[PATCH v3 16/27] perf stat: Warn group events from different hybrid PMU

From: Jin Yao
Date: Mon Mar 29 2021 - 03:03:19 EST


If a group has events which are from different hybrid PMUs,
shows a warning:

"WARNING: events in group from different hybrid PMUs!"

This is to remind the user not to put the core event and atom
event into one group.

Next, just disable grouping.

# perf stat -e "{cpu_core/cycles/,cpu_atom/cycles/}" -a -- sleep 1
WARNING: events in group from different hybrid PMUs!
WARNING: grouped events cpus do not match, disabling group:
anon group { cpu_core/cycles/, cpu_atom/cycles/ }

Performance counter stats for 'system wide':

5,438,125 cpu_core/cycles/
3,914,586 cpu_atom/cycles/

1.004250966 seconds time elapsed

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
v3:
- Change the processing logic. In v2, it just reported the warning
and returned error. But in v3, we also disable grouping.

tools/perf/builtin-stat.c | 4 +++
tools/perf/util/evlist-hybrid.c | 47 ++++++++++++++++++++++++++++++
tools/perf/util/evlist-hybrid.h | 2 ++
tools/perf/util/evsel.c | 6 ++++
tools/perf/util/evsel.h | 1 +
tools/perf/util/python-ext-sources | 2 ++
6 files changed, 62 insertions(+)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 33fda8f55f66..6f70a9f1971e 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -48,6 +48,7 @@
#include "util/pmu.h"
#include "util/event.h"
#include "util/evlist.h"
+#include "util/evlist-hybrid.h"
#include "util/evsel.h"
#include "util/debug.h"
#include "util/color.h"
@@ -240,6 +241,9 @@ static void evlist__check_cpu_maps(struct evlist *evlist)
struct evsel *evsel, *pos, *leader;
char buf[1024];

+ if (evlist__has_hybrid(evlist))
+ evlist__warn_hybrid_group(evlist);
+
evlist__for_each_entry(evlist, evsel) {
leader = evsel->leader;

diff --git a/tools/perf/util/evlist-hybrid.c b/tools/perf/util/evlist-hybrid.c
index 185f60ec4351..39f520372447 100644
--- a/tools/perf/util/evlist-hybrid.c
+++ b/tools/perf/util/evlist-hybrid.c
@@ -7,6 +7,7 @@
#include "../perf.h"
#include "util/pmu-hybrid.h"
#include "util/evlist-hybrid.h"
+#include "debug.h"
#include <unistd.h>
#include <stdlib.h>
#include <linux/err.h>
@@ -39,3 +40,49 @@ int evlist__add_default_hybrid(struct evlist *evlist, bool precise)

return 0;
}
+
+static bool group_hybrid_conflict(struct evsel *leader)
+{
+ struct evsel *pos, *prev = NULL;
+
+ for_each_group_evsel(pos, leader) {
+ if (!evsel__is_hybrid(pos))
+ continue;
+
+ if (prev && strcmp(prev->pmu_name, pos->pmu_name))
+ return true;
+
+ prev = pos;
+ }
+
+ return false;
+}
+
+void evlist__warn_hybrid_group(struct evlist *evlist)
+{
+ struct evsel *evsel;
+
+ evlist__for_each_entry(evlist, evsel) {
+ if (evsel__is_group_leader(evsel) &&
+ evsel->core.nr_members > 1 &&
+ group_hybrid_conflict(evsel)) {
+ pr_warning("WARNING: events in group from "
+ "different hybrid PMUs!\n");
+ return;
+ }
+ }
+}
+
+bool evlist__has_hybrid(struct evlist *evlist)
+{
+ struct evsel *evsel;
+
+ evlist__for_each_entry(evlist, evsel) {
+ if (evsel->pmu_name &&
+ perf_pmu__is_hybrid(evsel->pmu_name)) {
+ return true;
+ }
+ }
+
+ return false;
+}
diff --git a/tools/perf/util/evlist-hybrid.h b/tools/perf/util/evlist-hybrid.h
index e25861649d8f..19f74b4c340a 100644
--- a/tools/perf/util/evlist-hybrid.h
+++ b/tools/perf/util/evlist-hybrid.h
@@ -8,5 +8,7 @@
#include <unistd.h>

int evlist__add_default_hybrid(struct evlist *evlist, bool precise);
+void evlist__warn_hybrid_group(struct evlist *evlist);
+bool evlist__has_hybrid(struct evlist *evlist);

#endif /* __PERF_EVLIST_HYBRID_H */
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 0ba4daa09453..0f64a32ea9c5 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -47,6 +47,7 @@
#include "memswap.h"
#include "util.h"
#include "hashmap.h"
+#include "pmu-hybrid.h"
#include "../perf-sys.h"
#include "util/parse-branch-options.h"
#include <internal/xyarray.h>
@@ -2797,3 +2798,8 @@ void evsel__zero_per_pkg(struct evsel *evsel)
hashmap__clear(evsel->per_pkg_mask);
}
}
+
+bool evsel__is_hybrid(struct evsel *evsel)
+{
+ return evsel->pmu_name && perf_pmu__is_hybrid(evsel->pmu_name);
+}
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index e7dc3448ab2f..e56826bbb628 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -453,4 +453,5 @@ struct perf_env *evsel__env(struct evsel *evsel);
int evsel__store_ids(struct evsel *evsel, struct evlist *evlist);

void evsel__zero_per_pkg(struct evsel *evsel);
+bool evsel__is_hybrid(struct evsel *evsel);
#endif /* __PERF_EVSEL_H */
diff --git a/tools/perf/util/python-ext-sources b/tools/perf/util/python-ext-sources
index 845dd46e3c61..d7c976671e3a 100644
--- a/tools/perf/util/python-ext-sources
+++ b/tools/perf/util/python-ext-sources
@@ -37,3 +37,5 @@ util/units.c
util/affinity.c
util/rwsem.c
util/hashmap.c
+util/pmu-hybrid.c
+util/fncache.c
--
2.17.1