tracing: Change `if (strlen(glob))` to `if (glob[0])`

No need to traverse to the end of string. If the first byte is not a NUL
char, it's guaranteed `if (strlen(glob))` is true.

Link: https://lkml.kernel.org/r/20220417185630.199062-3-ammarfaizi2@gnuweeb.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: GNU/Weeb Mailing List <gwml@vger.gnuweeb.org>
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 80c25be..fe10179 100644 (file)
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -6217,7 +6217,7 @@ static int event_hist_trigger_parse(struct event_command *cmd_ops,
        if (WARN_ON(!glob))
                return -EINVAL;
 
-       if (strlen(glob)) {
+       if (glob[0]) {
                hist_err_clear();
                last_cmd_set(file, param_and_filter);
        }