perf evsel: Support event groups
The perf_evsel__open now have an extra boolean argument specifying if
event grouping is desired.
The first file descriptor created on a CPU becomes the group leader.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index f5cfed6..da473ec 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -128,7 +128,7 @@
}
static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
- struct thread_map *threads)
+ struct thread_map *threads, bool group)
{
int cpu, thread;
@@ -137,12 +137,18 @@
return -1;
for (cpu = 0; cpu < cpus->nr; cpu++) {
+ int group_fd = -1;
+
for (thread = 0; thread < threads->nr; thread++) {
FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
threads->map[thread],
- cpus->map[cpu], -1, 0);
+ cpus->map[cpu],
+ group_fd, 0);
if (FD(evsel, cpu, thread) < 0)
goto out_close;
+
+ if (group && group_fd == -1)
+ group_fd = FD(evsel, cpu, thread);
}
}
@@ -175,10 +181,9 @@
.threads = { -1, },
};
-int perf_evsel__open(struct perf_evsel *evsel,
- struct cpu_map *cpus, struct thread_map *threads)
+int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
+ struct thread_map *threads, bool group)
{
-
if (cpus == NULL) {
/* Work around old compiler warnings about strict aliasing */
cpus = &empty_cpu_map.map;
@@ -187,15 +192,17 @@
if (threads == NULL)
threads = &empty_thread_map.map;
- return __perf_evsel__open(evsel, cpus, threads);
+ return __perf_evsel__open(evsel, cpus, threads, group);
}
-int perf_evsel__open_per_cpu(struct perf_evsel *evsel, struct cpu_map *cpus)
+int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
+ struct cpu_map *cpus, bool group)
{
- return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
+ return __perf_evsel__open(evsel, cpus, &empty_thread_map.map, group);
}
-int perf_evsel__open_per_thread(struct perf_evsel *evsel, struct thread_map *threads)
+int perf_evsel__open_per_thread(struct perf_evsel *evsel,
+ struct thread_map *threads, bool group)
{
- return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
+ return __perf_evsel__open(evsel, &empty_cpu_map.map, threads, group);
}