LXR linux/tools/perf/tests/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 */
  42int test__task_exit(struct test *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                .uid            = UINT_MAX,
  50                .uses_mmap      = true,
  51        };
  52        const char *argv[] = { "true", NULL };
  53        char sbuf[STRERR_BUFSIZE];
  54        struct perf_cpu_map *cpus;
  55        struct perf_thread_map *threads;
  56        struct mmap *md;
  57        int retry_count = 0;
  58
  59        signal(SIGCHLD, sig_handler);
  60
  61        evlist = evlist__new_default();
  62        if (evlist == NULL) {
  63                pr_debug("evlist__new_default\n");
  64                return -1;
  65        }
  66
  67        /*
  68         * Create maps of threads and cpus to monitor. In this case
  69         * we start with all threads and cpus (-1, -1) but then in
  70         * evlist__prepare_workload we'll fill in the only thread
  71         * we're monitoring, the one forked there.
  72         */
  73        cpus = perf_cpu_map__dummy_new();
  74        threads = thread_map__new_by_tid(-1);
  75        if (!cpus || !threads) {
  76                err = -ENOMEM;
  77                pr_debug("Not enough memory to create thread/cpu maps\n");
  78                goto out_delete_evlist;
  79        }
  80
  81        perf_evlist__set_maps(&evlist->core, cpus, threads);
  82
  83        err = evlist__prepare_workload(evlist, &target, argv, false, workload_exec_failed_signal);
  84        if (err < 0) {
  85                pr_debug("Couldn't run the workload!\n");
  86                goto out_delete_evlist;
  87        }
  88
  89        evsel = evlist__first(evlist);
  90        evsel->core.attr.task = 1;
  91#ifdef __s390x__
  92        evsel->core.attr.sample_freq = 1000000;
  93#else
  94        evsel->core.attr.sample_freq = 1;
  95#endif
  96        evsel->core.attr.inherit = 0;
  97        evsel->core.attr.watermark = 0;
  98        evsel->core.attr.wakeup_events = 1;
  99        evsel->core.attr.exclude_kernel = 1;
 100
 101        err = evlist__open(evlist);
 102        if (err < 0) {
 103                pr_debug("Couldn't open the evlist: %s\n",
 104                         str_error_r(-err, sbuf, sizeof(sbuf)));
 105                goto out_delete_evlist;
 106        }
 107
 108        if (evlist__mmap(evlist, 128) < 0) {
 109                pr_debug("failed to mmap events: %d (%s)\n", errno,
 110                         str_error_r(errno, sbuf, sizeof(sbuf)));
 111                err = -1;
 112                goto out_delete_evlist;
 113        }
 114
 115        evlist__start_workload(evlist);
 116
 117retry:
 118        md = &evlist->mmap[0];
 119        if (perf_mmap__read_init(&md->core) < 0)
 120                goto out_init;
 121
 122        while ((event = perf_mmap__read_event(&md->core)) != NULL) {
 123                if (event->header.type == PERF_RECORD_EXIT)
 124                        nr_exit++;
 125
 126                perf_mmap__consume(&md->core);
 127        }
 128        perf_mmap__read_done(&md->core);
 129
 130out_init:
 131        if (!exited || !nr_exit) {
 132                evlist__poll(evlist, -1);
 133
 134                if (retry_count++ > 1000) {
 135                        pr_debug("Failed after retrying 1000 times\n");
 136                        err = -1;
 137                        goto out_delete_evlist;
 138                }
 139
 140                goto retry;
 141        }
 142
 143        if (nr_exit != 1) {
 144                pr_debug("received %d EXIT records\n", nr_exit);
 145                err = -1;
 146        }
 147
 148out_delete_evlist:
 149        perf_cpu_map__put(cpus);
 150        perf_thread_map__put(threads);
 151        evlist__delete(evlist);
 152        return err;
 153}
 154