]> git.ipfire.org Git - thirdparty/kernel/stable.git/commitdiff
perf stat: Stop repeating when ref_perf_stat() returns -1
authorLevi Yun <yeoreum.yun@arm.com>
Wed, 25 Sep 2024 13:20:22 +0000 (14:20 +0100)
committerNamhyung Kim <namhyung@kernel.org>
Wed, 25 Sep 2024 22:58:42 +0000 (15:58 -0700)
Exit when run_perf_stat() returns an error to avoid continuously
repeating the same error message. It's not expected that COUNTER_FATAL
or internal errors are recoverable so there's no point in retrying.

This fixes the following flood of error messages for permission issues,
for example when perf_event_paranoid==3:
  perf stat -r 1044 -- false

  Error:
  Access to performance monitoring and observability operations is limited.
  ...
  Error:
  Access to performance monitoring and observability operations is limited.
  ...
  (repeating for 1044 times).

Signed-off-by: Levi Yun <yeoreum.yun@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Cc: nd@arm.com
Cc: howardchu95@gmail.com
Link: https://lore.kernel.org/r/20240925132022.2650180-3-yeoreum.yun@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
tools/perf/builtin-stat.c

index 2c46bdbd9914d0a20a2e68e5c54adadbc7cfbd46..6cad3435b19847b03363e9423dcf81a8f486216d 100644 (file)
@@ -968,6 +968,14 @@ err_out:
        return err;
 }
 
+/*
+ * Returns -1 for fatal errors which signifies to not continue
+ * when in repeat mode.
+ *
+ * Returns < -1 error codes when stat record is used. These
+ * result in the stat information being displayed, but writing
+ * to the file fails and is non fatal.
+ */
 static int run_perf_stat(int argc, const char **argv, int run_idx)
 {
        int ret;
@@ -2899,7 +2907,10 @@ int cmd_stat(int argc, const char **argv)
                        evlist__reset_prev_raw_counts(evsel_list);
 
                status = run_perf_stat(argc, argv, run_idx);
-               if (forever && status != -1 && !interval) {
+               if (status == -1)
+                       break;
+
+               if (forever && !interval) {
                        print_counters(NULL, argc, argv);
                        perf_stat__reset_stats();
                }