[PATCH 07/10] libperf: Add tests_mmap_cpus test

Jiri Olsa
2019-10-17T10:59:46Z

Adding mmaping tests that generates prctl call on
every cpu validates it gets all the related events
in ring buffer.

Link: http://lkml.kernel.org/n/tip-9qdckblmgjm42ofd7haflso0@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/perf/lib/tests/test-evlist.c | 97 ++++++++++++++++++++++++++++++
1 file changed, 97 insertions(+)

diff --git a/tools/perf/lib/tests/test-evlist.c b/tools/perf/lib/tests/test-evlist.c
index 90a1869ba4b1..d8c52ebfa53a 100644
--- a/tools/perf/lib/tests/test-evlist.c
+++ b/tools/perf/lib/tests/test-evlist.c
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
#include <stdio.h>
+#include <sched.h>
#include <stdarg.h>
#include <unistd.h>
#include <stdlib.h>
@@ -299,6 +300,101 @@ static int test_mmap_thread(void)
return 0;
}

+static int test_mmap_cpus(void)
+{
+ struct perf_evlist *evlist;
+ struct perf_evsel *evsel;
+ struct perf_mmap *map;
+ struct perf_cpu_map *cpus;
+ struct perf_event_attr attr = {
+ .type = PERF_TYPE_TRACEPOINT,
+ .sample_period = 1,
+ .wakeup_watermark = 1,
+ .disabled = 1,
+ };
+ cpu_set_t saved_mask;
+ char path[PATH_MAX];
+ int id, err, cpu, tmp;
+ union perf_event *event;
+ int count = 0;
+
+ snprintf(path, PATH_MAX, "%s/kernel/debug/tracing/events/syscalls/sys_enter_prctl/id",
+ sysfs__mountpoint());
+
+ if (filename__read_int(path, &id)) {
+ fprintf(stderr, "error: failed to get tracepoint id: %s\n", path);
+ return -1;
+ }
+
+ attr.config = id;
+
+ cpus = perf_cpu_map__new(NULL);
+ __T("failed to create cpus", cpus);
+
+ evlist = perf_evlist__new();
+ __T("failed to create evlist", evlist);
+
+ evsel = perf_evsel__new(&attr);
+ __T("failed to create evsel1", evsel);
+
+ perf_evlist__add(evlist, evsel);
+
+ perf_evlist__set_maps(evlist, cpus, NULL);
+
+ err = perf_evlist__open(evlist);
+ __T("failed to open evlist", err == 0);
+
+ err = perf_evlist__mmap(evlist, 4);
+ __T("failed to mmap evlist", err == 0);
+
+ perf_evlist__enable(evlist);
+
+ err = sched_getaffinity(0, sizeof(saved_mask), &saved_mask);
+ __T("sched_getaffinity failed", err == 0);
+
+ perf_cpu_map__for_each_cpu(cpu, tmp, cpus) {
+ cpu_set_t mask;
+
+ CPU_ZERO(&mask);
+ CPU_SET(cpu, &mask);
+
+ err = sched_setaffinity(0, sizeof(mask), &mask);
+ __T("sched_setaffinity failed", err == 0);
+
+ prctl(0, 0, 0, 0, 0);
+ }
+
+ err = sched_setaffinity(0, sizeof(saved_mask), &saved_mask);
+ __T("sched_setaffinity failed", err == 0);
+
+ perf_evlist__disable(evlist);
+
+ perf_evlist__for_each_mmap(evlist, map, false) {
+ if (perf_mmap__read_init(map) < 0)
+ continue;
+
+ while ((event = perf_mmap__read_event(map)) != NULL) {
+ count++;
+ perf_mmap__consume(map);
+ }
+
+ perf_mmap__read_done(map);
+ }
+
+ /* calls perf_evlist__munmap/perf_evlist__close */
+ perf_evlist__delete(evlist);
+
+ /*
+ * The generated prctl events should match the
+ * number of cpus or be bigger (we are system-wide).
+ */
+ __T("failed count", count >= perf_cpu_map__nr(cpus));
+
+ perf_cpu_map__put(cpus);
+
+ return 0;
+}
+
int main(int argc, char **argv)
{
__T_START;
@@ -309,6 +405,7 @@ int main(int argc, char **argv)
test_stat_thread();
test_stat_thread_enable();
test_mmap_thread();
+ test_mmap_cpus();

__T_OK;
return 0;
--
2.21.0