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

   1 #include <stdio.h>
   2 #include <sys/types.h>
   3 #include <unistd.h>
   4 #include <inttypes.h>
   5 #include <sys/prctl.h>
   6
   7 #include "parse-events.h"
   8 #include "evlist.h"
   9 #include "evsel.h"
  10 #include "thread_map.h"
  11 #include "cpumap.h"
  12 #include "tests.h"
  13
  14 #include "../arch/x86/util/tsc.h"
  15
  16 #define CHECK__(x) {                            \
  17         while ((x) < 0) {                       \
  18                 pr_debug(#x " failed!\n");      \
  19                 goto out_err;                   \
  20         }                                       \
  21 }
  22
  23 #define CHECK_NOT_NULL__(x) {                   \
  24         while ((x) == NULL) {                   \
  25                 pr_debug(#x " failed!\n");      \
  26                 goto out_err;                   \
  27         }                                       \
  28 }
  29
  30 static u64 rdtsc(void)
  31 {
  32         unsigned int low, high;
  33
  34         asm volatile("rdtsc" : "=a" (low), "=d" (high));
  35
  36         return low | ((u64)high) << 32;
  37 }
  38
  39 /**
  40  * test__perf_time_to_tsc - test converting perf time to TSC.
  41  *
  42  * This function implements a test that checks that the conversion of perf time
  43  * to and from TSC is consistent with the order of events.  If the test passes
  44  * %0 is returned, otherwise %-1 is returned.  If TSC conversion is not
  45  * supported then then the test passes but " (not supported)" is printed.
  46  */
  47 int test__perf_time_to_tsc(void)
  48 {
  49         struct perf_record_opts opts = {
  50                 .mmap_pages          = UINT_MAX,
  51                 .user_freq           = UINT_MAX,
  52                 .user_interval       = ULLONG_MAX,
  53                 .freq                = 4000,
  54                 .target              = {
  55                         .uses_mmap   = true,
  56                 },
  57                 .sample_time         = true,
  58         };
  59         struct thread_map *threads = NULL;
  60         struct cpu_map *cpus = NULL;
  61         struct perf_evlist *evlist = NULL;
  62         struct perf_evsel *evsel = NULL;
  63         int err = -1, ret, i;
  64         const char *comm1, *comm2;
  65         struct perf_tsc_conversion tc;
  66         struct perf_event_mmap_page *pc;
  67         union perf_event *event;
  68         u64 test_tsc, comm1_tsc, comm2_tsc;
  69         u64 test_time, comm1_time = 0, comm2_time = 0;
  70
  71         threads = thread_map__new(-1, getpid(), UINT_MAX);
  72         CHECK_NOT_NULL__(threads);
  73
  74         cpus = cpu_map__new(NULL);
  75         CHECK_NOT_NULL__(cpus);
  76
  77         evlist = perf_evlist__new();
  78         CHECK_NOT_NULL__(evlist);
  79
  80         perf_evlist__set_maps(evlist, cpus, threads);
  81
  82         CHECK__(parse_events(evlist, "cycles:u"));
  83
  84         perf_evlist__config(evlist, &opts);
  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         CHECK__(perf_evlist__open(evlist));
  93
  94         CHECK__(perf_evlist__mmap(evlist, UINT_MAX, false));
  95
  96         pc = evlist->mmap[0].base;
  97         ret = perf_read_tsc_conversion(pc, &tc);
  98         if (ret) {
  99                 if (ret == -EOPNOTSUPP) {
 100                         fprintf(stderr, " (not supported)");
 101                         return 0;
 102                 }
 103                 goto out_err;
 104         }
 105
 106         perf_evlist__enable(evlist);
 107
 108         comm1 = "Test COMM 1";
 109         CHECK__(prctl(PR_SET_NAME, (unsigned long)comm1, 0, 0, 0));
 110
 111         test_tsc = rdtsc();
 112
 113         comm2 = "Test COMM 2";
 114         CHECK__(prctl(PR_SET_NAME, (unsigned long)comm2, 0, 0, 0));
 115
 116         perf_evlist__disable(evlist);
 117
 118         for (i = 0; i < evlist->nr_mmaps; i++) {
 119                 while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
 120                         struct perf_sample sample;
 121
 122                         if (event->header.type != PERF_RECORD_COMM ||
 123                             (pid_t)event->comm.pid != getpid() ||
 124                             (pid_t)event->comm.tid != getpid())
 125                                 goto next_event;
 126
 127                         if (strcmp(event->comm.comm, comm1) == 0) {
 128                                 CHECK__(perf_evsel__parse_sample(evsel, event,
 129                                                                  &sample));
 130                                 comm1_time = sample.time;
 131                         }
 132                         if (strcmp(event->comm.comm, comm2) == 0) {
 133                                 CHECK__(perf_evsel__parse_sample(evsel, event,
 134                                                                  &sample));
 135                                 comm2_time = sample.time;
 136                         }
 137 next_event:
 138                         perf_evlist__mmap_consume(evlist, i);
 139                 }
 140         }
 141
 142         if (!comm1_time || !comm2_time)
 143                 goto out_err;
 144
 145         test_time = tsc_to_perf_time(test_tsc, &tc);
 146         comm1_tsc = perf_time_to_tsc(comm1_time, &tc);
 147         comm2_tsc = perf_time_to_tsc(comm2_time, &tc);
 148
 149         pr_debug("1st event perf time %"PRIu64" tsc %"PRIu64"\n",
 150                  comm1_time, comm1_tsc);
 151         pr_debug("rdtsc          time %"PRIu64" tsc %"PRIu64"\n",
 152                  test_time, test_tsc);
 153         pr_debug("2nd event perf time %"PRIu64" tsc %"PRIu64"\n",
 154                  comm2_time, comm2_tsc);
 155
 156         if (test_time <= comm1_time ||
 157             test_time >= comm2_time)
 158                 goto out_err;
 159
 160         if (test_tsc <= comm1_tsc ||
 161             test_tsc >= comm2_tsc)
 162                 goto out_err;
 163
 164         err = 0;
 165
 166 out_err:
 167         if (evlist) {
 168                 perf_evlist__disable(evlist);
 169                 perf_evlist__munmap(evlist);
 170                 perf_evlist__close(evlist);
 171                 perf_evlist__delete(evlist);
 172         }
 173         if (cpus)
 174                 cpu_map__delete(cpus);
 175         if (threads)
 176                 thread_map__delete(threads);
 177
 178         return err;
 179 }