Commit c788ef61 authored Jun 17, 2022 by Ian Rogers Committed by Arnaldo Carvalho de Melo Jun 19, 2022

perf metrics: Ensure at least 1 id per metric



We may have no events for a metric evaluated to a constant. In such a
case ensure a tool event is at least evaluated for metric parsing and
displaying.

Fixes: 8586d274 ("perf metrics: Don't add all tool events for sharing")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Link: https://lore.kernel.org/r/20220618013957.999321-1-irogers@google.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 37402d5d

tools/perf/util/metricgroup.c

+9 −0

Original line number	Diff line number	Diff line
		@@ -1372,6 +1372,7 @@ static int parse_ids(bool metric_no_merge, struct perf_pmu *fake_pmu,

		*out_evlist = NULL;
		if (!metric_no_merge \|\| hashmap__size(ids->ids) == 0) {
		bool added_event = false;
		int i;
		/*
		* We may fail to share events between metrics because a tool
		@@ -1393,8 +1394,16 @@ static int parse_ids(bool metric_no_merge, struct perf_pmu *fake_pmu,
		if (!tmp)
		return -ENOMEM;
		ids__insert(ids->ids, tmp);
		added_event = true;
		}
		}
		if (!added_event && hashmap__size(ids->ids) == 0) {
		char *tmp = strdup("duration_time");

		if (!tmp)
		return -ENOMEM;
		ids__insert(ids->ids, tmp);
		}
		}
		ret = metricgroup__build_event_string(&events, ids, modifier,
		has_constraint);