perf sched latency: Fix subcommand matching error

perf sched latency use strncmp to match subcommands which matching does not
meet expectation.

Before:

  # perf sched lat1234 >/dev/null
  # echo $?
  0
  #

Solution: Use strstarts to match subcommand.

After:

   # perf sched lat1234

   Usage: perf sched [<options>] {record|latency|map|replay|script|timehist}

      -D, --dump-raw-trace  dump raw trace in ASCII
      -f, --force           don't complain, do it
      -i, --input <file>    input file name
      -v, --verbose         be more verbose (show symbol address, etc)

  # echo $?
  129
  #
  # perf sched lat >/dev/null
  # echo $?
  0
  #

Signed-off-by: Yang Jihong <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

1 files changed, 1 insertions, 1 deletions

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index 646bd938927a..2f6cd1b8b662 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -3563,7 +3563,7 @@ int cmd_sched(int argc, const char **argv)
 
 	if (strlen(argv[0]) > 2 && strstarts("record", argv[0])) {
 		return __cmd_record(argc, argv);
-	} else if (!strncmp(argv[0], "lat", 3)) {
+	} else if (strlen(argv[0]) > 2 && strstarts("latency", argv[0])) {
 		sched.tp_handler = &lat_ops;
 		if (argc > 1) {
 			argc = parse_options(argc, argv, latency_options, latency_usage, 0);