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