perf evlist: Add can_select_event() method
Add a function to determine whether an event can be selected.
This function is needed to allow a tool to automatically select
additional events, but only if they are available.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1386765443-26966-18-git-send-email-alexander.shishkin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/record.c b/tools/perf/util/record.c
index c8845b1..e510453 100644
--- a/tools/perf/util/record.c
+++ b/tools/perf/util/record.c
@@ -177,3 +177,40 @@
{
return perf_record_opts__config_freq(opts);
}
+
+bool perf_evlist__can_select_event(struct perf_evlist *evlist, const char *str)
+{
+ struct perf_evlist *temp_evlist;
+ struct perf_evsel *evsel;
+ int err, fd, cpu;
+ bool ret = false;
+
+ temp_evlist = perf_evlist__new();
+ if (!temp_evlist)
+ return false;
+
+ err = parse_events(temp_evlist, str);
+ if (err)
+ goto out_delete;
+
+ evsel = perf_evlist__last(temp_evlist);
+
+ if (!evlist || cpu_map__empty(evlist->cpus)) {
+ struct cpu_map *cpus = cpu_map__new(NULL);
+
+ cpu = cpus ? cpus->map[0] : 0;
+ cpu_map__delete(cpus);
+ } else {
+ cpu = evlist->cpus->map[0];
+ }
+
+ fd = sys_perf_event_open(&evsel->attr, -1, cpu, -1, 0);
+ if (fd >= 0) {
+ close(fd);
+ ret = true;
+ }
+
+out_delete:
+ perf_evlist__delete(temp_evlist);
+ return ret;
+}