[PATCH] tracing: use match_string() to simplify the code

From: Yisheng Xie
Date: Thu May 17 2018 - 03:49:45 EST


match_string() returns the index of an array for a matching string,
which can be used to simplify the code.

Signed-off-by: Yisheng Xie <xieyisheng1@xxxxxxxxxx>
---
kernel/trace/trace.c | 15 +++++----------
1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 414d721..4bd653a 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4395,8 +4395,7 @@ static int trace_set_options(struct trace_array *tr, char *option)
{
char *cmp;
int neg = 0;
- int ret = -ENODEV;
- int i;
+ int ret;
size_t orig_len = strlen(option);

cmp = strstrip(option);
@@ -4408,16 +4407,12 @@ static int trace_set_options(struct trace_array *tr, char *option)

mutex_lock(&trace_types_lock);

- for (i = 0; trace_options[i]; i++) {
- if (strcmp(cmp, trace_options[i]) == 0) {
- ret = set_tracer_flag(tr, 1 << i, !neg);
- break;
- }
- }
-
+ ret = match_string(trace_options, -1, cmp);
/* If no option could be set, test the specific tracer options */
- if (!trace_options[i])
+ if (ret < 0)
ret = set_tracer_option(tr, cmp, neg);
+ else
+ ret = set_tracer_flag(tr, 1 << ret, !neg);

mutex_unlock(&trace_types_lock);

--
1.7.12.4