ftrace: Call trace_parser_clear() properly
I found a weird behavior:
# echo 'fuse:*' > set_ftrace_filter
bash: echo: write error: Invalid argument
# cat set_ftrace_filter
fuse_dev_fasync
fuse_dev_poll
fuse_copy_do
We should call trace_parser_clear() no matter ftrace_process_regex()
returns 0 or -errno, otherwise we will actually take the unaccepted
records from ftrace_regex_release().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <4B1DC4D2.3000406@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 08a3fb5..ff8aecd 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2208,10 +2208,9 @@
!trace_parser_cont(parser)) {
ret = ftrace_process_regex(parser->buffer,
parser->idx, enable);
+ trace_parser_clear(parser);
if (ret)
goto out_unlock;
-
- trace_parser_clear(parser);
}
ret = read;