next(); + clock = clocksource_default_clock(); if (clock->enable) clock->enable(clock); /* set mult_orig on enable */ -- cgit v1.2.3 From 8cf4e750f8459d51c2e8a035a201da4bf7aa996a Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:22 +0200 Subject: clocksource: Delay clocksource watchdog highres enablement The clocksource watchdog marks a clock as highres capable before it checked the deviation from the watchdog clocksource even for a single time. Make sure that the deviation is at least checked once before doing the switch to highres mode. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134808.627795883@de.ibm.com> Signed-off-by: Thomas Gleixner --- kernel/time/clocksource.c | 47 ++++++++++++++++++++++------------------------- 1 file changed, 22 insertions(+), 25 deletions(-) (limited to 'kernel') diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index e91662e87cde..76256c5aecb8 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -153,11 +153,8 @@ static unsigned long watchdog_resumed; #define WATCHDOG_INTERVAL (HZ >> 1) #define WATCHDOG_THRESHOLD (NSEC_PER_SEC >> 4) -static void clocksource_ratewd(struct clocksource *cs, int64_t delta) +static void clocksource_unstable(struct clocksource *cs, int64_t delta) { - if (delta > -WATCHDOG_THRESHOLD && delta < WATCHDOG_THRESHOLD) - return; - printk(KERN_WARNING "Clocksource %s unstable (delta = %Ld ns)\n", cs->name, delta); cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG); @@ -183,31 +180,31 @@ static void clocksource_watchdog(unsigned long data) list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list) { csnow = cs->read(cs); - if (unlikely(resumed)) { + /* Clocksource initialized ? */ + if (!(cs->flags & CLOCK_SOURCE_WATCHDOG)) { + cs->flags |= CLOCK_SOURCE_WATCHDOG; cs->wd_last = csnow; continue; } - /* Initialized ? */ - if (!(cs->flags & CLOCK_SOURCE_WATCHDOG)) { - if ((cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) && - (watchdog->flags & CLOCK_SOURCE_IS_CONTINUOUS)) { - cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES; - /* - * We just marked the clocksource as - * highres-capable, notify the rest of the - * system as well so that we transition - * into high-res mode: - */ - tick_clock_notify(); - } - cs->flags |= CLOCK_SOURCE_WATCHDOG; - cs->wd_last = csnow; - } else { - cs_nsec = cyc2ns(cs, (csnow - cs->wd_last) & cs->mask); - cs->wd_last = csnow; - /* Check the delta. Might remove from the list ! */ - clocksource_ratewd(cs, cs_nsec - wd_nsec); + /* Check the deviation from the watchdog clocksource. */ + cs_nsec = cyc2ns(cs, (csnow - cs->wd_last) & cs->mask); + cs->wd_last = csnow; + if (abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD) { + clocksource_unstable(cs, cs_nsec - wd_nsec); + continue; + } + + if (!(cs->flags & CLOCK_SOURCE_VALID_FOR_HRES) && + (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) && + (watchdog->flags & CLOCK_SOURCE_IS_CONTINUOUS)) { + cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES; + /* + * We just marked the clocksource as highres-capable, + * notify the rest of the system as well so that we + * transition into high-res mode: + */ + tick_clock_notify(); } } -- cgit v1.2.3 From 0f8e8ef7c204988246da5a42d576b7fa5277a8e4 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:23 +0200 Subject: clocksource: Simplify clocksource watchdog resume logic To resume the clocksource watchdog just remove the CLOCK_SOURCE_WATCHDOG bit from the watched clocksource. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134808.880925790@de.ibm.com> Signed-off-by: Thomas Gleixner --- kernel/time/clocksource.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) (limited to 'kernel') diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 76256c5aecb8..89a7b91bfbdd 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -145,7 +145,6 @@ static struct clocksource *watchdog; static struct timer_list watchdog_timer; static DEFINE_SPINLOCK(watchdog_lock); static cycle_t watchdog_last; -static unsigned long watchdog_resumed; /* * Interval: 0.5sec Threshold: 0.0625s @@ -167,12 +166,9 @@ static void clocksource_watchdog(unsigned long data) struct clocksource *cs, *tmp; cycle_t csnow, wdnow; int64_t wd_nsec, cs_nsec; - int resumed; spin_lock(&watchdog_lock); - resumed = test_and_clear_bit(0, &watchdog_resumed); - wdnow = watchdog->read(watchdog); wd_nsec = cyc2ns(watchdog, (wdnow - watchdog_last) & watchdog->mask); watchdog_last = wdnow; @@ -223,14 +219,26 @@ static void clocksource_watchdog(unsigned long data) } spin_unlock(&watchdog_lock); } + +static inline void clocksource_reset_watchdog(void) +{ + struct clocksource *cs; + + list_for_each_entry(cs, &watchdog_list, wd_list) + cs->flags &= ~CLOCK_SOURCE_WATCHDOG; +} + static void clocksource_resume_watchdog(void) { - set_bit(0, &watchdog_resumed); + unsigned long flags; + + spin_lock_irqsave(&watchdog_lock, flags); + clocksource_reset_watchdog(); + spin_unlock_irqrestore(&watchdog_lock, flags); } static void clocksource_check_watchdog(struct clocksource *cs) { - struct clocksource *cse; unsigned long flags; spin_lock_irqsave(&watchdog_lock, flags); @@ -256,8 +264,7 @@ static void clocksource_check_watchdog(struct clocksource *cs) watchdog_timer.function = clocksource_watchdog; /* Reset watchdog cycles */ - list_for_each_entry(cse, &watchdog_list, wd_list) - cse->flags &= ~CLOCK_SOURCE_WATCHDOG; + clocksource_reset_watchdog(); /* Start if list is not empty */ if (!list_empty(&watchdog_list)) { watchdog_last = watchdog->read(watchdog); -- cgit v1.2.3 From fb63a0ebe615fba9de8c75ea44ded999d1e24c65 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:24 +0200 Subject: clocksource: Refactor clocksource watchdog Refactor clocksource watchdog code to make it more readable. Add clocksource_dequeue_watchdog to remove a clocksource from the watchdog list when it is unregistered. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134809.110881699@de.ibm.com> Signed-off-by: Thomas Gleixner --- kernel/time/clocksource.c | 97 +++++++++++++++++++++++++++++++++-------------- 1 file changed, 69 insertions(+), 28 deletions(-) (limited to 'kernel') diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 89a7b91bfbdd..56aaa749645d 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -145,6 +145,7 @@ static struct clocksource *watchdog; static struct timer_list watchdog_timer; static DEFINE_SPINLOCK(watchdog_lock); static cycle_t watchdog_last; +static int watchdog_running; /* * Interval: 0.5sec Threshold: 0.0625s @@ -168,6 +169,8 @@ static void clocksource_watchdog(unsigned long data) int64_t wd_nsec, cs_nsec; spin_lock(&watchdog_lock); + if (!watchdog_running) + goto out; wdnow = watchdog->read(watchdog); wd_nsec = cyc2ns(watchdog, (wdnow - watchdog_last) & watchdog->mask); @@ -217,9 +220,30 @@ static void clocksource_watchdog(unsigned long data) watchdog_timer.expires += WATCHDOG_INTERVAL; add_timer_on(&watchdog_timer, next_cpu); } +out: spin_unlock(&watchdog_lock); } +static inline void clocksource_start_watchdog(void) +{ + if (watchdog_running || !watchdog || list_empty(&watchdog_list)) + return; + init_timer(&watchdog_timer); + watchdog_timer.function = clocksource_watchdog; + watchdog_last = watchdog->read(watchdog); + watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL; + add_timer_on(&watchdog_timer, cpumask_first(cpu_online_mask)); + watchdog_running = 1; +} + +static inline void clocksource_stop_watchdog(void) +{ + if (!watchdog_running || (watchdog && !list_empty(&watchdog_list))) + return; + del_timer(&watchdog_timer); + watchdog_running = 0; +} + static inline void clocksource_reset_watchdog(void) { struct clocksource *cs; @@ -237,55 +261,70 @@ static void clocksource_resume_watchdog(void) spin_unlock_irqrestore(&watchdog_lock, flags); } -static void clocksource_check_watchdog(struct clocksource *cs) +static void clocksource_enqueue_watchdog(struct clocksource *cs) { unsigned long flags; spin_lock_irqsave(&watchdog_lock, flags); if (cs->flags & CLOCK_SOURCE_MUST_VERIFY) { - int started = !list_empty(&watchdog_list); - + /* cs is a clocksource to be watched. */ list_add(&cs->wd_list, &watchdog_list); - if (!started && watchdog) { - watchdog_last = watchdog->read(watchdog); - watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL; - add_timer_on(&watchdog_timer, - cpumask_first(cpu_online_mask)); - } + cs->flags &= ~CLOCK_SOURCE_WATCHDOG; } else { + /* cs is a watchdog. */ if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES; - + /* Pick the best watchdog. */ if (!watchdog || cs->rating > watchdog->rating) { - if (watchdog) - del_timer(&watchdog_timer); watchdog = cs; - init_timer(&watchdog_timer); - watchdog_timer.function = clocksource_watchdog; - /* Reset watchdog cycles */ clocksource_reset_watchdog(); - /* Start if list is not empty */ - if (!list_empty(&watchdog_list)) { - watchdog_last = watchdog->read(watchdog); - watchdog_timer.expires = - jiffies + WATCHDOG_INTERVAL; - add_timer_on(&watchdog_timer, - cpumask_first(cpu_online_mask)); - } } } + /* Check if the watchdog timer needs to be started. */ + clocksource_start_watchdog(); spin_unlock_irqrestore(&watchdog_lock, flags); } -#else -static void clocksource_check_watchdog(struct clocksource *cs) + +static void clocksource_dequeue_watchdog(struct clocksource *cs) +{ + struct clocksource *tmp; + unsigned long flags; + + spin_lock_irqsave(&watchdog_lock, flags); + if (cs->flags & CLOCK_SOURCE_MUST_VERIFY) { + /* cs is a watched clocksource. */ + list_del_init(&cs->wd_list); + } else if (cs == watchdog) { + /* Reset watchdog cycles */ + clocksource_reset_watchdog(); + /* Current watchdog is removed. Find an alternative. */ + watchdog = NULL; + list_for_each_entry(tmp, &clocksource_list, list) { + if (tmp == cs || tmp->flags & CLOCK_SOURCE_MUST_VERIFY) + continue; + if (!watchdog || tmp->rating > watchdog->rating) + watchdog = tmp; + } + } + cs->flags &= ~CLOCK_SOURCE_WATCHDOG; + /* Check if the watchdog timer needs to be stopped. */ + clocksource_stop_watchdog(); + spin_unlock_irqrestore(&watchdog_lock, flags); +} + +#else /* CONFIG_CLOCKSOURCE_WATCHDOG */ + +static void clocksource_enqueue_watchdog(struct clocksource *cs) { if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES; } +static inline void clocksource_dequeue_watchdog(struct clocksource *cs) { } static inline void clocksource_resume_watchdog(void) { } -#endif + +#endif /* CONFIG_CLOCKSOURCE_WATCHDOG */ /** * clocksource_resume - resume the clocksource(s) @@ -414,14 +453,13 @@ int clocksource_register(struct clocksource *cs) clocksource_enqueue(cs); clocksource_select(); spin_unlock_irqrestore(&clocksource_lock, flags); - clocksource_check_watchdog(cs); + clocksource_enqueue_watchdog(cs); return 0; } EXPORT_SYMBOL(clocksource_register); /** * clocksource_change_rating - Change the rating of a registered clocksource - * */ void clocksource_change_rating(struct clocksource *cs, int rating) { @@ -434,6 +472,7 @@ void clocksource_change_rating(struct clocksource *cs, int rating) clocksource_select(); spin_unlock_irqrestore(&clocksource_lock, flags); } +EXPORT_SYMBOL(clocksource_change_rating); /** * clocksource_unregister - remove a registered clocksource @@ -442,11 +481,13 @@ void clocksource_unregister(struct clocksource *cs) { unsigned long flags; + clocksource_dequeue_watchdog(cs); spin_lock_irqsave(&clocksource_lock, flags); list_del(&cs->list); clocksource_select(); spin_unlock_irqrestore(&clocksource_lock, flags); } +EXPORT_SYMBOL(clocksource_unregister); #ifdef CONFIG_SYSFS /** -- cgit v1.2.3 From c55c87c892c1875deace0c8fc28787335277fdf2 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:25 +0200 Subject: clocksource: Move watchdog downgrade to a work queue thread Move the downgrade of an unstable clocksource from the timer interrupt context into the process context of a work queue thread. This is needed to be able to do the clocksource switch with stop_machine. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134809.354926067@de.ibm.com> Signed-off-by: Thomas Gleixner --- include/linux/clocksource.h | 1 + kernel/time/clocksource.c | 56 +++++++++++++++++++++++++++++++-------------- 2 files changed, 40 insertions(+), 17 deletions(-) (limited to 'kernel') diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index f263b3abf46e..19ad43af62d0 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -213,6 +213,7 @@ extern struct clocksource *clock; /* current clocksource */ #define CLOCK_SOURCE_WATCHDOG 0x10 #define CLOCK_SOURCE_VALID_FOR_HRES 0x20 +#define CLOCK_SOURCE_UNSTABLE 0x40 /* simplify initialization of mask field */ #define CLOCKSOURCE_MASK(bits) (cycle_t)((bits) < 64 ? ((1ULL<<(bits))-1) : -1) diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 56aaa749645d..f1508019bfb4 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -143,10 +143,13 @@ fs_initcall(clocksource_done_booting); static LIST_HEAD(watchdog_list); static struct clocksource *watchdog; static struct timer_list watchdog_timer; +static struct work_struct watchdog_work; static DEFINE_SPINLOCK(watchdog_lock); static cycle_t watchdog_last; static int watchdog_running; +static void clocksource_watchdog_work(struct work_struct *work); + /* * Interval: 0.5sec Threshold: 0.0625s */ @@ -158,15 +161,16 @@ static void clocksource_unstable(struct clocksource *cs, int64_t delta) printk(KERN_WARNING "Clocksource %s unstable (delta = %Ld ns)\n", cs->name, delta); cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG); - clocksource_change_rating(cs, 0); - list_del(&cs->wd_list); + cs->flags |= CLOCK_SOURCE_UNSTABLE; + schedule_work(&watchdog_work); } static void clocksource_watchdog(unsigned long data) { - struct clocksource *cs, *tmp; + struct clocksource *cs; cycle_t csnow, wdnow; int64_t wd_nsec, cs_nsec; + int next_cpu; spin_lock(&watchdog_lock); if (!watchdog_running) @@ -176,7 +180,12 @@ static void clocksource_watchdog(unsigned long data) wd_nsec = cyc2ns(watchdog, (wdnow - watchdog_last) & watchdog->mask); watchdog_last = wdnow; - list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list) { + list_for_each_entry(cs, &watchdog_list, wd_list) { + + /* Clocksource already marked unstable? */ + if (cs->flags & CLOCK_SOURCE_UNSTABLE) + continue; + csnow = cs->read(cs); /* Clocksource initialized ? */ @@ -207,19 +216,15 @@ static void clocksource_watchdog(unsigned long data) } } - if (!list_empty(&watchdog_list)) { - /* - * Cycle through CPUs to check if the CPUs stay - * synchronized to each other. - */ - int next_cpu = cpumask_next(raw_smp_processor_id(), - cpu_online_mask); - - if (next_cpu >= nr_cpu_ids) - next_cpu = cpumask_first(cpu_online_mask); - watchdog_timer.expires += WATCHDOG_INTERVAL; - add_timer_on(&watchdog_timer, next_cpu); - } + /* + * Cycle through CPUs to check if the CPUs stay synchronized + * to each other. + */ + next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask); + if (next_cpu >= nr_cpu_ids) + next_cpu = cpumask_first(cpu_online_mask); + watchdog_timer.expires += WATCHDOG_INTERVAL; + add_timer_on(&watchdog_timer, next_cpu); out: spin_unlock(&watchdog_lock); } @@ -228,6 +233,7 @@ static inline void clocksource_start_watchdog(void) { if (watchdog_running || !watchdog || list_empty(&watchdog_list)) return; + INIT_WORK(&watchdog_work, clocksource_watchdog_work); init_timer(&watchdog_timer); watchdog_timer.function = clocksource_watchdog; watchdog_last = watchdog->read(watchdog); @@ -313,6 +319,22 @@ static void clocksource_dequeue_watchdog(struct clocksource *cs) spin_unlock_irqrestore(&watchdog_lock, flags); } +static void clocksource_watchdog_work(struct work_struct *work) +{ + struct clocksource *cs, *tmp; + unsigned long flags; + + spin_lock_irqsave(&watchdog_lock, flags); + list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list) + if (cs->flags & CLOCK_SOURCE_UNSTABLE) { + list_del_init(&cs->wd_list); + clocksource_change_rating(cs, 0); + } + /* Check if the watchdog timer needs to be stopped. */ + clocksource_stop_watchdog(); + spin_unlock(&watchdog_lock); +} + #else /* CONFIG_CLOCKSOURCE_WATCHDOG */ static void clocksource_enqueue_watchdog(struct clocksource *cs) -- cgit v1.2.3 From 155ec60226ae0ae2aadaa57c951a58a359331030 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:26 +0200 Subject: timekeeping: Introduce struct timekeeper Add struct timekeeper to keep the internal values timekeeping.c needs in regard to the currently selected clock source. This moves the timekeeping intervals, xtime_nsec and the ntp error value from struct clocksource to struct timekeeper. The raw_time is removed from the clocksource as well. It gets treated like xtime as a global variable. Eventually xtime raw_time should be moved to struct timekeeper. [ tglx: minor cleanup ] Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134809.613209842@de.ibm.com> Signed-off-by: Thomas Gleixner --- arch/s390/kernel/time.c | 1 - include/linux/clocksource.h | 54 +--------- kernel/time/clocksource.c | 6 +- kernel/time/timekeeping.c | 235 +++++++++++++++++++++++++++++--------------- 4 files changed, 164 insertions(+), 132 deletions(-) (limited to 'kernel') diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index afefe514df0f..e76c2e7a8b9a 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -280,7 +280,6 @@ void __init time_init(void) now = get_clock(); tod_to_timeval(now - TOD_UNIX_EPOCH, &xtime); clocksource_tod.cycle_last = now; - clocksource_tod.raw_time = xtime; tod_to_timeval(sched_clock_base_cc - TOD_UNIX_EPOCH, &ts); set_normalized_timespec(&wall_to_monotonic, -ts.tv_sec, -ts.tv_nsec); write_sequnlock_irqrestore(&xtime_lock, flags); diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 19ad43af62d0..e12e3095e2fb 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -155,8 +155,6 @@ extern u64 timecounter_cyc2time(struct timecounter *tc, * @flags: flags describing special properties * @vread: vsyscall based read * @resume: resume function for the clocksource, if necessary - * @cycle_interval: Used internally by timekeeping core, please ignore. - * @xtime_interval: Used internally by timekeeping core, please ignore. */ struct clocksource { /* @@ -182,19 +180,12 @@ struct clocksource { #define CLKSRC_FSYS_MMIO_SET(mmio, addr) do { } while (0) #endif - /* timekeeping specific data, ignore */ - cycle_t cycle_interval; - u64 xtime_interval; - u32 raw_interval; /* * Second part is written at each timer interrupt * Keep it in a different cache line to dirty no * more than one cache line. */ cycle_t cycle_last ____cacheline_aligned_in_smp; - u64 xtime_nsec; - s64 error; - struct timespec raw_time; #ifdef CONFIG_CLOCKSOURCE_WATCHDOG /* Watchdog related data, used by the framework */ @@ -203,8 +194,6 @@ struct clocksource { #endif }; -extern struct clocksource *clock; /* current clocksource */ - /* * Clock source flags bits:: */ @@ -270,50 +259,15 @@ static inline u32 clocksource_hz2mult(u32 hz, u32 shift_constant) } /** - * cyc2ns - converts clocksource cycles to nanoseconds - * @cs: Pointer to clocksource - * @cycles: Cycles + * clocksource_cyc2ns - converts clocksource cycles to nanoseconds * - * Uses the clocksource and ntp ajdustment to convert cycle_ts to nanoseconds. + * Converts cycles to nanoseconds, using the given mult and shift. * * XXX - This could use some mult_lxl_ll() asm optimization */ -static inline s64 cyc2ns(struct clocksource *cs, cycle_t cycles) +static inline s64 clocksource_cyc2ns(cycle_t cycles, u32 mult, u32 shift) { - u64 ret = (u64)cycles; - ret = (ret * cs->mult) >> cs->shift; - return ret; -} - -/** - * clocksource_calculate_interval - Calculates a clocksource interval struct - * - * @c: Pointer to clocksource. - * @length_nsec: Desired interval length in nanoseconds. - * - * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment - * pair and interval request. - * - * Unless you're the timekeeping code, you should not be using this! - */ -static inline void clocksource_calculate_interval(struct clocksource *c, - unsigned long length_nsec) -{ - u64 tmp; - - /* Do the ns -> cycle conversion first, using original mult */ - tmp = length_nsec; - tmp <<= c->shift; - tmp += c->mult_orig/2; - do_div(tmp, c->mult_orig); - - c->cycle_interval = (cycle_t)tmp; - if (c->cycle_interval == 0) - c->cycle_interval = 1; - - /* Go back from cycles -> shifted ns, this time use ntp adjused mult */ - c->xtime_interval = (u64)c->cycle_interval * c->mult; - c->raw_interval = ((u64)c->cycle_interval * c->mult_orig) >> c->shift; + return ((u64) cycles * mult) >> shift; } diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index f1508019bfb4..f18c9a6bdcf4 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -177,7 +177,8 @@ static void clocksource_watchdog(unsigned long data) goto out; wdnow = watchdog->read(watchdog); - wd_nsec = cyc2ns(watchdog, (wdnow - watchdog_last) & watchdog->mask); + wd_nsec = clocksource_cyc2ns((wdnow - watchdog_last) & watchdog->mask, + watchdog->mult, watchdog->shift); watchdog_last = wdnow; list_for_each_entry(cs, &watchdog_list, wd_list) { @@ -196,7 +197,8 @@ static void clocksource_watchdog(unsigned long data) } /* Check the deviation from the watchdog clocksource. */ - cs_nsec = cyc2ns(cs, (csnow - cs->wd_last) & cs->mask); + cs_nsec = clocksource_cyc2ns((csnow - cs->wd_last) & + cs->mask, cs->mult, cs->shift); cs->wd_last = csnow; if (abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD) { clocksource_unstable(cs, cs_nsec - wd_nsec); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 325a9b63265a..7af45cbf6b13 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -19,6 +19,65 @@ #include #include +/* Structure holding internal timekeeping values. */ +struct timekeeper { + /* Current clocksource used for timekeeping. */ + struct clocksource *clock; + + /* Number of clock cycles in one NTP interval. */ + cycle_t cycle_interval; + /* Number of clock shifted nano seconds in one NTP interval. */ + u64 xtime_interval; + /* Raw nano seconds accumulated per NTP interval. */ + u32 raw_interval; + + /* Clock shifted nano seconds remainder not stored in xtime.tv_nsec. */ + u64 xtime_nsec; + /* Difference between accumulated time and NTP time in ntp + * shifted nano seconds. */ + s64 ntp_error; +}; + +struct timekeeper timekeeper; + +/** + * timekeeper_setup_internals - Set up internals to use clocksource clock. + * + * @clock: Pointer to clocksource. + * + * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment + * pair and interval request. + * + * Unless you're the timekeeping code, you should not be using this! + */ +static void timekeeper_setup_internals(struct clocksource *clock) +{ + cycle_t interval; + u64 tmp; + + timekeeper.clock = clock; + clock->cycle_last = clock->read(clock); + + /* Do the ns -> cycle conversion first, using original mult */ + tmp = NTP_INTERVAL_LENGTH; + tmp <<= clock->shift; + tmp += clock->mult_orig/2; + do_div(tmp, clock->mult_orig); + if (tmp == 0) + tmp = 1; + + interval = (cycle_t) tmp; + timekeeper.cycle_interval = interval; + + /* Go back from cycles -> shifted ns */ + timekeeper.xtime_interval = (u64) interval * clock->mult; + timekeeper.raw_interval = + ((u64) interval * clock->mult_orig) >> clock->shift; + + timekeeper.xtime_nsec = 0; + + timekeeper.ntp_error = 0; +} /* * This read-write spinlock protects us from races in SMP while @@ -46,6 +105,11 @@ struct timespec xtime __attribute__ ((aligned (16))); struct timespec wall_to_monotonic __attribute__ ((aligned (16))); static unsigned long total_sleep_time; /* seconds */ +/* + * The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. + */ +struct timespec raw_time; + /* flag for if timekeeping is suspended */ int __read_mostly timekeeping_suspended; @@ -56,42 +120,42 @@ void update_xtime_cache(u64 nsec) timespec_add_ns(&xtime_cache, nsec); } -struct clocksource *clock; - /* must hold xtime_lock */ void timekeeping_leap_insert(int leapsecond) { xtime.tv_sec += leapsecond; wall_to_monotonic.tv_sec -= leapsecond; - update_vsyscall(&xtime, clock); + update_vsyscall(&xtime, timekeeper.clock); } #ifdef CONFIG_GENERIC_TIME /** - * clocksource_forward_now - update clock to the current time + * timekeeping_forward_now - update clock to the current time * * Forward the current clock to update its state since the last call to * update_wall_time(). This is useful before significant clock changes, * as it avoids having to deal with this time offset explicitly. */ -static void clocksource_forward_now(void) +static void timekeeping_forward_now(void) { cycle_t cycle_now, cycle_delta; + struct clocksource *clock; s64 nsec; + clock = timekeeper.clock; cycle_now = clock->read(clock); cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; clock->cycle_last = cycle_now; - nsec = cyc2ns(clock, cycle_delta); + nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); /* If arch requires, add in gettimeoffset() */ nsec += arch_gettimeoffset(); timespec_add_ns(&xtime, nsec); - nsec = ((s64)cycle_delta * clock->mult_orig) >> clock->shift; - clock->raw_time.tv_nsec += nsec; + nsec = clocksource_cyc2ns(cycle_delta, clock->mult_orig, clock->shift); + timespec_add_ns(&raw_time, nsec); } /** @@ -103,6 +167,7 @@ static void clocksource_forward_now(void) void getnstimeofday(struct timespec *ts) { cycle_t cycle_now, cycle_delta; + struct clocksource *clock; unsigned long seq; s64 nsecs; @@ -114,13 +179,15 @@ void getnstimeofday(struct timespec *ts) *ts = xtime; /* read clocksource: */ + clock = timekeeper.clock; cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; /* convert to nanoseconds: */ - nsecs = cyc2ns(clock, cycle_delta); + nsecs = clocksource_cyc2ns(cycle_delta, clock->mult, + clock->shift); /* If arch requires, add in gettimeoffset() */ nsecs += arch_gettimeoffset(); @@ -135,6 +202,7 @@ EXPORT_SYMBOL(getnstimeofday); ktime_t ktime_get(void) { cycle_t cycle_now, cycle_delta; + struct clocksource *clock; unsigned int seq; s64 secs, nsecs; @@ -146,13 +214,15 @@ ktime_t ktime_get(void) nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec; /* read clocksource: */ + clock = timekeeper.clock; cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; /* convert to nanoseconds: */ - nsecs += cyc2ns(clock, cycle_delta); + nsecs += clocksource_cyc2ns(cycle_delta, clock->mult, + clock->shift); } while (read_seqretry(&xtime_lock, seq)); /* @@ -174,6 +244,7 @@ EXPORT_SYMBOL_GPL(ktime_get); void ktime_get_ts(struct timespec *ts) { cycle_t cycle_now, cycle_delta; + struct clocksource *clock; struct timespec tomono; unsigned int seq; s64 nsecs; @@ -186,13 +257,15 @@ void ktime_get_ts(struct timespec *ts) tomono = wall_to_monotonic; /* read clocksource: */ + clock = timekeeper.clock; cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; /* convert to nanoseconds: */ - nsecs = cyc2ns(clock, cycle_delta); + nsecs = clocksource_cyc2ns(cycle_delta, clock->mult, + clock->shift); } while (read_seqretry(&xtime_lock, seq)); @@ -233,7 +306,7 @@ int do_settimeofday(struct timespec *tv) write_seqlock_irqsave(&xtime_lock, flags); - clocksource_forward_now(); + timekeeping_forward_now(); ts_delta.tv_sec = tv->tv_sec - xtime.tv_sec; ts_delta.tv_nsec = tv->tv_nsec - xtime.tv_nsec; @@ -243,10 +316,10 @@ int do_settimeofday(struct timespec *tv) update_xtime_cache(0); - clock->error = 0; + timekeeper.ntp_error = 0; ntp_clear(); - update_vsyscall(&xtime, clock); + update_vsyscall(&xtime, timekeeper.clock); write_sequnlock_irqrestore(&xtime_lock, flags); @@ -269,10 +342,10 @@ static void change_clocksource(void) new = clocksource_get_next(); - if (!new || clock == new) + if (!new || timekeeper.clock == new) return; - clocksource_forward_now(); + timekeeping_forward_now(); if (new->enable && !new->enable(new)) return; @@ -284,9 +357,9 @@ static void change_clocksource(void) */ new->mult_orig = new->mult; - new->raw_time = clock->raw_time; - old = clock; - clock = new; + old = timekeeper.clock; + timekeeper_setup_internals(new); + /* * Save mult_orig in mult so that the value can be restored * regardless if ->enable() updates the value of mult or not. @@ -295,22 +368,10 @@ static void change_clocksource(void) if (old->disable) old->disable(old); - clock->cycle_last = clock->read(clock); - clock->error = 0; - clock->xtime_nsec = 0; - clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH); - tick_clock_notify(); - - /* - * We're holding xtime lock and waking up klogd would deadlock - * us on enqueue. So no printing! - printk(KERN_INFO "Time: %s clocksource has been installed.\n", - clock->name); - */ } #else /* GENERIC_TIME */ -static inline void clocksource_forward_now(void) { } +static inline void timekeeping_forward_now(void) { } static inline void change_clocksource(void) { } /** @@ -380,20 +441,23 @@ void getrawmonotonic(struct timespec *ts) unsigned long seq; s64 nsecs; cycle_t cycle_now, cycle_delta; + struct clocksource *clock; do { seq = read_seqbegin(&xtime_lock); /* read clocksource: */ + clock = timekeeper.clock; cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; /* convert to nanoseconds: */ - nsecs = ((s64)cycle_delta * clock->mult_orig) >> clock->shift; + nsecs = clocksource_cyc2ns(cycle_delta, clock->mult_orig, + clock->shift); - *ts = clock->raw_time; + *ts = raw_time; } while (read_seqretry(&xtime_lock, seq)); @@ -413,7 +477,7 @@ int timekeeping_valid_for_hres(void) do { seq = read_seqbegin(&xtime_lock); - ret = clock->flags & CLOCK_SOURCE_VALID_FOR_HRES; + ret = timekeeper.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES; } while (read_seqretry(&xtime_lock, seq)); @@ -439,6 +503,7 @@ unsigned long __attribute__((weak)) read_persistent_clock(void) */ void __init timekeeping_init(void) { + struct clocksource *clock; unsigned long flags; unsigned long sec = read_persistent_clock(); @@ -451,11 +516,13 @@ void __init timekeeping_init(void) clock->enable(clock); /* set mult_orig on enable */ clock->mult_orig = clock->mult; - clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH); - clock->cycle_last = clock->read(clock); + + timekeeper_setup_internals(clock); xtime.tv_sec = sec; xtime.tv_nsec = 0; + raw_time.tv_sec = 0; + raw_time.tv_nsec = 0; set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec); update_xtime_cache(0); @@ -492,8 +559,8 @@ static int timekeeping_resume(struct sys_device *dev) } update_xtime_cache(0); /* re-base the last cycle value */ - clock->cycle_last = clock->read(clock); - clock->error = 0; + timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock); + timekeeper.ntp_error = 0; timekeeping_suspended = 0; write_sequnlock_irqrestore(&xtime_lock, flags); @@ -514,7 +581,7 @@ static int timekeeping_suspend(struct sys_device *dev, pm_message_t state) timekeeping_suspend_time = read_persistent_clock(); write_seqlock_irqsave(&xtime_lock, flags); - clocksource_forward_now(); + timekeeping_forward_now(); timekeeping_suspended = 1; write_sequnlock_irqrestore(&xtime_lock, flags); @@ -549,7 +616,7 @@ device_initcall(timekeeping_init_device); * If the error is already larger, we look ahead even further * to compensate for late or lost adjustments. */ -static __always_inline int clocksource_bigadjust(s64 error, s64 *interval, +static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval, s64 *offset) { s64 tick_error, i; @@ -565,7 +632,7 @@ static __always_inline int clocksource_bigadjust(s64 error, s64 *interval, * here. This is tuned so that an error of about 1 msec is adjusted * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks). */ - error2 = clock->error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ); + error2 = timekeeper.ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ); error2 = abs(error2); for (look_ahead = 0; error2 > 0; look_ahead++) error2 >>= 2; @@ -574,8 +641,9 @@ static __always_inline int clocksource_bigadjust(s64 error, s64 *interval, * Now calculate the error in (1 << look_ahead) ticks, but first * remove the single look ahead already included in the error. */ - tick_error = tick_length >> (NTP_SCALE_SHIFT - clock->shift + 1); - tick_error -= clock->xtime_interval >> 1; + tick_error = tick_length >> + (NTP_SCALE_SHIFT - timekeeper.clock->shift + 1); + tick_error -= timekeeper.xtime_interval >> 1; error = ((error - tick_error) >> look_ahead) + tick_error; /* Finally calculate the adjustment shift value. */ @@ -600,18 +668,19 @@ static __always_inline int clocksource_bigadjust(s64 error, s64 *interval, * this is optimized for the most common adjustments of -1,0,1, * for other values we can do a bit more work. */ -static void clocksource_adjust(s64 offset) +static void timekeeping_adjust(s64 offset) { - s64 error, interval = clock->cycle_interval; + s64 error, interval = timekeeper.cycle_interval; int adj; - error = clock->error >> (NTP_SCALE_SHIFT - clock->shift - 1); + error = timekeeper.ntp_error >> + (NTP_SCALE_SHIFT - timekeeper.clock->shift - 1); if (error > interval) { error >>= 2; if (likely(error <= interval)) adj = 1; else - adj = clocksource_bigadjust(error, &interval, &offset); + adj = timekeeping_bigadjust(error, &interval, &offset); } else if (error < -interval) { error >>= 2; if (likely(error >= -interval)) { @@ -619,15 +688,15 @@ static void clocksource_adjust(s64 offset) interval = -interval; offset = -offset; } else - adj = clocksource_bigadjust(error, &interval, &offset); + adj = timekeeping_bigadjust(error, &interval, &offset); } else return; - clock->mult += adj; - clock->xtime_interval += interval; - clock->xtime_nsec -= offset; - clock->error -= (interval - offset) << - (NTP_SCALE_SHIFT - clock->shift); + timekeeper.clock->mult += adj; + timekeeper.xtime_interval += interval; + timekeeper.xtime_nsec -= offset; + timekeeper.ntp_error -= (interval - offset) << + (NTP_SCALE_SHIFT - timekeeper.clock->shift); } /** @@ -637,53 +706,59 @@ static void clocksource_adjust(s64 offset) */ void update_wall_time(void) { + struct clocksource *clock; cycle_t offset; + s64 nsecs; /* Make sure we're fully resumed: */ if (unlikely(timekeeping_suspended)) return; + clock = timekeeper.clock; #ifdef CONFIG_GENERIC_TIME offset = (clock->read(clock) - clock->cycle_last) & clock->mask; #else - offset = clock->cycle_interval; + offset = timekeeper.cycle_interval; #endif - clock->xtime_nsec = (s64)xtime.tv_nsec << clock->shift; + timekeeper.xtime_nsec = (s64)xtime.tv_nsec << clock->shift; /* normally this loop will run just once, however in the * case of lost or late ticks, it will accumulate correctly. */ - while (offset >= clock->cycle_interval) { + while (offset >= timekeeper.cycle_interval) { + u64 nsecps = (u64)NSEC_PER_SEC << clock->shift; + /* accumulate one interval */ - offset -= clock->cycle_interval; - clock->cycle_last += clock->cycle_interval; + offset -= timekeeper.cycle_interval; + clock->cycle_last += timekeeper.cycle_interval; - clock->xtime_nsec += clock->xtime_interval; - if (clock->xtime_nsec >= (u64)NSEC_PER_SEC << clock->shift) { - clock->xtime_nsec -= (u64)NSEC_PER_SEC << clock->shift; + timekeeper.xtime_nsec += timekeeper.xtime_interval; + if (timekeeper.xtime_nsec >= nsecps) { + timekeeper.xtime_nsec -= nsecps; xtime.tv_sec++; second_overflow(); } - clock->raw_time.tv_nsec += clock->raw_interval; - if (clock->raw_time.tv_nsec >= NSEC_PER_SEC) { - clock->raw_time.tv_nsec -= NSEC_PER_SEC; - clock->raw_time.tv_sec++; + raw_time.tv_nsec += timekeeper.raw_interval; + if (raw_time.tv_nsec >= NSEC_PER_SEC) { + raw_time.tv_nsec -= NSEC_PER_SEC; + raw_time.tv_sec++; } /* accumulate error between NTP and clock interval */ - clock->error += tick_length; - clock->error -= clock->xtime_interval << (NTP_SCALE_SHIFT - clock->shift); + timekeeper.ntp_error += tick_length; + timekeeper.ntp_error -= timekeeper.xtime_interval << + (NTP_SCALE_SHIFT - clock->shift); } /* correct the clock when NTP error is too big */ - clocksource_adjust(offset); + timekeeping_adjust(offset); /* * Since in the loop above, we accumulate any amount of time * in xtime_nsec over a second into xtime.tv_sec, its possible for * xtime_nsec to be fairly small after the loop. Further, if we're - * slightly speeding the clocksource up in clocksource_adjust(), + * slightly speeding the clocksource up in timekeeping_adjust(), * its possible the required corrective factor to xtime_nsec could * cause it to underflow. * @@ -695,24 +770,26 @@ void update_wall_time(void) * We'll correct this error next time through this function, when * xtime_nsec is not as small. */ - if (unlikely((s64)clock->xtime_nsec < 0)) { - s64 neg = -(s64)clock->xtime_nsec; - clock->xtime_nsec = 0; - clock->error += neg << (NTP_SCALE_SHIFT - clock->shift); + if (unlikely((s64)timekeeper.xtime_nsec < 0)) { + s64 neg = -(s64)timekeeper.xtime_nsec; + timekeeper.xtime_nsec = 0; + timekeeper.ntp_error += neg << (NTP_SCALE_SHIFT - clock->shift); } /* store full nanoseconds into xtime after rounding it up and * add the remainder to the error difference. */ - xtime.tv_nsec = ((s64)clock->xtime_nsec >> clock->shift) + 1; - clock->xtime_nsec -= (s64)xtime.tv_nsec << clock->shift; - clock->error += clock->xtime_nsec << (NTP_SCALE_SHIFT - clock->shift); + xtime.tv_nsec = ((s64)timekeeper.xtime_nsec >> clock->shift) + 1; + timekeeper.xtime_nsec -= (s64)xtime.tv_nsec << clock->shift; + timekeeper.ntp_error += timekeeper.xtime_nsec << + (NTP_SCALE_SHIFT - clock->shift); - update_xtime_cache(cyc2ns(clock, offset)); + nsecs = clocksource_cyc2ns(offset, clock->mult, clock->shift); + update_xtime_cache(nsecs); /* check to see if there is a new clocksource to use */ change_clocksource(); - update_vsyscall(&xtime, clock); + update_vsyscall(&xtime, timekeeper.clock); } /** -- cgit v1.2.3 From 23ce72117c714baab794e66c8daf343bf6a912bf Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:27 +0200 Subject: timekeeping: Add xtime_shift and ntp_error_shift to struct timekeeper The xtime_nsec value in the timekeeper structure is shifted by a few bits to improve precision. This happens to be the same value as the clock->shift. To improve readability add xtime_shift to the timekeeper and use it instead of the clock->shift. Likewise add ntp_error_shift and replace all (NTP_SCALE_SHIFT - clock->shift) expressions. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134809.871899606@de.ibm.com> Signed-off-by: Thomas Gleixner --- kernel/time/timekeeping.c | 33 +++++++++++++++++++-------------- 1 file changed, 19 insertions(+), 14 deletions(-) (limited to 'kernel') diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 7af45cbf6b13..dfdab1cefe1e 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -23,6 +23,8 @@ struct timekeeper { /* Current clocksource used for timekeeping. */ struct clocksource *clock; + /* The shift value of the current clocksource. */ + int shift; /* Number of clock cycles in one NTP interval. */ cycle_t cycle_interval; @@ -36,6 +38,9 @@ struct timekeeper { /* Difference between accumulated time and NTP time in ntp * shifted nano seconds. */ s64 ntp_error; + /* Shift conversion between clock shifted nano seconds and + * ntp shifted nano seconds. */ + int ntp_error_shift; }; struct timekeeper timekeeper; @@ -75,8 +80,10 @@ static void timekeeper_setup_internals(struct clocksource *clock) ((u64) interval * clock->mult_orig) >> clock->shift; timekeeper.xtime_nsec = 0; + timekeeper.shift = clock->shift; timekeeper.ntp_error = 0; + timekeeper.ntp_error_shift = NTP_SCALE_SHIFT - clock->shift; } /* @@ -641,8 +648,7 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval, * Now calculate the error in (1 << look_ahead) ticks, but first * remove the single look ahead already included in the error. */ - tick_error = tick_length >> - (NTP_SCALE_SHIFT - timekeeper.clock->shift + 1); + tick_error = tick_length >> (timekeeper.ntp_error_shift + 1); tick_error -= timekeeper.xtime_interval >> 1; error = ((error - tick_error) >> look_ahead) + tick_error; @@ -673,8 +679,7 @@ static void timekeeping_adjust(s64 offset) s64 error, interval = timekeeper.cycle_interval; int adj; - error = timekeeper.ntp_error >> - (NTP_SCALE_SHIFT - timekeeper.clock->shift - 1); + error = timekeeper.ntp_error >> (timekeeper.ntp_error_shift - 1); if (error > interval) { error >>= 2; if (likely(error <= interval)) @@ -696,7 +701,7 @@ static void timekeeping_adjust(s64 offset) timekeeper.xtime_interval += interval; timekeeper.xtime_nsec -= offset; timekeeper.ntp_error -= (interval - offset) << - (NTP_SCALE_SHIFT - timekeeper.clock->shift); + timekeeper.ntp_error_shift; } /** @@ -708,7 +713,7 @@ void update_wall_time(void) { struct clocksource *clock; cycle_t offset; - s64 nsecs; + u64 nsecs; /* Make sure we're fully resumed: */ if (unlikely(timekeeping_suspended)) @@ -720,13 +725,13 @@ void update_wall_time(void) #else offset = timekeeper.cycle_interval; #endif - timekeeper.xtime_nsec = (s64)xtime.tv_nsec << clock->shift; + timekeeper.xtime_nsec = (s64)xtime.tv_nsec << timekeeper.shift; /* normally this loop will run just once, however in the * case of lost or late ticks, it will accumulate correctly. */ while (offset >= timekeeper.cycle_interval) { - u64 nsecps = (u64)NSEC_PER_SEC << clock->shift; + u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift; /* accumulate one interval */ offset -= timekeeper.cycle_interval; @@ -748,7 +753,7 @@ void update_wall_time(void) /* accumulate error between NTP and clock interval */ timekeeper.ntp_error += tick_length; timekeeper.ntp_error -= timekeeper.xtime_interval << - (NTP_SCALE_SHIFT - clock->shift); + timekeeper.ntp_error_shift; } /* correct the clock when NTP error is too big */ @@ -773,16 +778,16 @@ void update_wall_time(void) if (unlikely((s64)timekeeper.xtime_nsec < 0)) { s64 neg = -(s64)timekeeper.xtime_nsec; timekeeper.xtime_nsec = 0; - timekeeper.ntp_error += neg << (NTP_SCALE_SHIFT - clock->shift); + timekeeper.ntp_error += neg << timekeeper.ntp_error_shift; } /* store full nanoseconds into xtime after rounding it up and * add the remainder to the error difference. */ - xtime.tv_nsec = ((s64)timekeeper.xtime_nsec >> clock->shift) + 1; - timekeeper.xtime_nsec -= (s64)xtime.tv_nsec << clock->shift; - timekeeper.ntp_error += timekeeper.xtime_nsec << - (NTP_SCALE_SHIFT - clock->shift); + xtime.tv_nsec = ((s64) timekeeper.xtime_nsec >> timekeeper.shift) + 1; + timekeeper.xtime_nsec -= (s64) xtime.tv_nsec << timekeeper.shift; + timekeeper.ntp_error += timekeeper.xtime_nsec << + timekeeper.ntp_error_shift; nsecs = clocksource_cyc2ns(offset, clock->mult, clock->shift); update_xtime_cache(nsecs); -- cgit v1.2.3 From 0a54419836254a27baecd9037103171bcbabaf67 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:28 +0200 Subject: timekeeping: Move NTP adjusted clock multiplier to struct timekeeper The clocksource structure has two multipliers, the unmodified multiplier clock->mult_orig and the NTP corrected multiplier clock->mult. The NTP multiplier is misplaced in the struct clocksource, this is private information of the timekeeping code. Add the mult field to the struct timekeeper to contain the NTP corrected value, keep the unmodifed multiplier in clock->mult and remove clock->mult_orig. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134810.149047645@de.ibm.com> Signed-off-by: Thomas Gleixner --- arch/arm/plat-omap/common.c | 7 ++---- include/linux/clocksource.h | 4 +--- kernel/time/timekeeping.c | 53 ++++++++++++++++++++------------------------- 3 files changed, 27 insertions(+), 37 deletions(-) (limited to 'kernel') diff --git a/arch/arm/plat-omap/common.c b/arch/arm/plat-omap/common.c index ebcf006406f9..95587b6c0259 100644 --- a/arch/arm/plat-omap/common.c +++ b/arch/arm/plat-omap/common.c @@ -253,11 +253,8 @@ static struct clocksource clocksource_32k = { */ unsigned long long sched_clock(void) { - unsigned long long ret; - - ret = (unsigned long long)clocksource_32k.read(&clocksource_32k); - ret = (ret * clocksource_32k.mult_orig) >> clocksource_32k.shift; - return ret; + return clocksource_cyc2ns(clocksource_32k.read(&clocksource_32k), + clocksource_32k.mult, clocksource_32k.shift); } static int __init omap_init_clocksource_32k(void) diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index e12e3095e2fb..e34015effeb6 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -149,8 +149,7 @@ extern u64 timecounter_cyc2time(struct timecounter *tc, * @disable: optional function to disable the clocksource * @mask: bitmask for two's complement * subtraction of non 64 bit counters - * @mult: cycle to nanosecond multiplier (adjusted by NTP) - * @mult_orig: cycle to nanosecond multiplier (unadjusted by NTP) + * @mult: cycle to nanosecond multiplier * @shift: cycle to nanosecond divisor (power of two) * @flags: flags describing special properties * @vread: vsyscall based read @@ -168,7 +167,6 @@ struct clocksource { void (*disable)(struct clocksource *cs); cycle_t mask; u32 mult; - u32 mult_orig; u32 shift; unsigned long flags; cycle_t (*vread)(void); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index dfdab1cefe1e..f4056f6c2632 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -41,6 +41,8 @@ struct timekeeper { /* Shift conversion between clock shifted nano seconds and * ntp shifted nano seconds. */ int ntp_error_shift; + /* NTP adjusted clock multiplier */ + u32 mult; }; struct timekeeper timekeeper; @@ -66,8 +68,8 @@ static void timekeeper_setup_internals(struct clocksource *clock) /* Do the ns -> cycle conversion first, using original mult */ tmp = NTP_INTERVAL_LENGTH; tmp <<= clock->shift; - tmp += clock->mult_orig/2; - do_div(tmp, clock->mult_orig); + tmp += clock->mult/2; + do_div(tmp, clock->mult); if (tmp == 0) tmp = 1; @@ -77,13 +79,20 @@ static void timekeeper_setup_internals(struct clocksource *clock) /* Go back from cycles -> shifted ns */ timekeeper.xtime_interval = (u64) interval * clock->mult; timekeeper.raw_interval = - ((u64) interval * clock->mult_orig) >> clock->shift; + ((u64) interval * clock->mult) >> clock->shift; timekeeper.xtime_nsec = 0; timekeeper.shift = clock->shift; timekeeper.ntp_error = 0; timekeeper.ntp_error_shift = NTP_SCALE_SHIFT - clock->shift; + + /* + * The timekeeper keeps its own mult values for the currently + * active clocksource. These value will be adjusted via NTP + * to counteract clock drifting. + */ + timekeeper.mult = clock->mult; } /* @@ -154,14 +163,15 @@ static void timekeeping_forward_now(void) cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; clock->cycle_last = cycle_now; - nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); + nsec = clocksource_cyc2ns(cycle_delta, timekeeper.mult, + timekeeper.shift); /* If arch requires, add in gettimeoffset() */ nsec += arch_gettimeoffset(); timespec_add_ns(&xtime, nsec); - nsec = clocksource_cyc2ns(cycle_delta, clock->mult_orig, clock->shift); + nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); timespec_add_ns(&raw_time, nsec); } @@ -193,8 +203,8 @@ void getnstimeofday(struct timespec *ts) cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; /* convert to nanoseconds: */ - nsecs = clocksource_cyc2ns(cycle_delta, clock->mult, - clock->shift); + nsecs = clocksource_cyc2ns(cycle_delta, timekeeper.mult, + timekeeper.shift); /* If arch requires, add in gettimeoffset() */ nsecs += arch_gettimeoffset(); @@ -228,8 +238,8 @@ ktime_t ktime_get(void) cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; /* convert to nanoseconds: */ - nsecs += clocksource_cyc2ns(cycle_delta, clock->mult, - clock->shift); + nsecs += clocksource_cyc2ns(cycle_delta, timekeeper.mult, + timekeeper.shift); } while (read_seqretry(&xtime_lock, seq)); /* @@ -271,8 +281,8 @@ void ktime_get_ts(struct timespec *ts) cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; /* convert to nanoseconds: */ - nsecs = clocksource_cyc2ns(cycle_delta, clock->mult, - clock->shift); + nsecs = clocksource_cyc2ns(cycle_delta, timekeeper.mult, + timekeeper.shift); } while (read_seqretry(&xtime_lock, seq)); @@ -356,22 +366,10 @@ static void change_clocksource(void) if (new->enable && !new->enable(new)) return; - /* - * The frequency may have changed while the clocksource - * was disabled. If so the code in ->enable() must update - * the mult value to reflect the new frequency. Make sure - * mult_orig follows this change. - */ - new->mult_orig = new->mult; old = timekeeper.clock; timekeeper_setup_internals(new); - /* - * Save mult_orig in mult so that the value can be restored - * regardless if ->enable() updates the value of mult or not. - */ - old->mult = old->mult_orig; if (old->disable) old->disable(old); @@ -461,7 +459,7 @@ void getrawmonotonic(struct timespec *ts) cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; /* convert to nanoseconds: */ - nsecs = clocksource_cyc2ns(cycle_delta, clock->mult_orig, + nsecs = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); *ts = raw_time; @@ -521,9 +519,6 @@ void __init timekeeping_init(void) clock = clocksource_default_clock(); if (clock->enable) clock->enable(clock); - /* set mult_orig on enable */ - clock->mult_orig = clock->mult; - timekeeper_setup_internals(clock); xtime.tv_sec = sec; @@ -697,7 +692,7 @@ static void timekeeping_adjust(s64 offset) } else return; - timekeeper.clock->mult += adj; + timekeeper.mult += adj; timekeeper.xtime_interval += interval; timekeeper.xtime_nsec -= offset; timekeeper.ntp_error -= (interval - offset) << @@ -789,7 +784,7 @@ void update_wall_time(void) timekeeper.ntp_error += timekeeper.xtime_nsec << timekeeper.ntp_error_shift; - nsecs = clocksource_cyc2ns(offset, clock->mult, clock->shift); + nsecs = clocksource_cyc2ns(offset, timekeeper.mult, timekeeper.shift); update_xtime_cache(nsecs); /* check to see if there is a new clocksource to use */ -- cgit v1.2.3 From 2ba2a3054fdffc8e6452f4ee120760322a6fbd43 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:29 +0200 Subject: timekeeping: Add timekeeper read_clock helper functions Add timekeeper_read_clock_ntp and timekeeper_read_clock_raw and use them for getnstimeofday, ktime_get, ktime_get_ts and getrawmonotonic. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134810.435105711@de.ibm.com> Signed-off-by: Thomas Gleixner --- kernel/time/timekeeping.c | 91 ++++++++++++++++++++--------------------------- 1 file changed, 38 insertions(+), 53 deletions(-) (limited to 'kernel') diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index f4056f6c2632..27ae01b596b7 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -95,6 +95,40 @@ static void timekeeper_setup_internals(struct clocksource *clock) timekeeper.mult = clock->mult; } +/* Timekeeper helper functions. */ +static inline s64 timekeeping_get_ns(void) +{ + cycle_t cycle_now, cycle_delta; + struct clocksource *clock; + + /* read clocksource: */ + clock = timekeeper.clock; + cycle_now = clock->read(clock); + + /* calculate the delta since the last update_wall_time: */ + cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; + + /* return delta convert to nanoseconds using ntp adjusted mult. */ + return clocksource_cyc2ns(cycle_delta, timekeeper.mult, + timekeeper.shift); +} + +static inline s64 timekeeping_get_ns_raw(void) +{ + cycle_t cycle_now, cycle_delta; + struct clocksource *clock; + + /* read clocksource: */ + clock = timekeeper.clock; + cycle_now = clock->read(clock); + + /* calculate the delta since the last update_wall_time: */ + cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; + + /* return delta convert to nanoseconds using ntp adjusted mult. */ + return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); +} + /* * This read-write spinlock protects us from races in SMP while * playing with xtime. @@ -183,8 +217,6 @@ static void timekeeping_forward_now(void) */ void getnstimeofday(struct timespec *ts) { - cycle_t cycle_now, cycle_delta; - struct clocksource *clock; unsigned long seq; s64 nsecs; @@ -194,17 +226,7 @@ void getnstimeofday(struct timespec *ts) seq = read_seqbegin(&xtime_lock); *ts = xtime; - - /* read clocksource: */ - clock = timekeeper.clock; - cycle_now = clock->read(clock); - - /* calculate the delta since the last update_wall_time: */ - cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; - - /* convert to nanoseconds: */ - nsecs = clocksource_cyc2ns(cycle_delta, timekeeper.mult, - timekeeper.shift); + nsecs = timekeeping_get_ns(); /* If arch requires, add in gettimeoffset() */ nsecs += arch_gettimeoffset(); @@ -218,8 +240,6 @@ EXPORT_SYMBOL(getnstimeofday); ktime_t ktime_get(void) { - cycle_t cycle_now, cycle_delta; - struct clocksource *clock; unsigned int seq; s64 secs, nsecs; @@ -229,17 +249,7 @@ ktime_t ktime_get(void) seq = read_seqbegin(&xtime_lock); secs = xtime.tv_sec + wall_to_monotonic.tv_sec; nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec; - - /* read clocksource: */ - clock = timekeeper.clock; - cycle_now = clock->read(clock); - - /* calculate the delta since the last update_wall_time: */ - cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; - - /* convert to nanoseconds: */ - nsecs += clocksource_cyc2ns(cycle_delta, timekeeper.mult, - timekeeper.shift); + nsecs += timekeeping_get_ns(); } while (read_seqretry(&xtime_lock, seq)); /* @@ -260,8 +270,6 @@ EXPORT_SYMBOL_GPL(ktime_get); */ void ktime_get_ts(struct timespec *ts) { - cycle_t cycle_now, cycle_delta; - struct clocksource *clock; struct timespec tomono; unsigned int seq; s64 nsecs; @@ -272,17 +280,7 @@ void ktime_get_ts(struct timespec *ts) seq = read_seqbegin(&xtime_lock); *ts = xtime; tomono = wall_to_monotonic; - - /* read clocksource: */ - clock = timekeeper.clock; - cycle_now = clock->read(clock); - - /* calculate the delta since the last update_wall_time: */ - cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; - - /* convert to nanoseconds: */ - nsecs = clocksource_cyc2ns(cycle_delta, timekeeper.mult, - timekeeper.shift); + nsecs = timekeeping_get_ns(); } while (read_seqretry(&xtime_lock, seq)); @@ -445,23 +443,10 @@ void getrawmonotonic(struct timespec *ts) { unsigned long seq; s64 nsecs; - cycle_t cycle_now, cycle_delta; - struct clocksource *clock; do { seq = read_seqbegin(&xtime_lock); - - /* read clocksource: */ - clock = timekeeper.clock; - cycle_now = clock->read(clock); - - /* calculate the delta since the last update_wall_time: */ - cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; - - /* convert to nanoseconds: */ - nsecs = clocksource_cyc2ns(cycle_delta, clock->mult, - clock->shift); - + nsecs = timekeeping_get_ns_raw(); *ts = raw_time; } while (read_seqretry(&xtime_lock, seq)); -- cgit v1.2.3 From 75c5158f70c065b9704b924503d96e8297838f79 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:30 +0200 Subject: timekeeping: Update clocksource with stop_machine update_wall_time calls change_clocksource HZ times per second to check if a new clock source is available. In close to 100% of all calls there is no new clock. Replace the tick based check by an update done with stop_machine. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134810.711836357@de.ibm.com> Signed-off-by: Thomas Gleixner --- include/linux/clocksource.h | 2 + kernel/time/clocksource.c | 112 +++++++++++++++++--------------------------- kernel/time/timekeeping.c | 41 ++++++++++------ 3 files changed, 72 insertions(+), 83 deletions(-) (limited to 'kernel') diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index e34015effeb6..9ea40ff26f0e 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -291,4 +291,6 @@ static inline void update_vsyscall_tz(void) } #endif +extern void timekeeping_notify(struct clocksource *clock); + #endif /* _LINUX_CLOCKSOURCE_H */ diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index f18c9a6bdcf4..a1657b5fdeb9 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -109,35 +109,17 @@ EXPORT_SYMBOL(timecounter_cyc2time); /*[Clocksource internal variables]--------- * curr_clocksource: * currently selected clocksource. - * next_clocksource: - * pending next selected clocksource. * clocksource_list: * linked list with the registered clocksources - * clocksource_lock: - * protects manipulations to curr_clocksource and next_clocksource - * and the clocksource_list + * clocksource_mutex: + * protects manipulations to curr_clocksource and the clocksource_list * override_name: * Name of the user-specified clocksource. */ static struct clocksource *curr_clocksource; -static struct clocksource *next_clocksource; static LIST_HEAD(clocksource_list); -static DEFINE_SPINLOCK(clocksource_lock); +static DEFINE_MUTEX(clocksource_mutex); static char override_name[32]; -static int finished_booting; - -/* clocksource_done_booting - Called near the end of core bootup - * - * Hack to avoid lots of clocksource churn at boot time. - * We use fs_initcall because we want this to start before - * device_initcall but after subsys_initcall. - */ -static int __init clocksource_done_booting(void) -{ - finished_booting = 1; - return 0; -} -fs_initcall(clocksource_done_booting); #ifdef CONFIG_CLOCKSOURCE_WATCHDOG static LIST_HEAD(watchdog_list); @@ -356,18 +338,16 @@ static inline void clocksource_resume_watchdog(void) { } void clocksource_resume(void) { struct clocksource *cs; - unsigned long flags; - spin_lock_irqsave(&clocksource_lock, flags); + mutex_lock(&clocksource_mutex); - list_for_each_entry(cs, &clocksource_list, list) { + list_for_each_entry(cs, &clocksource_list, list) if (cs->resume) cs->resume(); - } clocksource_resume_watchdog(); - spin_unlock_irqrestore(&clocksource_lock, flags); + mutex_unlock(&clocksource_mutex); } /** @@ -383,28 +363,13 @@ void clocksource_touch_watchdog(void) } #ifdef CONFIG_GENERIC_TIME -/** - * clocksource_get_next - Returns the selected clocksource - * - */ -struct clocksource *clocksource_get_next(void) -{ - unsigned long flags; - spin_lock_irqsave(&clocksource_lock, flags); - if (next_clocksource && finished_booting) { - curr_clocksource = next_clocksource; - next_clocksource = NULL; - } - spin_unlock_irqrestore(&clocksource_lock, flags); - - return curr_clocksource; -} +static int finished_booting; /** * clocksource_select - Select the best clocksource available * - * Private function. Must hold clocksource_lock when called. + * Private function. Must hold clocksource_mutex when called. * * Select the clocksource with the best rating, or the clocksource, * which is selected by userspace override. @@ -413,7 +378,7 @@ static void clocksource_select(void) { struct clocksource *best, *cs; - if (list_empty(&clocksource_list)) + if (!finished_booting || list_empty(&clocksource_list)) return; /* First clocksource on the list has the best rating. */ best = list_first_entry(&clocksource_list, struct clocksource, list); @@ -438,13 +403,31 @@ static void clocksource_select(void) best = cs; break; } - if (curr_clocksource != best) - next_clocksource = best; + if (curr_clocksource != best) { + printk(KERN_INFO "Switching to clocksource %s\n", best->name); + curr_clocksource = best; + timekeeping_notify(curr_clocksource); + } } +/* + * clocksource_done_booting - Called near the end of core bootup + * + * Hack to avoid lots of clocksource churn at boot time. + * We use fs_initcall because we want this to start before + * device_initcall but after subsys_initcall. + */ +static int __init clocksource_done_booting(void) +{ + finished_booting = 1; + clocksource_select(); + return 0; +} +fs_initcall(clocksource_done_booting); + #else /* CONFIG_GENERIC_TIME */ -static void clocksource_select(void) { } +static inline void clocksource_select(void) { } #endif @@ -471,13 +454,11 @@ static void clocksource_enqueue(struct clocksource *cs) */ int clocksource_register(struct clocksource *cs) { - unsigned long flags; - - spin_lock_irqsave(&clocksource_lock, flags); + mutex_lock(&clocksource_mutex); clocksource_enqueue(cs); clocksource_select(); - spin_unlock_irqrestore(&clocksource_lock, flags); clocksource_enqueue_watchdog(cs); + mutex_unlock(&clocksource_mutex); return 0; } EXPORT_SYMBOL(clocksource_register); @@ -487,14 +468,12 @@ EXPORT_SYMBOL(clocksource_register); */ void clocksource_change_rating(struct clocksource *cs, int rating) { - unsigned long flags; - - spin_lock_irqsave(&clocksource_lock, flags); + mutex_lock(&clocksource_mutex); list_del(&cs->list); cs->rating = rating; clocksource_enqueue(cs); clocksource_select(); - spin_unlock_irqrestore(&clocksource_lock, flags); + mutex_unlock(&clocksource_mutex); } EXPORT_SYMBOL(clocksource_change_rating); @@ -503,13 +482,11 @@ EXPORT_SYMBOL(clocksource_change_rating); */ void clocksource_unregister(struct clocksource *cs) { - unsigned long flags; - + mutex_lock(&clocksource_mutex); clocksource_dequeue_watchdog(cs); - spin_lock_irqsave(&clocksource_lock, flags); list_del(&cs->list); clocksource_select(); - spin_unlock_irqrestore(&clocksource_lock, flags); + mutex_unlock(&clocksource_mutex); } EXPORT_SYMBOL(clocksource_unregister); @@ -527,9 +504,9 @@ sysfs_show_current_clocksources(struct sys_device *dev, { ssize_t count = 0; - spin_lock_irq(&clocksource_lock); + mutex_lock(&clocksource_mutex); count = snprintf(buf, PAGE_SIZE, "%s\n", curr_clocksource->name); - spin_unlock_irq(&clocksource_lock); + mutex_unlock(&clocksource_mutex); return count; } @@ -557,14 +534,14 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, if (buf[count-1] == '\n') count--; - spin_lock_irq(&clocksource_lock); + mutex_lock(&clocksource_mutex); if (count > 0) memcpy(override_name, buf, count); override_name[count] = 0; clocksource_select(); - spin_unlock_irq(&clocksource_lock); + mutex_unlock(&clocksource_mutex); return ret; } @@ -584,7 +561,7 @@ sysfs_show_available_clocksources(struct sys_device *dev, struct clocksource *src; ssize_t count = 0; - spin_lock_irq(&clocksource_lock); + mutex_lock(&clocksource_mutex); list_for_each_entry(src, &clocksource_list, list) { /* * Don't show non-HRES clocksource if the tick code is @@ -596,7 +573,7 @@ sysfs_show_available_clocksources(struct sys_device *dev, max((ssize_t)PAGE_SIZE - count, (ssize_t)0), "%s ", src->name); } - spin_unlock_irq(&clocksource_lock); + mutex_unlock(&clocksource_mutex); count += snprintf(buf + count, max((ssize_t)PAGE_SIZE - count, (ssize_t)0), "\n"); @@ -651,11 +628,10 @@ device_initcall(init_clocksource_sysfs); */ static int __init boot_override_clocksource(char* str) { - unsigned long flags; - spin_lock_irqsave(&clocksource_lock, flags); + mutex_lock(&clocksource_mutex); if (str) strlcpy(override_name, str, sizeof(override_name)); - spin_unlock_irqrestore(&clocksource_lock, flags); + mutex_unlock(&clocksource_mutex); return 1; } diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 27ae01b596b7..41579e7fcf9d 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -18,6 +18,7 @@ #include #include #include +#include /* Structure holding internal timekeeping values. */ struct timekeeper { @@ -179,6 +180,7 @@ void timekeeping_leap_insert(int leapsecond) } #ifdef CONFIG_GENERIC_TIME + /** * timekeeping_forward_now - update clock to the current time * @@ -351,31 +353,40 @@ EXPORT_SYMBOL(do_settimeofday); * * Accumulates current time interval and initializes new clocksource */ -static void change_clocksource(void) +static int change_clocksource(void *data) { struct clocksource *new, *old; - new = clocksource_get_next(); - - if (!new || timekeeper.clock == new) - return; + new = (struct clocksource *) data; timekeeping_forward_now(); + if (!new->enable || new->enable(new) == 0) { + old = timekeeper.clock; + timekeeper_setup_internals(new); + if (old->disable) + old->disable(old); + } + return 0; +} - if (new->enable && !new->enable(new)) +/** + * timekeeping_notify - Install a new clock source + * @clock: pointer to the clock source + * + * This function is called from clocksource.c after a new, better clock + * source has been registered. The caller holds the clocksource_mutex. + */ +void timekeeping_notify(struct clocksource *clock) +{ + if (timekeeper.clock == clock) return; - - old = timekeeper.clock; - timekeeper_setup_internals(new); - - if (old->disable) - old->disable(old); - + stop_machine(change_clocksource, clock, NULL); tick_clock_notify(); } + #else /* GENERIC_TIME */ + static inline void timekeeping_forward_now(void) { } -static inline void change_clocksource(void) { } /** * ktime_get - get the monotonic time in ktime_t format @@ -416,6 +427,7 @@ void ktime_get_ts(struct timespec *ts) ts->tv_nsec + tomono.tv_nsec); } EXPORT_SYMBOL_GPL(ktime_get_ts); + #endif /* !GENERIC_TIME */ /** @@ -773,7 +785,6 @@ void update_wall_time(void) update_xtime_cache(nsecs); /* check to see if there is a new clocksource to use */ - change_clocksource(); update_vsyscall(&xtime, timekeeper.clock); } -- cgit v1.2.3 From d4f587c67fc39e0030ddd718675e252e208da4d7 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:31 +0200 Subject: timekeeping: Increase granularity of read_persistent_clock() The persistent clock of some architectures (e.g. s390) have a better granularity than seconds. To reduce the delta between the host clock and the guest clock in a virtualized system change the read_persistent_clock function to return a struct timespec. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134811.013873340@de.ibm.com> Signed-off-by: Thomas Gleixner --- arch/m68knommu/kernel/time.c | 5 ++-- arch/mips/dec/time.c | 5 ++-- arch/mips/lasat/ds1603.c | 5 ++-- arch/mips/lasat/sysctl.c | 8 ++++-- arch/mips/lemote/lm2e/setup.c | 5 ++-- arch/mips/mti-malta/malta-time.c | 5 ++-- arch/mips/pmc-sierra/yosemite/setup.c | 5 ++-- arch/mips/sibyte/swarm/setup.c | 15 +++++++--- arch/mips/sni/time.c | 5 ++-- arch/powerpc/kernel/time.c | 7 +++-- arch/s390/kernel/time.c | 22 +++------------ arch/sh/kernel/time.c | 6 ++-- arch/x86/kernel/rtc.c | 5 ++-- arch/xtensa/kernel/time.c | 5 ++-- include/linux/time.h | 2 +- kernel/time/timekeeping.c | 52 +++++++++++++++++++---------------- 16 files changed, 83 insertions(+), 74 deletions(-) (limited to 'kernel') diff --git a/arch/m68knommu/kernel/time.c b/arch/m68knommu/kernel/time.c index d182b2f72211..68432248515c 100644 --- a/arch/m68knommu/kernel/time.c +++ b/arch/m68knommu/kernel/time.c @@ -72,9 +72,10 @@ static unsigned long read_rtc_mmss(void) return mktime(year, mon, day, hour, min, sec);; } -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { - return read_rtc_mmss(); + ts->tv_sec = read_rtc_mmss(); + ts->tv_nsec = 0; } int update_persistent_clock(struct timespec now) diff --git a/arch/mips/dec/time.c b/arch/mips/dec/time.c index 463136e6685a..02f505f23c32 100644 --- a/arch/mips/dec/time.c +++ b/arch/mips/dec/time.c @@ -18,7 +18,7 @@ #include #include -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { unsigned int year, mon, day, hour, min, sec, real_year; unsigned long flags; @@ -53,7 +53,8 @@ unsigned long read_persistent_clock(void) year += real_year - 72 + 2000; - return mktime(year, mon, day, hour, min, sec); + ts->tv_sec = mktime(year, mon, day, hour, min, sec); + ts->tv_nsec = 0; } /* diff --git a/arch/mips/lasat/ds1603.c b/arch/mips/lasat/ds1603.c index 52cb1436a12a..c6fd96ff118d 100644 --- a/arch/mips/lasat/ds1603.c +++ b/arch/mips/lasat/ds1603.c @@ -135,7 +135,7 @@ static void rtc_end_op(void) lasat_ndelay(1000); } -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { unsigned long word; unsigned long flags; @@ -147,7 +147,8 @@ unsigned long read_persistent_clock(void) rtc_end_op(); spin_unlock_irqrestore(&rtc_lock, flags); - return word; + ts->tv_sec = word; + ts->tv_nsec = 0; } int rtc_mips_set_mmss(unsigned long time) diff --git a/arch/mips/lasat/sysctl.c b/arch/mips/lasat/sysctl.c index 8f88886feb12..3f04d4c406b7 100644 --- a/arch/mips/lasat/sysctl.c +++ b/arch/mips/lasat/sysctl.c @@ -92,10 +92,12 @@ static int rtctmp; int proc_dolasatrtc(ctl_table *table, int write, struct file *filp, void *buffer, size_t *lenp, loff_t *ppos) { + struct timespec ts; int r; if (!write) { - rtctmp = read_persistent_clock(); + read_persistent_clock(&ts); + rtctmp = ts.tv_sec; /* check for time < 0 and set to 0 */ if (rtctmp < 0) rtctmp = 0; @@ -134,9 +136,11 @@ int sysctl_lasat_rtc(ctl_table *table, void *oldval, size_t *oldlenp, void *newval, size_t newlen) { + struct timespec ts; int r; - rtctmp = read_persistent_clock(); + read_persistent_clock(&ts); + rtctmp = ts.tv_sec; if (rtctmp < 0) rtctmp = 0; r = sysctl_intvec(table, oldval, oldlenp, newval, newlen); diff --git a/arch/mips/lemote/lm2e/setup.c b/arch/mips/lemote/lm2e/setup.c index ebd6ceaef2fd..24b355df6127 100644 --- a/arch/mips/lemote/lm2e/setup.c +++ b/arch/mips/lemote/lm2e/setup.c @@ -54,9 +54,10 @@ void __init plat_time_init(void) mips_hpt_frequency = cpu_clock_freq / 2; } -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { - return mc146818_get_cmos_time(); + ts->tv_sec = mc146818_get_cmos_time(); + ts->tv_nsec = 0; } void (*__wbflush)(void); diff --git a/arch/mips/mti-malta/malta-time.c b/arch/mips/mti-malta/malta-time.c index 0b97d47691fc..3c6f190aa61c 100644 --- a/arch/mips/mti-malta/malta-time.c +++ b/arch/mips/mti-malta/malta-time.c @@ -100,9 +100,10 @@ static unsigned int __init estimate_cpu_frequency(void) return count; } -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { - return mc146818_get_cmos_time(); + ts->tv_sec = mc146818_get_cmos_time(); + ts->tv_nsec = 0; } static void __init plat_perf_setup(void) diff --git a/arch/mips/pmc-sierra/yosemite/setup.c b/arch/mips/pmc-sierra/yosemite/setup.c index 2d3c0dca275d..3498ac9c35af 100644 --- a/arch/mips/pmc-sierra/yosemite/setup.c +++ b/arch/mips/pmc-sierra/yosemite/setup.c @@ -70,7 +70,7 @@ void __init bus_error_init(void) } -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { unsigned int year, month, day, hour, min, sec; unsigned long flags; @@ -92,7 +92,8 @@ unsigned long read_persistent_clock(void) m48t37_base->control = 0x00; spin_unlock_irqrestore(&rtc_lock, flags); - return mktime(year, month, day, hour, min, sec); + ts->tv_sec = mktime(year, month, day, hour, min, sec); + ts->tv_nsec = 0; } int rtc_mips_set_time(unsigned long tim) diff --git a/arch/mips/sibyte/swarm/setup.c b/arch/mips/sibyte/swarm/setup.c index 672e45d495a9..623ffc933c4c 100644 --- a/arch/mips/sibyte/swarm/setup.c +++ b/arch/mips/sibyte/swarm/setup.c @@ -87,19 +87,26 @@ enum swarm_rtc_type { enum swarm_rtc_type swarm_rtc_type; -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { + unsigned long sec; + switch (swarm_rtc_type) { case RTC_XICOR: - return xicor_get_time(); + sec = xicor_get_time(); + break; case RTC_M4LT81: - return m41t81_get_time(); + sec = m41t81_get_time(); + break; case RTC_NONE: default: - return mktime(2000, 1, 1, 0, 0, 0); + sec = mktime(2000, 1, 1, 0, 0, 0); + break; } + ts->tv_sec = sec; + tv->tv_nsec = 0; } int rtc_mips_set_time(unsigned long sec) diff --git a/arch/mips/sni/time.c b/arch/mips/sni/time.c index 0d9ec1a5c24a..62df6a598e0a 100644 --- a/arch/mips/sni/time.c +++ b/arch/mips/sni/time.c @@ -182,7 +182,8 @@ void __init plat_time_init(void) setup_pit_timer(); } -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { - return -1; + ts->tv_sec = -1; + ts->tv_nsec = 0; } diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index eae4511ceeac..ad63f30fe3da 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -769,7 +769,7 @@ int update_persistent_clock(struct timespec now) return ppc_md.set_rtc_time(&tm); } -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { struct rtc_time tm; static int first = 1; @@ -787,8 +787,9 @@ unsigned long read_persistent_clock(void) if (!ppc_md.get_rtc_time) return 0; ppc_md.get_rtc_time(&tm); - return mktime(tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday, - tm.tm_hour, tm.tm_min, tm.tm_sec); + ts->tv_sec = mktime(tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday, + tm.tm_hour, tm.tm_min, tm.tm_sec); + ts->tv_nsec = 0; } /* clocksource code */ diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index e76c2e7a8b9a..a94ec48587b4 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -182,12 +182,9 @@ static void timing_alert_interrupt(__u16 code) static void etr_reset(void); static void stp_reset(void); -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { - struct timespec ts; - - tod_to_timeval(get_clock() - TOD_UNIX_EPOCH, &ts); - return ts.tv_sec; + tod_to_timeval(get_clock() - TOD_UNIX_EPOCH, ts); } static cycle_t read_tod_clock(struct clocksource *cs) @@ -248,7 +245,6 @@ void __init time_init(void) { struct timespec ts; unsigned long flags; - cycle_t now; /* Reset time synchronization interfaces. */ etr_reset(); @@ -266,20 +262,10 @@ void __init time_init(void) panic("Could not register TOD clock source"); /* - * The TOD clock is an accurate clock. The xtime should be - * initialized in a way that the difference between TOD and - * xtime is reasonably small. Too bad that timekeeping_init - * sets xtime.tv_nsec to zero. In addition the clock source - * change from the jiffies clock source to the TOD clock - * source add another error of up to 1/HZ second. The same - * function sets wall_to_monotonic to a value that is too - * small for /proc/uptime to be accurate. - * Reset xtime and wall_to_monotonic to sane values. + * Reset wall_to_monotonic to the initial timestamp created + * in head.S to get a precise value in /proc/uptime. */ write_seqlock_irqsave(&xtime_lock, flags); - now = get_clock(); - tod_to_timeval(now - TOD_UNIX_EPOCH, &xtime); - clocksource_tod.cycle_last = now; tod_to_timeval(sched_clock_base_cc - TOD_UNIX_EPOCH, &ts); set_normalized_timespec(&wall_to_monotonic, -ts.tv_sec, -ts.tv_nsec); write_sequnlock_irqrestore(&xtime_lock, flags); diff --git a/arch/sh/kernel/time.c b/arch/sh/kernel/time.c index 9b352a1e3fb4..3f4706aa975e 100644 --- a/arch/sh/kernel/time.c +++ b/arch/sh/kernel/time.c @@ -39,11 +39,9 @@ void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time; int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time; #ifdef CONFIG_GENERIC_CMOS_UPDATE -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { - struct timespec tv; - rtc_sh_get_time(&tv); - return tv.tv_sec; + rtc_sh_get_time(&ts); } int update_persistent_clock(struct timespec now) diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c index 5d465b207e72..bf67dcb4a44c 100644 --- a/arch/x86/kernel/rtc.c +++ b/arch/x86/kernel/rtc.c @@ -178,7 +178,7 @@ static int set_rtc_mmss(unsigned long nowtime) } /* not static: needed by APM */ -unsigned long read_persistent_clock(void) +void read_persistent_clock(struct timespec *ts) { unsigned long retval, flags; @@ -186,7 +186,8 @@ unsigned long read_persistent_clock(void) retval = get_wallclock(); spin_unlock_irqrestore(&rtc_lock, flags); - return retval; + ts->tv_sec = retval; + ts->tv_nsec = 0; } int update_persistent_clock(struct timespec now) diff --git a/arch/xtensa/kernel/time.c b/arch/xtensa/kernel/time.c index 8848120d291b..19085ff0484a 100644 --- a/arch/xtensa/kernel/time.c +++ b/arch/xtensa/kernel/time.c @@ -59,9 +59,8 @@ static struct irqaction timer_irqaction = { void __init time_init(void) { - xtime.tv_nsec = 0; - xtime.tv_sec = read_persistent_clock(); - + /* FIXME: xtime&wall_to_monotonic are set in timekeeping_init. */ + read_persistent_clock(&xtime); set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec); diff --git a/include/linux/time.h b/include/linux/time.h index e7c844558884..53a3216f0d1b 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -101,7 +101,7 @@ extern struct timespec xtime; extern struct timespec wall_to_monotonic; extern seqlock_t xtime_lock; -extern unsigned long read_persistent_clock(void); +extern void read_persistent_clock(struct timespec *ts); extern int update_persistent_clock(struct timespec now); extern int no_sync_cmos_clock __read_mostly; void timekeeping_init(void); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 41579e7fcf9d..f1a21ce491e6 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -154,7 +154,7 @@ __cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock); */ struct timespec xtime __attribute__ ((aligned (16))); struct timespec wall_to_monotonic __attribute__ ((aligned (16))); -static unsigned long total_sleep_time; /* seconds */ +static struct timespec total_sleep_time; /* * The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. @@ -487,17 +487,18 @@ int timekeeping_valid_for_hres(void) } /** - * read_persistent_clock - Return time in seconds from the persistent clock. + * read_persistent_clock - Return time from the persistent clock. * * Weak dummy function for arches that do not yet support it. - * Returns seconds from epoch using the battery backed persistent clock. - * Returns zero if unsupported. + * Reads the time from the battery backed persistent clock. + * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported. * * XXX - Do be sure to remove it once all arches implement it. */ -unsigned long __attribute__((weak)) read_persistent_clock(void) +void __attribute__((weak)) read_persistent_clock(struct timespec *ts) { - return 0; + ts->tv_sec = 0; + ts->tv_nsec = 0; } /* @@ -507,7 +508,9 @@ void __init timekeeping_init(void) { struct clocksource *clock; unsigned long flags; - unsigned long sec = read_persistent_clock(); + struct timespec now; + + read_persistent_clock(&now); write_seqlock_irqsave(&xtime_lock, flags); @@ -518,19 +521,20 @@ void __init timekeeping_init(void) clock->enable(clock); timekeeper_setup_internals(clock); - xtime.tv_sec = sec; - xtime.tv_nsec = 0; + xtime.tv_sec = now.tv_sec; + xtime.tv_nsec = now.tv_nsec; raw_time.tv_sec = 0; raw_time.tv_nsec = 0; set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec); update_xtime_cache(0); - total_sleep_time = 0; + total_sleep_time.tv_sec = 0; + total_sleep_time.tv_nsec = 0; write_sequnlock_irqrestore(&xtime_lock, flags); } /* time in seconds when suspend began */ -static unsigned long timekeeping_suspend_time; +static struct timespec timekeeping_suspend_time; /** * timekeeping_resume - Resumes the generic timekeeping subsystem. @@ -543,18 +547,19 @@ static unsigned long timekeeping_suspend_time; static int timekeeping_resume(struct sys_device *dev) { unsigned long flags; - unsigned long now = read_persistent_clock(); + struct timespec ts; + + read_persistent_clock(&ts); clocksource_resume(); write_seqlock_irqsave(&xtime_lock, flags); - if (now && (now > timekeeping_suspend_time)) { - unsigned long sleep_length = now - timekeeping_suspend_time; - - xtime.tv_sec += sleep_length; - wall_to_monotonic.tv_sec -= sleep_length; - total_sleep_time += sleep_length; + if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) { + ts = timespec_sub(ts, timekeeping_suspend_time); + xtime = timespec_add_safe(xtime, ts); + wall_to_monotonic = timespec_sub(wall_to_monotonic, ts); + total_sleep_time = timespec_add_safe(total_sleep_time, ts); } update_xtime_cache(0); /* re-base the last cycle value */ @@ -577,7 +582,7 @@ static int timekeeping_suspend(struct sys_device *dev, pm_message_t state) { unsigned long flags; - timekeeping_suspend_time = read_persistent_clock(); + read_persistent_clock(&timekeeping_suspend_time); write_seqlock_irqsave(&xtime_lock, flags); timekeeping_forward_now(); @@ -801,9 +806,10 @@ void update_wall_time(void) */ void getboottime(struct timespec *ts) { - set_normalized_timespec(ts, - - (wall_to_monotonic.tv_sec + total_sleep_time), - - wall_to_monotonic.tv_nsec); + struct timespec boottime; + + boottime = timespec_add_safe(wall_to_monotonic, total_sleep_time); + set_normalized_timespec(ts, -boottime.tv_sec, -boottime.tv_nsec); } /** @@ -812,7 +818,7 @@ void getboottime(struct timespec *ts) */ void monotonic_to_bootbased(struct timespec *ts) { - ts->tv_sec += total_sleep_time; + *ts = timespec_add_safe(*ts, total_sleep_time); } unsigned long get_seconds(void) -- cgit v1.2.3 From 23970e389e9cee43c4b41023935e1417271708b2 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 14 Aug 2009 15:47:32 +0200 Subject: timekeeping: Introduce read_boot_clock Add the new function read_boot_clock to get the exact time the system has been started. For architectures without support for exact boot time a new weak function is added that returns 0. Use the exact boot time to initialize wall_to_monotonic, or xtime if the read_boot_clock returned 0. Signed-off-by: Martin Schwidefsky Cc: Ingo Molnar Acked-by: John Stultz Cc: Daniel Walker LKML-Reference: <20090814134811.296703241@de.ibm.com> Signed-off-by: Thomas Gleixner --- arch/s390/kernel/time.c | 17 +++++------------ include/linux/time.h | 1 + kernel/time/timekeeping.c | 24 ++++++++++++++++++++++-- 3 files changed, 28 insertions(+), 14 deletions(-) (limited to 'kernel') diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index a94ec48587b4..6bff1a1d9060 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -187,6 +187,11 @@ void read_persistent_clock(struct timespec *ts) tod_to_timeval(get_clock() - TOD_UNIX_EPOCH, ts); } +void read_boot_clock(struct timespec *ts) +{ + tod_to_timeval(sched_clock_base_cc - TOD_UNIX_EPOCH, ts); +} + static cycle_t read_tod_clock(struct clocksource *cs) { return get_clock(); @@ -243,9 +248,6 @@ void update_vsyscall_tz(void) */ void __init time_init(void) { - struct timespec ts; - unsigned long flags; - /* Reset time synchronization interfaces. */ etr_reset(); stp_reset(); @@ -261,15 +263,6 @@ void __init time_init(void) if (clocksource_register(&clocksource_tod) != 0) panic("Could not register TOD clock source"); - /* - * Reset wall_to_monotonic to the initial timestamp created - * in head.S to get a precise value in /proc/uptime. - */ - write_seqlock_irqsave(&xtime_lock, flags); - tod_to_timeval(sched_clock_base_cc - TOD_UNIX_EPOCH, &ts); - set_normalized_timespec(&wall_to_monotonic, -ts.tv_sec, -ts.tv_nsec); - write_sequnlock_irqrestore(&xtime_lock, flags); - /* Enable TOD clock interrupts on the boot cpu. */ init_cpu_timer(); diff --git a/include/linux/time.h b/include/linux/time.h index 53a3216f0d1b..f505988398e6 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -102,6 +102,7 @@ extern struct timespec wall_to_monotonic; extern seqlock_t xtime_lock; extern void read_persistent_clock(struct timespec *ts); +extern void read_boot_clock(struct timespec *ts); extern int update_persistent_clock(struct timespec now); extern int no_sync_cmos_clock __read_mostly; void timekeeping_init(void); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index f1a21ce491e6..15e06defca55 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -501,6 +501,21 @@ void __attribute__((weak)) read_persistent_clock(struct timespec *ts) ts->tv_nsec = 0; } +/** + * read_boot_clock - Return time of the system start. + * + * Weak dummy function for arches that do not yet support it. + * Function to read the exact time the system has been started. + * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported. + * + * XXX - Do be sure to remove it once all arches implement it. + */ +void __attribute__((weak)) read_boot_clock(struct timespec *ts) +{ + ts->tv_sec = 0; + ts->tv_nsec = 0; +} + /* * timekeeping_init - Initializes the clocksource and common timekeeping values */ @@ -508,9 +523,10 @@ void __init timekeeping_init(void) { struct clocksource *clock; unsigned long flags; - struct timespec now; + struct timespec now, boot; read_persistent_clock(&now); + read_boot_clock(&boot); write_seqlock_irqsave(&xtime_lock, flags); @@ -525,8 +541,12 @@ void __init timekeeping_init(void) xtime.tv_nsec = now.tv_nsec; raw_time.tv_sec = 0; raw_time.tv_nsec = 0; + if (boot.tv_sec == 0 && boot.tv_nsec == 0) { + boot.tv_sec = xtime.tv_sec; + boot.tv_nsec = xtime.tv_nsec; + } set_normalized_timespec(&wall_to_monotonic, - -xtime.tv_sec, -xtime.tv_nsec); + -boot.tv_sec, -boot.tv_nsec); update_xtime_cache(0); total_sleep_time.tv_sec = 0; total_sleep_time.tv_nsec = 0; -- cgit v1.2.3 From 6ea41d252f35465a2308a4038a323b6b07de06f6 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sat, 15 Aug 2009 13:20:42 +0200 Subject: clocksource: Call clocksource_change_rating() outside of watchdog_lock The changes to the watchdog logic introduced a lock inversion between watchdog_lock and clocksource_mutex. Change the rating outside of watchdog_lock to avoid it. Signed-off-by: Thomas Gleixner --- kernel/time/clocksource.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index a1657b5fdeb9..02dc22d888fe 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -307,16 +307,23 @@ static void clocksource_watchdog_work(struct work_struct *work) { struct clocksource *cs, *tmp; unsigned long flags; + LIST_HEAD(unstable); spin_lock_irqsave(&watchdog_lock, flags); list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list) if (cs->flags & CLOCK_SOURCE_UNSTABLE) { list_del_init(&cs->wd_list); - clocksource_change_rating(cs, 0); + list_add(&cs->wd_list, &unstable); } /* Check if the watchdog timer needs to be stopped. */ clocksource_stop_watchdog(); - spin_unlock(&watchdog_lock); + spin_unlock_irqrestore(&watchdog_lock, flags); + + /* Needs to be done outside of watchdog lock */ + list_for_each_entry_safe(cs, tmp, &unstable, wd_list) { + list_del_init(&cs->wd_list); + clocksource_change_rating(cs, 0); + } } #else /* CONFIG_CLOCKSOURCE_WATCHDOG */ -- cgit v1.2.3 From de481560eb0bd9d940b90311eba85711e4b1150b Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 30 Apr 2009 12:32:04 -0400 Subject: kconfig: keep config.gz around even if CONFIG_IKCONFIG_PROC is not set If CONFIG_IKCONFIG is set but CONFIG_IKCONFIG_PROC is not, then gcc will optimize the config.gz out, because nobody uses it. This patch adds "__used" to the config.gz data to keep it around so that code like extract-ikconfig can still find it. [ Impact: allow extract-ikconfig to find config.gz ] Signed-off-by: Steven Rostedt --- kernel/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/Makefile b/kernel/Makefile index 2093a691f1c2..d0c84e6bf50a 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -119,7 +119,7 @@ $(obj)/config_data.gz: .config FORCE $(call if_changed,gzip) quiet_cmd_ikconfiggz = IKCFG $@ - cmd_ikconfiggz = (echo "static const char kernel_config_data[] = MAGIC_START"; cat $< | scripts/bin2c; echo "MAGIC_END;") > $@ + cmd_ikconfiggz = (echo "static const char kernel_config_data[] __used = MAGIC_START"; cat $< | scripts/bin2c; echo "MAGIC_END;") > $@ targets += config_data.h $(obj)/config_data.h: $(obj)/config_data.gz FORCE $(call if_changed,ikconfiggz) -- cgit v1.2.3 From d0981a1b21a03866c8da7f44e35e389c2e0d6061 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 19 Aug 2009 11:26:09 +0200 Subject: clocksource: Protect the watchdog rating changes with clocksource_mutex Martin pointed out that commit 6ea41d2529 (clocksource: Call clocksource_change_rating() outside of watchdog_lock) has a theoretical reference count problem. The calls to clocksource_change_rating() are now done outside of the clocksource mutex and outside of the watchdog lock. A concurrent clocksource_unregister() could remove the clock. Split out the code which changes the rating from clocksource_change_rating() into __clocksource_change_rating(). Protect the clocksource_watchdog_work() code sequence with the clocksource_mutex() and call __clocksource_change_rating(). LKML-Reference: Signed-off-by: Thomas Gleixner Cc: Martin Schwidefsky --- kernel/time/clocksource.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) (limited to 'kernel') diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 02dc22d888fe..c6bff11f7957 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -131,6 +131,7 @@ static cycle_t watchdog_last; static int watchdog_running; static void clocksource_watchdog_work(struct work_struct *work); +static void __clocksource_change_rating(struct clocksource *cs, int rating); /* * Interval: 0.5sec Threshold: 0.0625s @@ -309,6 +310,7 @@ static void clocksource_watchdog_work(struct work_struct *work) unsigned long flags; LIST_HEAD(unstable); + mutex_lock(&clocksource_mutex); spin_lock_irqsave(&watchdog_lock, flags); list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list) if (cs->flags & CLOCK_SOURCE_UNSTABLE) { @@ -322,8 +324,9 @@ static void clocksource_watchdog_work(struct work_struct *work) /* Needs to be done outside of watchdog lock */ list_for_each_entry_safe(cs, tmp, &unstable, wd_list) { list_del_init(&cs->wd_list); - clocksource_change_rating(cs, 0); + __clocksource_change_rating(cs, 0); } + mutex_unlock(&clocksource_mutex); } #else /* CONFIG_CLOCKSOURCE_WATCHDOG */ @@ -470,16 +473,21 @@ int clocksource_register(struct clocksource *cs) } EXPORT_SYMBOL(clocksource_register); +static void __clocksource_change_rating(struct clocksource *cs, int rating) +{ + list_del(&cs->list); + cs->rating = rating; + clocksource_enqueue(cs); + clocksource_select(); +} + /** * clocksource_change_rating - Change the rating of a registered clocksource */ void clocksource_change_rating(struct clocksource *cs, int rating) { mutex_lock(&clocksource_mutex); - list_del(&cs->list); - cs->rating = rating; - clocksource_enqueue(cs); - clocksource_select(); + __clocksource_change_rating(cs, rating); mutex_unlock(&clocksource_mutex); } EXPORT_SYMBOL(clocksource_change_rating); -- cgit v1.2.3 From 01548f4d3e8e94caf323a4f664eb347fd34a34ab Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Tue, 18 Aug 2009 17:09:42 +0200 Subject: clocksource: Avoid clocksource watchdog circular locking dependency stop_machine from a multithreaded workqueue is not allowed because of a circular locking dependency between cpu_down and the workqueue execution. Use a kernel thread to do the clocksource downgrade. Signed-off-by: Martin Schwidefsky Cc: Peter Zijlstra Cc: john stultz LKML-Reference: <20090818170942.3ab80c91@skybase> Signed-off-by: Thomas Gleixner --- kernel/time/clocksource.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index c6bff11f7957..e0c86ad6e9fb 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -29,6 +29,7 @@ #include #include /* for spin_unlock_irq() using preempt_count() m68k */ #include +#include void timecounter_init(struct timecounter *tc, const struct cyclecounter *cc, @@ -130,7 +131,7 @@ static DEFINE_SPINLOCK(watchdog_lock); static cycle_t watchdog_last; static int watchdog_running; -static void clocksource_watchdog_work(struct work_struct *work); +static int clocksource_watchdog_kthread(void *data); static void __clocksource_change_rating(struct clocksource *cs, int rating); /* @@ -139,6 +140,15 @@ static void __clocksource_change_rating(struct clocksource *cs, int rating); #define WATCHDOG_INTERVAL (HZ >> 1) #define WATCHDOG_THRESHOLD (NSEC_PER_SEC >> 4) +static void clocksource_watchdog_work(struct work_struct *work) +{ + /* + * If kthread_run fails the next watchdog scan over the + * watchdog_list will find the unstable clock again. + */ + kthread_run(clocksource_watchdog_kthread, NULL, "kwatchdog"); +} + static void clocksource_unstable(struct clocksource *cs, int64_t delta) { printk(KERN_WARNING "Clocksource %s unstable (delta = %Ld ns)\n", @@ -167,8 +177,10 @@ static void clocksource_watchdog(unsigned long data) list_for_each_entry(cs, &watchdog_list, wd_list) { /* Clocksource already marked unstable? */ - if (cs->flags & CLOCK_SOURCE_UNSTABLE) + if (cs->flags & CLOCK_SOURCE_UNSTABLE) { + schedule_work(&watchdog_work); continue; + } csnow = cs->read(cs); @@ -304,7 +316,7 @@ static void clocksource_dequeue_watchdog(struct clocksource *cs) spin_unlock_irqrestore(&watchdog_lock, flags); } -static void clocksource_watchdog_work(struct work_struct *work) +static int clocksource_watchdog_kthread(void *data) { struct clocksource *cs, *tmp; unsigned long flags; @@ -327,6 +339,7 @@ static void clocksource_watchdog_work(struct work_struct *work) __clocksource_change_rating(cs, 0); } mutex_unlock(&clocksource_mutex); + return 0; } #else /* CONFIG_CLOCKSOURCE_WATCHDOG */ -- cgit v1.2.3 From a15098c90df1ac2b1bfe1d33dd1c47063213aa9a Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Sun, 9 Aug 2009 19:02:51 +0000 Subject: powerpc: Enable GCOV Make it possible to enable GCOV code coverage measurement on powerpc. Lightly tested on 64-bit, seems to work as expected. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/Makefile | 7 +++++++ arch/powerpc/kernel/vdso32/Makefile | 1 + arch/powerpc/kernel/vdso64/Makefile | 2 ++ arch/powerpc/xmon/Makefile | 2 ++ kernel/gcov/Kconfig | 2 +- 5 files changed, 13 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 035946f9d5fb..720e8c3b8e94 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -115,6 +115,13 @@ ifneq ($(CONFIG_XMON)$(CONFIG_KEXEC),) obj-y += ppc_save_regs.o endif +# Disable GCOV in odd or sensitive code +GCOV_PROFILE_prom_init.o := n +GCOV_PROFILE_ftrace.o := n +GCOV_PROFILE_machine_kexec_64.o := n +GCOV_PROFILE_machine_kexec_32.o := n +GCOV_PROFILE_kprobes.o := n + extra-$(CONFIG_PPC_FPU) += fpu.o extra-$(CONFIG_ALTIVEC) += vector.o extra-$(CONFIG_PPC64) += entry_64.o diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile index c3d57bd01a88..b54b81688132 100644 --- a/arch/powerpc/kernel/vdso32/Makefile +++ b/arch/powerpc/kernel/vdso32/Makefile @@ -12,6 +12,7 @@ endif targets := $(obj-vdso32) vdso32.so vdso32.so.dbg obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32)) +GCOV_PROFILE := n EXTRA_CFLAGS := -shared -fno-common -fno-builtin EXTRA_CFLAGS += -nostdlib -Wl,-soname=linux-vdso32.so.1 \ diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile index fa7f1b8f3e50..dd0c8e936775 100644 --- a/arch/powerpc/kernel/vdso64/Makefile +++ b/arch/powerpc/kernel/vdso64/Makefile @@ -7,6 +7,8 @@ obj-vdso64 = sigtramp.o gettimeofday.o datapage.o cacheflush.o note.o targets := $(obj-vdso64) vdso64.so vdso64.so.dbg obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64)) +GCOV_PROFILE := n + EXTRA_CFLAGS := -shared -fno-common -fno-builtin EXTRA_CFLAGS += -nostdlib -Wl,-soname=linux-vdso64.so.1 \ $(call ld-option, -Wl$(comma)--hash-style=sysv) diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile index 85ab97ab840a..faa81b6a6612 100644 --- a/arch/powerpc/xmon/Makefile +++ b/arch/powerpc/xmon/Makefile @@ -2,6 +2,8 @@ subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror +GCOV_PROFILE := n + ifdef CONFIG_PPC64 EXTRA_CFLAGS += -mno-minimal-toc endif diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig index 22e9dcfaa3d3..654efd09f6a9 100644 --- a/kernel/gcov/Kconfig +++ b/kernel/gcov/Kconfig @@ -34,7 +34,7 @@ config GCOV_KERNEL config GCOV_PROFILE_ALL bool "Profile entire Kernel" depends on GCOV_KERNEL - depends on S390 || X86 + depends on S390 || X86 || (PPC && EXPERIMENTAL) default n ---help--- This options activates profiling for the entire kernel. -- cgit v1.2.3 From da15cfdae03351c689736f8d142618592e3cebc3 Mon Sep 17 00:00:00 2001 From: john stultz Date: Wed, 19 Aug 2009 19:13:34 -0700 Subject: time: Introduce CLOCK_REALTIME_COARSE After talking with some application writers who want very fast, but not fine-grained timestamps, I decided to try to implement new clock_ids to clock_gettime(): CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE which returns the time at the last tick. This is very fast as we don't have to access any hardware (which can be very painful if you're using something like the acpi_pm clocksource), and we can even use the vdso clock_gettime() method to avoid the syscall. The only trade off is you only get low-res tick grained time resolution. This isn't a new idea, I know Ingo has a patch in the -rt tree that made the vsyscall gettimeofday() return coarse grained time when the vsyscall64 sysctrl was set to 2. However this affects all applications on a system. With this method, applications can choose the proper speed/granularity trade-off for themselves. Signed-off-by: John Stultz Cc: Andi Kleen Cc: nikolag@ca.ibm.com Cc: Darren Hart Cc: arjan@infradead.org Cc: jonathan@jonmasters.org LKML-Reference: <1250734414.6897.5.camel@localhost.localdomain> Signed-off-by: Thomas Gleixner --- arch/x86/include/asm/vgtod.h | 1 + arch/x86/kernel/vsyscall_64.c | 1 + arch/x86/vdso/vclock_gettime.c | 39 ++++++++++++++++++++++++++++++++++++--- include/linux/time.h | 4 ++++ kernel/posix-timers.c | 35 +++++++++++++++++++++++++++++++++++ kernel/time/timekeeping.c | 21 +++++++++++++++++++++ 6 files changed, 98 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/arch/x86/include/asm/vgtod.h b/arch/x86/include/asm/vgtod.h index dc27a69e5d2a..3d61e204826f 100644 --- a/arch/x86/include/asm/vgtod.h +++ b/arch/x86/include/asm/vgtod.h @@ -21,6 +21,7 @@ struct vsyscall_gtod_data { u32 shift; } clock; struct timespec wall_to_monotonic; + struct timespec wall_time_coarse; }; extern struct vsyscall_gtod_data __vsyscall_gtod_data __section_vsyscall_gtod_data; diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index 25ee06a80aad..cf53a78e2dcf 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -87,6 +87,7 @@ void update_vsyscall(struct timespec *wall_time, struct clocksource *clock) vsyscall_gtod_data.wall_time_sec = wall_time->tv_sec; vsyscall_gtod_data.wall_time_nsec = wall_time->tv_nsec; vsyscall_gtod_data.wall_to_monotonic = wall_to_monotonic; + vsyscall_gtod_data.wall_time_coarse = __current_kernel_time(); write_sequnlock_irqrestore(&vsyscall_gtod_data.lock, flags); } diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c index 6a40b78b46aa..ee55754cc3c5 100644 --- a/arch/x86/vdso/vclock_gettime.c +++ b/arch/x86/vdso/vclock_gettime.c @@ -86,14 +86,47 @@ notrace static noinline int do_monotonic(struct timespec *ts) return 0; } +notrace static noinline int do_realtime_coarse(struct timespec *ts) +{ + unsigned long seq; + do { + seq = read_seqbegin(>od->lock); + ts->tv_sec = gtod->wall_time_coarse.tv_sec; + ts->tv_nsec = gtod->wall_time_coarse.tv_nsec; + } while (unlikely(read_seqretry(>od->lock, seq))); + return 0; +} + +notrace static noinline int do_monotonic_coarse(struct timespec *ts) +{ + unsigned long seq, ns, secs; + do { + seq = read_seqbegin(>od->lock); + secs = gtod->wall_time_coarse.tv_sec; + ns = gtod->wall_time_coarse.tv_nsec; + secs += gtod->wall_to_monotonic.tv_sec; + ns += gtod->wall_to_monotonic.tv_nsec; + } while (unlikely(read_seqretry(>od->lock, seq))); + vset_normalized_timespec(ts, secs, ns); + return 0; +} + notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts) { - if (likely(gtod->sysctl_enabled && gtod->clock.vread)) + if (likely(gtod->sysctl_enabled)) switch (clock) { case CLOCK_REALTIME: - return do_realtime(ts); + if (likely(gtod->clock.vread)) + return do_realtime(ts); + break; case CLOCK_MONOTONIC: - return do_monotonic(ts); + if (likely(gtod->clock.vread)) + return do_monotonic(ts); + break; + case CLOCK_REALTIME_COARSE: + return do_realtime_coarse(ts); + case CLOCK_MONOTONIC_COARSE: + return do_monotonic_coarse(ts); } return vdso_fallback_gettime(clock, ts); } diff --git a/include/linux/time.h b/include/linux/time.h index f505988398e6..256232f7e5e6 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -110,6 +110,8 @@ extern int timekeeping_suspended; unsigned long get_seconds(void); struct timespec current_kernel_time(void); +struct timespec __current_kernel_time(void); /* does not hold xtime_lock */ +struct timespec get_monotonic_coarse(void); #define CURRENT_TIME (current_kernel_time()) #define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 }) @@ -243,6 +245,8 @@ struct itimerval { #define CLOCK_PROCESS_CPUTIME_ID 2 #define CLOCK_THREAD_CPUTIME_ID 3 #define CLOCK_MONOTONIC_RAW 4 +#define CLOCK_REALTIME_COARSE 5 +#define CLOCK_MONOTONIC_COARSE 6 /* * The IDs of various hardware clocks: diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c index d089d052c4a9..495440779ce3 100644 --- a/kernel/posix-timers.c +++ b/kernel/posix-timers.c @@ -242,6 +242,25 @@ static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp) return 0; } + +static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec *tp) +{ + *tp = current_kernel_time(); + return 0; +} + +static int posix_get_monotonic_coarse(clockid_t which_clock, + struct timespec *tp) +{ + *tp = get_monotonic_coarse(); + return 0; +} + +int posix_get_coarse_res(const clockid_t which_clock, struct timespec *tp) +{ + *tp = ktime_to_timespec(KTIME_LOW_RES); + return 0; +} /* * Initialize everything, well, just everything in Posix clocks/timers ;) */ @@ -262,10 +281,26 @@ static __init int init_posix_timers(void) .timer_create = no_timer_create, .nsleep = no_nsleep, }; + struct k_clock clock_realtime_coarse = { + .clock_getres = posix_get_coarse_res, + .clock_get = posix_get_realtime_coarse, + .clock_set = do_posix_clock_nosettime, + .timer_create = no_timer_create, + .nsleep = no_nsleep, + }; + struct k_clock clock_monotonic_coarse = { + .clock_getres = posix_get_coarse_res, + .clock_get = posix_get_monotonic_coarse, + .clock_set = do_posix_clock_nosettime, + .timer_create = no_timer_create, + .nsleep = no_nsleep, + }; register_posix_clock(CLOCK_REALTIME, &clock_realtime); register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic); register_posix_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw); + register_posix_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse); + register_posix_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse); posix_timers_cache = kmem_cache_create("posix_timers_cache", sizeof (struct k_itimer), 0, SLAB_PANIC, diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 15e06defca55..03cbeb34d141 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -847,6 +847,10 @@ unsigned long get_seconds(void) } EXPORT_SYMBOL(get_seconds); +struct timespec __current_kernel_time(void) +{ + return xtime_cache; +} struct timespec current_kernel_time(void) { @@ -862,3 +866,20 @@ struct timespec current_kernel_time(void) return now; } EXPORT_SYMBOL(current_kernel_time); + +struct timespec get_monotonic_coarse(void) +{ + struct timespec now, mono; + unsigned long seq; + + do { + seq = read_seqbegin(&xtime_lock); + + now = xtime_cache; + mono = wall_to_monotonic; + } while (read_seqretry(&xtime_lock, seq)); + + set_normalized_timespec(&now, now.tv_sec + mono.tv_sec, + now.tv_nsec + mono.tv_nsec); + return now; +} -- cgit v1.2.3 From 269c861baa2fe7c114c3bc7831292758d29eb336 Mon Sep 17 00:00:00 2001 From: Suresh Siddha Date: Wed, 19 Aug 2009 18:05:35 -0700 Subject: generic-ipi: Allow cpus not yet online to call smp_call_function with irqs disabled Because of deadlock possiblities smp_call_function() is not allowed to be called with interrupts disabled. Add an exception for the cpu not yet online, as no one else can send smp call function interrupt to this cpu that is not yet online and as such deadlock condition is not possible. Signed-off-by: Suresh Siddha Acked-by: Nick Piggin Signed-off-by: H. Peter Anvin --- kernel/smp.c | 40 ++++++++++++++++++++++++++++++++++------ 1 file changed, 34 insertions(+), 6 deletions(-) (limited to 'kernel') diff --git a/kernel/smp.c b/kernel/smp.c index ad63d8501207..2accdf6712e5 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -176,6 +176,11 @@ void generic_smp_call_function_interrupt(void) struct call_function_data *data; int cpu = get_cpu(); + /* + * Shouldn't receive this interrupt on a cpu that is not yet online. + */ + WARN_ON_ONCE(!cpu_online(cpu)); + /* * Ensure entry is visible on call_function_queue after we have * entered the IPI. See comment in smp_call_function_many. @@ -230,6 +235,11 @@ void generic_smp_call_function_single_interrupt(void) unsigned int data_flags; LIST_HEAD(list); + /* + * Shouldn't receive this interrupt on a cpu that is not yet online. + */ + WARN_ON_ONCE(!cpu_online(smp_processor_id())); + spin_lock(&q->lock); list_replace_init(&q->list, &list); spin_unlock(&q->lock); @@ -285,8 +295,14 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, */ this_cpu = get_cpu(); - /* Can deadlock when called with interrupts disabled */ - WARN_ON_ONCE(irqs_disabled() && !oops_in_progress); + /* + * Can deadlock when called with interrupts disabled. + * We allow cpu's that are not yet online though, as no one else can + * send smp call function interrupt to this cpu and as such deadlocks + * can't happen. + */ + WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled() + && !oops_in_progress); if (cpu == this_cpu) { local_irq_save(flags); @@ -329,8 +345,14 @@ void __smp_call_function_single(int cpu, struct call_single_data *data, { csd_lock(data); - /* Can deadlock when called with interrupts disabled */ - WARN_ON_ONCE(wait && irqs_disabled() && !oops_in_progress); + /* + * Can deadlock when called with interrupts disabled. + * We allow cpu's that are not yet online though, as no one else can + * send smp call function interrupt to this cpu and as such deadlocks + * can't happen. + */ + WARN_ON_ONCE(cpu_online(smp_processor_id()) && wait && irqs_disabled() + && !oops_in_progress); generic_exec_single(cpu, data, wait); } @@ -365,8 +387,14 @@ void smp_call_function_many(const struct cpumask *mask, unsigned long flags; int cpu, next_cpu, this_cpu = smp_processor_id(); - /* Can deadlock when called with interrupts disabled */ - WARN_ON_ONCE(irqs_disabled() && !oops_in_progress); + /* + * Can deadlock when called with interrupts disabled. + * We allow cpu's that are not yet online though, as no one else can + * send smp call function interrupt to this cpu and as such deadlocks + * can't happen. + */ + WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled() + && !oops_in_progress); /* So, what's a CPU they want? Ignoring this one. */ cpu = cpumask_first_and(mask, cpu_online_mask); -- cgit v1.2.3 From d0af9eed5aa91b6b7b5049cae69e5ea956fd85c3 Mon Sep 17 00:00:00 2001 From: Suresh Siddha Date: Wed, 19 Aug 2009 18:05:36 -0700 Subject: x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init SDM Vol 3a section titled "MTRR considerations in MP systems" specifies the need for synchronizing the logical cpu's while initializing/updating MTRR. Currently Linux kernel does the synchronization of all cpu's only when a single MTRR register is programmed/updated. During an AP online (during boot/cpu-online/resume) where we initialize all the MTRR/PAT registers, we don't follow this synchronization algorithm. This can lead to scenarios where during a dynamic cpu online, that logical cpu is initializing MTRR/PAT with cache disabled (cr0.cd=1) etc while other logical HT sibling continue to run (also with cache disabled because of cr0.cd=1 on its sibling). Starting from Westmere, VMX transitions with cr0.cd=1 don't work properly (because of some VMX performance optimizations) and the above scenario (with one logical cpu doing VMX activity and another logical cpu coming online) can result in system crash. Fix the MTRR initialization by doing rendezvous of all the cpus. During boot and resume, we delay the MTRR/PAT init for APs till all the logical cpu's come online and the rendezvous process at the end of AP's bringup, will initialize the MTRR/PAT for all AP's. For dynamic single cpu online, we synchronize all the logical cpus and do the MTRR/PAT init on the AP that is coming online. Signed-off-by: Suresh Siddha Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/mtrr.h | 7 +++++++ arch/x86/kernel/cpu/mtrr/main.c | 46 +++++++++++++++++++++++++++++++++-------- arch/x86/kernel/smpboot.c | 14 +++++++++++++ arch/x86/power/cpu.c | 2 +- kernel/cpu.c | 14 +++++++++++++ 5 files changed, 73 insertions(+), 10 deletions(-) (limited to 'kernel') diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h index a51ada8467de..d5366ec5cb8f 100644 --- a/arch/x86/include/asm/mtrr.h +++ b/arch/x86/include/asm/mtrr.h @@ -121,8 +121,12 @@ extern int mtrr_del_page(int reg, unsigned long base, unsigned long size); extern void mtrr_centaur_report_mcr(int mcr, u32 lo, u32 hi); extern void mtrr_ap_init(void); extern void mtrr_bp_init(void); +extern void set_mtrr_aps_delayed_init(void); +extern void mtrr_aps_init(void); +extern void mtrr_bp_restore(void); extern int mtrr_trim_uncached_memory(unsigned long end_pfn); extern int amd_special_default_mtrr(void); +extern u32 mtrr_aps_delayed_init; # else static inline u8 mtrr_type_lookup(u64 addr, u64 end) { @@ -161,6 +165,9 @@ static inline void mtrr_centaur_report_mcr(int mcr, u32 lo, u32 hi) #define mtrr_ap_init() do {} while (0) #define mtrr_bp_init() do {} while (0) +#define set_mtrr_aps_delayed_init() do {} while (0) +#define mtrr_aps_init() do {} while (0) +#define mtrr_bp_restore() do {} while (0) # endif #ifdef CONFIG_COMPAT diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index 7af0f88a4163..7339be0aa580 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -58,6 +58,7 @@ unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES]; static DEFINE_MUTEX(mtrr_mutex); u64 size_or_mask, size_and_mask; +u32 mtrr_aps_delayed_init; static struct mtrr_ops *mtrr_ops[X86_VENDOR_NUM]; @@ -163,7 +164,10 @@ static void ipi_handler(void *info) if (data->smp_reg != ~0U) { mtrr_if->set(data->smp_reg, data->smp_base, data->smp_size, data->smp_type); - } else { + } else if (mtrr_aps_delayed_init) { + /* + * Initialize the MTRRs inaddition to the synchronisation. + */ mtrr_if->set_all(); } @@ -265,6 +269,8 @@ set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type typ */ if (reg != ~0U) mtrr_if->set(reg, base, size, type); + else if (!mtrr_aps_delayed_init) + mtrr_if->set_all(); /* Wait for the others */ while (atomic_read(&data.count)) @@ -721,9 +727,7 @@ void __init mtrr_bp_init(void) void mtrr_ap_init(void) { - unsigned long flags; - - if (!mtrr_if || !use_intel()) + if (!use_intel() || mtrr_aps_delayed_init) return; /* * Ideally we should hold mtrr_mutex here to avoid mtrr entries @@ -738,11 +742,7 @@ void mtrr_ap_init(void) * 2. cpu hotadd time. We let mtrr_add/del_page hold cpuhotplug * lock to prevent mtrr entry changes */ - local_irq_save(flags); - - mtrr_if->set_all(); - - local_irq_restore(flags); + set_mtrr(~0U, 0, 0, 0); } /** @@ -753,6 +753,34 @@ void mtrr_save_state(void) smp_call_function_single(0, mtrr_save_fixed_ranges, NULL, 1); } +void set_mtrr_aps_delayed_init(void) +{ + if (!use_intel()) + return; + + mtrr_aps_delayed_init = 1; +} + +/* + * MTRR initialization for all AP's + */ +void mtrr_aps_init(void) +{ + if (!use_intel()) + return; + + set_mtrr(~0U, 0, 0, 0); + mtrr_aps_delayed_init = 0; +} + +void mtrr_bp_restore(void) +{ + if (!use_intel()) + return; + + mtrr_if->set_all(); +} + static int __init mtrr_init_finialize(void) { if (!mtrr_if) diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 2fecda69ee64..d720b7e0cf3d 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1116,9 +1116,22 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) if (is_uv_system()) uv_system_init(); + + set_mtrr_aps_delayed_init(); out: preempt_enable(); } + +void arch_enable_nonboot_cpus_begin(void) +{ + set_mtrr_aps_delayed_init(); +} + +void arch_enable_nonboot_cpus_end(void) +{ + mtrr_aps_init(); +} + /* * Early setup to make printk work. */ @@ -1140,6 +1153,7 @@ void __init native_smp_cpus_done(unsigned int max_cpus) setup_ioapic_dest(); #endif check_nmi_watchdog(); + mtrr_aps_init(); } static int __initdata setup_possible_cpus = -1; diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c index b3d20b9cac63..417c9f5b4afa 100644 --- a/arch/x86/power/cpu.c +++ b/arch/x86/power/cpu.c @@ -242,7 +242,7 @@ static void __restore_processor_state(struct saved_context *ctxt) fix_processor_context(); do_fpu_end(); - mtrr_ap_init(); + mtrr_bp_restore(); #ifdef CONFIG_X86_OLD_MCE mcheck_init(&boot_cpu_data); diff --git a/kernel/cpu.c b/kernel/cpu.c index 8ce10043e4ac..f5f9485b8c0f 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -413,6 +413,14 @@ int disable_nonboot_cpus(void) return error; } +void __weak arch_enable_nonboot_cpus_begin(void) +{ +} + +void __weak arch_enable_nonboot_cpus_end(void) +{ +} + void __ref enable_nonboot_cpus(void) { int cpu, error; @@ -424,6 +432,9 @@ void __ref enable_nonboot_cpus(void) goto out; printk("Enabling non-boot CPUs ...\n"); + + arch_enable_nonboot_cpus_begin(); + for_each_cpu(cpu, frozen_cpus) { error = _cpu_up(cpu, 1); if (!error) { @@ -432,6 +443,9 @@ void __ref enable_nonboot_cpus(void) } printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error); } + + arch_enable_nonboot_cpus_end(); + cpumask_clear(frozen_cpus); out: cpu_maps_update_done(); -- cgit v1.2.3 From 5e928f77a09a07f9dd595bb8a489965d69a83458 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 18 Aug 2009 23:38:32 +0200 Subject: PM: Introduce core framework for run-time PM of I/O devices (rev. 17) Introduce a core framework for run-time power management of I/O devices. Add device run-time PM fields to 'struct dev_pm_info' and device run-time PM callbacks to 'struct dev_pm_ops'. Introduce a run-time PM workqueue and define some device run-time PM helper functions at the core level. Document all these things. Special thanks to Alan Stern for his help with the design and multiple detailed reviews of the pereceding versions of this patch and to Magnus Damm for testing feedback. Signed-off-by: Rafael J. Wysocki Acked-by: Magnus Damm --- Documentation/power/runtime_pm.txt | 378 ++++++++++++++ drivers/base/dd.c | 11 + drivers/base/power/Makefile | 1 + drivers/base/power/main.c | 22 +- drivers/base/power/power.h | 31 +- drivers/base/power/runtime.c | 1011 ++++++++++++++++++++++++++++++++++++ include/linux/pm.h | 101 +++- include/linux/pm_runtime.h | 114 ++++ kernel/power/Kconfig | 14 + kernel/power/main.c | 17 + 10 files changed, 1689 insertions(+), 11 deletions(-) create mode 100644 Documentation/power/runtime_pm.txt create mode 100644 drivers/base/power/runtime.c create mode 100644 include/linux/pm_runtime.h (limited to 'kernel') diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt new file mode 100644 index 000000000000..f49a33b704d2 --- /dev/null +++ b/Documentation/power/runtime_pm.txt @@ -0,0 +1,378 @@ +Run-time Power Management Framework for I/O Devices + +(C) 2009 Rafael J. Wysocki , Novell Inc. + +1. Introduction + +Support for run-time power management (run-time PM) of I/O devices is provided +at the power management core (PM core) level by means of: + +* The power management workqueue pm_wq in which bus types and device drivers can + put their PM-related work items. It is strongly recommended that pm_wq be + used for queuing all work items related to run-time PM, because this allows + them to be synchronized with system-wide power transitions (suspend to RAM, + hibernation and resume from system sleep states). pm_wq is declared in + include/linux/pm_runtime.h and defined in kernel/power/main.c. + +* A number of run-time PM fields in the 'power' member of 'struct device' (which + is of the type 'struct dev_pm_info', defined in include/linux/pm.h) that can + be used for synchronizing run-time PM operations with one another. + +* Three device run-time PM callbacks in 'struct dev_pm_ops' (defined in + include/linux/pm.h). + +* A set of helper functions defined in drivers/base/power/runtime.c that can be + used for carrying out run-time PM operations in such a way that the + synchronization between them is taken care of by the PM core. Bus types and + device drivers are encouraged to use these functions. + +The run-time PM callbacks present in 'struct dev_pm_ops', the device run-time PM +fields of 'struct dev_pm_info' and the core helper functions provided for +run-time PM are described below. + +2. Device Run-time PM Callbacks + +There are three device run-time PM callbacks defined in 'struct dev_pm_ops': + +struct dev_pm_ops { + ... + int (*runtime_suspend)(struct device *dev); + int (*runtime_resume)(struct device *dev); + void (*runtime_idle)(struct device *dev); + ... +}; + +The ->runtime_suspend() callback is executed by the PM core for the bus type of +the device being suspended. The bus type's callback is then _entirely_ +_responsible_ for handling the device as appropriate, which may, but need not +include executing the device driver's own ->runtime_suspend() callback (from the +PM core's point of view it is not necessary to implement a ->runtime_suspend() +callback in a device driver as long as the bus type's ->runtime_suspend() knows +what to do to handle the device). + + * Once the bus type's ->runtime_suspend() callback has completed successfully + for given device, the PM core regards the device as suspended, which need + not mean that the device has been put into a low power state. It is + supposed to mean, however, that the device will not process data and will + not communicate with the CPU(s) and RAM until its bus type's + ->runtime_resume() callback is executed for it. The run-time PM status of + a device after successful execution of its bus type's ->runtime_suspend() + callback is 'suspended'. + + * If the bus type's ->runtime_suspend() callback returns -EBUSY or -EAGAIN, + the device's run-time PM status is supposed to be 'active', which means that + the device _must_ be fully operational afterwards. + + * If the bus type's ->runtime_suspend() callback returns an error code + different from -EBUSY or -EAGAIN, the PM core regards this as a fatal + error and will refuse to run the helper functions described in Section 4 + for the device, until the status of it is directly set either to 'active' + or to 'suspended' (the PM core provides special helper functions for this + purpose). + +In particular, if the driver requires remote wakeup capability for proper +functioning and device_may_wakeup() returns 'false' for the device, then +->runtime_suspend() should return -EBUSY. On the other hand, if +device_may_wakeup() returns 'true' for the device and the device is put +into a low power state during the execution of its bus type's +->runtime_suspend(), it is expected that remote wake-up (i.e. hardware mechanism +allowing the device to request a change of its power state, such as PCI PME) +will be enabled for the device. Generally, remote wake-up should be enabled +for all input devices put into a low power state at run time. + +The ->runtime_resume() callback is executed by the PM core for the bus type of +the device being woken up. The bus type's callback is then _entirely_ +_responsible_ for handling the device as appropriate, which may, but need not +include executing the device driver's own ->runtime_resume() callback (from the +PM core's point of view it is not necessary to implement a ->runtime_resume() +callback in a device driver as long as the bus type's ->runtime_resume() knows +what to do to handle the device). + + * Once the bus type's ->runtime_resume() callback has completed successfully, + the PM core regards the device as fully operational, which means that the + device _must_ be able to complete I/O operations as needed. The run-time + PM status of the device is then 'active'. + + * If the bus type's ->runtime_resume() callback returns an error code, the PM + core regards this as a fatal error and will refuse to run the helper + functions described in Section 4 for the device, until its status is + directly set either to 'active' or to 'suspended' (the PM core provides + special helper functions for this purpose). + +The ->runtime_idle() callback is executed by the PM core for the bus type of +given device whenever the device appears to be idle, which is indicated to the +PM core by two counters, the device's usage counter and the counter of 'active' +children of the device. + + * If any of these counters is decreased using a helper function provided by + the PM core and it turns out to be equal to zero, the other counter is + checked. If that counter also is equal to zero, the PM core executes the + device bus type's ->runtime_idle() callback (with the device as an + argument). + +The action performed by a bus type's ->runtime_idle() callback is totally +dependent on the bus type in question, but the expected and recommended action +is to check if the device can be suspended (i.e. if all of the conditions +necessary for suspending the device are satisfied) and to queue up a suspend +request for the device in that case. + +The helper functions provided by the PM core, described in Section 4, guarantee +that the following constraints are met with respect to the bus type's run-time +PM callbacks: + +(1) The callbacks are mutually exclusive (e.g. it is forbidden to execute + ->runtime_suspend() in parallel with ->runtime_resume() or with another + instance of ->runtime_suspend() for the same device) with the exception that + ->runtime_suspend() or ->runtime_resume() can be executed in parallel with + ->runtime_idle() (although ->runtime_idle() will not be started while any + of the other callbacks is being executed for the same device). + +(2) ->runtime_idle() and ->runtime_suspend() can only be executed for 'active' + devices (i.e. the PM core will only execute ->runtime_idle() or + ->runtime_suspend() for the devices the run-time PM status of which is + 'active'). + +(3) ->runtime_idle() and ->runtime_suspend() can only be executed for a device + the usage counter of which is equal to zero _and_ either the counter of + 'active' children of which is equal to zero, or the 'power.ignore_children' + flag of which is set. + +(4) ->runtime_resume() can only be executed for 'suspended' devices (i.e. the + PM core will only execute ->runtime_resume() for the devices the run-time + PM status of which is 'suspended'). + +Additionally, the helper functions provided by the PM core obey the following +rules: + + * If ->runtime_suspend() is about to be executed or there's a pending request + to execute it, ->runtime_idle() will not be executed for the same device. + + * A request to execute or to schedule the execution of ->runtime_suspend() + will cancel any pending requests to execute ->runtime_idle() for the same + device. + + * If ->runtime_resume() is about to be executed or there's a pending request + to execute it, the other callbacks will not be executed for the same device. + + * A request to execute ->runtime_resume() will cancel any pending or + scheduled requests to execute the other callbacks for the same device. + +3. Run-time PM Device Fields + +The following device run-time PM fields are present in 'struct dev_pm_info', as +defined in include/linux/pm.h: + + struct timer_list suspend_timer; + - timer used for scheduling (delayed) suspend request + + unsigned long timer_expires; + - timer expiration time, in jiffies (if this is different from zero, the + timer is running and will expire at that time, otherwise the timer is not + running) + + struct work_struct work; + - work structure used for queuing up requests (i.e. work items in pm_wq) + + wait_queue_head_t wait_queue; + - wait queue used if any of the helper functions needs to wait for another + one to complete + + spinlock_t lock; + - lock used for synchronisation + + atomic_t usage_count; + - the usage counter of the device + + atomic_t child_count; + - the count of 'active' children of the device + + unsigned int ignore_children; + - if set, the value of child_count is ignored (but still updated) + + unsigned int disable_depth; + - used for disabling the helper funcions (they work normally if this is + equal to zero); the initial value of it is 1 (i.e. run-time PM is + initially disabled for all devices) + + unsigned int runtime_error; + - if set, there was a fatal error (one of the callbacks returned error code + as described in Section 2), so the helper funtions will not work until + this flag is cleared; this is the error code returned by the failing + callback + + unsigned int idle_notification; + - if set, ->runtime_idle() is being executed + + unsigned int request_pending; + - if set, there's a pending request (i.e. a work item queued up into pm_wq) + + enum rpm_request request; + - type of request that's pending (valid if request_pending is set) + + unsigned int deferred_resume; + - set if ->runtime_resume() is about to be run while ->runtime_suspend() is + being executed for that device and it is not practical to wait for the + suspend to complete; means "start a resume as soon as you've suspended" + + enum rpm_status runtime_status; + - the run-time PM status of the device; this field's initial value is + RPM_SUSPENDED, which means that each device is initially regarded by the + PM core as 'suspended', regardless of its real hardware status + +All of the above fields are members of the 'power' member of 'struct device'. + +4. Run-time PM Device Helper Functions + +The following run-time PM helper functions are defined in +drivers/base/power/runtime.c and include/linux/pm_runtime.h: + + void pm_runtime_init(struct device *dev); + - initialize the device run-time PM fields in 'struct dev_pm_info' + + void pm_runtime_remove(struct device *dev); + - make sure that the run-time PM of the device will be disabled after + removing the device from device hierarchy + + int pm_runtime_idle(struct device *dev); + - execute ->runtime_idle() for the device's bus type; returns 0 on success + or error code on failure, where -EINPROGRESS means that ->runtime_idle() + is already being executed + + int pm_runtime_suspend(struct device *dev); + - execute ->runtime_suspend() for the device's bus type; returns 0 on + success, 1 if the device's run-time PM status was already 'suspended', or + error code on failure, where -EAGAIN or -EBUSY means it is safe to attempt + to suspend the device again in future + + int pm_runtime_resume(struct device *dev); + - execute ->runtime_resume() for the device's bus type; returns 0 on + success, 1 if the device's run-time PM status was already 'active' or + error code on failure, where -EAGAIN means it may be safe to attempt to + resume the device again in future, but 'power.runtime_error' should be + checked additionally + + int pm_request_idle(struct device *dev); + - submit a request to execute ->runtime_idle() for the device's bus type + (the request is represented by a work item in pm_wq); returns 0 on success + or error code if the request has not been queued up + + int pm_schedule_suspend(struct device *dev, unsigned int delay); + - schedule the execution of ->runtime_suspend() for the device's bus type + in future, where 'delay' is the time to wait before queuing up a suspend + work item in pm_wq, in milliseconds (if 'delay' is zero, the work item is + queued up immediately); returns 0 on success, 1 if the device's PM + run-time status was already 'suspended', or error code if the request + hasn't been scheduled (or queued up if 'delay' is 0); if the execution of + ->runtime_suspend() is already scheduled and not yet expired, the new + value of 'delay' will be used as the time to wait + + int pm_request_resume(struct device *dev); + - submit a request to execute ->runtime_resume() for the device's bus type + (the request is represented by a work item in pm_wq); returns 0 on + success, 1 if the device's run-time PM status was already 'active', or + error code if the request hasn't been queued up + + void pm_runtime_get_noresume(struct device *dev); + - increment the device's usage counter + + int pm_runtime_get(struct device *dev); + - increment the device's usage counter, run pm_request_resume(dev) and + return its result + + int pm_runtime_get_sync(struct device *dev); + - increment the device's usage counter, run pm_runtime_resume(dev) and + return its result + + void pm_runtime_put_noidle(struct device *dev); + - decrement the device's usage counter + + int pm_runtime_put(struct device *dev); + - decrement the device's usage counter, run pm_request_idle(dev) and return + its result + + int pm_runtime_put_sync(struct device *dev); + - decrement the device's usage counter, run pm_runtime_idle(dev) and return + its result + + void pm_runtime_enable(struct device *dev); + - enable the run-time PM helper functions to run the device bus type's + run-time PM callbacks described in Section 2 + + int pm_runtime_disable(struct device *dev); + - prevent the run-time PM helper functions from running the device bus + type's run-time PM callbacks, make sure that all of the pending run-time + PM operations on the device are either completed or canceled; returns + 1 if there was a resume request pending and it was necessary to execute + ->runtime_resume() for the device's bus type to satisfy that request, + otherwise 0 is returned + + void pm_suspend_ignore_children(struct device *dev, bool enable); + - set/unset the power.ignore_children flag of the device + + int pm_runtime_set_active(struct device *dev); + - clear the device's 'power.runtime_error' flag, set the device's run-time + PM status to 'active' and update its parent's counter of 'active' + children as appropriate (it is only valid to use this function if + 'power.runtime_error' is set or 'power.disable_depth' is greater than + zero); it will fail and return error code if the device has a parent + which is not active and the 'power.ignore_children' flag of which is unset + + void pm_runtime_set_suspended(struct device *dev); + - clear the device's 'power.runtime_error' flag, set the device's run-time + PM status to 'suspended' and update its parent's counter of 'active' + children as appropriate (it is only valid to use this function if + 'power.runtime_error' is set or 'power.disable_depth' is greater than + zero) + +It is safe to execute the following helper functions from interrupt context: + +pm_request_idle() +pm_schedule_suspend() +pm_request_resume() +pm_runtime_get_noresume() +pm_runtime_get() +pm_runtime_put_noidle() +pm_runtime_put() +pm_suspend_ignore_children() +pm_runtime_set_active() +pm_runtime_set_suspended() +pm_runtime_enable() + +5. Run-time PM Initialization, Device Probing and Removal + +Initially, the run-time PM is disabled for all devices, which means that the +majority of the run-time PM helper funtions described in Section 4 will return +-EAGAIN until pm_runtime_enable() is called for the device. + +In addition to that, the initial run-time PM status of all devices is +'suspended', but it need not reflect the actual physical state of the device. +Thus, if the device is initially active (i.e. it is able to process I/O), its +run-time PM status must be changed to 'active', with the help of +pm_runtime_set_active(), before pm_runtime_enable() is called for the device. + +However, if the device has a parent and the parent's run-time PM is enabled, +calling pm_runtime_set_active() for the device will affect the parent, unless +the parent's 'power.ignore_children' flag is set. Namely, in that case the +parent won't be able to suspend at run time, using the PM core's helper +functions, as long as the child's status is 'active', even if the child's +run-time PM is still disabled (i.e. pm_runtime_enable() hasn't been called for +the child yet or pm_runtime_disable() has been called for it). For this reason, +once pm_runtime_set_active() has been called for the device, pm_runtime_enable() +should be called for it too as soon as reasonably possible or its run-time PM +status should be changed back to 'suspended' with the help of +pm_runtime_set_suspended(). + +If the default initial run-time PM status of the device (i.e. 'suspended') +reflects the actual state of the device, its bus type's or its driver's +->probe() callback will likely need to wake it up using one of the PM core's +helper functions described in Section 4. In that case, pm_runtime_resume() +should be used. Of course, for this purpose the device's run-time PM has to be +enabled earlier by calling pm_runtime_enable(). + +If the device bus type's or driver's ->probe() or ->remove() callback runs +pm_runtime_suspend() or pm_runtime_idle() or their asynchronous counterparts, +they will fail returning -EAGAIN, because the device's usage counter is +incremented by the core before executing ->probe() and ->remove(). Still, it +may be desirable to suspend the device as soon as ->probe() or ->remove() has +finished, so the PM core uses pm_runtime_idle_sync() to invoke the device bus +type's ->runtime_idle() callback at that time. diff --git a/drivers/base/dd.c b/drivers/base/dd.c index f0106875f01d..7b34b3a48f67 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -23,6 +23,7 @@ #include #include #include +#include #include "base.h" #include "power/power.h" @@ -202,7 +203,10 @@ int driver_probe_device(struct device_driver *drv, struct device *dev) pr_debug("bus: '%s': %s: matched device %s with driver %s\n", drv->bus->name, __func__, dev_name(dev), drv->name); + pm_runtime_get_noresume(dev); + pm_runtime_barrier(dev); ret = really_probe(dev, drv); + pm_runtime_put_sync(dev); return ret; } @@ -245,7 +249,9 @@ int device_attach(struct device *dev) ret = 0; } } else { + pm_runtime_get_noresume(dev); ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach); + pm_runtime_put_sync(dev); } up(&dev->sem); return ret; @@ -306,6 +312,9 @@ static void __device_release_driver(struct device *dev) drv = dev->driver; if (drv) { + pm_runtime_get_noresume(dev); + pm_runtime_barrier(dev); + driver_sysfs_remove(dev); if (dev->bus) @@ -324,6 +333,8 @@ static void __device_release_driver(struct device *dev) blocking_notifier_call_chain(&dev->bus->p->bus_notifier, BUS_NOTIFY_UNBOUND_DRIVER, dev); + + pm_runtime_put_sync(dev); } } diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile index 911208b89259..3ce3519e8f30 100644 --- a/drivers/base/power/Makefile +++ b/drivers/base/power/Makefile @@ -1,5 +1,6 @@ obj-$(CONFIG_PM) += sysfs.o obj-$(CONFIG_PM_SLEEP) += main.o +obj-$(CONFIG_PM_RUNTIME) += runtime.o obj-$(CONFIG_PM_TRACE_RTC) += trace.o ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 1b1a786b7dec..86990011277b 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -48,6 +49,16 @@ static DEFINE_MUTEX(dpm_list_mtx); */ static bool transition_started; +/** + * device_pm_init - Initialize the PM-related part of a device object + * @dev: Device object being initialized. + */ +void device_pm_init(struct device *dev) +{ + dev->power.status = DPM_ON; + pm_runtime_init(dev); +} + /** * device_pm_lock - lock the list of active devices used by the PM core */ @@ -105,6 +116,7 @@ void device_pm_remove(struct device *dev) mutex_lock(&dpm_list_mtx); list_del_init(&dev->power.entry); mutex_unlock(&dpm_list_mtx); + pm_runtime_remove(dev); } /** @@ -512,6 +524,7 @@ static void dpm_complete(pm_message_t state) mutex_unlock(&dpm_list_mtx); device_complete(dev, state); + pm_runtime_put_noidle(dev); mutex_lock(&dpm_list_mtx); } @@ -757,7 +770,14 @@ static int dpm_prepare(pm_message_t state) dev->power.status = DPM_PREPARING; mutex_unlock(&dpm_list_mtx); - error = device_prepare(dev, state); + pm_runtime_get_noresume(dev); + if (pm_runtime_barrier(dev) && device_may_wakeup(dev)) { + /* Wake-up requested during system sleep transition. */ + pm_runtime_put_noidle(dev); + error = -EBUSY; + } else { + error = device_prepare(dev, state); + } mutex_lock(&dpm_list_mtx); if (error) { diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h index c7cb4fc3735c..b8fa1aa5225a 100644 --- a/drivers/base/power/power.h +++ b/drivers/base/power/power.h @@ -1,7 +1,14 @@ -static inline void device_pm_init(struct device *dev) -{ - dev->power.status = DPM_ON; -} +#ifdef CONFIG_PM_RUNTIME + +extern void pm_runtime_init(struct device *dev); +extern void pm_runtime_remove(struct device *dev); + +#else /* !CONFIG_PM_RUNTIME */ + +static inline void pm_runtime_init(struct device *dev) {} +static inline void pm_runtime_remove(struct device *dev) {} + +#endif /* !CONFIG_PM_RUNTIME */ #ifdef CONFIG_PM_SLEEP @@ -16,23 +23,33 @@ static inline struct device *to_device(struct list_head *entry) return container_of(entry, struct device, power.entry); } +extern void device_pm_init(struct device *dev); extern void device_pm_add(struct device *); extern void device_pm_remove(struct device *); extern void device_pm_move_before(struct device *, struct device *); extern void device_pm_move_after(struct device *, struct device *); extern void device_pm_move_last(struct device *); -#else /* CONFIG_PM_SLEEP */ +#else /* !CONFIG_PM_SLEEP */ + +static inline void device_pm_init(struct device *dev) +{ + pm_runtime_init(dev); +} + +static inline void device_pm_remove(struct device *dev) +{ + pm_runtime_remove(dev); +} static inline void device_pm_add(struct device *dev) {} -static inline void device_pm_remove(struct device *dev) {} static inline void device_pm_move_before(struct device *deva, struct device *devb) {} static inline void device_pm_move_after(struct device *deva, struct device *devb) {} static inline void device_pm_move_last(struct device *dev) {} -#endif +#endif /* !CONFIG_PM_SLEEP */ #ifdef CONFIG_PM diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c new file mode 100644 index 000000000000..38556f6cc22d --- /dev/null +++ b/drivers/base/power/runtime.c @@ -0,0 +1,1011 @@ +/* + * drivers/base/power/runtime.c - Helper functions for device run-time PM + * + * Copyright (c) 2009 Rafael J. Wysocki , Novell Inc. + * + * This file is released under the GPLv2. + */ + +#include +#include +#include + +static int __pm_runtime_resume(struct device *dev, bool from_wq); +static int __pm_request_idle(struct device *dev); +static int __pm_request_resume(struct device *dev); + +/** + * pm_runtime_deactivate_timer - Deactivate given device's suspend timer. + * @dev: Device to handle. + */ +static void pm_runtime_deactivate_timer(struct device *dev) +{ + if (dev->power.timer_expires > 0) { + del_timer(&dev->power.suspend_timer); + dev->power.timer_expires = 0; + } +} + +/** + * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests. + * @dev: Device to handle. + */ +static void pm_runtime_cancel_pending(struct device *dev) +{ + pm_runtime_deactivate_timer(dev); + /* + * In case there's a request pending, make sure its work function will + * return without doing anything. + */ + dev->power.request = RPM_REQ_NONE; +} + +/** + * __pm_runtime_idle - Notify device bus type if the device can be suspended. + * @dev: Device to notify the bus type about. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int __pm_runtime_idle(struct device *dev) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + int retval = 0; + + dev_dbg(dev, "__pm_runtime_idle()!\n"); + + if (dev->power.runtime_error) + retval = -EINVAL; + else if (dev->power.idle_notification) + retval = -EINPROGRESS; + else if (atomic_read(&dev->power.usage_count) > 0 + || dev->power.disable_depth > 0 + || dev->power.runtime_status != RPM_ACTIVE) + retval = -EAGAIN; + else if (!pm_children_suspended(dev)) + retval = -EBUSY; + if (retval) + goto out; + + if (dev->power.request_pending) { + /* + * If an idle notification request is pending, cancel it. Any + * other pending request takes precedence over us. + */ + if (dev->power.request == RPM_REQ_IDLE) { + dev->power.request = RPM_REQ_NONE; + } else if (dev->power.request != RPM_REQ_NONE) { + retval = -EAGAIN; + goto out; + } + } + + dev->power.idle_notification = true; + + if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_idle) { + spin_unlock_irq(&dev->power.lock); + + dev->bus->pm->runtime_idle(dev); + + spin_lock_irq(&dev->power.lock); + } + + dev->power.idle_notification = false; + wake_up_all(&dev->power.wait_queue); + + out: + dev_dbg(dev, "__pm_runtime_idle() returns %d!\n", retval); + + return retval; +} + +/** + * pm_runtime_idle - Notify device bus type if the device can be suspended. + * @dev: Device to notify the bus type about. + */ +int pm_runtime_idle(struct device *dev) +{ + int retval; + + spin_lock_irq(&dev->power.lock); + retval = __pm_runtime_idle(dev); + spin_unlock_irq(&dev->power.lock); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_runtime_idle); + +/** + * __pm_runtime_suspend - Carry out run-time suspend of given device. + * @dev: Device to suspend. + * @from_wq: If set, the function has been called via pm_wq. + * + * Check if the device can be suspended and run the ->runtime_suspend() callback + * provided by its bus type. If another suspend has been started earlier, wait + * for it to finish. If an idle notification or suspend request is pending or + * scheduled, cancel it. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +int __pm_runtime_suspend(struct device *dev, bool from_wq) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + struct device *parent = NULL; + bool notify = false; + int retval = 0; + + dev_dbg(dev, "__pm_runtime_suspend()%s!\n", + from_wq ? " from workqueue" : ""); + + repeat: + if (dev->power.runtime_error) { + retval = -EINVAL; + goto out; + } + + /* Pending resume requests take precedence over us. */ + if (dev->power.request_pending + && dev->power.request == RPM_REQ_RESUME) { + retval = -EAGAIN; + goto out; + } + + /* Other scheduled or pending requests need to be canceled. */ + pm_runtime_cancel_pending(dev); + + if (dev->power.runtime_status == RPM_SUSPENDED) + retval = 1; + else if (dev->power.runtime_status == RPM_RESUMING + || dev->power.disable_depth > 0 + || atomic_read(&dev->power.usage_count) > 0) + retval = -EAGAIN; + else if (!pm_children_suspended(dev)) + retval = -EBUSY; + if (retval) + goto out; + + if (dev->power.runtime_status == RPM_SUSPENDING) { + DEFINE_WAIT(wait); + + if (from_wq) { + retval = -EINPROGRESS; + goto out; + } + + /* Wait for the other suspend running in parallel with us. */ + for (;;) { + prepare_to_wait(&dev->power.wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (dev->power.runtime_status != RPM_SUSPENDING) + break; + + spin_unlock_irq(&dev->power.lock); + + schedule(); + + spin_lock_irq(&dev->power.lock); + } + finish_wait(&dev->power.wait_queue, &wait); + goto repeat; + } + + dev->power.runtime_status = RPM_SUSPENDING; + + if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_suspend) { + spin_unlock_irq(&dev->power.lock); + + retval = dev->bus->pm->runtime_suspend(dev); + + spin_lock_irq(&dev->power.lock); + dev->power.runtime_error = retval; + } else { + retval = -ENOSYS; + } + + if (retval) { + dev->power.runtime_status = RPM_ACTIVE; + pm_runtime_cancel_pending(dev); + dev->power.deferred_resume = false; + + if (retval == -EAGAIN || retval == -EBUSY) { + notify = true; + dev->power.runtime_error = 0; + } + } else { + dev->power.runtime_status = RPM_SUSPENDED; + + if (dev->parent) { + parent = dev->parent; + atomic_add_unless(&parent->power.child_count, -1, 0); + } + } + wake_up_all(&dev->power.wait_queue); + + if (dev->power.deferred_resume) { + dev->power.deferred_resume = false; + __pm_runtime_resume(dev, false); + retval = -EAGAIN; + goto out; + } + + if (notify) + __pm_runtime_idle(dev); + + if (parent && !parent->power.ignore_children) { + spin_unlock_irq(&dev->power.lock); + + pm_request_idle(parent); + + spin_lock_irq(&dev->power.lock); + } + + out: + dev_dbg(dev, "__pm_runtime_suspend() returns %d!\n", retval); + + return retval; +} + +/** + * pm_runtime_suspend - Carry out run-time suspend of given device. + * @dev: Device to suspend. + */ +int pm_runtime_suspend(struct device *dev) +{ + int retval; + + spin_lock_irq(&dev->power.lock); + retval = __pm_runtime_suspend(dev, false); + spin_unlock_irq(&dev->power.lock); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_runtime_suspend); + +/** + * __pm_runtime_resume - Carry out run-time resume of given device. + * @dev: Device to resume. + * @from_wq: If set, the function has been called via pm_wq. + * + * Check if the device can be woken up and run the ->runtime_resume() callback + * provided by its bus type. If another resume has been started earlier, wait + * for it to finish. If there's a suspend running in parallel with this + * function, wait for it to finish and resume the device. Cancel any scheduled + * or pending requests. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +int __pm_runtime_resume(struct device *dev, bool from_wq) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + struct device *parent = NULL; + int retval = 0; + + dev_dbg(dev, "__pm_runtime_resume()%s!\n", + from_wq ? " from workqueue" : ""); + + repeat: + if (dev->power.runtime_error) { + retval = -EINVAL; + goto out; + } + + pm_runtime_cancel_pending(dev); + + if (dev->power.runtime_status == RPM_ACTIVE) + retval = 1; + else if (dev->power.disable_depth > 0) + retval = -EAGAIN; + if (retval) + goto out; + + if (dev->power.runtime_status == RPM_RESUMING + || dev->power.runtime_status == RPM_SUSPENDING) { + DEFINE_WAIT(wait); + + if (from_wq) { + if (dev->power.runtime_status == RPM_SUSPENDING) + dev->power.deferred_resume = true; + retval = -EINPROGRESS; + goto out; + } + + /* Wait for the operation carried out in parallel with us. */ + for (;;) { + prepare_to_wait(&dev->power.wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (dev->power.runtime_status != RPM_RESUMING + && dev->power.runtime_status != RPM_SUSPENDING) + break; + + spin_unlock_irq(&dev->power.lock); + + schedule(); + + spin_lock_irq(&dev->power.lock); + } + finish_wait(&dev->power.wait_queue, &wait); + goto repeat; + } + + if (!parent && dev->parent) { + /* + * Increment the parent's resume counter and resume it if + * necessary. + */ + parent = dev->parent; + spin_unlock_irq(&dev->power.lock); + + pm_runtime_get_noresume(parent); + + spin_lock_irq(&parent->power.lock); + /* + * We can resume if the parent's run-time PM is disabled or it + * is set to ignore children. + */ + if (!parent->power.disable_depth + && !parent->power.ignore_children) { + __pm_runtime_resume(parent, false); + if (parent->power.runtime_status != RPM_ACTIVE) + retval = -EBUSY; + } + spin_unlock_irq(&parent->power.lock); + + spin_lock_irq(&dev->power.lock); + if (retval) + goto out; + goto repeat; + } + + dev->power.runtime_status = RPM_RESUMING; + + if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_resume) { + spin_unlock_irq(&dev->power.lock); + + retval = dev->bus->pm->runtime_resume(dev); + + spin_lock_irq(&dev->power.lock); + dev->power.runtime_error = retval; + } else { + retval = -ENOSYS; + } + + if (retval) { + dev->power.runtime_status = RPM_SUSPENDED; + pm_runtime_cancel_pending(dev); + } else { + dev->power.runtime_status = RPM_ACTIVE; + if (parent) + atomic_inc(&parent->power.child_count); + } + wake_up_all(&dev->power.wait_queue); + + if (!retval) + __pm_request_idle(dev); + + out: + if (parent) { + spin_unlock_irq(&dev->power.lock); + + pm_runtime_put(parent); + + spin_lock_irq(&dev->power.lock); + } + + dev_dbg(dev, "__pm_runtime_resume() returns %d!\n", retval); + + return retval; +} + +/** + * pm_runtime_resume - Carry out run-time resume of given device. + * @dev: Device to suspend. + */ +int pm_runtime_resume(struct device *dev) +{ + int retval; + + spin_lock_irq(&dev->power.lock); + retval = __pm_runtime_resume(dev, false); + spin_unlock_irq(&dev->power.lock); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_runtime_resume); + +/** + * pm_runtime_work - Universal run-time PM work function. + * @work: Work structure used for scheduling the execution of this function. + * + * Use @work to get the device object the work is to be done for, determine what + * is to be done and execute the appropriate run-time PM function. + */ +static void pm_runtime_work(struct work_struct *work) +{ + struct device *dev = container_of(work, struct device, power.work); + enum rpm_request req; + + spin_lock_irq(&dev->power.lock); + + if (!dev->power.request_pending) + goto out; + + req = dev->power.request; + dev->power.request = RPM_REQ_NONE; + dev->power.request_pending = false; + + switch (req) { + case RPM_REQ_NONE: + break; + case RPM_REQ_IDLE: + __pm_runtime_idle(dev); + break; + case RPM_REQ_SUSPEND: + __pm_runtime_suspend(dev, true); + break; + case RPM_REQ_RESUME: + __pm_runtime_resume(dev, true); + break; + } + + out: + spin_unlock_irq(&dev->power.lock); +} + +/** + * __pm_request_idle - Submit an idle notification request for given device. + * @dev: Device to handle. + * + * Check if the device's run-time PM status is correct for suspending the device + * and queue up a request to run __pm_runtime_idle() for it. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int __pm_request_idle(struct device *dev) +{ + int retval = 0; + + if (dev->power.runtime_error) + retval = -EINVAL; + else if (atomic_read(&dev->power.usage_count) > 0 + || dev->power.disable_depth > 0 + || dev->power.runtime_status == RPM_SUSPENDED + || dev->power.runtime_status == RPM_SUSPENDING) + retval = -EAGAIN; + else if (!pm_children_suspended(dev)) + retval = -EBUSY; + if (retval) + return retval; + + if (dev->power.request_pending) { + /* Any requests other then RPM_REQ_IDLE take precedence. */ + if (dev->power.request == RPM_REQ_NONE) + dev->power.request = RPM_REQ_IDLE; + else if (dev->power.request != RPM_REQ_IDLE) + retval = -EAGAIN; + return retval; + } + + dev->power.request = RPM_REQ_IDLE; + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + + return retval; +} + +/** + * pm_request_idle - Submit an idle notification request for given device. + * @dev: Device to handle. + */ +int pm_request_idle(struct device *dev) +{ + unsigned long flags; + int retval; + + spin_lock_irqsave(&dev->power.lock, flags); + retval = __pm_request_idle(dev); + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_request_idle); + +/** + * __pm_request_suspend - Submit a suspend request for given device. + * @dev: Device to suspend. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int __pm_request_suspend(struct device *dev) +{ + int retval = 0; + + if (dev->power.runtime_error) + return -EINVAL; + + if (dev->power.runtime_status == RPM_SUSPENDED) + retval = 1; + else if (atomic_read(&dev->power.usage_count) > 0 + || dev->power.disable_depth > 0) + retval = -EAGAIN; + else if (dev->power.runtime_status == RPM_SUSPENDING) + retval = -EINPROGRESS; + else if (!pm_children_suspended(dev)) + retval = -EBUSY; + if (retval < 0) + return retval; + + pm_runtime_deactivate_timer(dev); + + if (dev->power.request_pending) { + /* + * Pending resume requests take precedence over us, but we can + * overtake any other pending request. + */ + if (dev->power.request == RPM_REQ_RESUME) + retval = -EAGAIN; + else if (dev->power.request != RPM_REQ_SUSPEND) + dev->power.request = retval ? + RPM_REQ_NONE : RPM_REQ_SUSPEND; + return retval; + } else if (retval) { + return retval; + } + + dev->power.request = RPM_REQ_SUSPEND; + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + + return 0; +} + +/** + * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). + * @data: Device pointer passed by pm_schedule_suspend(). + * + * Check if the time is right and execute __pm_request_suspend() in that case. + */ +static void pm_suspend_timer_fn(unsigned long data) +{ + struct device *dev = (struct device *)data; + unsigned long flags; + unsigned long expires; + + spin_lock_irqsave(&dev->power.lock, flags); + + expires = dev->power.timer_expires; + /* If 'expire' is after 'jiffies' we've been called too early. */ + if (expires > 0 && !time_after(expires, jiffies)) { + dev->power.timer_expires = 0; + __pm_request_suspend(dev); + } + + spin_unlock_irqrestore(&dev->power.lock, flags); +} + +/** + * pm_schedule_suspend - Set up a timer to submit a suspend request in future. + * @dev: Device to suspend. + * @delay: Time to wait before submitting a suspend request, in milliseconds. + */ +int pm_schedule_suspend(struct device *dev, unsigned int delay) +{ + unsigned long flags; + int retval = 0; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (dev->power.runtime_error) { + retval = -EINVAL; + goto out; + } + + if (!delay) { + retval = __pm_request_suspend(dev); + goto out; + } + + pm_runtime_deactivate_timer(dev); + + if (dev->power.request_pending) { + /* + * Pending resume requests take precedence over us, but any + * other pending requests have to be canceled. + */ + if (dev->power.request == RPM_REQ_RESUME) { + retval = -EAGAIN; + goto out; + } + dev->power.request = RPM_REQ_NONE; + } + + if (dev->power.runtime_status == RPM_SUSPENDED) + retval = 1; + else if (dev->power.runtime_status == RPM_SUSPENDING) + retval = -EINPROGRESS; + else if (atomic_read(&dev->power.usage_count) > 0 + || dev->power.disable_depth > 0) + retval = -EAGAIN; + else if (!pm_children_suspended(dev)) + retval = -EBUSY; + if (retval) + goto out; + + dev->power.timer_expires = jiffies + msecs_to_jiffies(delay); + mod_timer(&dev->power.suspend_timer, dev->power.timer_expires); + + out: + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_schedule_suspend); + +/** + * pm_request_resume - Submit a resume request for given device. + * @dev: Device to resume. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int __pm_request_resume(struct device *dev) +{ + int retval = 0; + + if (dev->power.runtime_error) + return -EINVAL; + + if (dev->power.runtime_status == RPM_ACTIVE) + retval = 1; + else if (dev->power.runtime_status == RPM_RESUMING) + retval = -EINPROGRESS; + else if (dev->power.disable_depth > 0) + retval = -EAGAIN; + if (retval < 0) + return retval; + + pm_runtime_deactivate_timer(dev); + + if (dev->power.request_pending) { + /* If non-resume request is pending, we can overtake it. */ + dev->power.request = retval ? RPM_REQ_NONE : RPM_REQ_RESUME; + return retval; + } else if (retval) { + return retval; + } + + dev->power.request = RPM_REQ_RESUME; + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + + return retval; +} + +/** + * pm_request_resume - Submit a resume request for given device. + * @dev: Device to resume. + */ +int pm_request_resume(struct device *dev) +{ + unsigned long flags; + int retval; + + spin_lock_irqsave(&dev->power.lock, flags); + retval = __pm_request_resume(dev); + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_request_resume); + +/** + * __pm_runtime_get - Reference count a device and wake it up, if necessary. + * @dev: Device to handle. + * @sync: If set and the device is suspended, resume it synchronously. + * + * Increment the usage count of the device and if it was zero previously, + * resume it or submit a resume request for it, depending on the value of @sync. + */ +int __pm_runtime_get(struct device *dev, bool sync) +{ + int retval = 1; + + if (atomic_add_return(1, &dev->power.usage_count) == 1) + retval = sync ? pm_runtime_resume(dev) : pm_request_resume(dev); + + return retval; +} +EXPORT_SYMBOL_GPL(__pm_runtime_get); + +/** + * __pm_runtime_put - Decrement the device's usage counter and notify its bus. + * @dev: Device to handle. + * @sync: If the device's bus type is to be notified, do that synchronously. + * + * Decrement the usage count of the device and if it reaches zero, carry out a + * synchronous idle notification or submit an idle notification request for it, + * depending on the value of @sync. + */ +int __pm_runtime_put(struct device *dev, bool sync) +{ + int retval = 0; + + if (atomic_dec_and_test(&dev->power.usage_count)) + retval = sync ? pm_runtime_idle(dev) : pm_request_idle(dev); + + return retval; +} +EXPORT_SYMBOL_GPL(__pm_runtime_put); + +/** + * __pm_runtime_set_status - Set run-time PM status of a device. + * @dev: Device to handle. + * @status: New run-time PM status of the device. + * + * If run-time PM of the device is disabled or its power.runtime_error field is + * different from zero, the status may be changed either to RPM_ACTIVE, or to + * RPM_SUSPENDED, as long as that reflects the actual state of the device. + * However, if the device has a parent and the parent is not active, and the + * parent's power.ignore_children flag is unset, the device's status cannot be + * set to RPM_ACTIVE, so -EBUSY is returned in that case. + * + * If successful, __pm_runtime_set_status() clears the power.runtime_error field + * and the device parent's counter of unsuspended children is modified to + * reflect the new status. If the new status is RPM_SUSPENDED, an idle + * notification request for the parent is submitted. + */ +int __pm_runtime_set_status(struct device *dev, unsigned int status) +{ + struct device *parent = dev->parent; + unsigned long flags; + bool notify_parent = false; + int error = 0; + + if (status != RPM_ACTIVE && status != RPM_SUSPENDED) + return -EINVAL; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (!dev->power.runtime_error && !dev->power.disable_depth) { + error = -EAGAIN; + goto out; + } + + if (dev->power.runtime_status == status) + goto out_set; + + if (status == RPM_SUSPENDED) { + /* It always is possible to set the status to 'suspended'. */ + if (parent) { + atomic_add_unless(&parent->power.child_count, -1, 0); + notify_parent = !parent->power.ignore_children; + } + goto out_set; + } + + if (parent) { + spin_lock_irq(&parent->power.lock); + + /* + * It is invalid to put an active child under a parent that is + * not active, has run-time PM enabled and the + * 'power.ignore_children' flag unset. + */ + if (!parent->power.disable_depth + && !parent->power.ignore_children + && parent->power.runtime_status != RPM_ACTIVE) { + error = -EBUSY; + } else { + if (dev->power.runtime_status == RPM_SUSPENDED) + atomic_inc(&parent->power.child_count); + } + + spin_unlock_irq(&parent->power.lock); + + if (error) + goto out; + } + + out_set: + dev->power.runtime_status = status; + dev->power.runtime_error = 0; + out: + spin_unlock_irqrestore(&dev->power.lock, flags); + + if (notify_parent) + pm_request_idle(parent); + + return error; +} +EXPORT_SYMBOL_GPL(__pm_runtime_set_status); + +/** + * __pm_runtime_barrier - Cancel pending requests and wait for completions. + * @dev: Device to handle. + * + * Flush all pending requests for the device from pm_wq and wait for all + * run-time PM operations involving the device in progress to complete. + * + * Should be called under dev->power.lock with interrupts disabled. + */ +static void __pm_runtime_barrier(struct device *dev) +{ + pm_runtime_deactivate_timer(dev); + + if (dev->power.request_pending) { + dev->power.request = RPM_REQ_NONE; + spin_unlock_irq(&dev->power.lock); + + cancel_work_sync(&dev->power.work); + + spin_lock_irq(&dev->power.lock); + dev->power.request_pending = false; + } + + if (dev->power.runtime_status == RPM_SUSPENDING + || dev->power.runtime_status == RPM_RESUMING + || dev->power.idle_notification) { + DEFINE_WAIT(wait); + + /* Suspend, wake-up or idle notification in progress. */ + for (;;) { + prepare_to_wait(&dev->power.wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (dev->power.runtime_status != RPM_SUSPENDING + && dev->power.runtime_status != RPM_RESUMING + && !dev->power.idle_notification) + break; + spin_unlock_irq(&dev->power.lock); + + schedule(); + + spin_lock_irq(&dev->power.lock); + } + finish_wait(&dev->power.wait_queue, &wait); + } +} + +/** + * pm_runtime_barrier - Flush pending requests and wait for completions. + * @dev: Device to handle. + * + * Prevent the device from being suspended by incrementing its usage counter and + * if there's a pending resume request for the device, wake the device up. + * Next, make sure that all pending requests for the device have been flushed + * from pm_wq and wait for all run-time PM operations involving the device in + * progress to complete. + * + * Return value: + * 1, if there was a resume request pending and the device had to be woken up, + * 0, otherwise + */ +int pm_runtime_barrier(struct device *dev) +{ + int retval = 0; + + pm_runtime_get_noresume(dev); + spin_lock_irq(&dev->power.lock); + + if (dev->power.request_pending + && dev->power.request == RPM_REQ_RESUME) { + __pm_runtime_resume(dev, false); + retval = 1; + } + + __pm_runtime_barrier(dev); + + spin_unlock_irq(&dev->power.lock); + pm_runtime_put_noidle(dev); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_runtime_barrier); + +/** + * __pm_runtime_disable - Disable run-time PM of a device. + * @dev: Device to handle. + * @check_resume: If set, check if there's a resume request for the device. + * + * Increment power.disable_depth for the device and if was zero previously, + * cancel all pending run-time PM requests for the device and wait for all + * operations in progress to complete. The device can be either active or + * suspended after its run-time PM has been disabled. + * + * If @check_resume is set and there's a resume request pending when + * __pm_runtime_disable() is called and power.disable_depth is zero, the + * function will wake up the device before disabling its run-time PM. + */ +void __pm_runtime_disable(struct device *dev, bool check_resume) +{ + spin_lock_irq(&dev->power.lock); + + if (dev->power.disable_depth > 0) { + dev->power.disable_depth++; + goto out; + } + + /* + * Wake up the device if there's a resume request pending, because that + * means there probably is some I/O to process and disabling run-time PM + * shouldn't prevent the device from processing the I/O. + */ + if (check_resume && dev->power.request_pending + && dev->power.request == RPM_REQ_RESUME) { + /* + * Prevent suspends and idle notifications from being carried + * out after we have woken up the device. + */ + pm_runtime_get_noresume(dev); + + __pm_runtime_resume(dev, false); + + pm_runtime_put_noidle(dev); + } + + if (!dev->power.disable_depth++) + __pm_runtime_barrier(dev); + + out: + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(__pm_runtime_disable); + +/** + * pm_runtime_enable - Enable run-time PM of a device. + * @dev: Device to handle. + */ +void pm_runtime_enable(struct device *dev) +{ + unsigned long flags; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (dev->power.disable_depth > 0) + dev->power.disable_depth--; + else + dev_warn(dev, "Unbalanced %s!\n", __func__); + + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_runtime_enable); + +/** + * pm_runtime_init - Initialize run-time PM fields in given device object. + * @dev: Device object to initialize. + */ +void pm_runtime_init(struct device *dev) +{ + spin_lock_init(&dev->power.lock); + + dev->power.runtime_status = RPM_SUSPENDED; + dev->power.idle_notification = false; + + dev->power.disable_depth = 1; + atomic_set(&dev->power.usage_count, 0); + + dev->power.runtime_error = 0; + + atomic_set(&dev->power.child_count, 0); + pm_suspend_ignore_children(dev, false); + + dev->power.request_pending = false; + dev->power.request = RPM_REQ_NONE; + dev->power.deferred_resume = false; + INIT_WORK(&dev->power.work, pm_runtime_work); + + dev->power.timer_expires = 0; + setup_timer(&dev->power.suspend_timer, pm_suspend_timer_fn, + (unsigned long)dev); + + init_waitqueue_head(&dev->power.wait_queue); +} + +/** + * pm_runtime_remove - Prepare for removing a device from device hierarchy. + * @dev: Device object being removed from device hierarchy. + */ +void pm_runtime_remove(struct device *dev) +{ + __pm_runtime_disable(dev, false); + + /* Change the status back to 'suspended' to match the initial status. */ + if (dev->power.runtime_status == RPM_ACTIVE) + pm_runtime_set_suspended(dev); +} diff --git a/include/linux/pm.h b/include/linux/pm.h index b3f74764a586..2b6e20df0e52 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -22,6 +22,10 @@ #define _LINUX_PM_H #include +#include +#include +#include +#include /* * Callbacks for platform drivers to implement. @@ -165,6 +169,28 @@ typedef struct pm_message { * It is allowed to unregister devices while the above callbacks are being * executed. However, it is not allowed to unregister a device from within any * of its own callbacks. + * + * There also are the following callbacks related to run-time power management + * of devices: + * + * @runtime_suspend: Prepare the device for a condition in which it won't be + * able to communicate with the CPU(s) and RAM due to power management. + * This need not mean that the device should be put into a low power state. + * For example, if the device is behind a link which is about to be turned + * off, the device may remain at full power. If the device does go to low + * power and if device_may_wakeup(dev) is true, remote wake-up (i.e., a + * hardware mechanism allowing the device to request a change of its power + * state, such as PCI PME) should be enabled for it. + * + * @runtime_resume: Put the device into the fully active state in response to a + * wake-up event generated by hardware or at the request of software. If + * necessary, put the device into the full power state and restore its + * registers, so that it is fully operational. + * + * @runtime_idle: Device appears to be inactive and it might be put into a low + * power state if all of the necessary conditions are satisfied. Check + * these conditions and handle the device as appropriate, possibly queueing + * a suspend request for it. The return value is ignored by the PM core. */ struct dev_pm_ops { @@ -182,6 +208,9 @@ struct dev_pm_ops { int (*thaw_noirq)(struct device *dev); int (*poweroff_noirq)(struct device *dev); int (*restore_noirq)(struct device *dev); + int (*runtime_suspend)(struct device *dev); + int (*runtime_resume)(struct device *dev); + int (*runtime_idle)(struct device *dev); }; /** @@ -315,14 +344,80 @@ enum dpm_state { DPM_OFF_IRQ, }; +/** + * Device run-time power management status. + * + * These status labels are used internally by the PM core to indicate the + * current status of a device with respect to the PM core operations. They do + * not reflect the actual power state of the device or its status as seen by the + * driver. + * + * RPM_ACTIVE Device is fully operational. Indicates that the device + * bus type's ->runtime_resume() callback has completed + * successfully. + * + * RPM_SUSPENDED Device bus type's ->runtime_suspend() callback has + * completed successfully. The device is regarded as + * suspended. + * + * RPM_RESUMING Device bus type's ->runtime_resume() callback is being + * executed. + * + * RPM_SUSPENDING Device bus type's ->runtime_suspend() callback is being + * executed. + */ + +enum rpm_status { + RPM_ACTIVE = 0, + RPM_RESUMING, + RPM_SUSPENDED, + RPM_SUSPENDING, +}; + +/** + * Device run-time power management request types. + * + * RPM_REQ_NONE Do nothing. + * + * RPM_REQ_IDLE Run the device bus type's ->runtime_idle() callback + * + * RPM_REQ_SUSPEND Run the device bus type's ->runtime_suspend() callback + * + * RPM_REQ_RESUME Run the device bus type's ->runtime_resume() callback + */ + +enum rpm_request { + RPM_REQ_NONE = 0, + RPM_REQ_IDLE, + RPM_REQ_SUSPEND, + RPM_REQ_RESUME, +}; + struct dev_pm_info { pm_message_t power_state; - unsigned can_wakeup:1; - unsigned should_wakeup:1; + unsigned int can_wakeup:1; + unsigned int should_wakeup:1; enum dpm_state status; /* Owned by the PM core */ -#ifdef CONFIG_PM_SLEEP +#ifdef CONFIG_PM_SLEEP struct list_head entry; #endif +#ifdef CONFIG_PM_RUNTIME + struct timer_list suspend_timer; + unsigned long timer_expires; + struct work_struct work; + wait_queue_head_t wait_queue; + spinlock_t lock; + atomic_t usage_count; + atomic_t child_count; + unsigned int disable_depth:3; + unsigned int ignore_children:1; + unsigned int idle_notification:1; + unsigned int request_pending:1; + unsigned int deferred_resume:1; + enum rpm_request request; + enum rpm_status runtime_status; + int runtime_error; +#endif }; /* diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h new file mode 100644 index 000000000000..44087044910f --- /dev/null +++ b/include/linux/pm_runtime.h @@ -0,0 +1,114 @@ +/* + * pm_runtime.h - Device run-time power management helper functions. + * + * Copyright (C) 2009 Rafael J. Wysocki + * + * This file is released under the GPLv2. + */ + +#ifndef _LINUX_PM_RUNTIME_H +#define _LINUX_PM_RUNTIME_H + +#include +#include + +#ifdef CONFIG_PM_RUNTIME + +extern struct workqueue_struct *pm_wq; + +extern int pm_runtime_idle(struct device *dev); +extern int pm_runtime_suspend(struct device *dev); +extern int pm_runtime_resume(struct device *dev); +extern int pm_request_idle(struct device *dev); +extern int pm_schedule_suspend(struct device *dev, unsigned int delay); +extern int pm_request_resume(struct device *dev); +extern int __pm_runtime_get(struct device *dev, bool sync); +extern int __pm_runtime_put(struct device *dev, bool sync); +extern int __pm_runtime_set_status(struct device *dev, unsigned int status); +extern int pm_runtime_barrier(struct device *dev); +extern void pm_runtime_enable(struct device *dev); +extern void __pm_runtime_disable(struct device *dev, bool check_resume); + +static inline bool pm_children_suspended(struct device *dev) +{ + return dev->power.ignore_children + || !atomic_read(&dev->power.child_count); +} + +static inline void pm_suspend_ignore_children(struct device *dev, bool enable) +{ + dev->power.ignore_children = enable; +} + +static inline void pm_runtime_get_noresume(struct device *dev) +{ + atomic_inc(&dev->power.usage_count); +} + +static inline void pm_runtime_put_noidle(struct device *dev) +{ + atomic_add_unless(&dev->power.usage_count, -1, 0); +} + +#else /* !CONFIG_PM_RUNTIME */ + +static inline int pm_runtime_idle(struct device *dev) { return -ENOSYS; } +static inline int pm_runtime_suspend(struct device *dev) { return -ENOSYS; } +static inline int pm_runtime_resume(struct device *dev) { return 0; } +static inline int pm_request_idle(struct device *dev) { return -ENOSYS; } +static inline int pm_schedule_suspend(struct device *dev, unsigned int delay) +{ + return -ENOSYS; +} +static inline int pm_request_resume(struct device *dev) { return 0; } +static inline int __pm_runtime_get(struct device *dev, bool sync) { return 1; } +static inline int __pm_runtime_put(struct device *dev, bool sync) { return 0; } +static inline int __pm_runtime_set_status(struct device *dev, + unsigned int status) { return 0; } +static inline int pm_runtime_barrier(struct device *dev) { return 0; } +static inline void pm_runtime_enable(struct device *dev) {} +static inline void __pm_runtime_disable(struct device *dev, bool c) {} + +static inline bool pm_children_suspended(struct device *dev) { return false; } +static inline void pm_suspend_ignore_children(struct device *dev, bool en) {} +static inline void pm_runtime_get_noresume(struct device *dev) {} +static inline void pm_runtime_put_noidle(struct device *dev) {} + +#endif /* !CONFIG_PM_RUNTIME */ + +static inline int pm_runtime_get(struct device *dev) +{ + return __pm_runtime_get(dev, false); +} + +static inline int pm_runtime_get_sync(struct device *dev) +{ + return __pm_runtime_get(dev, true); +} + +static inline int pm_runtime_put(struct device *dev) +{ + return __pm_runtime_put(dev, false); +} + +static inline int pm_runtime_put_sync(struct device *dev) +{ + return __pm_runtime_put(dev, true); +} + +static inline int pm_runtime_set_active(struct device *dev) +{ + return __pm_runtime_set_status(dev, RPM_ACTIVE); +} + +static inline void pm_runtime_set_suspended(struct device *dev) +{ + __pm_runtime_set_status(dev, RPM_SUSPENDED); +} + +static inline void pm_runtime_disable(struct device *dev) +{ + __pm_runtime_disable(dev, true); +} + +#endif diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index 72067cbdb37f..91e09d3b2eb2 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -208,3 +208,17 @@ config APM_EMULATION random kernel OOPSes or reboots that don't seem to be related to anything, try disabling/enabling this option (or disabling/enabling APM in your BIOS). + +config PM_RUNTIME + bool "Run-time PM core functionality" + depends on PM + ---help--- + Enable functionality allowing I/O devices to be put into energy-saving + (low power) states at run time (or autosuspended) after a specified + period of inactivity and woken up in response to a hardware-generated + wake-up event or a driver's request. + + Hardware support is generally required for this functionality to work + and the bus type drivers of the buses the devices are on are + responsible for the actual handling of the autosuspend requests and + wake-up events. diff --git a/kernel/power/main.c b/kernel/power/main.c index f710e36930cc..347d2cc88cd0 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -11,6 +11,7 @@ #include #include #include +#include #include "power.h" @@ -217,8 +218,24 @@ static struct attribute_group attr_group = { .attrs = g, }; +#ifdef CONFIG_PM_RUNTIME +struct workqueue_struct *pm_wq; + +static int __init pm_start_workqueue(void) +{ + pm_wq = create_freezeable_workqueue("pm"); + + return pm_wq ? 0 : -ENOMEM; +} +#else +static inline int pm_start_workqueue(void) { return 0; } +#endif + static int __init pm_init(void) { + int error = pm_start_workqueue(); + if (error) + return error; power_kobj = kobject_create_and_add("power", NULL); if (!power_kobj) return -ENOMEM; -- cgit v1.2.3 From 36d47481b3824b661b464077db95d447984df799 Mon Sep 17 00:00:00 2001 From: Hiroshi Shimamoto Date: Tue, 25 Aug 2009 15:08:30 +0900 Subject: timekeeping: Fix invalid getboottime() value Don't use timespec_add_safe() with wall_to_monotonic, because wall_to_monotonic has negative values which will cause overflow in timespec_add_safe(). That makes btime in /proc/stat invalid. Signed-off-by: Hiroshi Shimamoto Cc: Martin Schwidefsky Cc: John Stultz Cc: Daniel Walker LKML-Reference: <4A937FDE.4050506@ct.jp.nec.com> Signed-off-by: Ingo Molnar --- kernel/time/timekeeping.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 03cbeb34d141..fb0f46fa1ecd 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -826,9 +826,11 @@ void update_wall_time(void) */ void getboottime(struct timespec *ts) { - struct timespec boottime; + struct timespec boottime = { + .tv_sec = wall_to_monotonic.tv_sec + total_sleep_time.tv_sec, + .tv_nsec = wall_to_monotonic.tv_nsec + total_sleep_time.tv_nsec + }; - boottime = timespec_add_safe(wall_to_monotonic, total_sleep_time); set_normalized_timespec(ts, -boottime.tv_sec, -boottime.tv_nsec); } -- cgit v1.2.3 From 90cba64a5f672a239f43ec5cb9a11b806887331e Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Tue, 25 Aug 2009 14:35:41 -0700 Subject: timer.c: Fix S/390 comments Fix typos and add omitted words. Signed-off-by: Randy Dunlap Cc: akpm Cc: linux390@de.ibm.com Cc: Martin Schwidefsky Cc: Heiko Carstens LKML-Reference: <20090825143541.43fc2ed8.randy.dunlap@oracle.com> Signed-off-by: Ingo Molnar --- kernel/timer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/timer.c b/kernel/timer.c index 33fc9d175f40..8e92be654dad 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -1023,8 +1023,8 @@ static inline void __run_timers(struct tvec_base *base) #ifdef CONFIG_NO_HZ /* * Find out when the next timer event is due to happen. This - * is used on S/390 to stop all activity when a cpus is idle. - * This functions needs to be called disabled. + * is used on S/390 to stop all activity when a CPU is idle. + * This function needs to be called with interrupts disabled. */ static unsigned long __next_timer_interrupt(struct tvec_base *base) { -- cgit v1.2.3 From 7285dd7fd375763bfb8ab1ac9cf3f1206f503c16 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 28 Aug 2009 20:25:24 +0200 Subject: clocksource: Resolve cpu hotplug dead lock with TSC unstable Martin Schwidefsky analyzed it: To register a clocksource the clocksource_mutex is acquired and if necessary timekeeping_notify is called to install the clocksource as the timekeeper clock. timekeeping_notify uses stop_machine which needs to take cpu_add_remove_lock mutex. Starting a new cpu is done with the cpu_add_remove_lock mutex held. native_cpu_up checks the tsc of the new cpu and if the tsc is no good clocksource_change_rating is called. Which needs the clocksource_mutex and the deadlock is complete. The solution is to replace the TSC via the clocksource watchdog mechanism. Mark the TSC as unstable and schedule the watchdog work so it gets removed in the watchdog thread context. Signed-off-by: Thomas Gleixner LKML-Reference: Cc: Martin Schwidefsky Cc: John Stultz --- arch/x86/kernel/tsc.c | 8 +++++--- include/linux/clocksource.h | 1 + kernel/time/clocksource.c | 33 ++++++++++++++++++++++++++++++--- 3 files changed, 36 insertions(+), 6 deletions(-) (limited to 'kernel') diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 968425422c46..fc3672a303d6 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -767,12 +767,14 @@ void mark_tsc_unstable(char *reason) { if (!tsc_unstable) { tsc_unstable = 1; - printk("Marking TSC unstable due to %s\n", reason); + printk(KERN_INFO "Marking TSC unstable due to %s\n", reason); /* Change only the rating, when not registered */ if (clocksource_tsc.mult) - clocksource_change_rating(&clocksource_tsc, 0); - else + clocksource_mark_unstable(&clocksource_tsc); + else { + clocksource_tsc.flags |= CLOCK_SOURCE_UNSTABLE; clocksource_tsc.rating = 0; + } } } diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 9ea40ff26f0e..83d2fbd81b93 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -277,6 +277,7 @@ extern struct clocksource* clocksource_get_next(void); extern void clocksource_change_rating(struct clocksource *cs, int rating); extern void clocksource_resume(void); extern struct clocksource * __init __weak clocksource_default_clock(void); +extern void clocksource_mark_unstable(struct clocksource *cs); #ifdef CONFIG_GENERIC_TIME_VSYSCALL extern void update_vsyscall(struct timespec *ts, struct clocksource *c); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index e0c86ad6e9fb..a0af4ffcb6e5 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -149,15 +149,42 @@ static void clocksource_watchdog_work(struct work_struct *work) kthread_run(clocksource_watchdog_kthread, NULL, "kwatchdog"); } -static void clocksource_unstable(struct clocksource *cs, int64_t delta) +static void __clocksource_unstable(struct clocksource *cs) { - printk(KERN_WARNING "Clocksource %s unstable (delta = %Ld ns)\n", - cs->name, delta); cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG); cs->flags |= CLOCK_SOURCE_UNSTABLE; schedule_work(&watchdog_work); } +static void clocksource_unstable(struct clocksource *cs, int64_t delta) +{ + printk(KERN_WARNING "Clocksource %s unstable (delta = %Ld ns)\n", + cs->name, delta); + __clocksource_unstable(cs); +} + +/** + * clocksource_mark_unstable - mark clocksource unstable via watchdog + * @cs: clocksource to be marked unstable + * + * This function is called instead of clocksource_change_rating from + * cpu hotplug code to avoid a deadlock between the clocksource mutex + * and the cpu hotplug mutex. It defers the update of the clocksource + * to the watchdog thread. + */ +void clocksource_mark_unstable(struct clocksource *cs) +{ + unsigned long flags; + + spin_lock_irqsave(&watchdog_lock, flags); + if (!(cs->flags & CLOCK_SOURCE_UNSTABLE)) { + if (list_empty(&cs->wd_list)) + list_add(&cs->wd_list, &watchdog_list); + __clocksource_unstable(cs); + } + spin_unlock_irqrestore(&watchdog_lock, flags); +} + static void clocksource_watchdog(unsigned long data) { struct clocksource *cs; -- cgit v1.2.3 From 2b022e3d4bf9885f781221c59d86283a2cdfc2ed Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Mon, 10 Aug 2009 10:48:59 +0800 Subject: timers: Add tracepoints for timer_list timers Add tracepoints which cover the timer life cycle. The tracepoints are integrated with the already existing debug_object debug points as far as possible. Based on patches from Mathieu: http://marc.info/?l=linux-kernel&m=123791201816247&w=2 and Anton: http://marc.info/?l=linux-kernel&m=124331396919301&w=2 [ tglx: Fixed timeout value in timer_start tracepoint, massaged comments and made the printk's more readable ] Signed-off-by: Xiao Guangrong Cc: Anton Blanchard Cc: Steven Rostedt Cc: Frederic Weisbecker Cc: Mathieu Desnoyers Cc: Peter Zijlstra Cc: KOSAKI Motohiro Cc: Zhaolei LKML-Reference: <4A7F8A9B.3040201@cn.fujitsu.com> Signed-off-by: Thomas Gleixner --- include/trace/events/timer.h | 137 +++++++++++++++++++++++++++++++++++++++++++ kernel/timer.c | 32 ++++++++-- 2 files changed, 165 insertions(+), 4 deletions(-) create mode 100644 include/trace/events/timer.h (limited to 'kernel') diff --git a/include/trace/events/timer.h b/include/trace/events/timer.h new file mode 100644 index 000000000000..725892a93b49 --- /dev/null +++ b/include/trace/events/timer.h @@ -0,0 +1,137 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM timer + +#if !defined(_TRACE_TIMER_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_TIMER_H + +#include +#include + +/** + * timer_init - called when the timer is initialized + * @timer: pointer to struct timer_list + */ +TRACE_EVENT(timer_init, + + TP_PROTO(struct timer_list *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("timer %p", __entry->timer) +); + +/** + * timer_start - called when the timer is started + * @timer: pointer to struct timer_list + * @expires: the timers expiry time + */ +TRACE_EVENT(timer_start, + + TP_PROTO(struct timer_list *timer, unsigned long expires), + + TP_ARGS(timer, expires), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( void *, function ) + __field( unsigned long, expires ) + __field( unsigned long, now ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->function = timer->function; + __entry->expires = expires; + __entry->now = jiffies; + ), + + TP_printk("timer %p: func %pf, expires %lu, timeout %ld", + __entry->timer, __entry->function, __entry->expires, + (long)__entry->expires - __entry->now) +); + +/** + * timer_expire_entry - called immediately before the timer callback + * @timer: pointer to struct timer_list + * + * Allows to determine the timer latency. + */ +TRACE_EVENT(timer_expire_entry, + + TP_PROTO(struct timer_list *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( unsigned long, now ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->now = jiffies; + ), + + TP_printk("timer %p: now %lu", __entry->timer, __entry->now) +); + +/** + * timer_expire_exit - called immediately after the timer callback returns + * @timer: pointer to struct timer_list + * + * When used in combination with the timer_expire_entry tracepoint we can + * determine the runtime of the timer callback function. + * + * NOTE: Do NOT derefernce timer in TP_fast_assign. The pointer might + * be invalid. We solely track the pointer. + */ +TRACE_EVENT(timer_expire_exit, + + TP_PROTO(struct timer_list *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field(void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("timer %p", __entry->timer) +); + +/** + * timer_cancel - called when the timer is canceled + * @timer: pointer to struct timer_list + */ +TRACE_EVENT(timer_cancel, + + TP_PROTO(struct timer_list *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("timer %p", __entry->timer) +); + +#endif /* _TRACE_TIMER_H */ + +/* This part must be outside protection */ +#include diff --git a/kernel/timer.c b/kernel/timer.c index 8e92be654dad..a7352b00703c 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -46,6 +46,9 @@ #include #include +#define CREATE_TRACE_POINTS +#include + u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES; EXPORT_SYMBOL(jiffies_64); @@ -521,6 +524,25 @@ static inline void debug_timer_activate(struct timer_list *timer) { } static inline void debug_timer_deactivate(struct timer_list *timer) { } #endif +static inline void debug_init(struct timer_list *timer) +{ + debug_timer_init(timer); + trace_timer_init(timer); +} + +static inline void +debug_activate(struct timer_list *timer, unsigned long expires) +{ + debug_timer_activate(timer); + trace_timer_start(timer, expires); +} + +static inline void debug_deactivate(struct timer_list *timer) +{ + debug_timer_deactivate(timer); + trace_timer_cancel(timer); +} + static void __init_timer(struct timer_list *timer, const char *name, struct lock_class_key *key) @@ -549,7 +571,7 @@ void init_timer_key(struct timer_list *timer, const char *name, struct lock_class_key *key) { - debug_timer_init(timer); + debug_init(timer); __init_timer(timer, name, key); } EXPORT_SYMBOL(init_timer_key); @@ -568,7 +590,7 @@ static inline void detach_timer(struct timer_list *timer, { struct list_head *entry = &timer->entry; - debug_timer_deactivate(timer); + debug_deactivate(timer); __list_del(entry->prev, entry->next); if (clear_pending) @@ -632,7 +654,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, goto out_unlock; } - debug_timer_activate(timer); + debug_activate(timer, expires); new_base = __get_cpu_var(tvec_bases); @@ -787,7 +809,7 @@ void add_timer_on(struct timer_list *timer, int cpu) BUG_ON(timer_pending(timer) || !timer->function); spin_lock_irqsave(&base->lock, flags); timer_set_base(timer, base); - debug_timer_activate(timer); + debug_activate(timer, timer->expires); if (time_before(timer->expires, base->next_timer) && !tbase_get_deferrable(timer->base)) base->next_timer = timer->expires; @@ -1000,7 +1022,9 @@ static inline void __run_timers(struct tvec_base *base) */ lock_map_acquire(&lockdep_map); + trace_timer_expire_entry(timer); fn(data); + trace_timer_expire_exit(timer); lock_map_release(&lockdep_map); -- cgit v1.2.3 From c6a2a1770245f654f35f60e1458d4356680f9519 Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Mon, 10 Aug 2009 10:51:23 +0800 Subject: hrtimer: Add tracepoint for hrtimers Add tracepoints which cover the life cycle of a hrtimer. The tracepoints are integrated with the already existing debug_object debug points as far as possible. [ tglx: Fixed comments, made output conistent, easier to read and parse. Fixed output for 32bit archs which do not use the scalar representation of ktime_t. Hand current time to trace_hrtimer_expiry_entry instead of calling get_time() inside of the trace assignment. ] Signed-off-by: Xiao Guangrong Cc: Steven Rostedt Cc: Frederic Weisbecker Cc: Mathieu Desnoyers Cc: Anton Blanchard Cc: Peter Zijlstra Cc: KOSAKI Motohiro Cc: Zhaolei LKML-Reference: <4A7F8B2B.5020908@cn.fujitsu.com> Signed-off-by: Thomas Gleixner --- include/trace/events/timer.h | 139 +++++++++++++++++++++++++++++++++++++++++++ kernel/hrtimer.c | 40 ++++++++++--- 2 files changed, 171 insertions(+), 8 deletions(-) (limited to 'kernel') diff --git a/include/trace/events/timer.h b/include/trace/events/timer.h index 725892a93b49..df3c07fa0cb8 100644 --- a/include/trace/events/timer.h +++ b/include/trace/events/timer.h @@ -5,6 +5,7 @@ #define _TRACE_TIMER_H #include +#include #include /** @@ -131,6 +132,144 @@ TRACE_EVENT(timer_cancel, TP_printk("timer %p", __entry->timer) ); +/** + * hrtimer_init - called when the hrtimer is initialized + * @timer: pointer to struct hrtimer + * @clockid: the hrtimers clock + * @mode: the hrtimers mode + */ +TRACE_EVENT(hrtimer_init, + + TP_PROTO(struct hrtimer *timer, clockid_t clockid, + enum hrtimer_mode mode), + + TP_ARGS(timer, clockid, mode), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( clockid_t, clockid ) + __field( enum hrtimer_mode, mode ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->clockid = clockid; + __entry->mode = mode; + ), + + TP_printk("hrtimer %p, clockid %s, mode %s", __entry->timer, + __entry->clockid == CLOCK_REALTIME ? + "CLOCK_REALTIME" : "CLOCK_MONOTONIC", + __entry->mode == HRTIMER_MODE_ABS ? + "HRTIMER_MODE_ABS" : "HRTIMER_MODE_REL") +); + +/** + * hrtimer_start - called when the hrtimer is started + * @timer: pointer to struct hrtimer + */ +TRACE_EVENT(hrtimer_start, + + TP_PROTO(struct hrtimer *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( void *, function ) + __field( s64, expires ) + __field( s64, softexpires ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->function = timer->function; + __entry->expires = hrtimer_get_expires(timer).tv64; + __entry->softexpires = hrtimer_get_softexpires(timer).tv64; + ), + + TP_printk("hrtimer %p, func %pf, expires %llu, softexpires %llu", + __entry->timer, __entry->function, + (unsigned long long)ktime_to_ns((ktime_t) { + .tv64 = __entry->expires }), + (unsigned long long)ktime_to_ns((ktime_t) { + .tv64 = __entry->softexpires })) +); + +/** + * htimmer_expire_entry - called immediately before the hrtimer callback + * @timer: pointer to struct hrtimer + * @now: pointer to variable which contains current time of the + * timers base. + * + * Allows to determine the timer latency. + */ +TRACE_EVENT(hrtimer_expire_entry, + + TP_PROTO(struct hrtimer *timer, ktime_t *now), + + TP_ARGS(timer, now), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( s64, now ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->now = now->tv64; + ), + + TP_printk("hrtimer %p, now %llu", __entry->timer, + (unsigned long long)ktime_to_ns((ktime_t) { + .tv64 = __entry->now })) + ); + +/** + * hrtimer_expire_exit - called immediately after the hrtimer callback returns + * @timer: pointer to struct hrtimer + * + * When used in combination with the hrtimer_expire_entry tracepoint we can + * determine the runtime of the callback function. + */ +TRACE_EVENT(hrtimer_expire_exit, + + TP_PROTO(struct hrtimer *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("hrtimer %p", __entry->timer) +); + +/** + * hrtimer_cancel - called when the hrtimer is canceled + * @timer: pointer to struct hrtimer + */ +TRACE_EVENT(hrtimer_cancel, + + TP_PROTO(struct hrtimer *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("hrtimer %p", __entry->timer) +); + #endif /* _TRACE_TIMER_H */ /* This part must be outside protection */ diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index e2f91ecc01a8..b44d1b07377b 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -48,6 +48,8 @@ #include +#include + /* * The timer bases: * @@ -441,6 +443,26 @@ static inline void debug_hrtimer_activate(struct hrtimer *timer) { } static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { } #endif +static inline void +debug_init(struct hrtimer *timer, clockid_t clockid, + enum hrtimer_mode mode) +{ + debug_hrtimer_init(timer); + trace_hrtimer_init(timer, clockid, mode); +} + +static inline void debug_activate(struct hrtimer *timer) +{ + debug_hrtimer_activate(timer); + trace_hrtimer_start(timer); +} + +static inline void debug_deactivate(struct hrtimer *timer) +{ + debug_hrtimer_deactivate(timer); + trace_hrtimer_cancel(timer); +} + /* High resolution timer related functions */ #ifdef CONFIG_HIGH_RES_TIMERS @@ -797,7 +819,7 @@ static int enqueue_hrtimer(struct hrtimer *timer, struct hrtimer *entry; int leftmost = 1; - debug_hrtimer_activate(timer); + debug_activate(timer); /* * Find the right place in the rbtree: @@ -883,7 +905,7 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base) * reprogramming happens in the interrupt handler. This is a * rare case and less expensive than a smp call. */ - debug_hrtimer_deactivate(timer); + debug_deactivate(timer); timer_stats_hrtimer_clear_start_info(timer); reprogram = base->cpu_base == &__get_cpu_var(hrtimer_bases); __remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, @@ -1116,7 +1138,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, void hrtimer_init(struct hrtimer *timer, clockid_t clock_id, enum hrtimer_mode mode) { - debug_hrtimer_init(timer); + debug_init(timer, clock_id, mode); __hrtimer_init(timer, clock_id, mode); } EXPORT_SYMBOL_GPL(hrtimer_init); @@ -1140,7 +1162,7 @@ int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp) } EXPORT_SYMBOL_GPL(hrtimer_get_res); -static void __run_hrtimer(struct hrtimer *timer) +static void __run_hrtimer(struct hrtimer *timer, ktime_t *now) { struct hrtimer_clock_base *base = timer->base; struct hrtimer_cpu_base *cpu_base = base->cpu_base; @@ -1149,7 +1171,7 @@ static void __run_hrtimer(struct hrtimer *timer) WARN_ON(!irqs_disabled()); - debug_hrtimer_deactivate(timer); + debug_deactivate(timer); __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0); timer_stats_account_hrtimer(timer); fn = timer->function; @@ -1160,7 +1182,9 @@ static void __run_hrtimer(struct hrtimer *timer) * the timer base. */ spin_unlock(&cpu_base->lock); + trace_hrtimer_expire_entry(timer, now); restart = fn(timer); + trace_hrtimer_expire_exit(timer); spin_lock(&cpu_base->lock); /* @@ -1271,7 +1295,7 @@ void hrtimer_interrupt(struct clock_event_device *dev) break; } - __run_hrtimer(timer); + __run_hrtimer(timer, &basenow); } base++; } @@ -1393,7 +1417,7 @@ void hrtimer_run_queues(void) hrtimer_get_expires_tv64(timer)) break; - __run_hrtimer(timer); + __run_hrtimer(timer, &base->softirq_time); } spin_unlock(&cpu_base->lock); } @@ -1569,7 +1593,7 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base, while ((node = rb_first(&old_base->active))) { timer = rb_entry(node, struct hrtimer, node); BUG_ON(hrtimer_callback_running(timer)); - debug_hrtimer_deactivate(timer); + debug_deactivate(timer); /* * Mark it as STATE_MIGRATE not INACTIVE otherwise the -- cgit v1.2.3 From 3f0a525ebf4b8ef041a332bbe4a73aee94bb064b Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Mon, 10 Aug 2009 10:52:30 +0800 Subject: itimers: Add tracepoints for itimer Add tracepoints for all itimer variants: ITIMER_REAL, ITIMER_VIRTUAL and ITIMER_PROF. [ tglx: Fixed comments and made the output more readable, parseable and consistent. Replaced pid_vnr by pid_nr because the hrtimer callback can happen in any namespace ] Signed-off-by: Xiao Guangrong Cc: Steven Rostedt Cc: Frederic Weisbecker Cc: Mathieu Desnoyers Cc: Anton Blanchard Cc: Peter Zijlstra Cc: KOSAKI Motohiro Cc: Zhaolei LKML-Reference: <4A7F8B6E.2010109@cn.fujitsu.com> Signed-off-by: Thomas Gleixner --- include/trace/events/timer.h | 66 ++++++++++++++++++++++++++++++++++++++++++++ kernel/itimer.c | 5 ++++ kernel/posix-cpu-timers.c | 7 ++++- 3 files changed, 77 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/include/trace/events/timer.h b/include/trace/events/timer.h index df3c07fa0cb8..1844c48d640e 100644 --- a/include/trace/events/timer.h +++ b/include/trace/events/timer.h @@ -270,6 +270,72 @@ TRACE_EVENT(hrtimer_cancel, TP_printk("hrtimer %p", __entry->timer) ); +/** + * itimer_state - called when itimer is started or canceled + * @which: name of the interval timer + * @value: the itimers value, itimer is canceled if value->it_value is + * zero, otherwise it is started + * @expires: the itimers expiry time + */ +TRACE_EVENT(itimer_state, + + TP_PROTO(int which, const struct itimerval *const value, + cputime_t expires), + + TP_ARGS(which, value, expires), + + TP_STRUCT__entry( + __field( int, which ) + __field( cputime_t, expires ) + __field( long, value_sec ) + __field( long, value_usec ) + __field( long, interval_sec ) + __field( long, interval_usec ) + ), + + TP_fast_assign( + __entry->which = which; + __entry->expires = expires; + __entry->value_sec = value->it_value.tv_sec; + __entry->value_usec = value->it_value.tv_usec; + __entry->interval_sec = value->it_interval.tv_sec; + __entry->interval_usec = value->it_interval.tv_usec; + ), + + TP_printk("which %d, expires %lu, it_value %lu.%lu, it_interval %lu.%lu", + __entry->which, __entry->expires, + __entry->value_sec, __entry->value_usec, + __entry->interval_sec, __entry->interval_usec) +); + +/** + * itimer_expire - called when itimer expires + * @which: type of the interval timer + * @pid: pid of the process which owns the timer + * @now: current time, used to calculate the latency of itimer + */ +TRACE_EVENT(itimer_expire, + + TP_PROTO(int which, struct pid *pid, cputime_t now), + + TP_ARGS(which, pid, now), + + TP_STRUCT__entry( + __field( int , which ) + __field( pid_t, pid ) + __field( cputime_t, now ) + ), + + TP_fast_assign( + __entry->which = which; + __entry->now = now; + __entry->pid = pid_nr(pid); + ), + + TP_printk("which %d, pid %d, now %lu", __entry->which, + (int) __entry->pid, __entry->now) +); + #endif /* _TRACE_TIMER_H */ /* This part must be outside protection */ diff --git a/kernel/itimer.c b/kernel/itimer.c index 8078a32d3b10..b03451ede528 100644 --- a/kernel/itimer.c +++ b/kernel/itimer.c @@ -12,6 +12,7 @@ #include #include #include +#include #include @@ -122,6 +123,7 @@ enum hrtimer_restart it_real_fn(struct hrtimer *timer) struct signal_struct *sig = container_of(timer, struct signal_struct, real_timer); + trace_itimer_expire(ITIMER_REAL, sig->leader_pid, 0); kill_pid_info(SIGALRM, SEND_SIG_PRIV, sig->leader_pid); return HRTIMER_NORESTART; @@ -166,6 +168,8 @@ static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, } it->expires = nval; it->incr = ninterval; + trace_itimer_state(clock_id == CPUCLOCK_VIRT ? + ITIMER_VIRTUAL : ITIMER_PROF, value, nval); spin_unlock_irq(&tsk->sighand->siglock); @@ -217,6 +221,7 @@ again: } else tsk->signal->it_real_incr.tv64 = 0; + trace_itimer_state(ITIMER_REAL, value, 0); spin_unlock_irq(&tsk->sighand->siglock); break; case ITIMER_VIRTUAL: diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index 12161f74744e..5c9dc228747b 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -8,6 +8,7 @@ #include #include #include +#include /* * Called after updating RLIMIT_CPU to set timer expiration if necessary. @@ -1090,9 +1091,13 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, cputime_one_jiffy); it->error -= onecputick; } - } else + } else { it->expires = cputime_zero; + } + trace_itimer_expire(signo == SIGPROF ? + ITIMER_PROF : ITIMER_VIRTUAL, + tsk->signal->leader_pid, cur_time); __group_send_sig_info(signo, SEND_SIG_PRIV, tsk); } -- cgit v1.2.3 From 69575d388603365f2afbf4166df93152df59b165 Mon Sep 17 00:00:00 2001 From: Shane Wang Date: Tue, 1 Sep 2009 18:25:07 -0700 Subject: x86, intel_txt: clean up the impact on generic code, unbreak non-x86 Move tboot.h from asm to linux to fix the build errors of intel_txt patch on non-X86 platforms. Remove the tboot code from generic code init/main.c and kernel/cpu.c. Signed-off-by: Shane Wang Signed-off-by: H. Peter Anvin --- arch/x86/Kconfig | 4 + arch/x86/include/asm/tboot.h | 197 ------------------------------------------ arch/x86/kernel/reboot.c | 3 +- arch/x86/kernel/setup.c | 3 +- arch/x86/kernel/smpboot.c | 2 +- arch/x86/kernel/tboot.c | 58 ++++++++++--- drivers/acpi/acpica/hwsleep.c | 2 +- drivers/pci/dmar.c | 2 +- drivers/pci/intel-iommu.c | 2 +- include/linux/tboot.h | 162 ++++++++++++++++++++++++++++++++++ init/main.c | 3 - kernel/cpu.c | 6 +- security/Kconfig | 2 +- 13 files changed, 221 insertions(+), 225 deletions(-) delete mode 100644 arch/x86/include/asm/tboot.h create mode 100644 include/linux/tboot.h (limited to 'kernel') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 738bdc6b0f8b..b66f2102c35d 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -178,6 +178,10 @@ config ARCH_SUPPORTS_OPTIMIZED_INLINING config ARCH_SUPPORTS_DEBUG_PAGEALLOC def_bool y +config HAVE_INTEL_TXT + def_bool y + depends on EXPERIMENTAL && DMAR && ACPI + # Use the generic interrupt handling code in kernel/irq/: config GENERIC_HARDIRQS bool diff --git a/arch/x86/include/asm/tboot.h b/arch/x86/include/asm/tboot.h deleted file mode 100644 index b13929d4e5f4..000000000000 --- a/arch/x86/include/asm/tboot.h +++ /dev/null @@ -1,197 +0,0 @@ -/* - * tboot.h: shared data structure with tboot and kernel and functions - * used by kernel for runtime support of Intel(R) Trusted - * Execution Technology - * - * Copyright (c) 2006-2009, Intel Corporation - * - * This program is free software; you can redistribute it and/or modify it - * under the terms and conditions of the GNU General Public License, - * version 2, as published by the Free Software Foundation. - * - * This program is distributed in the hope it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for - * more details. - * - * You should have received a copy of the GNU General Public License along with - * this program; if not, write to the Free Software Foundation, Inc., - * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. - * - */ - -#ifndef _ASM_TBOOT_H -#define _ASM_TBOOT_H - -#include - -/* these must have the values from 0-5 in this order */ -enum { - TB_SHUTDOWN_REBOOT = 0, - TB_SHUTDOWN_S5, - TB_SHUTDOWN_S4, - TB_SHUTDOWN_S3, - TB_SHUTDOWN_HALT, - TB_SHUTDOWN_WFS -}; - -#ifdef CONFIG_INTEL_TXT - -/* used to communicate between tboot and the launched kernel */ - -#define TB_KEY_SIZE 64 /* 512 bits */ - -#define MAX_TB_MAC_REGIONS 32 - -struct tboot_mac_region { - u64 start; /* must be 64 byte -aligned */ - u32 size; /* must be 64 byte -granular */ -} __packed; - -/* GAS - Generic Address Structure (ACPI 2.0+) */ -struct tboot_acpi_generic_address { - u8 space_id; - u8 bit_width; - u8 bit_offset; - u8 access_width; - u64 address; -} __packed; - -/* - * combines Sx info from FADT and FACS tables per ACPI 2.0+ spec - * (http://www.acpi.info/) - */ -struct tboot_acpi_sleep_info { - struct tboot_acpi_generic_address pm1a_cnt_blk; - struct tboot_acpi_generic_address pm1b_cnt_blk; - struct tboot_acpi_generic_address pm1a_evt_blk; - struct tboot_acpi_generic_address pm1b_evt_blk; - u16 pm1a_cnt_val; - u16 pm1b_cnt_val; - u64 wakeup_vector; - u32 vector_width; - u64 kernel_s3_resume_vector; -} __packed; - -/* - * shared memory page used for communication between tboot and kernel - */ -struct tboot { - /* - * version 3+ fields: - */ - - /* TBOOT_UUID */ - u8 uuid[16]; - - /* version number: 5 is current */ - u32 version; - - /* physical addr of tb_log_t log */ - u32 log_addr; - - /* - * physical addr of entry point for tboot shutdown and - * type of shutdown (TB_SHUTDOWN_*) being requested - */ - u32 shutdown_entry; - u32 shutdown_type; - - /* kernel-specified ACPI info for Sx shutdown */ - struct tboot_acpi_sleep_info acpi_sinfo; - - /* tboot location in memory (physical) */ - u32 tboot_base; - u32 tboot_size; - - /* memory regions (phys addrs) for tboot to MAC on S3 */ - u8 num_mac_regions; - struct tboot_mac_region mac_regions[MAX_TB_MAC_REGIONS]; - - - /* - * version 4+ fields: - */ - - /* symmetric key for use by kernel; will be encrypted on S3 */ - u8 s3_key[TB_KEY_SIZE]; - - - /* - * version 5+ fields: - */ - - /* used to 4byte-align num_in_wfs */ - u8 reserved_align[3]; - - /* number of processors in wait-for-SIPI */ - u32 num_in_wfs; -} __packed; - -/* - * UUID for tboot data struct to facilitate matching - * defined as {663C8DFF-E8B3-4b82-AABF-19EA4D057A08} by tboot, which is - * represented as {} in the char array used here - */ -#define TBOOT_UUID {0xff, 0x8d, 0x3c, 0x66, 0xb3, 0xe8, 0x82, 0x4b, 0xbf,\ - 0xaa, 0x19, 0xea, 0x4d, 0x5, 0x7a, 0x8} - -extern struct tboot *tboot; - -static inline int tboot_enabled(void) -{ - return tboot != NULL; -} - -extern void tboot_probe(void); -extern void tboot_create_trampoline(void); -extern void tboot_shutdown(u32 shutdown_type); -extern void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control); -extern int tboot_wait_for_aps(int num_aps); -extern struct acpi_table_header *tboot_get_dmar_table( - struct acpi_table_header *dmar_tbl); -extern int tboot_force_iommu(void); - -#else /* CONFIG_INTEL_TXT */ - -static inline int tboot_enabled(void) -{ - return 0; -} - -static inline void tboot_probe(void) -{ -} - -static inline void tboot_create_trampoline(void) -{ -} - -static inline void tboot_shutdown(u32 shutdown_type) -{ -} - -static inline void tboot_sleep(u8 sleep_state, u32 pm1a_control, - u32 pm1b_control) -{ -} - -static inline int tboot_wait_for_aps(int num_aps) -{ - return 0; -} - -static inline struct acpi_table_header *tboot_get_dmar_table( - struct acpi_table_header *dmar_tbl) -{ - return dmar_tbl; -} - -static inline int tboot_force_iommu(void) -{ - return 0; -} - -#endif /* !CONFIG_INTEL_TXT */ - -#endif /* _ASM_TBOOT_H */ diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 9de01c5d9794..18ce5c04242a 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -3,6 +3,7 @@ #include #include #include +#include #include #include #include @@ -24,8 +25,6 @@ # include #endif -#include - /* * Power off function, if any */ diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 80d6e9e32483..6ce0d6f38f7f 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -66,6 +66,7 @@ #include #include +#include #include