1 // SPDX-License-Identifier: GPL-2.0 2 #include <sys/time.h> 3 #include <sys/prctl.h> 4 #include <errno.h> 5 #include <time.h> 6 #include <stdlib.h> 7 #include <linux/zalloc.h> 8 #include <perf/cpumap.h> 9 #include <perf/evlist.h> 10 11 #include "parse-events.h" 12 #include "evlist.h" 13 #include "evsel.h" 14 #include "thread_map.h" 15 #include "cpumap.h" 16 #include "tests.h" 17 18 static int spin_sleep(void) 19 { 20 struct timeval start, now, diff, maxtime; 21 struct timespec ts; 22 int err, i; 23 24 maxtime.tv_sec = 0; 25 maxtime.tv_usec = 50000; 26 27 err = gettimeofday(&start, NULL); 28 if (err) 29 return err; 30 31 /* Spin for 50ms */ 32 while (1) { 33 for (i = 0; i < 1000; i++) 34 barrier(); 35 36 err = gettimeofday(&now, NULL); 37 if (err) 38 return err; 39 40 timersub(&now, &start, &diff); 41 if (timercmp(&diff, &maxtime, > /* For checkpatch */)) 42 break; 43 } 44 45 ts.tv_nsec = 50 * 1000 * 1000; 46 ts.tv_sec = 0; 47 48 /* Sleep for 50ms */ 49 err = nanosleep(&ts, NULL); 50 if (err == EINTR) 51 err = 0; 52 53 return err; 54 } 55 56 struct switch_tracking { 57 struct evsel *switch_evsel; 58 struct evsel *cycles_evsel; 59 pid_t *tids; 60 int nr_tids; 61 int comm_seen[4]; 62 int cycles_before_comm_1; 63 int cycles_between_comm_2_and_comm_3; 64 int cycles_after_comm_4; 65 }; 66 67 static int check_comm(struct switch_tracking *switch_tracking, 68 union perf_event *event, const char *comm, int nr) 69 { 70 if (event->header.type == PERF_RECORD_COMM && 71 (pid_t)event->comm.pid == getpid() && 72 (pid_t)event->comm.tid == getpid() && 73 strcmp(event->comm.comm, comm) == 0) { 74 if (switch_tracking->comm_seen[nr]) { 75 pr_debug("Duplicate comm event\n"); 76 return -1; 77 } 78 switch_tracking->comm_seen[nr] = 1; 79 pr_debug3("comm event: %s nr: %d\n", event->comm.comm, nr); 80 return 1; 81 } 82 return 0; 83 } 84 85 static int check_cpu(struct switch_tracking *switch_tracking, int cpu) 86 { 87 int i, nr = cpu + 1; 88 89 if (cpu < 0) 90 return -1; 91 92 if (!switch_tracking->tids) { 93 switch_tracking->tids = calloc(nr, sizeof(pid_t)); 94 if (!switch_tracking->tids) 95 return -1; 96 for (i = 0; i < nr; i++) 97 switch_tracking->tids[i] = -1; 98 switch_tracking->nr_tids = nr; 99 return 0; 100 } 101 102 if (cpu >= switch_tracking->nr_tids) { 103 void *addr; 104 105 addr = realloc(switch_tracking->tids, nr * sizeof(pid_t)); 106 if (!addr) 107 return -1; 108 switch_tracking->tids = addr; 109 for (i = switch_tracking->nr_tids; i < nr; i++) 110 switch_tracking->tids[i] = -1; 111 switch_tracking->nr_tids = nr; 112 return 0; 113 } 114 115 return 0; 116 } 117 118 static int process_sample_event(struct evlist *evlist, 119 union perf_event *event, 120 struct switch_tracking *switch_tracking) 121 { 122 struct perf_sample sample; 123 struct evsel *evsel; 124 pid_t next_tid, prev_tid; 125 int cpu, err; 126 127 if (perf_evlist__parse_sample(evlist, event, &sample)) { 128 pr_debug("perf_evlist__parse_sample failed\n"); 129 return -1; 130 } 131 132 evsel = perf_evlist__id2evsel(evlist, sample.id); 133 if (evsel == switch_tracking->switch_evsel) { 134 next_tid = perf_evsel__intval(evsel, &sample, "next_pid"); 135 prev_tid = perf_evsel__intval(evsel, &sample, "prev_pid"); 136 cpu = sample.cpu; 137 pr_debug3("sched_switch: cpu: %d prev_tid %d next_tid %d\n", 138 cpu, prev_tid, next_tid); 139 err = check_cpu(switch_tracking, cpu); 140 if (err) 141 return err; 142 /* 143 * Check for no missing sched_switch events i.e. that the 144 * evsel->system_wide flag has worked. 145 */ 146 if (switch_tracking->tids[cpu] != -1 && 147 switch_tracking->tids[cpu] != prev_tid) { 148 pr_debug("Missing sched_switch events\n"); 149 return -1; 150 } 151 switch_tracking->tids[cpu] = next_tid; 152 } 153 154 if (evsel == switch_tracking->cycles_evsel) { 155 pr_debug3("cycles event\n"); 156 if (!switch_tracking->comm_seen[0]) 157 switch_tracking->cycles_before_comm_1 = 1; 158 if (switch_tracking->comm_seen[1] && 159 !switch_tracking->comm_seen[2]) 160 switch_tracking->cycles_between_comm_2_and_comm_3 = 1; 161 if (switch_tracking->comm_seen[3]) 162 switch_tracking->cycles_after_comm_4 = 1; 163 } 164 165 return 0; 166 } 167 168 static int process_event(struct evlist *evlist, union perf_event *event, 169 struct switch_tracking *switch_tracking) 170 { 171 if (event->header.type == PERF_RECORD_SAMPLE) 172 return process_sample_event(evlist, event, switch_tracking); 173 174 if (event->header.type == PERF_RECORD_COMM) { 175 int err, done = 0; 176 177 err = check_comm(switch_tracking, event, "Test COMM 1", 0); 178 if (err < 0) 179 return -1; 180 done += err; 181 err = check_comm(switch_tracking, event, "Test COMM 2", 1); 182 if (err < 0) 183 return -1; 184 done += err; 185 err = check_comm(switch_tracking, event, "Test COMM 3", 2); 186 if (err < 0) 187 return -1; 188 done += err; 189 err = check_comm(switch_tracking, event, "Test COMM 4", 3); 190 if (err < 0) 191 return -1; 192 done += err; 193 if (done != 1) { 194 pr_debug("Unexpected comm event\n"); 195 return -1; 196 } 197 } 198 199 return 0; 200 } 201 202 struct event_node { 203 struct list_head list; 204 union perf_event *event; 205 u64 event_time; 206 }; 207 208 static int add_event(struct evlist *evlist, struct list_head *events, 209 union perf_event *event) 210 { 211 struct perf_sample sample; 212 struct event_node *node; 213 214 node = malloc(sizeof(struct event_node)); 215 if (!node) { 216 pr_debug("malloc failed\n"); 217 return -1; 218 } 219 node->event = event; 220 list_add(&node->list, events); 221 222 if (perf_evlist__parse_sample(evlist, event, &sample)) { 223 pr_debug("perf_evlist__parse_sample failed\n"); 224 return -1; 225 } 226 227 if (!sample.time) { 228 pr_debug("event with no time\n"); 229 return -1; 230 } 231 232 node->event_time = sample.time; 233 234 return 0; 235 } 236 237 static void free_event_nodes(struct list_head *events) 238 { 239 struct event_node *node; 240 241 while (!list_empty(events)) { 242 node = list_entry(events->next, struct event_node, list); 243 list_del_init(&node->list); 244 free(node); 245 } 246 } 247 248 static int compar(const void *a, const void *b) 249 { 250 const struct event_node *nodea = a; 251 const struct event_node *nodeb = b; 252 s64 cmp = nodea->event_time - nodeb->event_time; 253 254 return cmp; 255 } 256 257 static int process_events(struct evlist *evlist, 258 struct switch_tracking *switch_tracking) 259 { 260 union perf_event *event; 261 unsigned pos, cnt = 0; 262 LIST_HEAD(events); 263 struct event_node *events_array, *node; 264 struct perf_mmap *md; 265 int i, ret; 266 267 for (i = 0; i < evlist->nr_mmaps; i++) { 268 md = &evlist->mmap[i]; 269 if (perf_mmap__read_init(md) < 0) 270 continue; 271 272 while ((event = perf_mmap__read_event(md)) != NULL) { 273 cnt += 1; 274 ret = add_event(evlist, &events, event); 275 perf_mmap__consume(md); 276 if (ret < 0) 277 goto out_free_nodes; 278 } 279 perf_mmap__read_done(md); 280 } 281 282 events_array = calloc(cnt, sizeof(struct event_node)); 283 if (!events_array) { 284 pr_debug("calloc failed\n"); 285 ret = -1; 286 goto out_free_nodes; 287 } 288 289 pos = 0; 290 list_for_each_entry(node, &events, list) 291 events_array[pos++] = *node; 292 293 qsort(events_array, cnt, sizeof(struct event_node), compar); 294 295 for (pos = 0; pos < cnt; pos++) { 296 ret = process_event(evlist, events_array[pos].event, 297 switch_tracking); 298 if (ret < 0) 299 goto out_free; 300 } 301 302 ret = 0; 303 out_free: 304 pr_debug("%u events recorded\n", cnt); 305 free(events_array); 306 out_free_nodes: 307 free_event_nodes(&events); 308 return ret; 309 } 310 311 /** 312 * test__switch_tracking - test using sched_switch and tracking events. 313 * 314 * This function implements a test that checks that sched_switch events and 315 * tracking events can be recorded for a workload (current process) using the 316 * evsel->system_wide and evsel->tracking flags (respectively) with other events 317 * sometimes enabled or disabled. 318 */ 319 int test__switch_tracking(struct test *test __maybe_unused, int subtest __maybe_unused) 320 { 321 const char *sched_switch = "sched:sched_switch"; 322 struct switch_tracking switch_tracking = { .tids = NULL, }; 323 struct record_opts opts = { 324 .mmap_pages = UINT_MAX, 325 .user_freq = UINT_MAX, 326 .user_interval = ULLONG_MAX, 327 .freq = 4000, 328 .target = { 329 .uses_mmap = true, 330 }, 331 }; 332 struct perf_thread_map *threads = NULL; 333 struct perf_cpu_map *cpus = NULL; 334 struct evlist *evlist = NULL; 335 struct evsel *evsel, *cpu_clocks_evsel, *cycles_evsel; 336 struct evsel *switch_evsel, *tracking_evsel; 337 const char *comm; 338 int err = -1; 339 340 threads = thread_map__new(-1, getpid(), UINT_MAX); 341 if (!threads) { 342 pr_debug("thread_map__new failed!\n"); 343 goto out_err; 344 } 345 346 cpus = perf_cpu_map__new(NULL); 347 if (!cpus) { 348 pr_debug("perf_cpu_map__new failed!\n"); 349 goto out_err; 350 } 351 352 evlist = evlist__new(); 353 if (!evlist) { 354 pr_debug("evlist__new failed!\n"); 355 goto out_err; 356 } 357 358 perf_evlist__set_maps(&evlist->core, cpus, threads); 359 360 /* First event */ 361 err = parse_events(evlist, "cpu-clock:u", NULL); 362 if (err) { 363 pr_debug("Failed to parse event dummy:u\n"); 364 goto out_err; 365 } 366 367 cpu_clocks_evsel = perf_evlist__last(evlist); 368 369 /* Second event */ 370 err = parse_events(evlist, "cycles:u", NULL); 371 if (err) { 372 pr_debug("Failed to parse event cycles:u\n"); 373 goto out_err; 374 } 375 376 cycles_evsel = perf_evlist__last(evlist); 377 378 /* Third event */ 379 if (!perf_evlist__can_select_event(evlist, sched_switch)) { 380 pr_debug("No sched_switch\n"); 381 err = 0; 382 goto out; 383 } 384 385 err = parse_events(evlist, sched_switch, NULL); 386 if (err) { 387 pr_debug("Failed to parse event %s\n", sched_switch); 388 goto out_err; 389 } 390 391 switch_evsel = perf_evlist__last(evlist); 392 393 perf_evsel__set_sample_bit(switch_evsel, CPU); 394 perf_evsel__set_sample_bit(switch_evsel, TIME); 395 396 switch_evsel->system_wide = true; 397 switch_evsel->no_aux_samples = true; 398 switch_evsel->immediate = true; 399 400 /* Test moving an event to the front */ 401 if (cycles_evsel == perf_evlist__first(evlist)) { 402 pr_debug("cycles event already at front"); 403 goto out_err; 404 } 405 perf_evlist__to_front(evlist, cycles_evsel); 406 if (cycles_evsel != perf_evlist__first(evlist)) { 407 pr_debug("Failed to move cycles event to front"); 408 goto out_err; 409 } 410 411 perf_evsel__set_sample_bit(cycles_evsel, CPU); 412 perf_evsel__set_sample_bit(cycles_evsel, TIME); 413 414 /* Fourth event */ 415 err = parse_events(evlist, "dummy:u", NULL); 416 if (err) { 417 pr_debug("Failed to parse event dummy:u\n"); 418 goto out_err; 419 } 420 421 tracking_evsel = perf_evlist__last(evlist); 422 423 perf_evlist__set_tracking_event(evlist, tracking_evsel); 424 425 tracking_evsel->core.attr.freq = 0; 426 tracking_evsel->core.attr.sample_period = 1; 427 428 perf_evsel__set_sample_bit(tracking_evsel, TIME); 429 430 /* Config events */ 431 perf_evlist__config(evlist, &opts, NULL); 432 433 /* Check moved event is still at the front */ 434 if (cycles_evsel != perf_evlist__first(evlist)) { 435 pr_debug("Front event no longer at front"); 436 goto out_err; 437 } 438 439 /* Check tracking event is tracking */ 440 if (!tracking_evsel->core.attr.mmap || !tracking_evsel->core.attr.comm) { 441 pr_debug("Tracking event not tracking\n"); 442 goto out_err; 443 } 444 445 /* Check non-tracking events are not tracking */ 446 evlist__for_each_entry(evlist, evsel) { 447 if (evsel != tracking_evsel) { 448 if (evsel->core.attr.mmap || evsel->core.attr.comm) { 449 pr_debug("Non-tracking event is tracking\n"); 450 goto out_err; 451 } 452 } 453 } 454 455 if (evlist__open(evlist) < 0) { 456 pr_debug("Not supported\n"); 457 err = 0; 458 goto out; 459 } 460 461 err = perf_evlist__mmap(evlist, UINT_MAX); 462 if (err) { 463 pr_debug("perf_evlist__mmap failed!\n"); 464 goto out_err; 465 } 466 467 evlist__enable(evlist); 468 469 err = evsel__disable(cpu_clocks_evsel); 470 if (err) { 471 pr_debug("perf_evlist__disable_event failed!\n"); 472 goto out_err; 473 } 474 475 err = spin_sleep(); 476 if (err) { 477 pr_debug("spin_sleep failed!\n"); 478 goto out_err; 479 } 480 481 comm = "Test COMM 1"; 482 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 483 if (err) { 484 pr_debug("PR_SET_NAME failed!\n"); 485 goto out_err; 486 } 487 488 err = evsel__disable(cycles_evsel); 489 if (err) { 490 pr_debug("perf_evlist__disable_event failed!\n"); 491 goto out_err; 492 } 493 494 comm = "Test COMM 2"; 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 = spin_sleep(); 502 if (err) { 503 pr_debug("spin_sleep failed!\n"); 504 goto out_err; 505 } 506 507 comm = "Test COMM 3"; 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 = evsel__enable(cycles_evsel); 515 if (err) { 516 pr_debug("perf_evlist__disable_event failed!\n"); 517 goto out_err; 518 } 519 520 comm = "Test COMM 4"; 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 = spin_sleep(); 528 if (err) { 529 pr_debug("spin_sleep failed!\n"); 530 goto out_err; 531 } 532 533 evlist__disable(evlist); 534 535 switch_tracking.switch_evsel = switch_evsel; 536 switch_tracking.cycles_evsel = cycles_evsel; 537 538 err = process_events(evlist, &switch_tracking); 539 540 zfree(&switch_tracking.tids); 541 542 if (err) 543 goto out_err; 544 545 /* Check all 4 comm events were seen i.e. that evsel->tracking works */ 546 if (!switch_tracking.comm_seen[0] || !switch_tracking.comm_seen[1] || 547 !switch_tracking.comm_seen[2] || !switch_tracking.comm_seen[3]) { 548 pr_debug("Missing comm events\n"); 549 goto out_err; 550 } 551 552 /* Check cycles event got enabled */ 553 if (!switch_tracking.cycles_before_comm_1) { 554 pr_debug("Missing cycles events\n"); 555 goto out_err; 556 } 557 558 /* Check cycles event got disabled */ 559 if (switch_tracking.cycles_between_comm_2_and_comm_3) { 560 pr_debug("cycles events even though event was disabled\n"); 561 goto out_err; 562 } 563 564 /* Check cycles event got enabled again */ 565 if (!switch_tracking.cycles_after_comm_4) { 566 pr_debug("Missing cycles events\n"); 567 goto out_err; 568 } 569 out: 570 if (evlist) { 571 evlist__disable(evlist); 572 evlist__delete(evlist); 573 } else { 574 perf_cpu_map__put(cpus); 575 perf_thread_map__put(threads); 576 } 577 578 return err; 579 580 out_err: 581 err = -1; 582 goto out; 583 } 584