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 perf_sample__exit(&sample); 241 return -1; 242 } 243 244 if (!sample.time) { 245 pr_debug("event with no time\n"); 246 perf_sample__exit(&sample); 247 return -1; 248 } 249 250 node->event_time = sample.time; 251 252 perf_sample__exit(&sample); 253 return 0; 254 } 255 256 static void free_event_nodes(struct list_head *events) 257 { 258 struct event_node *node; 259 260 while (!list_empty(events)) { 261 node = list_entry(events->next, struct event_node, list); 262 list_del_init(&node->list); 263 free(node); 264 } 265 } 266 267 static int compar(const void *a, const void *b) 268 { 269 const struct event_node *nodea = a; 270 const struct event_node *nodeb = b; 271 s64 cmp = nodea->event_time - nodeb->event_time; 272 273 return cmp < 0 ? -1 : (cmp > 0 ? 1 : 0); 274 } 275 276 static int process_events(struct evlist *evlist, 277 struct switch_tracking *switch_tracking) 278 { 279 union perf_event *event; 280 unsigned pos, cnt = 0; 281 LIST_HEAD(events); 282 struct event_node *events_array, *node; 283 struct mmap *md; 284 int i, ret; 285 286 for (i = 0; i < evlist__core(evlist)->nr_mmaps; i++) { 287 md = &evlist__mmap(evlist)[i]; 288 if (perf_mmap__read_init(&md->core) < 0) 289 continue; 290 291 while ((event = perf_mmap__read_event(&md->core)) != NULL) { 292 cnt += 1; 293 ret = add_event(evlist, &events, event); 294 perf_mmap__consume(&md->core); 295 if (ret < 0) 296 goto out_free_nodes; 297 } 298 perf_mmap__read_done(&md->core); 299 } 300 301 events_array = calloc(cnt, sizeof(struct event_node)); 302 if (!events_array) { 303 pr_debug("calloc failed\n"); 304 ret = -1; 305 goto out_free_nodes; 306 } 307 308 pos = 0; 309 list_for_each_entry(node, &events, list) 310 events_array[pos++] = *node; 311 312 qsort(events_array, cnt, sizeof(struct event_node), compar); 313 314 for (pos = 0; pos < cnt; pos++) { 315 ret = process_event(evlist, events_array[pos].event, 316 switch_tracking); 317 if (ret < 0) 318 goto out_free; 319 } 320 321 ret = 0; 322 out_free: 323 pr_debug("%u events recorded\n", cnt); 324 free(events_array); 325 out_free_nodes: 326 free_event_nodes(&events); 327 return ret; 328 } 329 330 /** 331 * test__switch_tracking - test using sched_switch and tracking events. 332 * 333 * This function implements a test that checks that sched_switch events and 334 * tracking events can be recorded for a workload (current process) using the 335 * evsel->core.system_wide and evsel->tracking flags (respectively) with other events 336 * sometimes enabled or disabled. 337 */ 338 static int test__switch_tracking(struct test_suite *test __maybe_unused, int subtest __maybe_unused) 339 { 340 const char *sched_switch = "sched:sched_switch"; 341 const char *cycles = "cpu-cycles:u"; 342 struct switch_tracking switch_tracking = { .tids = NULL, }; 343 struct record_opts opts = { 344 .mmap_pages = UINT_MAX, 345 .user_freq = UINT_MAX, 346 .user_interval = ULLONG_MAX, 347 .freq = 4000, 348 .target = { 349 .uses_mmap = true, 350 }, 351 }; 352 struct perf_thread_map *threads = NULL; 353 struct perf_cpu_map *cpus = NULL; 354 struct evlist *evlist = NULL; 355 struct evsel *evsel, *cpu_clocks_evsel, *cycles_evsel; 356 struct evsel *switch_evsel, *tracking_evsel; 357 const char *comm; 358 int err = -1; 359 360 threads = thread_map__new_by_tid(getpid()); 361 if (!threads) { 362 pr_debug("thread_map__new failed!\n"); 363 goto out_err; 364 } 365 366 cpus = perf_cpu_map__new_online_cpus(); 367 if (!cpus) { 368 pr_debug("perf_cpu_map__new failed!\n"); 369 goto out_err; 370 } 371 372 evlist = evlist__new(); 373 if (!evlist) { 374 pr_debug("evlist__new failed!\n"); 375 goto out_err; 376 } 377 378 perf_evlist__set_maps(evlist__core(evlist), cpus, threads); 379 380 /* First event */ 381 err = parse_event(evlist, "cpu-clock:u"); 382 if (err) { 383 pr_debug("Failed to parse event dummy:u\n"); 384 goto out_err; 385 } 386 387 cpu_clocks_evsel = evlist__last(evlist); 388 389 /* Second event */ 390 err = parse_event(evlist, cycles); 391 if (err) { 392 pr_debug("Failed to parse event %s\n", cycles); 393 goto out_err; 394 } 395 396 cycles_evsel = evlist__last(evlist); 397 398 /* Third event */ 399 if (!evlist__can_select_event(evlist, sched_switch)) { 400 pr_debug("No sched_switch\n"); 401 err = 0; 402 goto out; 403 } 404 405 switch_evsel = evlist__add_sched_switch(evlist, true); 406 if (IS_ERR(switch_evsel)) { 407 err = PTR_ERR(switch_evsel); 408 pr_debug("Failed to create event %s\n", sched_switch); 409 goto out_err; 410 } 411 412 switch_evsel->immediate = true; 413 414 /* Test moving an event to the front */ 415 if (cycles_evsel == evlist__first(evlist)) { 416 pr_debug("cycles event already at front"); 417 goto out_err; 418 } 419 evlist__to_front(evlist, cycles_evsel); 420 if (cycles_evsel != evlist__first(evlist)) { 421 pr_debug("Failed to move cycles event to front"); 422 goto out_err; 423 } 424 425 evsel__set_sample_bit(cycles_evsel, CPU); 426 evsel__set_sample_bit(cycles_evsel, TIME); 427 428 /* Fourth event */ 429 err = parse_event(evlist, "dummy:u"); 430 if (err) { 431 pr_debug("Failed to parse event dummy:u\n"); 432 goto out_err; 433 } 434 435 tracking_evsel = evlist__last(evlist); 436 437 evlist__set_tracking_event(evlist, tracking_evsel); 438 439 tracking_evsel->core.attr.freq = 0; 440 tracking_evsel->core.attr.sample_period = 1; 441 442 evsel__set_sample_bit(tracking_evsel, TIME); 443 444 /* Config events */ 445 evlist__config(evlist, &opts, NULL); 446 447 /* Check moved event is still at the front */ 448 if (cycles_evsel != evlist__first(evlist)) { 449 pr_debug("Front event no longer at front"); 450 goto out_err; 451 } 452 453 /* Check tracking event is tracking */ 454 if (!tracking_evsel->core.attr.mmap || !tracking_evsel->core.attr.comm) { 455 pr_debug("Tracking event not tracking\n"); 456 goto out_err; 457 } 458 459 /* Check non-tracking events are not tracking */ 460 evlist__for_each_entry(evlist, evsel) { 461 if (evsel != tracking_evsel) { 462 if (evsel->core.attr.mmap || evsel->core.attr.comm) { 463 pr_debug("Non-tracking event is tracking\n"); 464 goto out_err; 465 } 466 } 467 } 468 469 if (evlist__open(evlist) < 0) { 470 pr_debug("Not supported\n"); 471 err = 0; 472 goto out; 473 } 474 475 err = evlist__do_mmap(evlist, UINT_MAX); 476 if (err) { 477 pr_debug("evlist__mmap failed!\n"); 478 goto out_err; 479 } 480 481 evlist__enable(evlist); 482 483 err = evsel__disable(cpu_clocks_evsel); 484 if (err) { 485 pr_debug("perf_evlist__disable_event failed!\n"); 486 goto out_err; 487 } 488 489 err = spin_sleep(); 490 if (err) { 491 pr_debug("spin_sleep failed!\n"); 492 goto out_err; 493 } 494 495 comm = "Test COMM 1"; 496 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 497 if (err) { 498 pr_debug("PR_SET_NAME failed!\n"); 499 goto out_err; 500 } 501 502 err = evsel__disable(cycles_evsel); 503 if (err) { 504 pr_debug("perf_evlist__disable_event failed!\n"); 505 goto out_err; 506 } 507 508 comm = "Test COMM 2"; 509 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 510 if (err) { 511 pr_debug("PR_SET_NAME failed!\n"); 512 goto out_err; 513 } 514 515 err = spin_sleep(); 516 if (err) { 517 pr_debug("spin_sleep failed!\n"); 518 goto out_err; 519 } 520 521 comm = "Test COMM 3"; 522 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 523 if (err) { 524 pr_debug("PR_SET_NAME failed!\n"); 525 goto out_err; 526 } 527 528 err = evsel__enable(cycles_evsel); 529 if (err) { 530 pr_debug("perf_evlist__disable_event failed!\n"); 531 goto out_err; 532 } 533 534 comm = "Test COMM 4"; 535 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 536 if (err) { 537 pr_debug("PR_SET_NAME failed!\n"); 538 goto out_err; 539 } 540 541 err = spin_sleep(); 542 if (err) { 543 pr_debug("spin_sleep failed!\n"); 544 goto out_err; 545 } 546 547 evlist__disable(evlist); 548 549 switch_tracking.switch_evsel = switch_evsel; 550 switch_tracking.cycles_evsel = cycles_evsel; 551 552 err = process_events(evlist, &switch_tracking); 553 554 zfree(&switch_tracking.tids); 555 556 if (err) 557 goto out_err; 558 559 /* Check all 4 comm events were seen i.e. that evsel->tracking works */ 560 if (!switch_tracking.comm_seen[0] || !switch_tracking.comm_seen[1] || 561 !switch_tracking.comm_seen[2] || !switch_tracking.comm_seen[3]) { 562 pr_debug("Missing comm events\n"); 563 goto out_err; 564 } 565 566 /* Check cycles event got enabled */ 567 if (!switch_tracking.cycles_before_comm_1) { 568 pr_debug("Missing cycles events\n"); 569 goto out_err; 570 } 571 572 /* Check cycles event got disabled */ 573 if (switch_tracking.cycles_between_comm_2_and_comm_3) { 574 pr_debug("cycles events even though event was disabled\n"); 575 goto out_err; 576 } 577 578 /* Check cycles event got enabled again */ 579 if (!switch_tracking.cycles_after_comm_4) { 580 pr_debug("Missing cycles events\n"); 581 goto out_err; 582 } 583 out: 584 if (evlist) { 585 evlist__disable(evlist); 586 evlist__put(evlist); 587 } 588 perf_cpu_map__put(cpus); 589 perf_thread_map__put(threads); 590 591 return err; 592 593 out_err: 594 err = -1; 595 goto out; 596 } 597 598 DEFINE_SUITE_EXCLUSIVE("Track with sched_switch", switch_tracking); 599