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