tools/perf/tests/perf-record.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <errno.h>
   3 #include <inttypes.h>
   4 #include <linux/string.h>
   5 /* For the CLR_() macros */
   6 #include <pthread.h>
   7
   8 #include <sched.h>
   9 #include <perf/mmap.h>
  10 #include "evlist.h"
  11 #include "evsel.h"
  12 #include "debug.h"
  13 #include "record.h"
  14 #include "tests.h"
  15 #include "util/mmap.h"
  16
  17 static int sched__get_first_possible_cpu(pid_t pid, cpu_set_t *maskp)
  18 {
  19         int i, cpu = -1, nrcpus = 1024;
  20 realloc:
  21         CPU_ZERO(maskp);
  22
  23         if (sched_getaffinity(pid, sizeof(*maskp), maskp) == -1) {
  24                 if (errno == EINVAL && nrcpus < (1024 << 8)) {
  25                         nrcpus = nrcpus << 2;
  26                         goto realloc;
  27                 }
  28                 perror("sched_getaffinity");
  29                         return -1;
  30         }
  31
  32         for (i = 0; i < nrcpus; i++) {
  33                 if (CPU_ISSET(i, maskp)) {
  34                         if (cpu == -1)
  35                                 cpu = i;
  36                         else
  37                                 CPU_CLR(i, maskp);
  38                 }
  39         }
  40
  41         return cpu;
  42 }
  43
  44 int test__PERF_RECORD(struct test *test __maybe_unused, int subtest __maybe_unused)
  45 {
  46         struct record_opts opts = {
  47                 .target = {
  48                         .uid = UINT_MAX,
  49                         .uses_mmap = true,
  50                 },
  51                 .no_buffering = true,
  52                 .mmap_pages   = 256,
  53         };
  54         cpu_set_t cpu_mask;
  55         size_t cpu_mask_size = sizeof(cpu_mask);
  56         struct evlist *evlist = perf_evlist__new_dummy();
  57         struct evsel *evsel;
  58         struct perf_sample sample;
  59         const char *cmd = "sleep";
  60         const char *argv[] = { cmd, "1", NULL, };
  61         char *bname, *mmap_filename;
  62         u64 prev_time = 0;
  63         bool found_cmd_mmap = false,
  64              found_coreutils_mmap = false,
  65              found_libc_mmap = false,
  66              found_vdso_mmap = false,
  67              found_ld_mmap = false;
  68         int err = -1, errs = 0, i, wakeups = 0;
  69         u32 cpu;
  70         int total_events = 0, nr_events[PERF_RECORD_MAX] = { 0, };
  71         char sbuf[STRERR_BUFSIZE];
  72
  73         if (evlist == NULL) /* Fallback for kernels lacking PERF_COUNT_SW_DUMMY */
  74                 evlist = perf_evlist__new_default();
  75
  76         if (evlist == NULL) {
  77                 pr_debug("Not enough memory to create evlist\n");
  78                 goto out;
  79         }
  80
  81         /*
  82          * Create maps of threads and cpus to monitor. In this case
  83          * we start with all threads and cpus (-1, -1) but then in
  84          * perf_evlist__prepare_workload we'll fill in the only thread
  85          * we're monitoring, the one forked there.
  86          */
  87         err = perf_evlist__create_maps(evlist, &opts.target);
  88         if (err < 0) {
  89                 pr_debug("Not enough memory to create thread/cpu maps\n");
  90                 goto out_delete_evlist;
  91         }
  92
  93         /*
  94          * Prepare the workload in argv[] to run, it'll fork it, and then wait
  95          * for perf_evlist__start_workload() to exec it. This is done this way
  96          * so that we have time to open the evlist (calling sys_perf_event_open
  97          * on all the fds) and then mmap them.
  98          */
  99         err = perf_evlist__prepare_workload(evlist, &opts.target, argv, false, NULL);
 100         if (err < 0) {
 101                 pr_debug("Couldn't run the workload!\n");
 102                 goto out_delete_evlist;
 103         }
 104
 105         /*
 106          * Config the evsels, setting attr->comm on the first one, etc.
 107          */
 108         evsel = evlist__first(evlist);
 109         evsel__set_sample_bit(evsel, CPU);
 110         evsel__set_sample_bit(evsel, TID);
 111         evsel__set_sample_bit(evsel, TIME);
 112         perf_evlist__config(evlist, &opts, NULL);
 113
 114         err = sched__get_first_possible_cpu(evlist->workload.pid, &cpu_mask);
 115         if (err < 0) {
 116                 pr_debug("sched__get_first_possible_cpu: %s\n",
 117                          str_error_r(errno, sbuf, sizeof(sbuf)));
 118                 goto out_delete_evlist;
 119         }
 120
 121         cpu = err;
 122
 123         /*
 124          * So that we can check perf_sample.cpu on all the samples.
 125          */
 126         if (sched_setaffinity(evlist->workload.pid, cpu_mask_size, &cpu_mask) < 0) {
 127                 pr_debug("sched_setaffinity: %s\n",
 128                          str_error_r(errno, sbuf, sizeof(sbuf)));
 129                 goto out_delete_evlist;
 130         }
 131
 132         /*
 133          * Call sys_perf_event_open on all the fds on all the evsels,
 134          * grouping them if asked to.
 135          */
 136         err = evlist__open(evlist);
 137         if (err < 0) {
 138                 pr_debug("perf_evlist__open: %s\n",
 139                          str_error_r(errno, sbuf, sizeof(sbuf)));
 140                 goto out_delete_evlist;
 141         }
 142
 143         /*
 144          * mmap the first fd on a given CPU and ask for events for the other
 145          * fds in the same CPU to be injected in the same mmap ring buffer
 146          * (using ioctl(PERF_EVENT_IOC_SET_OUTPUT)).
 147          */
 148         err = evlist__mmap(evlist, opts.mmap_pages);
 149         if (err < 0) {
 150                 pr_debug("evlist__mmap: %s\n",
 151                          str_error_r(errno, sbuf, sizeof(sbuf)));
 152                 goto out_delete_evlist;
 153         }
 154
 155         /*
 156          * Now that all is properly set up, enable the events, they will
 157          * count just on workload.pid, which will start...
 158          */
 159         evlist__enable(evlist);
 160
 161         /*
 162          * Now!
 163          */
 164         perf_evlist__start_workload(evlist);
 165
 166         while (1) {
 167                 int before = total_events;
 168
 169                 for (i = 0; i < evlist->core.nr_mmaps; i++) {
 170                         union perf_event *event;
 171                         struct mmap *md;
 172
 173                         md = &evlist->mmap[i];
 174                         if (perf_mmap__read_init(&md->core) < 0)
 175                                 continue;
 176
 177                         while ((event = perf_mmap__read_event(&md->core)) != NULL) {
 178                                 const u32 type = event->header.type;
 179                                 const char *name = perf_event__name(type);
 180
 181                                 ++total_events;
 182                                 if (type < PERF_RECORD_MAX)
 183                                         nr_events[type]++;
 184
 185                                 err = perf_evlist__parse_sample(evlist, event, &sample);
 186                                 if (err < 0) {
 187                                         if (verbose > 0)
 188                                                 perf_event__fprintf(event, stderr);
 189                                         pr_debug("Couldn't parse sample\n");
 190                                         goto out_delete_evlist;
 191                                 }
 192
 193                                 if (verbose > 0) {
 194                                         pr_info("%" PRIu64" %d ", sample.time, sample.cpu);
 195                                         perf_event__fprintf(event, stderr);
 196                                 }
 197
 198                                 if (prev_time > sample.time) {
 199                                         pr_debug("%s going backwards in time, prev=%" PRIu64 ", curr=%" PRIu64 "\n",
 200                                                  name, prev_time, sample.time);
 201                                         ++errs;
 202                                 }
 203
 204                                 prev_time = sample.time;
 205
 206                                 if (sample.cpu != cpu) {
 207                                         pr_debug("%s with unexpected cpu, expected %d, got %d\n",
 208                                                  name, cpu, sample.cpu);
 209                                         ++errs;
 210                                 }
 211
 212                                 if ((pid_t)sample.pid != evlist->workload.pid) {
 213                                         pr_debug("%s with unexpected pid, expected %d, got %d\n",
 214                                                  name, evlist->workload.pid, sample.pid);
 215                                         ++errs;
 216                                 }
 217
 218                                 if ((pid_t)sample.tid != evlist->workload.pid) {
 219                                         pr_debug("%s with unexpected tid, expected %d, got %d\n",
 220                                                  name, evlist->workload.pid, sample.tid);
 221                                         ++errs;
 222                                 }
 223
 224                                 if ((type == PERF_RECORD_COMM ||
 225                                      type == PERF_RECORD_MMAP ||
 226                                      type == PERF_RECORD_MMAP2 ||
 227                                      type == PERF_RECORD_FORK ||
 228                                      type == PERF_RECORD_EXIT) &&
 229                                      (pid_t)event->comm.pid != evlist->workload.pid) {
 230                                         pr_debug("%s with unexpected pid/tid\n", name);
 231                                         ++errs;
 232                                 }
 233
 234                                 if ((type == PERF_RECORD_COMM ||
 235                                      type == PERF_RECORD_MMAP ||
 236                                      type == PERF_RECORD_MMAP2) &&
 237                                      event->comm.pid != event->comm.tid) {
 238                                         pr_debug("%s with different pid/tid!\n", name);
 239                                         ++errs;
 240                                 }
 241
 242                                 switch (type) {
 243                                 case PERF_RECORD_COMM:
 244                                         if (strcmp(event->comm.comm, cmd)) {
 245                                                 pr_debug("%s with unexpected comm!\n", name);
 246                                                 ++errs;
 247                                         }
 248                                         break;
 249                                 case PERF_RECORD_EXIT:
 250                                         goto found_exit;
 251                                 case PERF_RECORD_MMAP:
 252                                         mmap_filename = event->mmap.filename;
 253                                         goto check_bname;
 254                                 case PERF_RECORD_MMAP2:
 255                                         mmap_filename = event->mmap2.filename;
 256                                 check_bname:
 257                                         bname = strrchr(mmap_filename, '/');
 258                                         if (bname != NULL) {
 259                                                 if (!found_cmd_mmap)
 260                                                         found_cmd_mmap = !strcmp(bname + 1, cmd);
 261                                                 if (!found_coreutils_mmap)
 262                                                         found_coreutils_mmap = !strcmp(bname + 1, "coreutils");
 263                                                 if (!found_libc_mmap)
 264                                                         found_libc_mmap = !strncmp(bname + 1, "libc", 4);
 265                                                 if (!found_ld_mmap)
 266                                                         found_ld_mmap = !strncmp(bname + 1, "ld", 2);
 267                                         } else if (!found_vdso_mmap)
 268                                                 found_vdso_mmap = !strcmp(mmap_filename, "[vdso]");
 269                                         break;
 270
 271                                 case PERF_RECORD_SAMPLE:
 272                                         /* Just ignore samples for now */
 273                                         break;
 274                                 default:
 275                                         pr_debug("Unexpected perf_event->header.type %d!\n",
 276                                                  type);
 277                                         ++errs;
 278                                 }
 279
 280                                 perf_mmap__consume(&md->core);
 281                         }
 282                         perf_mmap__read_done(&md->core);
 283                 }
 284
 285                 /*
 286                  * We don't use poll here because at least at 3.1 times the
 287                  * PERF_RECORD_{!SAMPLE} events don't honour
 288                  * perf_event_attr.wakeup_events, just PERF_EVENT_SAMPLE does.
 289                  */
 290                 if (total_events == before && false)
 291                         evlist__poll(evlist, -1);
 292
 293                 sleep(1);
 294                 if (++wakeups > 5) {
 295                         pr_debug("No PERF_RECORD_EXIT event!\n");
 296                         break;
 297                 }
 298         }
 299
 300 found_exit:
 301         if (nr_events[PERF_RECORD_COMM] > 1 + !!found_coreutils_mmap) {
 302                 pr_debug("Excessive number of PERF_RECORD_COMM events!\n");
 303                 ++errs;
 304         }
 305
 306         if (nr_events[PERF_RECORD_COMM] == 0) {
 307                 pr_debug("Missing PERF_RECORD_COMM for %s!\n", cmd);
 308                 ++errs;
 309         }
 310
 311         if (!found_cmd_mmap && !found_coreutils_mmap) {
 312                 pr_debug("PERF_RECORD_MMAP for %s missing!\n", cmd);
 313                 ++errs;
 314         }
 315
 316         if (!found_libc_mmap) {
 317                 pr_debug("PERF_RECORD_MMAP for %s missing!\n", "libc");
 318                 ++errs;
 319         }
 320
 321         if (!found_ld_mmap) {
 322                 pr_debug("PERF_RECORD_MMAP for %s missing!\n", "ld");
 323                 ++errs;
 324         }
 325
 326         if (!found_vdso_mmap) {
 327                 pr_debug("PERF_RECORD_MMAP for %s missing!\n", "[vdso]");
 328                 ++errs;
 329         }
 330 out_delete_evlist:
 331         evlist__delete(evlist);
 332 out:
 333         return (err < 0 || errs > 0) ? -1 : 0;
 334 }