summaryrefslogtreecommitdiffstats
path: root/kernel/trace/ftrace.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r--kernel/trace/ftrace.c126
1 files changed, 84 insertions, 42 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8a5c017..b549b0f 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);
}
@@ -2441,7 +2459,7 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
!ftrace_lookup_ip(ops->notrace_hash, rec->ip)) ||
((iter->flags & FTRACE_ITER_ENABLED) &&
- !(rec->flags & ~FTRACE_FL_MASK))) {
+ !(rec->flags & FTRACE_FL_ENABLED))) {
rec = NULL;
goto retry;
@@ -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;
@@ -2636,28 +2656,26 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
return -ENOMEM;
}
+ iter->ops = ops;
+ iter->flags = flag;
+
+ mutex_lock(&ops->regex_lock);
+
if (flag & FTRACE_ITER_NOTRACE)
hash = ops->notrace_hash;
else
hash = ops->filter_hash;
- iter->ops = ops;
- iter->flags = flag;
-
if (file->f_mode & FMODE_WRITE) {
- mutex_lock(&ftrace_lock);
iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash);
- mutex_unlock(&ftrace_lock);
-
if (!iter->hash) {
trace_parser_put(&iter->parser);
kfree(iter);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto out_unlock;
}
}
- mutex_lock(&ftrace_regex_lock);
-
if ((file->f_mode & FMODE_WRITE) &&
(file->f_flags & O_TRUNC))
ftrace_filter_reset(iter->hash);
@@ -2677,7 +2695,9 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
}
} else
file->private_data = iter;
- mutex_unlock(&ftrace_regex_lock);
+
+ out_unlock:
+ 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;
@@ -2919,8 +2941,12 @@ static void __enable_ftrace_function_probe(void)
int ret;
int i;
- if (ftrace_probe_registered)
+ if (ftrace_probe_registered) {
+ /* still need to update the function call sites */
+ if (ftrace_enabled)
+ ftrace_run_update_code(FTRACE_UPDATE_CALLS);
return;
+ }
for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
struct hlist_head *hhd = &ftrace_func_hash[i];
@@ -2990,19 +3016,21 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
if (WARN_ON(not))
return -EINVAL;
- mutex_lock(&ftrace_lock);
+ mutex_lock(&trace_probe_ops.regex_lock);
hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
if (!hash) {
count = -ENOMEM;
- goto out_unlock;
+ goto out;
}
if (unlikely(ftrace_disabled)) {
count = -ENODEV;
- goto out_unlock;
+ goto out;
}
+ mutex_lock(&ftrace_lock);
+
do_for_each_ftrace_rec(pg, rec) {
if (!ftrace_match_record(rec, NULL, search, len, type))
@@ -3056,6 +3084,8 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
out_unlock:
mutex_unlock(&ftrace_lock);
+ out:
+ mutex_unlock(&trace_probe_ops.regex_lock);
free_ftrace_hash(hash);
return count;
@@ -3095,7 +3125,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
return;
}
- mutex_lock(&ftrace_lock);
+ mutex_lock(&trace_probe_ops.regex_lock);
hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
if (!hash)
@@ -3133,6 +3163,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
list_add(&entry->free_list, &free_list);
}
}
+ mutex_lock(&ftrace_lock);
__disable_ftrace_function_probe();
/*
* Remove after the disable is called. Otherwise, if the last
@@ -3144,9 +3175,10 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
list_del(&entry->free_list);
ftrace_free_entry(entry);
}
+ mutex_unlock(&ftrace_lock);
out_unlock:
- mutex_unlock(&ftrace_lock);
+ mutex_unlock(&trace_probe_ops.regex_lock);
free_ftrace_hash(hash);
}
@@ -3256,18 +3288,17 @@ 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;
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ /* iter->hash is a local copy, so we don't need regex_lock */
+
parser = &iter->parser;
read = trace_get_user(parser, ubuf, cnt, ppos);
@@ -3276,14 +3307,12 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
ret = ftrace_process_regex(iter->hash, parser->buffer,
parser->idx, enable);
trace_parser_clear(parser);
- if (ret)
- goto out_unlock;
+ if (ret < 0)
+ goto out;
}
ret = read;
-out_unlock:
- mutex_unlock(&ftrace_regex_lock);
-
+ out:
return ret;
}
@@ -3335,16 +3364,19 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
if (unlikely(ftrace_disabled))
return -ENODEV;
+ mutex_lock(&ops->regex_lock);
+
if (enable)
orig_hash = &ops->filter_hash;
else
orig_hash = &ops->notrace_hash;
hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
- if (!hash)
- return -ENOMEM;
+ if (!hash) {
+ ret = -ENOMEM;
+ goto out_regex_unlock;
+ }
- mutex_lock(&ftrace_regex_lock);
if (reset)
ftrace_filter_reset(hash);
if (buf && !ftrace_match_records(hash, buf, len)) {
@@ -3366,7 +3398,7 @@ 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 +3424,7 @@ 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 +3449,7 @@ 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 +3468,7 @@ 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 +3559,8 @@ 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);
@@ -3551,10 +3588,8 @@ 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;
@@ -3567,6 +3602,8 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
trace_parser_put(parser);
+ mutex_lock(&iter->ops->regex_lock);
+
if (file->f_mode & FMODE_WRITE) {
filter_hash = !!(iter->flags & FTRACE_ITER_FILTER);
@@ -3584,10 +3621,11 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
mutex_unlock(&ftrace_lock);
}
+
+ mutex_unlock(&iter->ops->regex_lock);
free_ftrace_hash(iter->hash);
kfree(iter);
- mutex_unlock(&ftrace_regex_lock);
return 0;
}
@@ -4126,7 +4164,8 @@ 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 +4219,9 @@ 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 +4579,8 @@ int register_ftrace_function(struct ftrace_ops *ops)
{
int ret = -1;
+ ftrace_ops_init(ops);
+
mutex_lock(&ftrace_lock);
ret = __register_ftrace_function(ops);
OpenPOWER on IntegriCloud