From 606576ce816603d9fe1fb453a88bc6eea16ca709 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 6 Oct 2008 19:06:12 -0400 Subject: ftrace: rename FTRACE to FUNCTION_TRACER Due to confusion between the ftrace infrastructure and the gcc profiling tracer "ftrace", this patch renames the config options from FTRACE to FUNCTION_TRACER. The other two names that are offspring from FTRACE DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same. This patch was generated mostly by script, and partially by hand. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- include/asm-x86/ftrace.h | 4 ++-- include/linux/ftrace.h | 12 ++++++------ 2 files changed, 8 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/include/asm-x86/ftrace.h b/include/asm-x86/ftrace.h index 1bb6f9bbe1ab..233bb9b869c0 100644 --- a/include/asm-x86/ftrace.h +++ b/include/asm-x86/ftrace.h @@ -1,7 +1,7 @@ #ifndef ASM_X86__FTRACE_H #define ASM_X86__FTRACE_H -#ifdef CONFIG_FTRACE +#ifdef CONFIG_FUNCTION_TRACER #define MCOUNT_ADDR ((long)(mcount)) #define MCOUNT_INSN_SIZE 5 /* sizeof mcount call */ @@ -19,6 +19,6 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) } #endif -#endif /* CONFIG_FTRACE */ +#endif /* CONFIG_FUNCTION_TRACER */ #endif /* ASM_X86__FTRACE_H */ diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index a3d46151be19..0e9529589151 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -8,7 +8,7 @@ #include #include -#ifdef CONFIG_FTRACE +#ifdef CONFIG_FUNCTION_TRACER extern int ftrace_enabled; extern int @@ -36,12 +36,12 @@ void clear_ftrace_function(void); extern void ftrace_stub(unsigned long a0, unsigned long a1); -#else /* !CONFIG_FTRACE */ +#else /* !CONFIG_FUNCTION_TRACER */ # define register_ftrace_function(ops) do { } while (0) # define unregister_ftrace_function(ops) do { } while (0) # define clear_ftrace_function(ops) do { } while (0) static inline void ftrace_kill_atomic(void) { } -#endif /* CONFIG_FTRACE */ +#endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_DYNAMIC_FTRACE # define FTRACE_HASHBITS 10 @@ -101,7 +101,7 @@ void ftrace_kill_atomic(void); static inline void tracer_disable(void) { -#ifdef CONFIG_FTRACE +#ifdef CONFIG_FUNCTION_TRACER ftrace_enabled = 0; #endif } @@ -113,7 +113,7 @@ static inline void tracer_disable(void) */ static inline int __ftrace_enabled_save(void) { -#ifdef CONFIG_FTRACE +#ifdef CONFIG_FUNCTION_TRACER int saved_ftrace_enabled = ftrace_enabled; ftrace_enabled = 0; return saved_ftrace_enabled; @@ -124,7 +124,7 @@ static inline int __ftrace_enabled_save(void) static inline void __ftrace_enabled_restore(int enabled) { -#ifdef CONFIG_FTRACE +#ifdef CONFIG_FUNCTION_TRACER ftrace_enabled = enabled; #endif } -- cgit v1.2.3 From 593eb8a2d63e95772a5f22d746f18a997c5ee463 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 23 Oct 2008 09:32:59 -0400 Subject: ftrace: return error on failed modified text. Have the ftrace_modify_code return error values: -EFAULT on error of reading the address -EINVAL if what is read does not match what it expected -EPERM if the write fails to update after a successful match. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- arch/x86/kernel/ftrace.c | 14 +++++++------- include/linux/ftrace.h | 24 ++++++++++++++++++++++-- kernel/trace/ftrace.c | 21 +++++++++++++++------ 3 files changed, 44 insertions(+), 15 deletions(-) (limited to 'include') diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 8821ceabf51d..428291581cb2 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -62,7 +62,6 @@ ftrace_modify_code(unsigned long ip, unsigned char *old_code, unsigned char *new_code) { unsigned char replaced[MCOUNT_INSN_SIZE]; - int ret; /* * Note: Due to modules and __init, code can @@ -72,15 +71,16 @@ ftrace_modify_code(unsigned long ip, unsigned char *old_code, * No real locking needed, this code is run through * kstop_machine, or before SMP starts. */ - if (__copy_from_user_inatomic(replaced, (char __user *)ip, MCOUNT_INSN_SIZE)) - return 1; + if (__copy_from_user_inatomic(replaced, (char __user *)ip, + MCOUNT_INSN_SIZE)) + return -EFAULT; if (memcmp(replaced, old_code, MCOUNT_INSN_SIZE) != 0) - return 2; + return -EINVAL; - ret = __copy_to_user_inatomic((char __user *)ip, new_code, - MCOUNT_INSN_SIZE); - WARN_ON_ONCE(ret); + if (__copy_to_user_inatomic((char __user *)ip, new_code, + MCOUNT_INSN_SIZE)) + return -EPERM; sync_core(); diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 0e9529589151..79fa10cbdcfb 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -72,13 +72,33 @@ extern unsigned char *ftrace_nop_replace(void); extern unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr); extern int ftrace_dyn_arch_init(void *data); extern int ftrace_mcount_set(unsigned long *data); -extern int ftrace_modify_code(unsigned long ip, unsigned char *old_code, - unsigned char *new_code); extern int ftrace_update_ftrace_func(ftrace_func_t func); extern void ftrace_caller(void); extern void ftrace_call(void); extern void mcount_call(void); +/** + * ftrace_modify_code - modify code segment + * @ip: the address of the code segment + * @old_code: the contents of what is expected to be there + * @new_code: the code to patch in + * + * This is a very sensitive operation and great care needs + * to be taken by the arch. The operation should carefully + * read the location, check to see if what is read is indeed + * what we expect it to be, and then on success of the compare, + * it should write to the location. + * + * Return must be: + * 0 on success + * -EFAULT on error reading the location + * -EINVAL on a failed compare of the contents + * -EPERM on error writing to the location + * Any other value will be considered a failure. + */ +extern int ftrace_modify_code(unsigned long ip, unsigned char *old_code, + unsigned char *new_code); + extern int skip_trace(unsigned long ip); extern void ftrace_release(void *start, unsigned long size); diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 1f54a94189fe..b2de8de77356 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -596,22 +596,22 @@ ftrace_code_disable(struct dyn_ftrace *rec) { unsigned long ip; unsigned char *nop, *call; - int failed; + int ret; ip = rec->ip; nop = ftrace_nop_replace(); call = ftrace_call_replace(ip, mcount_addr); - failed = ftrace_modify_code(ip, call, nop); - if (failed) { - switch (failed) { - case 1: + ret = ftrace_modify_code(ip, call, nop); + if (ret) { + switch (ret) { + case -EFAULT: WARN_ON_ONCE(1); pr_info("ftrace faulted on modifying "); print_ip_sym(ip); break; - case 2: + case -EINVAL: WARN_ON_ONCE(1); pr_info("ftrace failed to modify "); print_ip_sym(ip); @@ -620,6 +620,15 @@ ftrace_code_disable(struct dyn_ftrace *rec) print_ip_ins(" replace: ", nop); printk(KERN_CONT "\n"); break; + case -EPERM: + WARN_ON_ONCE(1); + pr_info("ftrace faulted on writing "); + print_ip_sym(ip); + break; + default: + WARN_ON_ONCE(1); + pr_info("ftrace faulted on unknown error "); + print_ip_sym(ip); } rec->flags |= FTRACE_FL_FAILED; -- cgit v1.2.3 From 81adbdc029ecc416d56563e7f159100181dd711d Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 23 Oct 2008 09:33:02 -0400 Subject: ftrace: only have ftrace_kill atomic When an anomaly is detected, we need a way to completely disable ftrace. Right now we have two functions: ftrace_kill and ftrace_kill_atomic. The ftrace_kill tries to do it in a "nice" way by converting everything back to a nop. The "nice" way is dangerous itself, so this patch removes it and only has the "atomic" version, which is all that is needed. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- include/linux/ftrace.h | 3 +-- kernel/trace/ftrace.c | 42 ++---------------------------------------- kernel/trace/trace.c | 2 +- 3 files changed, 4 insertions(+), 43 deletions(-) (limited to 'include') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 79fa10cbdcfb..ac58e94668b7 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -40,7 +40,7 @@ extern void ftrace_stub(unsigned long a0, unsigned long a1); # define register_ftrace_function(ops) do { } while (0) # define unregister_ftrace_function(ops) do { } while (0) # define clear_ftrace_function(ops) do { } while (0) -static inline void ftrace_kill_atomic(void) { } +static inline void ftrace_kill(void) { } #endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_DYNAMIC_FTRACE @@ -117,7 +117,6 @@ static inline void ftrace_release(void *start, unsigned long size) { } /* totally disable ftrace - can not re-enable after this */ void ftrace_kill(void); -void ftrace_kill_atomic(void); static inline void tracer_disable(void) { diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index b2de8de77356..93245ae046e1 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1549,22 +1549,6 @@ int ftrace_force_update(void) return ret; } -static void ftrace_force_shutdown(void) -{ - struct task_struct *task; - int command = FTRACE_DISABLE_CALLS | FTRACE_UPDATE_TRACE_FUNC; - - mutex_lock(&ftraced_lock); - task = ftraced_task; - ftraced_task = NULL; - ftraced_suspend = -1; - ftrace_run_update_code(command); - mutex_unlock(&ftraced_lock); - - if (task) - kthread_stop(task); -} - static __init int ftrace_init_debugfs(void) { struct dentry *d_tracer; @@ -1795,17 +1779,16 @@ core_initcall(ftrace_dynamic_init); # define ftrace_shutdown() do { } while (0) # define ftrace_startup_sysctl() do { } while (0) # define ftrace_shutdown_sysctl() do { } while (0) -# define ftrace_force_shutdown() do { } while (0) #endif /* CONFIG_DYNAMIC_FTRACE */ /** - * ftrace_kill_atomic - kill ftrace from critical sections + * ftrace_kill - kill ftrace * * This function should be used by panic code. It stops ftrace * but in a not so nice way. If you need to simply kill ftrace * from a non-atomic section, use ftrace_kill. */ -void ftrace_kill_atomic(void) +void ftrace_kill(void) { ftrace_disabled = 1; ftrace_enabled = 0; @@ -1815,27 +1798,6 @@ void ftrace_kill_atomic(void) clear_ftrace_function(); } -/** - * ftrace_kill - totally shutdown ftrace - * - * This is a safety measure. If something was detected that seems - * wrong, calling this function will keep ftrace from doing - * any more modifications, and updates. - * used when something went wrong. - */ -void ftrace_kill(void) -{ - mutex_lock(&ftrace_sysctl_lock); - ftrace_disabled = 1; - ftrace_enabled = 0; - - clear_ftrace_function(); - mutex_unlock(&ftrace_sysctl_lock); - - /* Try to totally disable ftrace */ - ftrace_force_shutdown(); -} - /** * register_ftrace_function - register a function for profiling * @ops - ops structure that holds the function for profiling. diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index aeb2f2505bc5..333a5162149b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3097,7 +3097,7 @@ void ftrace_dump(void) dump_ran = 1; /* No turning back! */ - ftrace_kill_atomic(); + ftrace_kill(); for_each_tracing_cpu(cpu) { atomic_inc(&global_trace.data[cpu]->disabled); -- cgit v1.2.3 From 4d296c24326783bff1282ac72f310d8bac8df413 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 23 Oct 2008 09:33:06 -0400 Subject: ftrace: remove mcount set The arch dependent function ftrace_mcount_set was only used by the daemon start up code. This patch removes it. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- arch/arm/kernel/ftrace.c | 13 ------------- arch/powerpc/kernel/ftrace.c | 17 ----------------- arch/sparc64/kernel/ftrace.c | 18 ------------------ arch/x86/kernel/ftrace.c | 7 ------- include/linux/ftrace.h | 1 - kernel/trace/ftrace.c | 9 --------- 6 files changed, 65 deletions(-) (limited to 'include') diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c index 76d50e6091bc..6c90479e8974 100644 --- a/arch/arm/kernel/ftrace.c +++ b/arch/arm/kernel/ftrace.c @@ -95,19 +95,6 @@ int ftrace_update_ftrace_func(ftrace_func_t func) return ret; } -int ftrace_mcount_set(unsigned long *data) -{ - unsigned long pc, old; - unsigned long *addr = data; - unsigned char *new; - - pc = (unsigned long)&mcount_call; - memcpy(&old, &mcount_call, MCOUNT_INSN_SIZE); - new = ftrace_call_replace(pc, *addr); - *addr = ftrace_modify_code(pc, (unsigned char *)&old, new); - return 0; -} - /* run from kstop_machine */ int __init ftrace_dyn_arch_init(void *data) { diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c index 3855ceb937b0..6b75522e8b34 100644 --- a/arch/powerpc/kernel/ftrace.c +++ b/arch/powerpc/kernel/ftrace.c @@ -126,23 +126,6 @@ notrace int ftrace_update_ftrace_func(ftrace_func_t func) return ret; } -notrace int ftrace_mcount_set(unsigned long *data) -{ - unsigned long ip = (long)(&mcount_call); - unsigned long *addr = data; - unsigned char old[MCOUNT_INSN_SIZE], *new; - - /* - * Replace the mcount stub with a pointer to the - * ip recorder function. - */ - memcpy(old, &mcount_call, MCOUNT_INSN_SIZE); - new = ftrace_call_replace(ip, *addr); - *addr = ftrace_modify_code(ip, old, new); - - return 0; -} - int __init ftrace_dyn_arch_init(void *data) { /* This is running in kstop_machine */ diff --git a/arch/sparc64/kernel/ftrace.c b/arch/sparc64/kernel/ftrace.c index 4298d0aee713..447942041a7c 100644 --- a/arch/sparc64/kernel/ftrace.c +++ b/arch/sparc64/kernel/ftrace.c @@ -69,24 +69,6 @@ notrace int ftrace_update_ftrace_func(ftrace_func_t func) return ftrace_modify_code(ip, old, new); } -notrace int ftrace_mcount_set(unsigned long *data) -{ - unsigned long ip = (long)(&mcount_call); - unsigned long *addr = data; - unsigned char old[MCOUNT_INSN_SIZE], *new; - - /* - * Replace the mcount stub with a pointer to the - * ip recorder function. - */ - memcpy(old, &mcount_call, MCOUNT_INSN_SIZE); - new = ftrace_call_replace(ip, *addr); - *addr = ftrace_modify_code(ip, old, new); - - return 0; -} - - int __init ftrace_dyn_arch_init(void *data) { ftrace_mcount_set(data); diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index da4fb0deecf7..b399eed23538 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -103,13 +103,6 @@ notrace int ftrace_update_ftrace_func(ftrace_func_t func) return ret; } -notrace int ftrace_mcount_set(unsigned long *data) -{ - /* mcount is initialized as a nop */ - *data = 0; - return 0; -} - int __init ftrace_dyn_arch_init(void *data) { extern const unsigned char ftrace_test_p6nop[]; diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index ac58e94668b7..1c4835f86911 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -71,7 +71,6 @@ extern int ftrace_ip_converted(unsigned long ip); extern unsigned char *ftrace_nop_replace(void); extern unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr); extern int ftrace_dyn_arch_init(void *data); -extern int ftrace_mcount_set(unsigned long *data); extern int ftrace_update_ftrace_func(ftrace_func_t func); extern void ftrace_caller(void); extern void ftrace_call(void); diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index e758cab0836f..226fd9132d53 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -620,7 +620,6 @@ static int ftrace_update_code(void *ignore); static int __ftrace_modify_code(void *data) { - unsigned long addr; int *command = data; if (*command & FTRACE_ENABLE_CALLS) { @@ -639,14 +638,6 @@ static int __ftrace_modify_code(void *data) if (*command & FTRACE_UPDATE_TRACE_FUNC) ftrace_update_ftrace_func(ftrace_trace_function); - if (*command & FTRACE_ENABLE_MCOUNT) { - addr = (unsigned long)ftrace_record_ip; - ftrace_mcount_set(&addr); - } else if (*command & FTRACE_DISABLE_MCOUNT) { - addr = (unsigned long)ftrace_stub; - ftrace_mcount_set(&addr); - } - return 0; } -- cgit v1.2.3 From 08f5ac906d2c0faf96d608c54a0b03177376da8d Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 23 Oct 2008 09:33:07 -0400 Subject: ftrace: remove ftrace hash The ftrace hash was used by the ftrace_daemon code. The record ip function would place the calling address (ip) into the hash. The daemon would later read the hash and modify that code. The hash complicates the code. This patch removes it. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- include/linux/ftrace.h | 8 +- kernel/trace/ftrace.c | 243 +++++++------------------------------------------ kernel/trace/trace.c | 3 - 3 files changed, 38 insertions(+), 216 deletions(-) (limited to 'include') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 1c4835f86911..703eb53cfa2b 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -44,8 +44,6 @@ static inline void ftrace_kill(void) { } #endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_DYNAMIC_FTRACE -# define FTRACE_HASHBITS 10 -# define FTRACE_HASHSIZE (1< #include #include -#include #include #include @@ -189,9 +188,7 @@ static int ftrace_filtered; static int tracing_on; static int frozen_record_count; -static struct hlist_head ftrace_hash[FTRACE_HASHSIZE]; - -static DEFINE_PER_CPU(int, ftrace_shutdown_disable_cpu); +static LIST_HEAD(ftrace_new_addrs); static DEFINE_MUTEX(ftrace_regex_lock); @@ -210,8 +207,6 @@ struct ftrace_page { static struct ftrace_page *ftrace_pages_start; static struct ftrace_page *ftrace_pages; -static int ftrace_record_suspend; - static struct dyn_ftrace *ftrace_free_records; @@ -242,72 +237,6 @@ static inline int record_frozen(struct dyn_ftrace *rec) # define record_frozen(rec) ({ 0; }) #endif /* CONFIG_KPROBES */ -int skip_trace(unsigned long ip) -{ - unsigned long fl; - struct dyn_ftrace *rec; - struct hlist_node *t; - struct hlist_head *head; - - if (frozen_record_count == 0) - return 0; - - head = &ftrace_hash[hash_long(ip, FTRACE_HASHBITS)]; - hlist_for_each_entry_rcu(rec, t, head, node) { - if (rec->ip == ip) { - if (record_frozen(rec)) { - if (rec->flags & FTRACE_FL_FAILED) - return 1; - - if (!(rec->flags & FTRACE_FL_CONVERTED)) - return 1; - - if (!tracing_on || !ftrace_enabled) - return 1; - - if (ftrace_filtered) { - fl = rec->flags & (FTRACE_FL_FILTER | - FTRACE_FL_NOTRACE); - if (!fl || (fl & FTRACE_FL_NOTRACE)) - return 1; - } - } - break; - } - } - - return 0; -} - -static inline int -ftrace_ip_in_hash(unsigned long ip, unsigned long key) -{ - struct dyn_ftrace *p; - struct hlist_node *t; - int found = 0; - - hlist_for_each_entry_rcu(p, t, &ftrace_hash[key], node) { - if (p->ip == ip) { - found = 1; - break; - } - } - - return found; -} - -static inline void -ftrace_add_hash(struct dyn_ftrace *node, unsigned long key) -{ - hlist_add_head_rcu(&node->node, &ftrace_hash[key]); -} - -/* called from kstop_machine */ -static inline void ftrace_del_hash(struct dyn_ftrace *node) -{ - hlist_del(&node->node); -} - static void ftrace_free_rec(struct dyn_ftrace *rec) { rec->ip = (unsigned long)ftrace_free_records; @@ -362,69 +291,36 @@ static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) } if (ftrace_pages->index == ENTRIES_PER_PAGE) { - if (!ftrace_pages->next) - return NULL; + if (!ftrace_pages->next) { + /* allocate another page */ + ftrace_pages->next = + (void *)get_zeroed_page(GFP_KERNEL); + if (!ftrace_pages->next) + return NULL; + } ftrace_pages = ftrace_pages->next; } return &ftrace_pages->records[ftrace_pages->index++]; } -static void +static struct dyn_ftrace * ftrace_record_ip(unsigned long ip) { - struct dyn_ftrace *node; - unsigned long key; - int resched; - int cpu; + struct dyn_ftrace *rec; if (!ftrace_enabled || ftrace_disabled) - return; - - resched = need_resched(); - preempt_disable_notrace(); - - /* - * We simply need to protect against recursion. - * Use the the raw version of smp_processor_id and not - * __get_cpu_var which can call debug hooks that can - * cause a recursive crash here. - */ - cpu = raw_smp_processor_id(); - per_cpu(ftrace_shutdown_disable_cpu, cpu)++; - if (per_cpu(ftrace_shutdown_disable_cpu, cpu) != 1) - goto out; - - if (unlikely(ftrace_record_suspend)) - goto out; - - key = hash_long(ip, FTRACE_HASHBITS); - - FTRACE_WARN_ON_ONCE(key >= FTRACE_HASHSIZE); - - if (ftrace_ip_in_hash(ip, key)) - goto out; - - /* This ip may have hit the hash before the lock */ - if (ftrace_ip_in_hash(ip, key)) - goto out; - - node = ftrace_alloc_dyn_node(ip); - if (!node) - goto out; + return NULL; - node->ip = ip; + rec = ftrace_alloc_dyn_node(ip); + if (!rec) + return NULL; - ftrace_add_hash(node, key); + rec->ip = ip; - out: - per_cpu(ftrace_shutdown_disable_cpu, cpu)--; + list_add(&rec->list, &ftrace_new_addrs); - /* prevent recursion with scheduler */ - if (resched) - preempt_enable_no_resched_notrace(); - else - preempt_enable_notrace(); + return rec; } #define FTRACE_ADDR ((long)(ftrace_caller)) @@ -543,7 +439,6 @@ static void ftrace_replace_code(int enable) rec->flags |= FTRACE_FL_FAILED; if ((system_state == SYSTEM_BOOTING) || !core_kernel_text(rec->ip)) { - ftrace_del_hash(rec); ftrace_free_rec(rec); } } @@ -551,15 +446,6 @@ static void ftrace_replace_code(int enable) } } -static void ftrace_shutdown_replenish(void) -{ - if (ftrace_pages->next) - return; - - /* allocate another page */ - ftrace_pages->next = (void *)get_zeroed_page(GFP_KERNEL); -} - static void print_ip_ins(const char *fmt, unsigned char *p) { int i; @@ -616,18 +502,11 @@ ftrace_code_disable(struct dyn_ftrace *rec) return 1; } -static int ftrace_update_code(void *ignore); - static int __ftrace_modify_code(void *data) { int *command = data; if (*command & FTRACE_ENABLE_CALLS) { - /* - * Update any recorded ips now that we have the - * machine stopped - */ - ftrace_update_code(NULL); ftrace_replace_code(1); tracing_on = 1; } else if (*command & FTRACE_DISABLE_CALLS) { @@ -738,84 +617,34 @@ static cycle_t ftrace_update_time; static unsigned long ftrace_update_cnt; unsigned long ftrace_update_tot_cnt; -static int ftrace_update_code(void *ignore) +static int ftrace_update_code(void) { - int i, save_ftrace_enabled; + struct dyn_ftrace *p, *t; cycle_t start, stop; - struct dyn_ftrace *p; - struct hlist_node *t, *n; - struct hlist_head *head, temp_list; - - /* Don't be recording funcs now */ - ftrace_record_suspend++; - save_ftrace_enabled = ftrace_enabled; - ftrace_enabled = 0; start = ftrace_now(raw_smp_processor_id()); ftrace_update_cnt = 0; - /* No locks needed, the machine is stopped! */ - for (i = 0; i < FTRACE_HASHSIZE; i++) { - INIT_HLIST_HEAD(&temp_list); - head = &ftrace_hash[i]; + list_for_each_entry_safe(p, t, &ftrace_new_addrs, list) { - /* all CPUS are stopped, we are safe to modify code */ - hlist_for_each_entry_safe(p, t, n, head, node) { - /* Skip over failed records which have not been - * freed. */ - if (p->flags & FTRACE_FL_FAILED) - continue; + /* If something went wrong, bail without enabling anything */ + if (unlikely(ftrace_disabled)) + return -1; - /* Unconverted records are always at the head of the - * hash bucket. Once we encounter a converted record, - * simply skip over to the next bucket. Saves ftraced - * some processor cycles (ftrace does its bid for - * global warming :-p ). */ - if (p->flags & (FTRACE_FL_CONVERTED)) - break; + list_del_init(&p->list); - /* Ignore updates to this record's mcount site. - * Reintroduce this record at the head of this - * bucket to attempt to "convert" it again if - * the kprobe on it is unregistered before the - * next run. */ - if (get_kprobe((void *)p->ip)) { - ftrace_del_hash(p); - INIT_HLIST_NODE(&p->node); - hlist_add_head(&p->node, &temp_list); - freeze_record(p); - continue; - } else { - unfreeze_record(p); - } - - /* convert record (i.e, patch mcount-call with NOP) */ - if (ftrace_code_disable(p)) { - p->flags |= FTRACE_FL_CONVERTED; - ftrace_update_cnt++; - } else { - if ((system_state == SYSTEM_BOOTING) || - !core_kernel_text(p->ip)) { - ftrace_del_hash(p); - ftrace_free_rec(p); - } - } - } - - hlist_for_each_entry_safe(p, t, n, &temp_list, node) { - hlist_del(&p->node); - INIT_HLIST_NODE(&p->node); - hlist_add_head(&p->node, head); - } + /* convert record (i.e, patch mcount-call with NOP) */ + if (ftrace_code_disable(p)) { + p->flags |= FTRACE_FL_CONVERTED; + ftrace_update_cnt++; + } else + ftrace_free_rec(p); } stop = ftrace_now(raw_smp_processor_id()); ftrace_update_time = stop - start; ftrace_update_tot_cnt += ftrace_update_cnt; - ftrace_enabled = save_ftrace_enabled; - ftrace_record_suspend--; - return 0; } @@ -847,7 +676,7 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) pg = ftrace_pages = ftrace_pages_start; cnt = num_to_init / ENTRIES_PER_PAGE; - pr_info("ftrace: allocating %ld hash entries in %d pages\n", + pr_info("ftrace: allocating %ld entries in %d pages\n", num_to_init, cnt); for (i = 0; i < cnt; i++) { @@ -1451,20 +1280,18 @@ static int ftrace_convert_nops(unsigned long *start, unsigned long addr; unsigned long flags; + mutex_lock(&ftrace_start_lock); p = start; while (p < end) { addr = ftrace_call_adjust(*p++); - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); ftrace_record_ip(addr); - spin_unlock(&ftrace_lock); - ftrace_shutdown_replenish(); } - /* p is ignored */ + /* disable interrupts to prevent kstop machine */ local_irq_save(flags); - ftrace_update_code(p); + ftrace_update_code(); local_irq_restore(flags); + mutex_unlock(&ftrace_start_lock); return 0; } diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 333a5162149b..06951e229443 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -865,9 +865,6 @@ function_trace_call(unsigned long ip, unsigned long parent_ip) if (unlikely(!ftrace_function_enabled)) return; - if (skip_trace(ip)) - return; - pc = preempt_count(); resched = need_resched(); preempt_disable_notrace(); -- cgit v1.2.3 From 5209f08dc8e5f520ca81b87fa9a7142f58a109f4 Mon Sep 17 00:00:00 2001 From: Jonas Bonn Date: Sat, 25 Oct 2008 11:49:20 +0200 Subject: asm-generic: define DIE_OOPS in asm-generic Impact: build fix DIE_OOPS is now used in the generic trace handling code so it needs to be defined for all architectures. Define it in asm-generic so that it's available to all by default and doesn't cause build errors for architectures that rely on the generic implementation. Signed-off-by: Jonas Bonn Acked-by: Steven Rostedt Signed-off-by: Ingo Molnar --- include/asm-generic/kdebug.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/asm-generic/kdebug.h b/include/asm-generic/kdebug.h index 2b799c90b2d4..11e57b6a85fc 100644 --- a/include/asm-generic/kdebug.h +++ b/include/asm-generic/kdebug.h @@ -3,6 +3,7 @@ enum die_val { DIE_UNUSED, + DIE_OOPS=1 }; #endif /* _ASM_GENERIC_KDEBUG_H */ -- cgit v1.2.3