[PATCH 5.15 133/136] perf stat: Clear evsel->reset_group for each stat run

From: Greg Kroah-Hartman
Date: Mon Aug 29 2022 - 07:23:14 EST


From: Ian Rogers <irogers@xxxxxxxxxx>

commit bf515f024e4c0ca46a1b08c4f31860c01781d8a5 upstream.

If a weak group is broken then the reset_group flag remains set for
the next run. Having reset_group set means the counter isn't created
and ultimately a segfault.

A simple reproduction of this is:

# perf stat -r2 -e '{cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles}:W

which will be added as a test in the next patch.

Fixes: 4804e0111662d7d8 ("perf stat: Use affinity for opening events")
Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Tested-by: Xing Zhengjun <zhengjun.xing@xxxxxxxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220822213352.75721-1-irogers@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/perf/builtin-stat.c | 1 +
1 file changed, 1 insertion(+)

--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -807,6 +807,7 @@ static int __run_perf_stat(int argc, con
return -1;

evlist__for_each_entry(evsel_list, counter) {
+ counter->reset_group = false;
if (bpf_counter__load(counter, &target))
return -1;
if (!evsel__is_bpf(counter))