task-exit.c

  1// SPDX-License-Identifier: GPL-2.0
  2#include "debug.h"
  3#include "evlist.h"
  4#include "evsel.h"
  5#include "target.h"
  6#include "thread_map.h"
  7#include "tests.h"
  8#include "util/mmap.h"
  9
 10#include <errno.h>
 11#include <signal.h>
 12#include <linux/string.h>
 13#include <perf/cpumap.h>
 14#include <perf/evlist.h>
 15#include <perf/mmap.h>
 16
 17static int exited;
 18static int nr_exit;
 19
 20static void sig_handler(int sig __maybe_unused)
 21{
 22	exited = 1;
 23}
 24
 25/*
 26 * evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
 27 * we asked by setting its exec_error to this handler.
 28 */
 29static void workload_exec_failed_signal(int signo __maybe_unused,
 30					siginfo_t *info __maybe_unused,
 31					void *ucontext __maybe_unused)
 32{
 33	exited	= 1;
 34	nr_exit = -1;
 35}
 36
 37/*
 38 * This test will start a workload that does nothing then it checks
 39 * if the number of exit event reported by the kernel is 1 or not
 40 * in order to check the kernel returns correct number of event.
 41 */
 42static int test__task_exit(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
 43{
 44	int err = -1;
 45	union perf_event *event;
 46	struct evsel *evsel;
 47	struct evlist *evlist;
 48	struct target target = {
 49		.uses_mmap	= true,
 50	};
 51	const char *argv[] = { "true", NULL };
 52	char sbuf[STRERR_BUFSIZE];
 53	struct perf_cpu_map *cpus;
 54	struct perf_thread_map *threads;
 55	struct mmap *md;
 56	int retry_count = 0;
 57
 58	signal(SIGCHLD, sig_handler);
 59
 60	evlist = evlist__new_dummy();
 61	if (evlist == NULL) {
 62		pr_debug("evlist__new_dummy\n");
 63		return -1;
 64	}
 65
 66	/*
 67	 * Create maps of threads and cpus to monitor. In this case
 68	 * we start with all threads and cpus (-1, -1) but then in
 69	 * evlist__prepare_workload we'll fill in the only thread
 70	 * we're monitoring, the one forked there.
 71	 */
 72	cpus = perf_cpu_map__new_any_cpu();
 73	threads = thread_map__new_by_tid(-1);
 74	if (!cpus || !threads) {
 75		err = -ENOMEM;
 76		pr_debug("Not enough memory to create thread/cpu maps\n");
 77		goto out_delete_evlist;
 78	}
 79
 80	perf_evlist__set_maps(&evlist->core, cpus, threads);
 81
 82	err = evlist__prepare_workload(evlist, &target, argv, false, workload_exec_failed_signal);
 83	if (err < 0) {
 84		pr_debug("Couldn't run the workload!\n");
 85		goto out_delete_evlist;
 86	}
 87
 88	evsel = evlist__first(evlist);
 89	evsel->core.attr.task = 1;
 90#ifdef __s390x__
 91	evsel->core.attr.sample_freq = 1000000;
 92#else
 93	evsel->core.attr.sample_freq = 1;
 94#endif
 95	evsel->core.attr.inherit = 0;
 96	evsel->core.attr.watermark = 0;
 97	evsel->core.attr.wakeup_events = 1;
 98	evsel->core.attr.exclude_kernel = 1;
 99
100	err = evlist__open(evlist);
101	if (err < 0) {
102		pr_debug("Couldn't open the evlist: %s\n",
103			 str_error_r(-err, sbuf, sizeof(sbuf)));
104		goto out_delete_evlist;
105	}
106
107	if (evlist__mmap(evlist, 128) < 0) {
108		pr_debug("failed to mmap events: %d (%s)\n", errno,
109			 str_error_r(errno, sbuf, sizeof(sbuf)));
110		err = -1;
111		goto out_delete_evlist;
112	}
113
114	evlist__start_workload(evlist);
115
116retry:
117	md = &evlist->mmap[0];
118	if (perf_mmap__read_init(&md->core) < 0)
119		goto out_init;
120
121	while ((event = perf_mmap__read_event(&md->core)) != NULL) {
122		if (event->header.type == PERF_RECORD_EXIT)
123			nr_exit++;
124
125		perf_mmap__consume(&md->core);
126	}
127	perf_mmap__read_done(&md->core);
128
129out_init:
130	if (!exited || !nr_exit) {
131		evlist__poll(evlist, -1);
132
133		if (retry_count++ > 1000) {
134			pr_debug("Failed after retrying 1000 times\n");
135			err = -1;
136			goto out_delete_evlist;
137		}
138
139		goto retry;
140	}
141
142	if (nr_exit != 1) {
143		pr_debug("received %d EXIT records\n", nr_exit);
144		err = -1;
145	}
146
147out_delete_evlist:
148	perf_cpu_map__put(cpus);
149	perf_thread_map__put(threads);
150	evlist__delete(evlist);
151	return err;
152}
153
154struct test_case tests__task_exit[] = {
155	TEST_CASE_EXCLUSIVE("Number of exit events of a simple workload", task_exit),
156	{	.name = NULL, }
157};
158struct test_suite suite__task_exit = {
159	.desc = "Number of exit events of a simple workload",
160	.test_cases = tests__task_exit,
161};