1 files changed, 29 insertions, 6 deletions

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index f4dea055b080..a69e64236120 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1223,16 +1223,27 @@ int perf_evsel__append_addr_filter(struct evsel *evsel, const char *filter)
 	return perf_evsel__append_filter(evsel, "%s,%s", filter);
 }
 
+/* Caller has to clear disabled after going through all CPUs. */
+int evsel__enable_cpu(struct evsel *evsel, int cpu)
+{
+	return perf_evsel__enable_cpu(&evsel->core, cpu);
+}
+
 int evsel__enable(struct evsel *evsel)
 {
 	int err = perf_evsel__enable(&evsel->core);
 
 	if (!err)
 		evsel->disabled = false;
-
 	return err;
 }
 
+/* Caller has to set disabled after going through all CPUs. */
+int evsel__disable_cpu(struct evsel *evsel, int cpu)
+{
+	return perf_evsel__disable_cpu(&evsel->core, cpu);
+}
+
 int evsel__disable(struct evsel *evsel)
 {
 	int err = perf_evsel__disable(&evsel->core);
@@ -1587,8 +1598,9 @@ static int perf_event_open(struct evsel *evsel,
 	return fd;
 }
 
-int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
-		struct perf_thread_map *threads)
+static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
+		struct perf_thread_map *threads,
+		int start_cpu, int end_cpu)
 {
 	int cpu, thread, nthreads;
 	unsigned long flags = PERF_FLAG_FD_CLOEXEC;
@@ -1665,7 +1677,7 @@ retry_sample_id:
 
 	display_attr(&evsel->core.attr);
 
-	for (cpu = 0; cpu < cpus->nr; cpu++) {
+	for (cpu = start_cpu; cpu < end_cpu; cpu++) {
 
 		for (thread = 0; thread < nthreads; thread++) {
 			int fd, group_fd;
@@ -1843,6 +1855,12 @@ out_close:
 	return err;
 }
 
+int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
+		struct perf_thread_map *threads)
+{
+	return evsel__open_cpu(evsel, cpus, threads, 0, cpus ? cpus->nr : 1);
+}
+
 void evsel__close(struct evsel *evsel)
 {
 	perf_evsel__close(&evsel->core);
@@ -1850,9 +1868,14 @@ void evsel__close(struct evsel *evsel)
 }
 
 int perf_evsel__open_per_cpu(struct evsel *evsel,
-			     struct perf_cpu_map *cpus)
+			     struct perf_cpu_map *cpus,
+			     int cpu)
 {
-	return evsel__open(evsel, cpus, NULL);
+	if (cpu == -1)
+		return evsel__open_cpu(evsel, cpus, NULL, 0,
+					cpus ? cpus->nr : 1);
+
+	return evsel__open_cpu(evsel, cpus, NULL, cpu, cpu + 1);
 }
 
 int perf_evsel__open_per_thread(struct evsel *evsel,