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Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r--kernel/trace/ftrace.c31
1 files changed, 21 insertions, 10 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 708aea493d96..2c4eef49b1af 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1316,7 +1316,6 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable,
struct ftrace_func_entry *entry;
struct hlist_node *tn;
struct hlist_head *hhd;
- struct ftrace_hash *old_hash;
struct ftrace_hash *new_hash;
int size = src->count;
int bits = 0;
@@ -1361,9 +1360,7 @@ update:
*/
ftrace_hash_rec_disable_modify(ops, enable);
- old_hash = *dst;
rcu_assign_pointer(*dst, new_hash);
- free_ftrace_hash_rcu(old_hash);
ftrace_hash_rec_enable_modify(ops, enable);
@@ -3408,6 +3405,7 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
{
struct ftrace_func_probe *entry;
struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash;
+ struct ftrace_hash *old_hash = *orig_hash;
struct ftrace_hash *hash;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
@@ -3426,7 +3424,7 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
mutex_lock(&trace_probe_ops.func_hash->regex_lock);
- hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
+ hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash);
if (!hash) {
count = -ENOMEM;
goto out;
@@ -3485,7 +3483,9 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
} while_for_each_ftrace_rec();
ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
- if (ret < 0)
+ if (!ret)
+ free_ftrace_hash_rcu(old_hash);
+ else
count = ret;
__enable_ftrace_function_probe();
@@ -3512,6 +3512,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
struct ftrace_func_probe *entry;
struct ftrace_func_probe *p;
struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash;
+ struct ftrace_hash *old_hash = *orig_hash;
struct list_head free_list;
struct ftrace_hash *hash;
struct hlist_node *tmp;
@@ -3519,6 +3520,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
int type = MATCH_FULL;
int i, len = 0;
char *search;
+ int ret;
if (glob && (strcmp(glob, "*") == 0 || !strlen(glob)))
glob = NULL;
@@ -3577,8 +3579,11 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
* Remove after the disable is called. Otherwise, if the last
* probe is removed, a null hash means *all enabled*.
*/
- ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
+ ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
synchronize_sched();
+ if (!ret)
+ free_ftrace_hash_rcu(old_hash);
+
list_for_each_entry_safe(entry, p, &free_list, free_list) {
list_del(&entry->free_list);
ftrace_free_entry(entry);
@@ -3776,6 +3781,7 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
unsigned long ip, int remove, int reset, int enable)
{
struct ftrace_hash **orig_hash;
+ struct ftrace_hash *old_hash;
struct ftrace_hash *hash;
int ret;
@@ -3810,10 +3816,12 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
}
mutex_lock(&ftrace_lock);
+ old_hash = *orig_hash;
ret = ftrace_hash_move(ops, enable, orig_hash, hash);
- if (!ret)
+ if (!ret) {
ftrace_ops_update_code(ops);
-
+ free_ftrace_hash_rcu(old_hash);
+ }
mutex_unlock(&ftrace_lock);
out_regex_unlock:
@@ -4022,6 +4030,7 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
struct seq_file *m = (struct seq_file *)file->private_data;
struct ftrace_iterator *iter;
struct ftrace_hash **orig_hash;
+ struct ftrace_hash *old_hash;
struct trace_parser *parser;
int filter_hash;
int ret;
@@ -4051,11 +4060,13 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
orig_hash = &iter->ops->func_hash->notrace_hash;
mutex_lock(&ftrace_lock);
+ old_hash = *orig_hash;
ret = ftrace_hash_move(iter->ops, filter_hash,
orig_hash, iter->hash);
- if (!ret)
+ if (!ret) {
ftrace_ops_update_code(iter->ops);
-
+ free_ftrace_hash_rcu(old_hash);
+ }
mutex_unlock(&ftrace_lock);
}