diff options
| -rw-r--r-- | include/linux/ftrace.h | 4 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 73 |
2 files changed, 56 insertions, 21 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index f83e17a40e8b..99d0fbcbaf79 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -90,6 +90,8 @@ typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, * not set this, then the ftrace infrastructure will add recursion * protection for the caller. * STUB - The ftrace_ops is just a place holder. + * INITIALIZED - The ftrace_ops has already been initialized (first use time + * register_ftrace_function() is called, it will initialized the ops) */ enum { FTRACE_OPS_FL_ENABLED = 1 << 0, @@ -100,6 +102,7 @@ enum { FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 5, FTRACE_OPS_FL_RECURSION_SAFE = 1 << 6, FTRACE_OPS_FL_STUB = 1 << 7, + FTRACE_OPS_FL_INITIALIZED = 1 << 8, }; struct ftrace_ops { @@ -110,6 +113,7 @@ struct ftrace_ops { #ifdef CONFIG_DYNAMIC_FTRACE struct ftrace_hash *notrace_hash; struct ftrace_hash *filter_hash; + struct mutex regex_lock; #endif }; diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index d85a0ad81a67..827f2fe7bc3f 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -64,6 +64,13 @@ #define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_CONTROL) +#ifdef CONFIG_DYNAMIC_FTRACE +#define INIT_REGEX_LOCK(opsname) \ + .regex_lock = __MUTEX_INITIALIZER(opsname.regex_lock), +#else +#define INIT_REGEX_LOCK(opsname) +#endif + static struct ftrace_ops ftrace_list_end __read_mostly = { .func = ftrace_stub, .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, @@ -131,6 +138,16 @@ static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); while (likely(op = rcu_dereference_raw((op)->next)) && \ unlikely((op) != &ftrace_list_end)) +static inline void ftrace_ops_init(struct ftrace_ops *ops) +{ +#ifdef CONFIG_DYNAMIC_FTRACE + if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { + mutex_init(&ops->regex_lock); + ops->flags |= FTRACE_OPS_FL_INITIALIZED; + } +#endif +} + /** * ftrace_nr_registered_ops - return number of ops registered * @@ -907,7 +924,8 @@ static void unregister_ftrace_profiler(void) #else static struct ftrace_ops ftrace_profile_ops __read_mostly = { .func = function_profile_call, - .flags = FTRACE_OPS_FL_RECURSION_SAFE, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(ftrace_profile_ops) }; static int register_ftrace_profiler(void) @@ -1103,11 +1121,10 @@ static struct ftrace_ops global_ops = { .func = ftrace_stub, .notrace_hash = EMPTY_HASH, .filter_hash = EMPTY_HASH, - .flags = FTRACE_OPS_FL_RECURSION_SAFE, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(global_ops) }; -static DEFINE_MUTEX(ftrace_regex_lock); - struct ftrace_page { struct ftrace_page *next; struct dyn_ftrace *records; @@ -1247,6 +1264,7 @@ static void free_ftrace_hash_rcu(struct ftrace_hash *hash) void ftrace_free_filter(struct ftrace_ops *ops) { + ftrace_ops_init(ops); free_ftrace_hash(ops->filter_hash); free_ftrace_hash(ops->notrace_hash); } @@ -2624,6 +2642,8 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag, struct ftrace_hash *hash; int ret = 0; + ftrace_ops_init(ops); + if (unlikely(ftrace_disabled)) return -ENODEV; @@ -2656,7 +2676,7 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag, } } - mutex_lock(&ftrace_regex_lock); + mutex_lock(&ops->regex_lock); if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) @@ -2677,7 +2697,7 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag, } } else file->private_data = iter; - mutex_unlock(&ftrace_regex_lock); + mutex_unlock(&ops->regex_lock); return ret; } @@ -2910,6 +2930,8 @@ static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, static struct ftrace_ops trace_probe_ops __read_mostly = { .func = function_trace_probe_call, + .flags = FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(trace_probe_ops) }; static int ftrace_probe_registered; @@ -3256,18 +3278,18 @@ ftrace_regex_write(struct file *file, const char __user *ubuf, if (!cnt) return 0; - mutex_lock(&ftrace_regex_lock); - - ret = -ENODEV; - if (unlikely(ftrace_disabled)) - goto out_unlock; - if (file->f_mode & FMODE_READ) { struct seq_file *m = file->private_data; iter = m->private; } else iter = file->private_data; + mutex_lock(&iter->ops->regex_lock); + + ret = -ENODEV; + if (unlikely(ftrace_disabled)) + goto out_unlock; + parser = &iter->parser; read = trace_get_user(parser, ubuf, cnt, ppos); @@ -3282,7 +3304,7 @@ ftrace_regex_write(struct file *file, const char __user *ubuf, ret = read; out_unlock: - mutex_unlock(&ftrace_regex_lock); + mutex_unlock(&iter->ops->regex_lock); return ret; } @@ -3344,7 +3366,7 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, if (!hash) return -ENOMEM; - mutex_lock(&ftrace_regex_lock); + mutex_lock(&ops->regex_lock); if (reset) ftrace_filter_reset(hash); if (buf && !ftrace_match_records(hash, buf, len)) { @@ -3366,7 +3388,7 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, mutex_unlock(&ftrace_lock); out_regex_unlock: - mutex_unlock(&ftrace_regex_lock); + mutex_unlock(&ops->regex_lock); free_ftrace_hash(hash); return ret; @@ -3392,6 +3414,7 @@ ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, int remove, int reset) { + ftrace_ops_init(ops); return ftrace_set_addr(ops, ip, remove, reset, 1); } EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); @@ -3416,6 +3439,7 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, int len, int reset) { + ftrace_ops_init(ops); return ftrace_set_regex(ops, buf, len, reset, 1); } EXPORT_SYMBOL_GPL(ftrace_set_filter); @@ -3434,6 +3458,7 @@ EXPORT_SYMBOL_GPL(ftrace_set_filter); int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, int len, int reset) { + ftrace_ops_init(ops); return ftrace_set_regex(ops, buf, len, reset, 0); } EXPORT_SYMBOL_GPL(ftrace_set_notrace); @@ -3524,6 +3549,8 @@ ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) { char *func; + ftrace_ops_init(ops); + while (buf) { func = strsep(&buf, ","); ftrace_set_regex(ops, func, strlen(func), 0, enable); @@ -3551,14 +3578,14 @@ int ftrace_regex_release(struct inode *inode, struct file *file) int filter_hash; int ret; - mutex_lock(&ftrace_regex_lock); if (file->f_mode & FMODE_READ) { iter = m->private; - seq_release(inode, file); } else iter = file->private_data; + mutex_lock(&iter->ops->regex_lock); + parser = &iter->parser; if (trace_parser_loaded(parser)) { parser->buffer[parser->idx] = 0; @@ -3587,7 +3614,7 @@ int ftrace_regex_release(struct inode *inode, struct file *file) free_ftrace_hash(iter->hash); kfree(iter); - mutex_unlock(&ftrace_regex_lock); + mutex_unlock(&iter->ops->regex_lock); return 0; } @@ -4126,7 +4153,8 @@ void __init ftrace_init(void) static struct ftrace_ops global_ops = { .func = ftrace_stub, - .flags = FTRACE_OPS_FL_RECURSION_SAFE, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(global_ops) }; static int __init ftrace_nodyn_init(void) @@ -4180,8 +4208,9 @@ ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip, } static struct ftrace_ops control_ops = { - .func = ftrace_ops_control_func, - .flags = FTRACE_OPS_FL_RECURSION_SAFE, + .func = ftrace_ops_control_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(control_ops) }; static inline void @@ -4539,6 +4568,8 @@ int register_ftrace_function(struct ftrace_ops *ops) { int ret = -1; + ftrace_ops_init(ops); + mutex_lock(&ftrace_lock); ret = __register_ftrace_function(ops); |