tools/perf/tests/perf-time-to-tsc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <errno.h>
   3 #include <inttypes.h>
   4 #include <limits.h>
   5 #include <stdbool.h>
   6 #include <stdio.h>
   7 #include <unistd.h>
   8 #include <linux/types.h>
   9 #include <sys/prctl.h>
  10 #include <perf/cpumap.h>
  11 #include <perf/evlist.h>
  12 #include <perf/mmap.h>
  13
  14 #include "debug.h"
  15 #include "parse-events.h"
  16 #include "evlist.h"
  17 #include "evsel.h"
  18 #include "thread_map.h"
  19 #include "record.h"
  20 #include "tsc.h"
  21 #include "mmap.h"
  22 #include "tests.h"
  23
  24 #define CHECK__(x) {                            \
  25         while ((x) < 0) {                       \
  26                 pr_debug(#x " failed!\n");      \
  27                 goto out_err;                   \
  28         }                                       \
  29 }
  30
  31 #define CHECK_NOT_NULL__(x) {                   \
  32         while ((x) == NULL) {                   \
  33                 pr_debug(#x " failed!\n");      \
  34                 goto out_err;                   \
  35         }                                       \
  36 }
  37
  38 /**
  39  * test__perf_time_to_tsc - test converting perf time to TSC.
  40  *
  41  * This function implements a test that checks that the conversion of perf time
  42  * to and from TSC is consistent with the order of events.  If the test passes
  43  * %0 is returned, otherwise %-1 is returned.  If TSC conversion is not
  44  * supported then then the test passes but " (not supported)" is printed.
  45  */
  46 int test__perf_time_to_tsc(struct test *test __maybe_unused, int subtest __maybe_unused)
  47 {
  48         struct record_opts opts = {
  49                 .mmap_pages          = UINT_MAX,
  50                 .user_freq           = UINT_MAX,
  51                 .user_interval       = ULLONG_MAX,
  52                 .target              = {
  53                         .uses_mmap   = true,
  54                 },
  55                 .sample_time         = true,
  56         };
  57         struct perf_thread_map *threads = NULL;
  58         struct perf_cpu_map *cpus = NULL;
  59         struct evlist *evlist = NULL;
  60         struct evsel *evsel = NULL;
  61         int err = -1, ret, i;
  62         const char *comm1, *comm2;
  63         struct perf_tsc_conversion tc;
  64         struct perf_event_mmap_page *pc;
  65         union perf_event *event;
  66         u64 test_tsc, comm1_tsc, comm2_tsc;
  67         u64 test_time, comm1_time = 0, comm2_time = 0;
  68         struct mmap *md;
  69
  70         threads = thread_map__new(-1, getpid(), UINT_MAX);
  71         CHECK_NOT_NULL__(threads);
  72
  73         cpus = perf_cpu_map__new(NULL);
  74         CHECK_NOT_NULL__(cpus);
  75
  76         evlist = evlist__new();
  77         CHECK_NOT_NULL__(evlist);
  78
  79         perf_evlist__set_maps(&evlist->core, cpus, threads);
  80
  81         CHECK__(parse_events(evlist, "cycles:u", NULL));
  82
  83         evlist__config(evlist, &opts, NULL);
  84
  85         evsel = evlist__first(evlist);
  86
  87         evsel->core.attr.comm = 1;
  88         evsel->core.attr.disabled = 1;
  89         evsel->core.attr.enable_on_exec = 0;
  90
  91         CHECK__(evlist__open(evlist));
  92
  93         CHECK__(evlist__mmap(evlist, UINT_MAX));
  94
  95         pc = evlist->mmap[0].core.base;
  96         ret = perf_read_tsc_conversion(pc, &tc);
  97         if (ret) {
  98                 if (ret == -EOPNOTSUPP) {
  99                         fprintf(stderr, " (not supported)");
 100                         return 0;
 101                 }
 102                 goto out_err;
 103         }
 104
 105         evlist__enable(evlist);
 106
 107         comm1 = "Test COMM 1";
 108         CHECK__(prctl(PR_SET_NAME, (unsigned long)comm1, 0, 0, 0));
 109
 110         test_tsc = rdtsc();
 111
 112         comm2 = "Test COMM 2";
 113         CHECK__(prctl(PR_SET_NAME, (unsigned long)comm2, 0, 0, 0));
 114
 115         evlist__disable(evlist);
 116
 117         for (i = 0; i < evlist->core.nr_mmaps; i++) {
 118                 md = &evlist->mmap[i];
 119                 if (perf_mmap__read_init(&md->core) < 0)
 120                         continue;
 121
 122                 while ((event = perf_mmap__read_event(&md->core)) != NULL) {
 123                         struct perf_sample sample;
 124
 125                         if (event->header.type != PERF_RECORD_COMM ||
 126                             (pid_t)event->comm.pid != getpid() ||
 127                             (pid_t)event->comm.tid != getpid())
 128                                 goto next_event;
 129
 130                         if (strcmp(event->comm.comm, comm1) == 0) {
 131                                 CHECK__(evsel__parse_sample(evsel, event, &sample));
 132                                 comm1_time = sample.time;
 133                         }
 134                         if (strcmp(event->comm.comm, comm2) == 0) {
 135                                 CHECK__(evsel__parse_sample(evsel, event, &sample));
 136                                 comm2_time = sample.time;
 137                         }
 138 next_event:
 139                         perf_mmap__consume(&md->core);
 140                 }
 141                 perf_mmap__read_done(&md->core);
 142         }
 143
 144         if (!comm1_time || !comm2_time)
 145                 goto out_err;
 146
 147         test_time = tsc_to_perf_time(test_tsc, &tc);
 148         comm1_tsc = perf_time_to_tsc(comm1_time, &tc);
 149         comm2_tsc = perf_time_to_tsc(comm2_time, &tc);
 150
 151         pr_debug("1st event perf time %"PRIu64" tsc %"PRIu64"\n",
 152                  comm1_time, comm1_tsc);
 153         pr_debug("rdtsc          time %"PRIu64" tsc %"PRIu64"\n",
 154                  test_time, test_tsc);
 155         pr_debug("2nd event perf time %"PRIu64" tsc %"PRIu64"\n",
 156                  comm2_time, comm2_tsc);
 157
 158         if (test_time <= comm1_time ||
 159             test_time >= comm2_time)
 160                 goto out_err;
 161
 162         if (test_tsc <= comm1_tsc ||
 163             test_tsc >= comm2_tsc)
 164                 goto out_err;
 165
 166         err = 0;
 167
 168 out_err:
 169         evlist__delete(evlist);
 170         return err;
 171 }
 172
 173 bool test__tsc_is_supported(void)
 174 {
 175         /*
 176          * Except x86_64/i386 and Arm64, other archs don't support TSC in perf.
 177          * Just enable the test for x86_64/i386 and Arm64 archs.
 178          */
 179 #if defined(__x86_64__) || defined(__i386__) || defined(__aarch64__)
 180         return true;
 181 #else
 182         return false;
 183 #endif
 184 }