LXR linux/tools/perf/tests/keep-tracking.c

   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/types.h>
   3#include <unistd.h>
   4#include <sys/prctl.h>
   5
   6#include "parse-events.h"
   7#include "evlist.h"
   8#include "evsel.h"
   9#include "thread_map.h"
  10#include "cpumap.h"
  11#include "tests.h"
  12
  13#define CHECK__(x) {                            \
  14        while ((x) < 0) {                       \
  15                pr_debug(#x " failed!\n");      \
  16                goto out_err;                   \
  17        }                                       \
  18}
  19
  20#define CHECK_NOT_NULL__(x) {                   \
  21        while ((x) == NULL) {                   \
  22                pr_debug(#x " failed!\n");      \
  23                goto out_err;                   \
  24        }                                       \
  25}
  26
  27static int find_comm(struct perf_evlist *evlist, const char *comm)
  28{
  29        union perf_event *event;
  30        int i, found;
  31
  32        found = 0;
  33        for (i = 0; i < evlist->nr_mmaps; i++) {
  34                while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
  35                        if (event->header.type == PERF_RECORD_COMM &&
  36                            (pid_t)event->comm.pid == getpid() &&
  37                            (pid_t)event->comm.tid == getpid() &&
  38                            strcmp(event->comm.comm, comm) == 0)
  39                                found += 1;
  40                        perf_evlist__mmap_consume(evlist, i);
  41                }
  42        }
  43        return found;
  44}
  45
  46/**
  47 * test__keep_tracking - test using a dummy software event to keep tracking.
  48 *
  49 * This function implements a test that checks that tracking events continue
  50 * when an event is disabled but a dummy software event is not disabled.  If the
  51 * test passes %0 is returned, otherwise %-1 is returned.
  52 */
  53int test__keep_tracking(struct test *test __maybe_unused, int subtest __maybe_unused)
  54{
  55        struct record_opts opts = {
  56                .mmap_pages          = UINT_MAX,
  57                .user_freq           = UINT_MAX,
  58                .user_interval       = ULLONG_MAX,
  59                .target              = {
  60                        .uses_mmap   = true,
  61                },
  62        };
  63        struct thread_map *threads = NULL;
  64        struct cpu_map *cpus = NULL;
  65        struct perf_evlist *evlist = NULL;
  66        struct perf_evsel *evsel = NULL;
  67        int found, err = -1;
  68        const char *comm;
  69
  70        threads = thread_map__new(-1, getpid(), UINT_MAX);
  71        CHECK_NOT_NULL__(threads);
  72
  73        cpus = cpu_map__new(NULL);
  74        CHECK_NOT_NULL__(cpus);
  75
  76        evlist = perf_evlist__new();
  77        CHECK_NOT_NULL__(evlist);
  78
  79        perf_evlist__set_maps(evlist, cpus, threads);
  80
  81        CHECK__(parse_events(evlist, "dummy:u", NULL));
  82        CHECK__(parse_events(evlist, "cycles:u", NULL));
  83
  84        perf_evlist__config(evlist, &opts, NULL);
  85
  86        evsel = perf_evlist__first(evlist);
  87
  88        evsel->attr.comm = 1;
  89        evsel->attr.disabled = 1;
  90        evsel->attr.enable_on_exec = 0;
  91
  92        if (perf_evlist__open(evlist) < 0) {
  93                pr_debug("Unable to open dummy and cycles event\n");
  94                err = TEST_SKIP;
  95                goto out_err;
  96        }
  97
  98        CHECK__(perf_evlist__mmap(evlist, UINT_MAX));
  99
 100        /*
 101         * First, test that a 'comm' event can be found when the event is
 102         * enabled.
 103         */
 104
 105        perf_evlist__enable(evlist);
 106
 107        comm = "Test COMM 1";
 108        CHECK__(prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0));
 109
 110        perf_evlist__disable(evlist);
 111
 112        found = find_comm(evlist, comm);
 113        if (found != 1) {
 114                pr_debug("First time, failed to find tracking event.\n");
 115                goto out_err;
 116        }
 117
 118        /*
 119         * Secondly, test that a 'comm' event can be found when the event is
 120         * disabled with the dummy event still enabled.
 121         */
 122
 123        perf_evlist__enable(evlist);
 124
 125        evsel = perf_evlist__last(evlist);
 126
 127        CHECK__(perf_evsel__disable(evsel));
 128
 129        comm = "Test COMM 2";
 130        CHECK__(prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0));
 131
 132        perf_evlist__disable(evlist);
 133
 134        found = find_comm(evlist, comm);
 135        if (found != 1) {
 136                pr_debug("Seconf time, failed to find tracking event.\n");
 137                goto out_err;
 138        }
 139
 140        err = 0;
 141
 142out_err:
 143        if (evlist) {
 144                perf_evlist__disable(evlist);
 145                perf_evlist__delete(evlist);
 146        } else {
 147                cpu_map__put(cpus);
 148                thread_map__put(threads);
 149        }
 150
 151        return err;
 152}
 153