swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: 4b972a01a7da614b4796475f933094751a295a2f authored by Linus Torvalds on 22 June 2019, 23:01:36 UTC
Linux 5.2-rc6
Linux 5.2-rc6
Tip revision: 4b972a0
task-exit.c
// SPDX-License-Identifier: GPL-2.0
#include "evlist.h"
#include "evsel.h"
#include "thread_map.h"
#include "cpumap.h"
#include "tests.h"
#include <errno.h>
#include <signal.h>
static int exited;
static int nr_exit;
static void sig_handler(int sig __maybe_unused)
{
exited = 1;
}
/*
* perf_evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
* we asked by setting its exec_error to this handler.
*/
static void workload_exec_failed_signal(int signo __maybe_unused,
siginfo_t *info __maybe_unused,
void *ucontext __maybe_unused)
{
exited = 1;
nr_exit = -1;
}
/*
* This test will start a workload that does nothing then it checks
* if the number of exit event reported by the kernel is 1 or not
* in order to check the kernel returns correct number of event.
*/
int test__task_exit(struct test *test __maybe_unused, int subtest __maybe_unused)
{
int err = -1;
union perf_event *event;
struct perf_evsel *evsel;
struct perf_evlist *evlist;
struct target target = {
.uid = UINT_MAX,
.uses_mmap = true,
};
const char *argv[] = { "true", NULL };
char sbuf[STRERR_BUFSIZE];
struct cpu_map *cpus;
struct thread_map *threads;
struct perf_mmap *md;
signal(SIGCHLD, sig_handler);
evlist = perf_evlist__new_default();
if (evlist == NULL) {
pr_debug("perf_evlist__new_default\n");
return -1;
}
/*
* Create maps of threads and cpus to monitor. In this case
* we start with all threads and cpus (-1, -1) but then in
* perf_evlist__prepare_workload we'll fill in the only thread
* we're monitoring, the one forked there.
*/
cpus = cpu_map__dummy_new();
threads = thread_map__new_by_tid(-1);
if (!cpus || !threads) {
err = -ENOMEM;
pr_debug("Not enough memory to create thread/cpu maps\n");
goto out_free_maps;
}
perf_evlist__set_maps(evlist, cpus, threads);
cpus = NULL;
threads = NULL;
err = perf_evlist__prepare_workload(evlist, &target, argv, false,
workload_exec_failed_signal);
if (err < 0) {
pr_debug("Couldn't run the workload!\n");
goto out_delete_evlist;
}
evsel = perf_evlist__first(evlist);
evsel->attr.task = 1;
#ifdef __s390x__
evsel->attr.sample_freq = 1000000;
#else
evsel->attr.sample_freq = 1;
#endif
evsel->attr.inherit = 0;
evsel->attr.watermark = 0;
evsel->attr.wakeup_events = 1;
evsel->attr.exclude_kernel = 1;
err = perf_evlist__open(evlist);
if (err < 0) {
pr_debug("Couldn't open the evlist: %s\n",
str_error_r(-err, sbuf, sizeof(sbuf)));
goto out_delete_evlist;
}
if (perf_evlist__mmap(evlist, 128) < 0) {
pr_debug("failed to mmap events: %d (%s)\n", errno,
str_error_r(errno, sbuf, sizeof(sbuf)));
goto out_delete_evlist;
}
perf_evlist__start_workload(evlist);
retry:
md = &evlist->mmap[0];
if (perf_mmap__read_init(md) < 0)
goto out_init;
while ((event = perf_mmap__read_event(md)) != NULL) {
if (event->header.type == PERF_RECORD_EXIT)
nr_exit++;
perf_mmap__consume(md);
}
perf_mmap__read_done(md);
out_init:
if (!exited || !nr_exit) {
perf_evlist__poll(evlist, -1);
goto retry;
}
if (nr_exit != 1) {
pr_debug("received %d EXIT records\n", nr_exit);
err = -1;
}
out_free_maps:
cpu_map__put(cpus);
thread_map__put(threads);
out_delete_evlist:
perf_evlist__delete(evlist);
return err;
}