perf metric: Don't remove scale from counts

captain5050 · namhyung · commit 6d6be5eb45b4 · 2024-02-13T13:48:09.000-08:00
Counts were switched from the scaled saved value form to the aggregated count to avoid double accounting. When this happened the removing of scaling for a count should have been removed, however, it wasn't and this wasn't observed as it normally doesn't matter because a counter's scale is 1. A problem was observed with RAPL events that are scaled. Fixes: 37cc8ad ("perf metric: Directly use counts rather than saved_value") Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: James Clark <james.clark@arm.com> Cc: Kaige Ye <ye@kaige.org> Cc: John Garry <john.g.garry@oracle.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240209204947.3873294-5-irogers@google.com
diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
@@ -414,12 +414,7 @@ static int prepare_metric(struct evsel **metric_events,
 				val = NAN;
 				source_count = 0;
 			} else {
-				/*
-				 * If an event was scaled during stat gathering,
-				 * reverse the scale before computing the
-				 * metric.
-				 */
-				val = aggr->counts.val * (1.0 / metric_events[i]->scale);
+				val = aggr->counts.val;
 				source_count = evsel__source_count(metric_events[i]);
 			}
 		}

Original file line number	Diff line number	Diff line change
`@@ -414,12 +414,7 @@ static int prepare_metric(struct evsel **metric_events,`
`414`	`414`	`val = NAN;`
`415`	`415`	`source_count = 0;`
`416`	`416`	`} else {`
`417`		`- /*`
`418`		`- * If an event was scaled during stat gathering,`
`419`		`- * reverse the scale before computing the`
`420`		`- * metric.`
`421`		`- */`
`422`		`- val = aggr->counts.val * (1.0 / metric_events[i]->scale);`
	`417`	`+ val = aggr->counts.val;`
`423`	`418`	`source_count = evsel__source_count(metric_events[i]);`
`424`	`419`	`}`
`425`	`420`	`}`