From 5cd7376200be7b8bab085557ff5876b04bd84191 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 15 Jan 2009 15:46:08 +0100 Subject: fix: crash: IP: __bitmap_intersects+0x48/0x73 -tip testing found this crash: > [ 35.258515] calling acpi_cpufreq_init+0x0/0x127 @ 1 > [ 35.264127] BUG: unable to handle kernel NULL pointer dereference at (null) > [ 35.267554] IP: [] __bitmap_intersects+0x48/0x73 > [ 35.267554] PGD 0 > [ 35.267554] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c is still broken: there's no allocation of the variable mask, so we pass in an uninitialized cmd.mask field to drv_read(), which then passes it to the scheduler which then crashes ... Switch it over to the much simpler constant-cpumask-pointers approach. Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) (limited to 'arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c') diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index 6f11e029e8c5..019276717a7f 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -145,7 +145,7 @@ typedef union { struct drv_cmd { unsigned int type; - cpumask_var_t mask; + const struct cpumask *mask; drv_addr_union addr; u32 val; }; @@ -235,8 +235,7 @@ static u32 get_cur_val(const struct cpumask *mask) return 0; } - cpumask_copy(cmd.mask, mask); - + cmd.mask = mask; drv_read(&cmd); dprintk("get_cur_val = %u\n", cmd.val); @@ -403,9 +402,6 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy, return -ENODEV; } - if (unlikely(!alloc_cpumask_var(&cmd.mask, GFP_KERNEL))) - return -ENOMEM; - perf = data->acpi_data; result = cpufreq_frequency_table_target(policy, data->freq_table, @@ -450,9 +446,9 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy, /* cpufreq holds the hotplug lock, so we are safe from here on */ if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY) - cpumask_and(cmd.mask, cpu_online_mask, policy->cpus); + cmd.mask = policy->cpus; else - cpumask_copy(cmd.mask, cpumask_of(policy->cpu)); + cmd.mask = cpumask_of(policy->cpu); freqs.old = perf->states[perf->state].core_frequency * 1000; freqs.new = data->freq_table[next_state].frequency; @@ -479,7 +475,6 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy, perf->state = next_perf_state; out: - free_cpumask_var(cmd.mask); return result; } -- cgit v1.2.3 From 6eb714c63ed5bd663627f7dda8c4d5258f3b64ef Mon Sep 17 00:00:00 2001 From: Mike Travis Date: Fri, 16 Jan 2009 15:31:15 -0800 Subject: cpufreq: use work_on_cpu in acpi-cpufreq.c for drv_read and drv_write Impact: use new work_on_cpu function to reduce stack usage Replace the saving of current->cpus_allowed and set_cpus_allowed_ptr() with a work_on_cpu function for drv_read() and drv_write(). Basically converts do_drv_{read,write} into "work_on_cpu" functions that are now called by drv_read and drv_write. Note: This patch basically reverts 50c668d6 which reverted 7503bfba, now that the work_on_cpu() function is more stable. Signed-off-by: Mike Travis Acked-by: Rusty Russell Tested-by: Dieter Ries Tested-by: Maciej Rutecki Cc: Dave Jones Cc: --- arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) (limited to 'arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c') diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index 019276717a7f..4b1c319d30c3 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -150,8 +150,9 @@ struct drv_cmd { u32 val; }; -static void do_drv_read(struct drv_cmd *cmd) +static long do_drv_read(void *_cmd) { + struct drv_cmd *cmd = _cmd; u32 h; switch (cmd->type) { @@ -166,10 +167,12 @@ static void do_drv_read(struct drv_cmd *cmd) default: break; } + return 0; } -static void do_drv_write(struct drv_cmd *cmd) +static long do_drv_write(void *_cmd) { + struct drv_cmd *cmd = _cmd; u32 lo, hi; switch (cmd->type) { @@ -186,30 +189,23 @@ static void do_drv_write(struct drv_cmd *cmd) default: break; } + return 0; } static void drv_read(struct drv_cmd *cmd) { - cpumask_t saved_mask = current->cpus_allowed; cmd->val = 0; - set_cpus_allowed_ptr(current, cmd->mask); - do_drv_read(cmd); - set_cpus_allowed_ptr(current, &saved_mask); + work_on_cpu(cpumask_any(cmd->mask), do_drv_read, cmd); } static void drv_write(struct drv_cmd *cmd) { - cpumask_t saved_mask = current->cpus_allowed; unsigned int i; for_each_cpu(i, cmd->mask) { - set_cpus_allowed_ptr(current, cpumask_of(i)); - do_drv_write(cmd); + work_on_cpu(i, do_drv_write, cmd); } - - set_cpus_allowed_ptr(current, &saved_mask); - return; } static u32 get_cur_val(const struct cpumask *mask) @@ -367,7 +363,7 @@ static unsigned int get_cur_freq_on_cpu(unsigned int cpu) return freq; } -static unsigned int check_freqs(const cpumask_t *mask, unsigned int freq, +static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq, struct acpi_cpufreq_data *data) { unsigned int cur_freq; -- cgit v1.2.3 From b36128c830a8f5bd7d4981f5b0b69950f5928ee6 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Fri, 20 Feb 2009 16:29:08 +0900 Subject: alloc_percpu: change percpu_ptr to per_cpu_ptr Impact: cleanup There are two allocated per-cpu accessor macros with almost identical spelling. The original and far more popular is per_cpu_ptr (44 files), so change over the other 4 files. tj: kill percpu_ptr() and update UP too Signed-off-by: Rusty Russell Cc: mingo@redhat.com Cc: lenb@kernel.org Cc: cpufreq@vger.kernel.org Signed-off-by: Tejun Heo --- arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 2 +- drivers/acpi/processor_perflib.c | 4 ++-- include/linux/percpu.h | 23 +++++++++++------------ kernel/sched.c | 6 +++--- kernel/stop_machine.c | 2 +- 5 files changed, 18 insertions(+), 19 deletions(-) (limited to 'arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c') diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index 4b1c319d30c3..22590cf688ae 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -601,7 +601,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) if (!data) return -ENOMEM; - data->acpi_data = percpu_ptr(acpi_perf_data, cpu); + data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu); per_cpu(drv_data, cpu) = data; if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c index 9cc769b587ff..68fd3d292799 100644 --- a/drivers/acpi/processor_perflib.c +++ b/drivers/acpi/processor_perflib.c @@ -516,12 +516,12 @@ int acpi_processor_preregister_performance( continue; } - if (!performance || !percpu_ptr(performance, i)) { + if (!performance || !per_cpu_ptr(performance, i)) { retval = -EINVAL; continue; } - pr->performance = percpu_ptr(performance, i); + pr->performance = per_cpu_ptr(performance, i); cpumask_set_cpu(i, pr->performance->shared_cpu_map); if (acpi_processor_get_psd(pr)) { retval = -EINVAL; diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 3577ffd90d45..c80cfe1260ec 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -81,23 +81,13 @@ struct percpu_data { }; #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata) -/* - * Use this to get to a cpu's version of the per-cpu object dynamically - * allocated. Non-atomic access to the current CPU's version should - * probably be combined with get_cpu()/put_cpu(). - */ -#define percpu_ptr(ptr, cpu) \ -({ \ - struct percpu_data *__p = __percpu_disguise(ptr); \ - (__typeof__(ptr))__p->ptrs[(cpu)]; \ -}) extern void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask); extern void percpu_free(void *__pdata); #else /* CONFIG_SMP */ -#define percpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) +#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) static __always_inline void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask) { @@ -122,6 +112,15 @@ static inline void percpu_free(void *__pdata) cpu_possible_map) #define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type)) #define free_percpu(ptr) percpu_free((ptr)) -#define per_cpu_ptr(ptr, cpu) percpu_ptr((ptr), (cpu)) +/* + * Use this to get to a cpu's version of the per-cpu object dynamically + * allocated. Non-atomic access to the current CPU's version should + * probably be combined with get_cpu()/put_cpu(). + */ +#define per_cpu_ptr(ptr, cpu) \ +({ \ + struct percpu_data *__p = __percpu_disguise(ptr); \ + (__typeof__(ptr))__p->ptrs[(cpu)]; \ +}) #endif /* __LINUX_PERCPU_H */ diff --git a/kernel/sched.c b/kernel/sched.c index fc17fd91ab57..9d30ac956328 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -9472,7 +9472,7 @@ cpuacct_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp) static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu) { - u64 *cpuusage = percpu_ptr(ca->cpuusage, cpu); + u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); u64 data; #ifndef CONFIG_64BIT @@ -9491,7 +9491,7 @@ static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu) static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val) { - u64 *cpuusage = percpu_ptr(ca->cpuusage, cpu); + u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); #ifndef CONFIG_64BIT /* @@ -9587,7 +9587,7 @@ static void cpuacct_charge(struct task_struct *tsk, u64 cputime) ca = task_ca(tsk); for (; ca; ca = ca->parent) { - u64 *cpuusage = percpu_ptr(ca->cpuusage, cpu); + u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); *cpuusage += cputime; } } diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 0cd415ee62a2..74541ca49536 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -170,7 +170,7 @@ int __stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus) * doesn't hit this CPU until we're ready. */ get_cpu(); for_each_online_cpu(i) { - sm_work = percpu_ptr(stop_machine_work, i); + sm_work = per_cpu_ptr(stop_machine_work, i); INIT_WORK(sm_work, stop_cpu); queue_work_on(i, stop_machine_wq, sm_work); } -- cgit v1.2.3 From 3a58df35a64a1e0ac32c30ea629a513dec2fe711 Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Sat, 17 Jan 2009 22:36:14 -0500 Subject: [CPUFREQ] checkpatch cleanups for acpi-cpufreq Signed-off-by: Dave Jones --- arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 36 +++++++++++++++--------------- 1 file changed, 18 insertions(+), 18 deletions(-) (limited to 'arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c') diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index 4b1c319d30c3..3babe1f1e912 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -1,5 +1,5 @@ /* - * acpi-cpufreq.c - ACPI Processor P-States Driver ($Revision: 1.4 $) + * acpi-cpufreq.c - ACPI Processor P-States Driver * * Copyright (C) 2001, 2002 Andy Grover * Copyright (C) 2001, 2002 Paul Diefenbaugh @@ -36,16 +36,18 @@ #include #include +#include +#include +#include + #include -#include #include #include #include -#include -#include -#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "acpi-cpufreq", msg) +#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \ + "acpi-cpufreq", msg) MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski"); MODULE_DESCRIPTION("ACPI Processor P-States Driver"); @@ -95,7 +97,7 @@ static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data) perf = data->acpi_data; - for (i=0; istate_count; i++) { + for (i = 0; i < perf->state_count; i++) { if (value == perf->states[i].status) return data->freq_table[i].frequency; } @@ -110,7 +112,7 @@ static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data) msr &= INTEL_MSR_RANGE; perf = data->acpi_data; - for (i=0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) { + for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) { if (msr == perf->states[data->freq_table[i].index].status) return data->freq_table[i].frequency; } @@ -138,15 +140,13 @@ struct io_addr { u8 bit_width; }; -typedef union { - struct msr_addr msr; - struct io_addr io; -} drv_addr_union; - struct drv_cmd { unsigned int type; const struct cpumask *mask; - drv_addr_union addr; + union { + struct msr_addr msr; + struct io_addr io; + } addr; u32 val; }; @@ -369,7 +369,7 @@ static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq, unsigned int cur_freq; unsigned int i; - for (i=0; i<100; i++) { + for (i = 0; i < 100; i++) { cur_freq = extract_freq(get_cur_val(mask), data); if (cur_freq == freq) return 1; @@ -494,7 +494,7 @@ acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu) unsigned long freq; unsigned long freqn = perf->states[0].core_frequency * 1000; - for (i=0; i<(perf->state_count-1); i++) { + for (i = 0; i < (perf->state_count-1); i++) { freq = freqn; freqn = perf->states[i+1].core_frequency * 1000; if ((2 * cpu_khz) > (freqn + freq)) { @@ -673,7 +673,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) /* detect transition latency */ policy->cpuinfo.transition_latency = 0; - for (i=0; istate_count; i++) { + for (i = 0; i < perf->state_count; i++) { if ((perf->states[i].transition_latency * 1000) > policy->cpuinfo.transition_latency) policy->cpuinfo.transition_latency = @@ -682,8 +682,8 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) data->max_freq = perf->states[0].core_frequency * 1000; /* table init */ - for (i=0; istate_count; i++) { - if (i>0 && perf->states[i].core_frequency >= + for (i = 0; i < perf->state_count; i++) { + if (i > 0 && perf->states[i].core_frequency >= data->freq_table[valid_states-1].frequency / 1000) continue; -- cgit v1.2.3