Patch "perf stat: Avoid merging/aggregating metric counts twice" has been added to the 6.2-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    perf stat: Avoid merging/aggregating metric counts twice

to the 6.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     perf-stat-avoid-merging-aggregating-metric-counts-tw.patch
and it can be found in the queue-6.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 3aaa350ca1f93282545e116db397adea7992781c
Author: Ian Rogers <irogers@xxxxxxxxxx>
Date:   Wed Feb 8 22:44:47 2023 -0800

    perf stat: Avoid merging/aggregating metric counts twice
    
    [ Upstream commit 37f322cd58d81a9d46456531281c908de9ef6e42 ]
    
    The added perf_stat_merge_counters combines uncore counters. When
    metrics are enabled, the counts are merged into a metric_leader via the
    stat-shadow saved_value logic. As the leader now is passed an aggregated
    count, it leads to all counters being added together twice and counts
    appearing approximately doubled in metrics.
    
    This change disables the saved_value merging of counts for evsels that
    are merged. It is recommended that later changes remove the saved_value
    entirely as the two layers of aggregation in the code is confusing.
    
    Fixes: 942c5593393d9418 ("perf stat: Add perf_stat_merge_counters()")
    Reported-by: Perry Taylor <perry.taylor@xxxxxxxxx>
    Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
    Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
    Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
    Cc: Eduard Zingerman <eddyz87@xxxxxxxxx>
    Cc: Florian Fischer <florian.fischer@muhq.space>
    Cc: Ingo Molnar <mingo@xxxxxxxxxx>
    Cc: James Clark <james.clark@xxxxxxx>
    Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
    Cc: Mark Rutland <mark.rutland@xxxxxxx>
    Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
    Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
    Cc: Stephane Eranian <eranian@xxxxxxxxxx>
    Cc: Xing Zhengjun <zhengjun.xing@xxxxxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20230209064447.83733-1-irogers@xxxxxxxxxx
    Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
index cadb2df23c878..4cd05d9205e3b 100644
--- a/tools/perf/util/stat-shadow.c
+++ b/tools/perf/util/stat-shadow.c
@@ -311,7 +311,7 @@ void perf_stat__update_shadow_stats(struct evsel *counter, u64 count,
 		update_stats(&v->stats, count);
 		if (counter->metric_leader)
 			v->metric_total += count;
-	} else if (counter->metric_leader) {
+	} else if (counter->metric_leader && !counter->merged_stat) {
 		v = saved_value_lookup(counter->metric_leader,
 				       map_idx, true, STAT_NONE, 0, st, rsd.cgrp);
 		v->metric_total += count;