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 12 #include "debug.h" 13 #include "parse-events.h" 14 #include "evlist.h" 15 #include "evsel.h" 16 #include "thread_map.h" 17 #include "record.h" 18 #include "tests.h" 19 #include "util/mmap.h" 20 21 static int spin_sleep(void) 22 { 23 struct timeval start, now, diff, maxtime; 24 struct timespec ts; 25 int err, i; 26 27 maxtime.tv_sec = 0; 28 maxtime.tv_usec = 50000; 29 30 err = gettimeofday(&start, NULL); 31 if (err) 32 return err; 33 34 /* Spin for 50ms */ 35 while (1) { 36 for (i = 0; i < 1000; i++) 37 barrier(); 38 39 err = gettimeofday(&now, NULL); 40 if (err) 41 return err; 42 43 timersub(&now, &start, &diff); 44 if (timercmp(&diff, &maxtime, > /* For checkpatch */)) 45 break; 46 } 47 48 ts.tv_nsec = 50 * 1000 * 1000; 49 ts.tv_sec = 0; 50 51 /* Sleep for 50ms */ 52 err = nanosleep(&ts, NULL); 53 if (err == EINTR) 54 err = 0; 55 56 return err; 57 } 58 59 struct switch_tracking { 60 struct evsel *switch_evsel; 61 struct evsel *cycles_evsel; 62 pid_t *tids; 63 int nr_tids; 64 int comm_seen[4]; 65 int cycles_before_comm_1; 66 int cycles_between_comm_2_and_comm_3; 67 int cycles_after_comm_4; 68 }; 69 70 static int check_comm(struct switch_tracking *switch_tracking, 71 union perf_event *event, const char *comm, int nr) 72 { 73 if (event->header.type == PERF_RECORD_COMM && 74 (pid_t)event->comm.pid == getpid() && 75 (pid_t)event->comm.tid == getpid() && 76 strcmp(event->comm.comm, comm) == 0) { 77 if (switch_tracking->comm_seen[nr]) { 78 pr_debug("Duplicate comm event\n"); 79 return -1; 80 } 81 switch_tracking->comm_seen[nr] = 1; 82 pr_debug3("comm event: %s nr: %d\n", event->comm.comm, nr); 83 return 1; 84 } 85 return 0; 86 } 87 88 static int check_cpu(struct switch_tracking *switch_tracking, int cpu) 89 { 90 int i, nr = cpu + 1; 91 92 if (cpu < 0) 93 return -1; 94 95 if (!switch_tracking->tids) { 96 switch_tracking->tids = calloc(nr, sizeof(pid_t)); 97 if (!switch_tracking->tids) 98 return -1; 99 for (i = 0; i < nr; i++) 100 switch_tracking->tids[i] = -1; 101 switch_tracking->nr_tids = nr; 102 return 0; 103 } 104 105 if (cpu >= switch_tracking->nr_tids) { 106 void *addr; 107 108 addr = realloc(switch_tracking->tids, nr * sizeof(pid_t)); 109 if (!addr) 110 return -1; 111 switch_tracking->tids = addr; 112 for (i = switch_tracking->nr_tids; i < nr; i++) 113 switch_tracking->tids[i] = -1; 114 switch_tracking->nr_tids = nr; 115 return 0; 116 } 117 118 return 0; 119 } 120 121 static int process_sample_event(struct evlist *evlist, 122 union perf_event *event, 123 struct switch_tracking *switch_tracking) 124 { 125 struct perf_sample sample; 126 struct evsel *evsel; 127 pid_t next_tid, prev_tid; 128 int cpu, err; 129 130 if (perf_evlist__parse_sample(evlist, event, &sample)) { 131 pr_debug("perf_evlist__parse_sample failed\n"); 132 return -1; 133 } 134 135 evsel = perf_evlist__id2evsel(evlist, sample.id); 136 if (evsel == switch_tracking->switch_evsel) { 137 next_tid = perf_evsel__intval(evsel, &sample, "next_pid"); 138 prev_tid = perf_evsel__intval(evsel, &sample, "prev_pid"); 139 cpu = sample.cpu; 140 pr_debug3("sched_switch: cpu: %d prev_tid %d next_tid %d\n", 141 cpu, prev_tid, next_tid); 142 err = check_cpu(switch_tracking, cpu); 143 if (err) 144 return err; 145 /* 146 * Check for no missing sched_switch events i.e. that the 147 * evsel->core.system_wide flag has worked. 148 */ 149 if (switch_tracking->tids[cpu] != -1 && 150 switch_tracking->tids[cpu] != prev_tid) { 151 pr_debug("Missing sched_switch events\n"); 152 return -1; 153 } 154 switch_tracking->tids[cpu] = next_tid; 155 } 156 157 if (evsel == switch_tracking->cycles_evsel) { 158 pr_debug3("cycles event\n"); 159 if (!switch_tracking->comm_seen[0]) 160 switch_tracking->cycles_before_comm_1 = 1; 161 if (switch_tracking->comm_seen[1] && 162 !switch_tracking->comm_seen[2]) 163 switch_tracking->cycles_between_comm_2_and_comm_3 = 1; 164 if (switch_tracking->comm_seen[3]) 165 switch_tracking->cycles_after_comm_4 = 1; 166 } 167 168 return 0; 169 } 170 171 static int process_event(struct evlist *evlist, union perf_event *event, 172 struct switch_tracking *switch_tracking) 173 { 174 if (event->header.type == PERF_RECORD_SAMPLE) 175 return process_sample_event(evlist, event, switch_tracking); 176 177 if (event->header.type == PERF_RECORD_COMM) { 178 int err, done = 0; 179 180 err = check_comm(switch_tracking, event, "Test COMM 1", 0); 181 if (err < 0) 182 return -1; 183 done += err; 184 err = check_comm(switch_tracking, event, "Test COMM 2", 1); 185 if (err < 0) 186 return -1; 187 done += err; 188 err = check_comm(switch_tracking, event, "Test COMM 3", 2); 189 if (err < 0) 190 return -1; 191 done += err; 192 err = check_comm(switch_tracking, event, "Test COMM 4", 3); 193 if (err < 0) 194 return -1; 195 done += err; 196 if (done != 1) { 197 pr_debug("Unexpected comm event\n"); 198 return -1; 199 } 200 } 201 202 return 0; 203 } 204 205 struct event_node { 206 struct list_head list; 207 union perf_event *event; 208 u64 event_time; 209 }; 210 211 static int add_event(struct evlist *evlist, struct list_head *events, 212 union perf_event *event) 213 { 214 struct perf_sample sample; 215 struct event_node *node; 216 217 node = malloc(sizeof(struct event_node)); 218 if (!node) { 219 pr_debug("malloc failed\n"); 220 return -1; 221 } 222 node->event = event; 223 list_add(&node->list, events); 224 225 if (perf_evlist__parse_sample(evlist, event, &sample)) { 226 pr_debug("perf_evlist__parse_sample failed\n"); 227 return -1; 228 } 229 230 if (!sample.time) { 231 pr_debug("event with no time\n"); 232 return -1; 233 } 234 235 node->event_time = sample.time; 236 237 return 0; 238 } 239 240 static void free_event_nodes(struct list_head *events) 241 { 242 struct event_node *node; 243 244 while (!list_empty(events)) { 245 node = list_entry(events->next, struct event_node, list); 246 list_del_init(&node->list); 247 free(node); 248 } 249 } 250 251 static int compar(const void *a, const void *b) 252 { 253 const struct event_node *nodea = a; 254 const struct event_node *nodeb = b; 255 s64 cmp = nodea->event_time - nodeb->event_time; 256 257 return cmp; 258 } 259 260 static int process_events(struct evlist *evlist, 261 struct switch_tracking *switch_tracking) 262 { 263 union perf_event *event; 264 unsigned pos, cnt = 0; 265 LIST_HEAD(events); 266 struct event_node *events_array, *node; 267 struct mmap *md; 268 int i, ret; 269 270 for (i = 0; i < evlist->core.nr_mmaps; i++) { 271 md = &evlist->mmap[i]; 272 if (perf_mmap__read_init(md) < 0) 273 continue; 274 275 while ((event = perf_mmap__read_event(md)) != NULL) { 276 cnt += 1; 277 ret = add_event(evlist, &events, event); 278 perf_mmap__consume(md); 279 if (ret < 0) 280 goto out_free_nodes; 281 } 282 perf_mmap__read_done(md); 283 } 284 285 events_array = calloc(cnt, sizeof(struct event_node)); 286 if (!events_array) { 287 pr_debug("calloc failed\n"); 288 ret = -1; 289 goto out_free_nodes; 290 } 291 292 pos = 0; 293 list_for_each_entry(node, &events, list) 294 events_array[pos++] = *node; 295 296 qsort(events_array, cnt, sizeof(struct event_node), compar); 297 298 for (pos = 0; pos < cnt; pos++) { 299 ret = process_event(evlist, events_array[pos].event, 300 switch_tracking); 301 if (ret < 0) 302 goto out_free; 303 } 304 305 ret = 0; 306 out_free: 307 pr_debug("%u events recorded\n", cnt); 308 free(events_array); 309 out_free_nodes: 310 free_event_nodes(&events); 311 return ret; 312 } 313 314 /** 315 * test__switch_tracking - test using sched_switch and tracking events. 316 * 317 * This function implements a test that checks that sched_switch events and 318 * tracking events can be recorded for a workload (current process) using the 319 * evsel->core.system_wide and evsel->tracking flags (respectively) with other events 320 * sometimes enabled or disabled. 321 */ 322 int test__switch_tracking(struct test *test __maybe_unused, int subtest __maybe_unused) 323 { 324 const char *sched_switch = "sched:sched_switch"; 325 struct switch_tracking switch_tracking = { .tids = NULL, }; 326 struct record_opts opts = { 327 .mmap_pages = UINT_MAX, 328 .user_freq = UINT_MAX, 329 .user_interval = ULLONG_MAX, 330 .freq = 4000, 331 .target = { 332 .uses_mmap = true, 333 }, 334 }; 335 struct perf_thread_map *threads = NULL; 336 struct perf_cpu_map *cpus = NULL; 337 struct evlist *evlist = NULL; 338 struct evsel *evsel, *cpu_clocks_evsel, *cycles_evsel; 339 struct evsel *switch_evsel, *tracking_evsel; 340 const char *comm; 341 int err = -1; 342 343 threads = thread_map__new(-1, getpid(), UINT_MAX); 344 if (!threads) { 345 pr_debug("thread_map__new failed!\n"); 346 goto out_err; 347 } 348 349 cpus = perf_cpu_map__new(NULL); 350 if (!cpus) { 351 pr_debug("perf_cpu_map__new failed!\n"); 352 goto out_err; 353 } 354 355 evlist = evlist__new(); 356 if (!evlist) { 357 pr_debug("evlist__new failed!\n"); 358 goto out_err; 359 } 360 361 perf_evlist__set_maps(&evlist->core, cpus, threads); 362 363 /* First event */ 364 err = parse_events(evlist, "cpu-clock:u", NULL); 365 if (err) { 366 pr_debug("Failed to parse event dummy:u\n"); 367 goto out_err; 368 } 369 370 cpu_clocks_evsel = evlist__last(evlist); 371 372 /* Second event */ 373 err = parse_events(evlist, "cycles:u", NULL); 374 if (err) { 375 pr_debug("Failed to parse event cycles:u\n"); 376 goto out_err; 377 } 378 379 cycles_evsel = evlist__last(evlist); 380 381 /* Third event */ 382 if (!perf_evlist__can_select_event(evlist, sched_switch)) { 383 pr_debug("No sched_switch\n"); 384 err = 0; 385 goto out; 386 } 387 388 err = parse_events(evlist, sched_switch, NULL); 389 if (err) { 390 pr_debug("Failed to parse event %s\n", sched_switch); 391 goto out_err; 392 } 393 394 switch_evsel = evlist__last(evlist); 395 396 perf_evsel__set_sample_bit(switch_evsel, CPU); 397 perf_evsel__set_sample_bit(switch_evsel, TIME); 398 399 switch_evsel->core.system_wide = true; 400 switch_evsel->no_aux_samples = true; 401 switch_evsel->immediate = true; 402 403 /* Test moving an event to the front */ 404 if (cycles_evsel == evlist__first(evlist)) { 405 pr_debug("cycles event already at front"); 406 goto out_err; 407 } 408 perf_evlist__to_front(evlist, cycles_evsel); 409 if (cycles_evsel != evlist__first(evlist)) { 410 pr_debug("Failed to move cycles event to front"); 411 goto out_err; 412 } 413 414 perf_evsel__set_sample_bit(cycles_evsel, CPU); 415 perf_evsel__set_sample_bit(cycles_evsel, TIME); 416 417 /* Fourth event */ 418 err = parse_events(evlist, "dummy:u", NULL); 419 if (err) { 420 pr_debug("Failed to parse event dummy:u\n"); 421 goto out_err; 422 } 423 424 tracking_evsel = evlist__last(evlist); 425 426 perf_evlist__set_tracking_event(evlist, tracking_evsel); 427 428 tracking_evsel->core.attr.freq = 0; 429 tracking_evsel->core.attr.sample_period = 1; 430 431 perf_evsel__set_sample_bit(tracking_evsel, TIME); 432 433 /* Config events */ 434 perf_evlist__config(evlist, &opts, NULL); 435 436 /* Check moved event is still at the front */ 437 if (cycles_evsel != evlist__first(evlist)) { 438 pr_debug("Front event no longer at front"); 439 goto out_err; 440 } 441 442 /* Check tracking event is tracking */ 443 if (!tracking_evsel->core.attr.mmap || !tracking_evsel->core.attr.comm) { 444 pr_debug("Tracking event not tracking\n"); 445 goto out_err; 446 } 447 448 /* Check non-tracking events are not tracking */ 449 evlist__for_each_entry(evlist, evsel) { 450 if (evsel != tracking_evsel) { 451 if (evsel->core.attr.mmap || evsel->core.attr.comm) { 452 pr_debug("Non-tracking event is tracking\n"); 453 goto out_err; 454 } 455 } 456 } 457 458 if (evlist__open(evlist) < 0) { 459 pr_debug("Not supported\n"); 460 err = 0; 461 goto out; 462 } 463 464 err = evlist__mmap(evlist, UINT_MAX); 465 if (err) { 466 pr_debug("evlist__mmap failed!\n"); 467 goto out_err; 468 } 469 470 evlist__enable(evlist); 471 472 err = evsel__disable(cpu_clocks_evsel); 473 if (err) { 474 pr_debug("perf_evlist__disable_event failed!\n"); 475 goto out_err; 476 } 477 478 err = spin_sleep(); 479 if (err) { 480 pr_debug("spin_sleep failed!\n"); 481 goto out_err; 482 } 483 484 comm = "Test COMM 1"; 485 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 486 if (err) { 487 pr_debug("PR_SET_NAME failed!\n"); 488 goto out_err; 489 } 490 491 err = evsel__disable(cycles_evsel); 492 if (err) { 493 pr_debug("perf_evlist__disable_event failed!\n"); 494 goto out_err; 495 } 496 497 comm = "Test COMM 2"; 498 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 499 if (err) { 500 pr_debug("PR_SET_NAME failed!\n"); 501 goto out_err; 502 } 503 504 err = spin_sleep(); 505 if (err) { 506 pr_debug("spin_sleep failed!\n"); 507 goto out_err; 508 } 509 510 comm = "Test COMM 3"; 511 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 512 if (err) { 513 pr_debug("PR_SET_NAME failed!\n"); 514 goto out_err; 515 } 516 517 err = evsel__enable(cycles_evsel); 518 if (err) { 519 pr_debug("perf_evlist__disable_event failed!\n"); 520 goto out_err; 521 } 522 523 comm = "Test COMM 4"; 524 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 525 if (err) { 526 pr_debug("PR_SET_NAME failed!\n"); 527 goto out_err; 528 } 529 530 err = spin_sleep(); 531 if (err) { 532 pr_debug("spin_sleep failed!\n"); 533 goto out_err; 534 } 535 536 evlist__disable(evlist); 537 538 switch_tracking.switch_evsel = switch_evsel; 539 switch_tracking.cycles_evsel = cycles_evsel; 540 541 err = process_events(evlist, &switch_tracking); 542 543 zfree(&switch_tracking.tids); 544 545 if (err) 546 goto out_err; 547 548 /* Check all 4 comm events were seen i.e. that evsel->tracking works */ 549 if (!switch_tracking.comm_seen[0] || !switch_tracking.comm_seen[1] || 550 !switch_tracking.comm_seen[2] || !switch_tracking.comm_seen[3]) { 551 pr_debug("Missing comm events\n"); 552 goto out_err; 553 } 554 555 /* Check cycles event got enabled */ 556 if (!switch_tracking.cycles_before_comm_1) { 557 pr_debug("Missing cycles events\n"); 558 goto out_err; 559 } 560 561 /* Check cycles event got disabled */ 562 if (switch_tracking.cycles_between_comm_2_and_comm_3) { 563 pr_debug("cycles events even though event was disabled\n"); 564 goto out_err; 565 } 566 567 /* Check cycles event got enabled again */ 568 if (!switch_tracking.cycles_after_comm_4) { 569 pr_debug("Missing cycles events\n"); 570 goto out_err; 571 } 572 out: 573 if (evlist) { 574 evlist__disable(evlist); 575 evlist__delete(evlist); 576 } else { 577 perf_cpu_map__put(cpus); 578 perf_thread_map__put(threads); 579 } 580 581 return err; 582 583 out_err: 584 err = -1; 585 goto out; 586 } 587