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 <linux/err.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 "tests.h" 21 #include "util/mmap.h" 22 #include "util/sample.h" 23 #include "pmus.h" 24 25 static int spin_sleep(void) 26 { 27 struct timeval start, now, diff, maxtime; 28 struct timespec ts; 29 int err, i; 30 31 maxtime.tv_sec = 0; 32 maxtime.tv_usec = 50000; 33 34 err = gettimeofday(&start, NULL); 35 if (err) 36 return err; 37 38 /* Spin for 50ms */ 39 while (1) { 40 for (i = 0; i < 1000; i++) 41 barrier(); 42 43 err = gettimeofday(&now, NULL); 44 if (err) 45 return err; 46 47 timersub(&now, &start, &diff); 48 if (timercmp(&diff, &maxtime, > /* For checkpatch */)) 49 break; 50 } 51 52 ts.tv_nsec = 50 * 1000 * 1000; 53 ts.tv_sec = 0; 54 55 /* Sleep for 50ms */ 56 err = nanosleep(&ts, NULL); 57 if (err == EINTR) 58 err = 0; 59 60 return err; 61 } 62 63 struct switch_tracking { 64 struct evsel *switch_evsel; 65 struct evsel *cycles_evsel; 66 pid_t *tids; 67 int nr_tids; 68 int comm_seen[4]; 69 int cycles_before_comm_1; 70 int cycles_between_comm_2_and_comm_3; 71 int cycles_after_comm_4; 72 }; 73 74 static int check_comm(struct switch_tracking *switch_tracking, 75 union perf_event *event, const char *comm, int nr) 76 { 77 if (event->header.type == PERF_RECORD_COMM && 78 (pid_t)event->comm.pid == getpid() && 79 (pid_t)event->comm.tid == getpid() && 80 strcmp(event->comm.comm, comm) == 0) { 81 if (switch_tracking->comm_seen[nr]) { 82 pr_debug("Duplicate comm event\n"); 83 return -1; 84 } 85 switch_tracking->comm_seen[nr] = 1; 86 pr_debug3("comm event: %s nr: %d\n", event->comm.comm, nr); 87 return 1; 88 } 89 return 0; 90 } 91 92 static int check_cpu(struct switch_tracking *switch_tracking, int cpu) 93 { 94 int i, nr = cpu + 1; 95 96 if (cpu < 0) 97 return -1; 98 99 if (!switch_tracking->tids) { 100 switch_tracking->tids = calloc(nr, sizeof(pid_t)); 101 if (!switch_tracking->tids) 102 return -1; 103 for (i = 0; i < nr; i++) 104 switch_tracking->tids[i] = -1; 105 switch_tracking->nr_tids = nr; 106 return 0; 107 } 108 109 if (cpu >= switch_tracking->nr_tids) { 110 void *addr; 111 112 addr = realloc(switch_tracking->tids, nr * sizeof(pid_t)); 113 if (!addr) 114 return -1; 115 switch_tracking->tids = addr; 116 for (i = switch_tracking->nr_tids; i < nr; i++) 117 switch_tracking->tids[i] = -1; 118 switch_tracking->nr_tids = nr; 119 return 0; 120 } 121 122 return 0; 123 } 124 125 static int process_sample_event(struct evlist *evlist, 126 union perf_event *event, 127 struct switch_tracking *switch_tracking) 128 { 129 struct perf_sample sample; 130 struct evsel *evsel; 131 pid_t next_tid, prev_tid; 132 int cpu, err; 133 134 perf_sample__init(&sample, /*all=*/false); 135 if (evlist__parse_sample(evlist, event, &sample)) { 136 pr_debug("evlist__parse_sample failed\n"); 137 err = -1; 138 goto out; 139 } 140 141 evsel = sample.evsel; 142 if (!evsel) 143 evsel = evlist__id2evsel(evlist, sample.id); 144 145 if (evsel == switch_tracking->switch_evsel) { 146 next_tid = perf_sample__intval(&sample, "next_pid"); 147 prev_tid = perf_sample__intval(&sample, "prev_pid"); 148 cpu = sample.cpu; 149 pr_debug3("sched_switch: cpu: %d prev_tid %d next_tid %d\n", 150 cpu, prev_tid, next_tid); 151 err = check_cpu(switch_tracking, cpu); 152 if (err) 153 goto out; 154 /* 155 * Check for no missing sched_switch events i.e. that the 156 * evsel->core.system_wide flag has worked. 157 */ 158 if (switch_tracking->tids[cpu] != -1 && 159 switch_tracking->tids[cpu] != prev_tid) { 160 pr_debug("Missing sched_switch events\n"); 161 err = -1; 162 goto out; 163 } 164 switch_tracking->tids[cpu] = next_tid; 165 } 166 167 if (evsel == switch_tracking->cycles_evsel) { 168 pr_debug3("cycles event\n"); 169 if (!switch_tracking->comm_seen[0]) 170 switch_tracking->cycles_before_comm_1 = 1; 171 if (switch_tracking->comm_seen[1] && 172 !switch_tracking->comm_seen[2]) 173 switch_tracking->cycles_between_comm_2_and_comm_3 = 1; 174 if (switch_tracking->comm_seen[3]) 175 switch_tracking->cycles_after_comm_4 = 1; 176 } 177 178 err = 0; 179 out: 180 perf_sample__exit(&sample); 181 return err; 182 } 183 184 static int process_event(struct evlist *evlist, union perf_event *event, 185 struct switch_tracking *switch_tracking) 186 { 187 if (event->header.type == PERF_RECORD_SAMPLE) 188 return process_sample_event(evlist, event, switch_tracking); 189 190 if (event->header.type == PERF_RECORD_COMM) { 191 int err, done = 0; 192 193 err = check_comm(switch_tracking, event, "Test COMM 1", 0); 194 if (err < 0) 195 return -1; 196 done += err; 197 err = check_comm(switch_tracking, event, "Test COMM 2", 1); 198 if (err < 0) 199 return -1; 200 done += err; 201 err = check_comm(switch_tracking, event, "Test COMM 3", 2); 202 if (err < 0) 203 return -1; 204 done += err; 205 err = check_comm(switch_tracking, event, "Test COMM 4", 3); 206 if (err < 0) 207 return -1; 208 done += err; 209 if (done != 1) { 210 pr_debug("Unexpected comm event\n"); 211 return -1; 212 } 213 } 214 215 return 0; 216 } 217 218 struct event_node { 219 struct list_head list; 220 union perf_event *event; 221 u64 event_time; 222 }; 223 224 static int add_event(struct evlist *evlist, struct list_head *events, 225 union perf_event *event) 226 { 227 struct perf_sample sample; 228 struct event_node *node; 229 230 node = malloc(sizeof(struct event_node)); 231 if (!node) { 232 pr_debug("malloc failed\n"); 233 return -1; 234 } 235 node->event = event; 236 list_add(&node->list, events); 237 238 if (evlist__parse_sample(evlist, event, &sample)) { 239 pr_debug("evlist__parse_sample failed\n"); 240 return -1; 241 } 242 243 if (!sample.time) { 244 pr_debug("event with no time\n"); 245 perf_sample__exit(&sample); 246 return -1; 247 } 248 249 node->event_time = sample.time; 250 251 perf_sample__exit(&sample); 252 return 0; 253 } 254 255 static void free_event_nodes(struct list_head *events) 256 { 257 struct event_node *node; 258 259 while (!list_empty(events)) { 260 node = list_entry(events->next, struct event_node, list); 261 list_del_init(&node->list); 262 free(node); 263 } 264 } 265 266 static int compar(const void *a, const void *b) 267 { 268 const struct event_node *nodea = a; 269 const struct event_node *nodeb = b; 270 s64 cmp = nodea->event_time - nodeb->event_time; 271 272 return cmp < 0 ? -1 : (cmp > 0 ? 1 : 0); 273 } 274 275 static int process_events(struct evlist *evlist, 276 struct switch_tracking *switch_tracking) 277 { 278 union perf_event *event; 279 unsigned pos, cnt = 0; 280 LIST_HEAD(events); 281 struct event_node *events_array, *node; 282 struct mmap *md; 283 int i, ret; 284 285 for (i = 0; i < evlist->core.nr_mmaps; i++) { 286 md = &evlist->mmap[i]; 287 if (perf_mmap__read_init(&md->core) < 0) 288 continue; 289 290 while ((event = perf_mmap__read_event(&md->core)) != NULL) { 291 cnt += 1; 292 ret = add_event(evlist, &events, event); 293 perf_mmap__consume(&md->core); 294 if (ret < 0) 295 goto out_free_nodes; 296 } 297 perf_mmap__read_done(&md->core); 298 } 299 300 events_array = calloc(cnt, sizeof(struct event_node)); 301 if (!events_array) { 302 pr_debug("calloc failed\n"); 303 ret = -1; 304 goto out_free_nodes; 305 } 306 307 pos = 0; 308 list_for_each_entry(node, &events, list) 309 events_array[pos++] = *node; 310 311 qsort(events_array, cnt, sizeof(struct event_node), compar); 312 313 for (pos = 0; pos < cnt; pos++) { 314 ret = process_event(evlist, events_array[pos].event, 315 switch_tracking); 316 if (ret < 0) 317 goto out_free; 318 } 319 320 ret = 0; 321 out_free: 322 pr_debug("%u events recorded\n", cnt); 323 free(events_array); 324 out_free_nodes: 325 free_event_nodes(&events); 326 return ret; 327 } 328 329 /** 330 * test__switch_tracking - test using sched_switch and tracking events. 331 * 332 * This function implements a test that checks that sched_switch events and 333 * tracking events can be recorded for a workload (current process) using the 334 * evsel->core.system_wide and evsel->tracking flags (respectively) with other events 335 * sometimes enabled or disabled. 336 */ 337 static int test__switch_tracking(struct test_suite *test __maybe_unused, int subtest __maybe_unused) 338 { 339 const char *sched_switch = "sched:sched_switch"; 340 const char *cycles = "cpu-cycles:u"; 341 struct switch_tracking switch_tracking = { .tids = NULL, }; 342 struct record_opts opts = { 343 .mmap_pages = UINT_MAX, 344 .user_freq = UINT_MAX, 345 .user_interval = ULLONG_MAX, 346 .freq = 4000, 347 .target = { 348 .uses_mmap = true, 349 }, 350 }; 351 struct perf_thread_map *threads = NULL; 352 struct perf_cpu_map *cpus = NULL; 353 struct evlist *evlist = NULL; 354 struct evsel *evsel, *cpu_clocks_evsel, *cycles_evsel; 355 struct evsel *switch_evsel, *tracking_evsel; 356 const char *comm; 357 int err = -1; 358 359 threads = thread_map__new_by_tid(getpid()); 360 if (!threads) { 361 pr_debug("thread_map__new failed!\n"); 362 goto out_err; 363 } 364 365 cpus = perf_cpu_map__new_online_cpus(); 366 if (!cpus) { 367 pr_debug("perf_cpu_map__new failed!\n"); 368 goto out_err; 369 } 370 371 evlist = evlist__new(); 372 if (!evlist) { 373 pr_debug("evlist__new failed!\n"); 374 goto out_err; 375 } 376 377 perf_evlist__set_maps(&evlist->core, cpus, threads); 378 379 /* First event */ 380 err = parse_event(evlist, "cpu-clock:u"); 381 if (err) { 382 pr_debug("Failed to parse event dummy:u\n"); 383 goto out_err; 384 } 385 386 cpu_clocks_evsel = evlist__last(evlist); 387 388 /* Second event */ 389 err = parse_event(evlist, cycles); 390 if (err) { 391 pr_debug("Failed to parse event %s\n", cycles); 392 goto out_err; 393 } 394 395 cycles_evsel = evlist__last(evlist); 396 397 /* Third event */ 398 if (!evlist__can_select_event(evlist, sched_switch)) { 399 pr_debug("No sched_switch\n"); 400 err = 0; 401 goto out; 402 } 403 404 switch_evsel = evlist__add_sched_switch(evlist, true); 405 if (IS_ERR(switch_evsel)) { 406 err = PTR_ERR(switch_evsel); 407 pr_debug("Failed to create event %s\n", sched_switch); 408 goto out_err; 409 } 410 411 switch_evsel->immediate = true; 412 413 /* Test moving an event to the front */ 414 if (cycles_evsel == evlist__first(evlist)) { 415 pr_debug("cycles event already at front"); 416 goto out_err; 417 } 418 evlist__to_front(evlist, cycles_evsel); 419 if (cycles_evsel != evlist__first(evlist)) { 420 pr_debug("Failed to move cycles event to front"); 421 goto out_err; 422 } 423 424 evsel__set_sample_bit(cycles_evsel, CPU); 425 evsel__set_sample_bit(cycles_evsel, TIME); 426 427 /* Fourth event */ 428 err = parse_event(evlist, "dummy:u"); 429 if (err) { 430 pr_debug("Failed to parse event dummy:u\n"); 431 goto out_err; 432 } 433 434 tracking_evsel = evlist__last(evlist); 435 436 evlist__set_tracking_event(evlist, tracking_evsel); 437 438 tracking_evsel->core.attr.freq = 0; 439 tracking_evsel->core.attr.sample_period = 1; 440 441 evsel__set_sample_bit(tracking_evsel, TIME); 442 443 /* Config events */ 444 evlist__config(evlist, &opts, NULL); 445 446 /* Check moved event is still at the front */ 447 if (cycles_evsel != evlist__first(evlist)) { 448 pr_debug("Front event no longer at front"); 449 goto out_err; 450 } 451 452 /* Check tracking event is tracking */ 453 if (!tracking_evsel->core.attr.mmap || !tracking_evsel->core.attr.comm) { 454 pr_debug("Tracking event not tracking\n"); 455 goto out_err; 456 } 457 458 /* Check non-tracking events are not tracking */ 459 evlist__for_each_entry(evlist, evsel) { 460 if (evsel != tracking_evsel) { 461 if (evsel->core.attr.mmap || evsel->core.attr.comm) { 462 pr_debug("Non-tracking event is tracking\n"); 463 goto out_err; 464 } 465 } 466 } 467 468 if (evlist__open(evlist) < 0) { 469 pr_debug("Not supported\n"); 470 err = 0; 471 goto out; 472 } 473 474 err = evlist__mmap(evlist, UINT_MAX); 475 if (err) { 476 pr_debug("evlist__mmap failed!\n"); 477 goto out_err; 478 } 479 480 evlist__enable(evlist); 481 482 err = evsel__disable(cpu_clocks_evsel); 483 if (err) { 484 pr_debug("perf_evlist__disable_event failed!\n"); 485 goto out_err; 486 } 487 488 err = spin_sleep(); 489 if (err) { 490 pr_debug("spin_sleep failed!\n"); 491 goto out_err; 492 } 493 494 comm = "Test COMM 1"; 495 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 496 if (err) { 497 pr_debug("PR_SET_NAME failed!\n"); 498 goto out_err; 499 } 500 501 err = evsel__disable(cycles_evsel); 502 if (err) { 503 pr_debug("perf_evlist__disable_event failed!\n"); 504 goto out_err; 505 } 506 507 comm = "Test COMM 2"; 508 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 509 if (err) { 510 pr_debug("PR_SET_NAME failed!\n"); 511 goto out_err; 512 } 513 514 err = spin_sleep(); 515 if (err) { 516 pr_debug("spin_sleep failed!\n"); 517 goto out_err; 518 } 519 520 comm = "Test COMM 3"; 521 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 522 if (err) { 523 pr_debug("PR_SET_NAME failed!\n"); 524 goto out_err; 525 } 526 527 err = evsel__enable(cycles_evsel); 528 if (err) { 529 pr_debug("perf_evlist__disable_event failed!\n"); 530 goto out_err; 531 } 532 533 comm = "Test COMM 4"; 534 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 535 if (err) { 536 pr_debug("PR_SET_NAME failed!\n"); 537 goto out_err; 538 } 539 540 err = spin_sleep(); 541 if (err) { 542 pr_debug("spin_sleep failed!\n"); 543 goto out_err; 544 } 545 546 evlist__disable(evlist); 547 548 switch_tracking.switch_evsel = switch_evsel; 549 switch_tracking.cycles_evsel = cycles_evsel; 550 551 err = process_events(evlist, &switch_tracking); 552 553 zfree(&switch_tracking.tids); 554 555 if (err) 556 goto out_err; 557 558 /* Check all 4 comm events were seen i.e. that evsel->tracking works */ 559 if (!switch_tracking.comm_seen[0] || !switch_tracking.comm_seen[1] || 560 !switch_tracking.comm_seen[2] || !switch_tracking.comm_seen[3]) { 561 pr_debug("Missing comm events\n"); 562 goto out_err; 563 } 564 565 /* Check cycles event got enabled */ 566 if (!switch_tracking.cycles_before_comm_1) { 567 pr_debug("Missing cycles events\n"); 568 goto out_err; 569 } 570 571 /* Check cycles event got disabled */ 572 if (switch_tracking.cycles_between_comm_2_and_comm_3) { 573 pr_debug("cycles events even though event was disabled\n"); 574 goto out_err; 575 } 576 577 /* Check cycles event got enabled again */ 578 if (!switch_tracking.cycles_after_comm_4) { 579 pr_debug("Missing cycles events\n"); 580 goto out_err; 581 } 582 out: 583 if (evlist) { 584 evlist__disable(evlist); 585 evlist__delete(evlist); 586 } 587 perf_cpu_map__put(cpus); 588 perf_thread_map__put(threads); 589 590 return err; 591 592 out_err: 593 err = -1; 594 goto out; 595 } 596 597 DEFINE_SUITE_EXCLUSIVE("Track with sched_switch", switch_tracking); 598