tools/perf/tests/task-exit.c

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