Re: [PATCH 07/10] libperf: Add tests_mmap_cpus test

Arnaldo Carvalho de Melo
2019-10-18T18:14:39Z

Em Thu, Oct 17, 2019 at 12:59:15PM +0200, Jiri Olsa escreveu:
> Adding mmaping tests that generates prctl call on
> every cpu validates it gets all the related events
> in ring buffer.

So _here_ we need _GNU_SOURCE, for this specific test:

LINK test-evlist-a
test-evlist.c: In function ‘test_mmap_cpus’:
test-evlist.c:352:8: warning: implicit declaration of function ‘sched_getaffinity’ [-Wimplicit-function-declaration]
352 | err = sched_getaffinity(0, sizeof(saved_mask), &saved_mask);
| ^~~~~~~~~~~~~~~~~
test-evlist.c:358:3: warning: implicit declaration of function ‘CPU_ZERO’ [-Wimplicit-function-declaration]
358 | CPU_ZERO(&mask);
| ^~~~~~~~
test-evlist.c:359:3: warning: implicit declaration of function ‘CPU_SET’ [-Wimplicit-function-declaration]
359 | CPU_SET(cpu, &mask);
| ^~~~~~~
test-evlist.c:361:9: warning: implicit declaration of function ‘sched_setaffinity’ [-Wimplicit-function-declaration]
361 | err = sched_setaffinity(0, sizeof(mask), &mask);
| ^~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccOhNrLC.o: in function `test_mmap_cpus':
/home/acme/git/perf/tools/perf/lib/tests/test-evlist.c:358: undefined reference to `CPU_ZERO'
/usr/bin/ld: /home/acme/git/perf/tools/perf/lib/tests/test-evlist.c:359: undefined reference to `CPU_SET'
collect2: error: ld returned 1 exit status
make[1]: *** [Makefile:22: test-evlist-a] Error 1
make: *** [Makefile:143: tests] Error 2
make: Leaving directory '/home/acme/git/perf/tools/perf/lib'
[root@quaco perf]#

> 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

--

- Arnaldo