1 // SPDX-License-Identifier: GPL-2.0 2 #include <sys/time.h> 3 #include <sys/prctl.h> 4 #include <errno.h> 5 #include <limits.h> 6 #include <time.h> 7 #include <stdlib.h> 8 #include <linux/zalloc.h> 9 #include <perf/cpumap.h> 10 #include <perf/evlist.h> 11 #include <perf/mmap.h> 12 13 #include "debug.h" 14 #include "parse-events.h" 15 #include "evlist.h" 16 #include "evsel.h" 17 #include "thread_map.h" 18 #include "record.h" 19 #include "tests.h" 20 #include "util/mmap.h" 21 #include "pmu.h" 22 23 static int spin_sleep(void) 24 { 25 struct timeval start, now, diff, maxtime; 26 struct timespec ts; 27 int err, i; 28 29 maxtime.tv_sec = 0; 30 maxtime.tv_usec = 50000; 31 32 err = gettimeofday(&start, NULL); 33 if (err) 34 return err; 35 36 /* Spin for 50ms */ 37 while (1) { 38 for (i = 0; i < 1000; i++) 39 barrier(); 40 41 err = gettimeofday(&now, NULL); 42 if (err) 43 return err; 44 45 timersub(&now, &start, &diff); 46 if (timercmp(&diff, &maxtime, > /* For checkpatch */)) 47 break; 48 } 49 50 ts.tv_nsec = 50 * 1000 * 1000; 51 ts.tv_sec = 0; 52 53 /* Sleep for 50ms */ 54 err = nanosleep(&ts, NULL); 55 if (err == EINTR) 56 err = 0; 57 58 return err; 59 } 60 61 struct switch_tracking { 62 struct evsel *switch_evsel; 63 struct evsel *cycles_evsel; 64 pid_t *tids; 65 int nr_tids; 66 int comm_seen[4]; 67 int cycles_before_comm_1; 68 int cycles_between_comm_2_and_comm_3; 69 int cycles_after_comm_4; 70 }; 71 72 static int check_comm(struct switch_tracking *switch_tracking, 73 union perf_event *event, const char *comm, int nr) 74 { 75 if (event->header.type == PERF_RECORD_COMM && 76 (pid_t)event->comm.pid == getpid() && 77 (pid_t)event->comm.tid == getpid() && 78 strcmp(event->comm.comm, comm) == 0) { 79 if (switch_tracking->comm_seen[nr]) { 80 pr_debug("Duplicate comm event\n"); 81 return -1; 82 } 83 switch_tracking->comm_seen[nr] = 1; 84 pr_debug3("comm event: %s nr: %d\n", event->comm.comm, nr); 85 return 1; 86 } 87 return 0; 88 } 89 90 static int check_cpu(struct switch_tracking *switch_tracking, int cpu) 91 { 92 int i, nr = cpu + 1; 93 94 if (cpu < 0) 95 return -1; 96 97 if (!switch_tracking->tids) { 98 switch_tracking->tids = calloc(nr, sizeof(pid_t)); 99 if (!switch_tracking->tids) 100 return -1; 101 for (i = 0; i < nr; i++) 102 switch_tracking->tids[i] = -1; 103 switch_tracking->nr_tids = nr; 104 return 0; 105 } 106 107 if (cpu >= switch_tracking->nr_tids) { 108 void *addr; 109 110 addr = realloc(switch_tracking->tids, nr * sizeof(pid_t)); 111 if (!addr) 112 return -1; 113 switch_tracking->tids = addr; 114 for (i = switch_tracking->nr_tids; i < nr; i++) 115 switch_tracking->tids[i] = -1; 116 switch_tracking->nr_tids = nr; 117 return 0; 118 } 119 120 return 0; 121 } 122 123 static int process_sample_event(struct evlist *evlist, 124 union perf_event *event, 125 struct switch_tracking *switch_tracking) 126 { 127 struct perf_sample sample; 128 struct evsel *evsel; 129 pid_t next_tid, prev_tid; 130 int cpu, err; 131 132 if (evlist__parse_sample(evlist, event, &sample)) { 133 pr_debug("evlist__parse_sample failed\n"); 134 return -1; 135 } 136 137 evsel = evlist__id2evsel(evlist, sample.id); 138 if (evsel == switch_tracking->switch_evsel) { 139 next_tid = evsel__intval(evsel, &sample, "next_pid"); 140 prev_tid = evsel__intval(evsel, &sample, "prev_pid"); 141 cpu = sample.cpu; 142 pr_debug3("sched_switch: cpu: %d prev_tid %d next_tid %d\n", 143 cpu, prev_tid, next_tid); 144 err = check_cpu(switch_tracking, cpu); 145 if (err) 146 return err; 147 /* 148 * Check for no missing sched_switch events i.e. that the 149 * evsel->core.system_wide flag has worked. 150 */ 151 if (switch_tracking->tids[cpu] != -1 && 152 switch_tracking->tids[cpu] != prev_tid) { 153 pr_debug("Missing sched_switch events\n"); 154 return -1; 155 } 156 switch_tracking->tids[cpu] = next_tid; 157 } 158 159 if (evsel == switch_tracking->cycles_evsel) { 160 pr_debug3("cycles event\n"); 161 if (!switch_tracking->comm_seen[0]) 162 switch_tracking->cycles_before_comm_1 = 1; 163 if (switch_tracking->comm_seen[1] && 164 !switch_tracking->comm_seen[2]) 165 switch_tracking->cycles_between_comm_2_and_comm_3 = 1; 166 if (switch_tracking->comm_seen[3]) 167 switch_tracking->cycles_after_comm_4 = 1; 168 } 169 170 return 0; 171 } 172 173 static int process_event(struct evlist *evlist, union perf_event *event, 174 struct switch_tracking *switch_tracking) 175 { 176 if (event->header.type == PERF_RECORD_SAMPLE) 177 return process_sample_event(evlist, event, switch_tracking); 178 179 if (event->header.type == PERF_RECORD_COMM) { 180 int err, done = 0; 181 182 err = check_comm(switch_tracking, event, "Test COMM 1", 0); 183 if (err < 0) 184 return -1; 185 done += err; 186 err = check_comm(switch_tracking, event, "Test COMM 2", 1); 187 if (err < 0) 188 return -1; 189 done += err; 190 err = check_comm(switch_tracking, event, "Test COMM 3", 2); 191 if (err < 0) 192 return -1; 193 done += err; 194 err = check_comm(switch_tracking, event, "Test COMM 4", 3); 195 if (err < 0) 196 return -1; 197 done += err; 198 if (done != 1) { 199 pr_debug("Unexpected comm event\n"); 200 return -1; 201 } 202 } 203 204 return 0; 205 } 206 207 struct event_node { 208 struct list_head list; 209 union perf_event *event; 210 u64 event_time; 211 }; 212 213 static int add_event(struct evlist *evlist, struct list_head *events, 214 union perf_event *event) 215 { 216 struct perf_sample sample; 217 struct event_node *node; 218 219 node = malloc(sizeof(struct event_node)); 220 if (!node) { 221 pr_debug("malloc failed\n"); 222 return -1; 223 } 224 node->event = event; 225 list_add(&node->list, events); 226 227 if (evlist__parse_sample(evlist, event, &sample)) { 228 pr_debug("evlist__parse_sample failed\n"); 229 return -1; 230 } 231 232 if (!sample.time) { 233 pr_debug("event with no time\n"); 234 return -1; 235 } 236 237 node->event_time = sample.time; 238 239 return 0; 240 } 241 242 static void free_event_nodes(struct list_head *events) 243 { 244 struct event_node *node; 245 246 while (!list_empty(events)) { 247 node = list_entry(events->next, struct event_node, list); 248 list_del_init(&node->list); 249 free(node); 250 } 251 } 252 253 static int compar(const void *a, const void *b) 254 { 255 const struct event_node *nodea = a; 256 const struct event_node *nodeb = b; 257 s64 cmp = nodea->event_time - nodeb->event_time; 258 259 return cmp; 260 } 261 262 static int process_events(struct evlist *evlist, 263 struct switch_tracking *switch_tracking) 264 { 265 union perf_event *event; 266 unsigned pos, cnt = 0; 267 LIST_HEAD(events); 268 struct event_node *events_array, *node; 269 struct mmap *md; 270 int i, ret; 271 272 for (i = 0; i < evlist->core.nr_mmaps; i++) { 273 md = &evlist->mmap[i]; 274 if (perf_mmap__read_init(&md->core) < 0) 275 continue; 276 277 while ((event = perf_mmap__read_event(&md->core)) != NULL) { 278 cnt += 1; 279 ret = add_event(evlist, &events, event); 280 perf_mmap__consume(&md->core); 281 if (ret < 0) 282 goto out_free_nodes; 283 } 284 perf_mmap__read_done(&md->core); 285 } 286 287 events_array = calloc(cnt, sizeof(struct event_node)); 288 if (!events_array) { 289 pr_debug("calloc failed\n"); 290 ret = -1; 291 goto out_free_nodes; 292 } 293 294 pos = 0; 295 list_for_each_entry(node, &events, list) 296 events_array[pos++] = *node; 297 298 qsort(events_array, cnt, sizeof(struct event_node), compar); 299 300 for (pos = 0; pos < cnt; pos++) { 301 ret = process_event(evlist, events_array[pos].event, 302 switch_tracking); 303 if (ret < 0) 304 goto out_free; 305 } 306 307 ret = 0; 308 out_free: 309 pr_debug("%u events recorded\n", cnt); 310 free(events_array); 311 out_free_nodes: 312 free_event_nodes(&events); 313 return ret; 314 } 315 316 /** 317 * test__switch_tracking - test using sched_switch and tracking events. 318 * 319 * This function implements a test that checks that sched_switch events and 320 * tracking events can be recorded for a workload (current process) using the 321 * evsel->core.system_wide and evsel->tracking flags (respectively) with other events 322 * sometimes enabled or disabled. 323 */ 324 static int test__switch_tracking(struct test_suite *test __maybe_unused, int subtest __maybe_unused) 325 { 326 const char *sched_switch = "sched:sched_switch"; 327 struct switch_tracking switch_tracking = { .tids = NULL, }; 328 struct record_opts opts = { 329 .mmap_pages = UINT_MAX, 330 .user_freq = UINT_MAX, 331 .user_interval = ULLONG_MAX, 332 .freq = 4000, 333 .target = { 334 .uses_mmap = true, 335 }, 336 }; 337 struct perf_thread_map *threads = NULL; 338 struct perf_cpu_map *cpus = NULL; 339 struct evlist *evlist = NULL; 340 struct evsel *evsel, *cpu_clocks_evsel, *cycles_evsel; 341 struct evsel *switch_evsel, *tracking_evsel; 342 const char *comm; 343 int err = -1; 344 345 threads = thread_map__new(-1, getpid(), UINT_MAX); 346 if (!threads) { 347 pr_debug("thread_map__new failed!\n"); 348 goto out_err; 349 } 350 351 cpus = perf_cpu_map__new(NULL); 352 if (!cpus) { 353 pr_debug("perf_cpu_map__new failed!\n"); 354 goto out_err; 355 } 356 357 evlist = evlist__new(); 358 if (!evlist) { 359 pr_debug("evlist__new failed!\n"); 360 goto out_err; 361 } 362 363 perf_evlist__set_maps(&evlist->core, cpus, threads); 364 365 /* First event */ 366 err = parse_events(evlist, "cpu-clock:u", NULL); 367 if (err) { 368 pr_debug("Failed to parse event dummy:u\n"); 369 goto out_err; 370 } 371 372 cpu_clocks_evsel = evlist__last(evlist); 373 374 /* Second event */ 375 if (perf_pmu__has_hybrid()) 376 err = parse_events(evlist, "cpu_core/cycles/u", NULL); 377 else 378 err = parse_events(evlist, "cycles:u", NULL); 379 if (err) { 380 pr_debug("Failed to parse event cycles:u\n"); 381 goto out_err; 382 } 383 384 cycles_evsel = evlist__last(evlist); 385 386 /* Third event */ 387 if (!evlist__can_select_event(evlist, sched_switch)) { 388 pr_debug("No sched_switch\n"); 389 err = 0; 390 goto out; 391 } 392 393 err = parse_events(evlist, sched_switch, NULL); 394 if (err) { 395 pr_debug("Failed to parse event %s\n", sched_switch); 396 goto out_err; 397 } 398 399 switch_evsel = evlist__last(evlist); 400 401 evsel__set_sample_bit(switch_evsel, CPU); 402 evsel__set_sample_bit(switch_evsel, TIME); 403 404 switch_evsel->core.system_wide = true; 405 switch_evsel->no_aux_samples = true; 406 switch_evsel->immediate = true; 407 408 /* Test moving an event to the front */ 409 if (cycles_evsel == evlist__first(evlist)) { 410 pr_debug("cycles event already at front"); 411 goto out_err; 412 } 413 evlist__to_front(evlist, cycles_evsel); 414 if (cycles_evsel != evlist__first(evlist)) { 415 pr_debug("Failed to move cycles event to front"); 416 goto out_err; 417 } 418 419 evsel__set_sample_bit(cycles_evsel, CPU); 420 evsel__set_sample_bit(cycles_evsel, TIME); 421 422 /* Fourth event */ 423 err = parse_events(evlist, "dummy:u", NULL); 424 if (err) { 425 pr_debug("Failed to parse event dummy:u\n"); 426 goto out_err; 427 } 428 429 tracking_evsel = evlist__last(evlist); 430 431 evlist__set_tracking_event(evlist, tracking_evsel); 432 433 tracking_evsel->core.attr.freq = 0; 434 tracking_evsel->core.attr.sample_period = 1; 435 436 evsel__set_sample_bit(tracking_evsel, TIME); 437 438 /* Config events */ 439 evlist__config(evlist, &opts, NULL); 440 441 /* Check moved event is still at the front */ 442 if (cycles_evsel != evlist__first(evlist)) { 443 pr_debug("Front event no longer at front"); 444 goto out_err; 445 } 446 447 /* Check tracking event is tracking */ 448 if (!tracking_evsel->core.attr.mmap || !tracking_evsel->core.attr.comm) { 449 pr_debug("Tracking event not tracking\n"); 450 goto out_err; 451 } 452 453 /* Check non-tracking events are not tracking */ 454 evlist__for_each_entry(evlist, evsel) { 455 if (evsel != tracking_evsel) { 456 if (evsel->core.attr.mmap || evsel->core.attr.comm) { 457 pr_debug("Non-tracking event is tracking\n"); 458 goto out_err; 459 } 460 } 461 } 462 463 if (evlist__open(evlist) < 0) { 464 pr_debug("Not supported\n"); 465 err = 0; 466 goto out; 467 } 468 469 err = evlist__mmap(evlist, UINT_MAX); 470 if (err) { 471 pr_debug("evlist__mmap failed!\n"); 472 goto out_err; 473 } 474 475 evlist__enable(evlist); 476 477 err = evsel__disable(cpu_clocks_evsel); 478 if (err) { 479 pr_debug("perf_evlist__disable_event failed!\n"); 480 goto out_err; 481 } 482 483 err = spin_sleep(); 484 if (err) { 485 pr_debug("spin_sleep failed!\n"); 486 goto out_err; 487 } 488 489 comm = "Test COMM 1"; 490 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 491 if (err) { 492 pr_debug("PR_SET_NAME failed!\n"); 493 goto out_err; 494 } 495 496 err = evsel__disable(cycles_evsel); 497 if (err) { 498 pr_debug("perf_evlist__disable_event failed!\n"); 499 goto out_err; 500 } 501 502 comm = "Test COMM 2"; 503 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 504 if (err) { 505 pr_debug("PR_SET_NAME failed!\n"); 506 goto out_err; 507 } 508 509 err = spin_sleep(); 510 if (err) { 511 pr_debug("spin_sleep failed!\n"); 512 goto out_err; 513 } 514 515 comm = "Test COMM 3"; 516 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 517 if (err) { 518 pr_debug("PR_SET_NAME failed!\n"); 519 goto out_err; 520 } 521 522 err = evsel__enable(cycles_evsel); 523 if (err) { 524 pr_debug("perf_evlist__disable_event failed!\n"); 525 goto out_err; 526 } 527 528 comm = "Test COMM 4"; 529 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 530 if (err) { 531 pr_debug("PR_SET_NAME failed!\n"); 532 goto out_err; 533 } 534 535 err = spin_sleep(); 536 if (err) { 537 pr_debug("spin_sleep failed!\n"); 538 goto out_err; 539 } 540 541 evlist__disable(evlist); 542 543 switch_tracking.switch_evsel = switch_evsel; 544 switch_tracking.cycles_evsel = cycles_evsel; 545 546 err = process_events(evlist, &switch_tracking); 547 548 zfree(&switch_tracking.tids); 549 550 if (err) 551 goto out_err; 552 553 /* Check all 4 comm events were seen i.e. that evsel->tracking works */ 554 if (!switch_tracking.comm_seen[0] || !switch_tracking.comm_seen[1] || 555 !switch_tracking.comm_seen[2] || !switch_tracking.comm_seen[3]) { 556 pr_debug("Missing comm events\n"); 557 goto out_err; 558 } 559 560 /* Check cycles event got enabled */ 561 if (!switch_tracking.cycles_before_comm_1) { 562 pr_debug("Missing cycles events\n"); 563 goto out_err; 564 } 565 566 /* Check cycles event got disabled */ 567 if (switch_tracking.cycles_between_comm_2_and_comm_3) { 568 pr_debug("cycles events even though event was disabled\n"); 569 goto out_err; 570 } 571 572 /* Check cycles event got enabled again */ 573 if (!switch_tracking.cycles_after_comm_4) { 574 pr_debug("Missing cycles events\n"); 575 goto out_err; 576 } 577 out: 578 if (evlist) { 579 evlist__disable(evlist); 580 evlist__delete(evlist); 581 } 582 perf_cpu_map__put(cpus); 583 perf_thread_map__put(threads); 584 585 return err; 586 587 out_err: 588 err = -1; 589 goto out; 590 } 591 592 DEFINE_SUITE("Track with sched_switch", switch_tracking); 593