From: Steven Rostedt <[email protected]> The ftrace_lock is taken for most of the ftrace_graph_set_hash() function throughout the end. Use guard to take the ftrace_lock to simplify the exit paths.
Signed-off-by: Steven Rostedt (Google) <[email protected]> --- kernel/trace/ftrace.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index c0fabd7da5b2..b4ef469f4fd2 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6816,12 +6816,10 @@ ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) func_g.len = strlen(func_g.search); - mutex_lock(&ftrace_lock); + guard(mutex)(&ftrace_lock); - if (unlikely(ftrace_disabled)) { - mutex_unlock(&ftrace_lock); + if (unlikely(ftrace_disabled)) return -ENODEV; - } do_for_each_ftrace_rec(pg, rec) { @@ -6837,7 +6835,7 @@ ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) if (entry) continue; if (add_hash_entry(hash, rec->ip) == NULL) - goto out; + return 0; } else { if (entry) { free_hash_entry(hash, entry); @@ -6846,13 +6844,8 @@ ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) } } } while_for_each_ftrace_rec(); -out: - mutex_unlock(&ftrace_lock); - if (fail) - return -EINVAL; - - return 0; + return fail ? -EINVAL : 0; } static ssize_t -- 2.45.2
