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 "pmu.h" 23 24 static int spin_sleep(void) 25 { 26 struct timeval start, now, diff, maxtime; 27 struct timespec ts; 28 int err, i; 29 30 maxtime.tv_sec = 0; 31 maxtime.tv_usec = 50000; 32 33 err = gettimeofday(&start, NULL); 34 if (err) 35 return err; 36 37 /* Spin for 50ms */ 38 while (1) { 39 for (i = 0; i < 1000; i++) 40 barrier(); 41 42 err = gettimeofday(&now, NULL); 43 if (err) 44 return err; 45 46 timersub(&now, &start, &diff); 47 if (timercmp(&diff, &maxtime, > /* For checkpatch */)) 48 break; 49 } 50 51 ts.tv_nsec = 50 * 1000 * 1000; 52 ts.tv_sec = 0; 53 54 /* Sleep for 50ms */ 55 err = nanosleep(&ts, NULL); 56 if (err == EINTR) 57 err = 0; 58 59 return err; 60 } 61 62 struct switch_tracking { 63 struct evsel *switch_evsel; 64 struct evsel *cycles_evsel; 65 pid_t *tids; 66 int nr_tids; 67 int comm_seen[4]; 68 int cycles_before_comm_1; 69 int cycles_between_comm_2_and_comm_3; 70 int cycles_after_comm_4; 71 }; 72 73 static int check_comm(struct switch_tracking *switch_tracking, 74 union perf_event *event, const char *comm, int nr) 75 { 76 if (event->header.type == PERF_RECORD_COMM && 77 (pid_t)event->comm.pid == getpid() && 78 (pid_t)event->comm.tid == getpid() && 79 strcmp(event->comm.comm, comm) == 0) { 80 if (switch_tracking->comm_seen[nr]) { 81 pr_debug("Duplicate comm event\n"); 82 return -1; 83 } 84 switch_tracking->comm_seen[nr] = 1; 85 pr_debug3("comm event: %s nr: %d\n", event->comm.comm, nr); 86 return 1; 87 } 88 return 0; 89 } 90 91 static int check_cpu(struct switch_tracking *switch_tracking, int cpu) 92 { 93 int i, nr = cpu + 1; 94 95 if (cpu < 0) 96 return -1; 97 98 if (!switch_tracking->tids) { 99 switch_tracking->tids = calloc(nr, sizeof(pid_t)); 100 if (!switch_tracking->tids) 101 return -1; 102 for (i = 0; i < nr; i++) 103 switch_tracking->tids[i] = -1; 104 switch_tracking->nr_tids = nr; 105 return 0; 106 } 107 108 if (cpu >= switch_tracking->nr_tids) { 109 void *addr; 110 111 addr = realloc(switch_tracking->tids, nr * sizeof(pid_t)); 112 if (!addr) 113 return -1; 114 switch_tracking->tids = addr; 115 for (i = switch_tracking->nr_tids; i < nr; i++) 116 switch_tracking->tids[i] = -1; 117 switch_tracking->nr_tids = nr; 118 return 0; 119 } 120 121 return 0; 122 } 123 124 static int process_sample_event(struct evlist *evlist, 125 union perf_event *event, 126 struct switch_tracking *switch_tracking) 127 { 128 struct perf_sample sample; 129 struct evsel *evsel; 130 pid_t next_tid, prev_tid; 131 int cpu, err; 132 133 if (evlist__parse_sample(evlist, event, &sample)) { 134 pr_debug("evlist__parse_sample failed\n"); 135 return -1; 136 } 137 138 evsel = evlist__id2evsel(evlist, sample.id); 139 if (evsel == switch_tracking->switch_evsel) { 140 next_tid = evsel__intval(evsel, &sample, "next_pid"); 141 prev_tid = evsel__intval(evsel, &sample, "prev_pid"); 142 cpu = sample.cpu; 143 pr_debug3("sched_switch: cpu: %d prev_tid %d next_tid %d\n", 144 cpu, prev_tid, next_tid); 145 err = check_cpu(switch_tracking, cpu); 146 if (err) 147 return err; 148 /* 149 * Check for no missing sched_switch events i.e. that the 150 * evsel->core.system_wide flag has worked. 151 */ 152 if (switch_tracking->tids[cpu] != -1 && 153 switch_tracking->tids[cpu] != prev_tid) { 154 pr_debug("Missing sched_switch events\n"); 155 return -1; 156 } 157 switch_tracking->tids[cpu] = next_tid; 158 } 159 160 if (evsel == switch_tracking->cycles_evsel) { 161 pr_debug3("cycles event\n"); 162 if (!switch_tracking->comm_seen[0]) 163 switch_tracking->cycles_before_comm_1 = 1; 164 if (switch_tracking->comm_seen[1] && 165 !switch_tracking->comm_seen[2]) 166 switch_tracking->cycles_between_comm_2_and_comm_3 = 1; 167 if (switch_tracking->comm_seen[3]) 168 switch_tracking->cycles_after_comm_4 = 1; 169 } 170 171 return 0; 172 } 173 174 static int process_event(struct evlist *evlist, union perf_event *event, 175 struct switch_tracking *switch_tracking) 176 { 177 if (event->header.type == PERF_RECORD_SAMPLE) 178 return process_sample_event(evlist, event, switch_tracking); 179 180 if (event->header.type == PERF_RECORD_COMM) { 181 int err, done = 0; 182 183 err = check_comm(switch_tracking, event, "Test COMM 1", 0); 184 if (err < 0) 185 return -1; 186 done += err; 187 err = check_comm(switch_tracking, event, "Test COMM 2", 1); 188 if (err < 0) 189 return -1; 190 done += err; 191 err = check_comm(switch_tracking, event, "Test COMM 3", 2); 192 if (err < 0) 193 return -1; 194 done += err; 195 err = check_comm(switch_tracking, event, "Test COMM 4", 3); 196 if (err < 0) 197 return -1; 198 done += err; 199 if (done != 1) { 200 pr_debug("Unexpected comm event\n"); 201 return -1; 202 } 203 } 204 205 return 0; 206 } 207 208 struct event_node { 209 struct list_head list; 210 union perf_event *event; 211 u64 event_time; 212 }; 213 214 static int add_event(struct evlist *evlist, struct list_head *events, 215 union perf_event *event) 216 { 217 struct perf_sample sample; 218 struct event_node *node; 219 220 node = malloc(sizeof(struct event_node)); 221 if (!node) { 222 pr_debug("malloc failed\n"); 223 return -1; 224 } 225 node->event = event; 226 list_add(&node->list, events); 227 228 if (evlist__parse_sample(evlist, event, &sample)) { 229 pr_debug("evlist__parse_sample failed\n"); 230 return -1; 231 } 232 233 if (!sample.time) { 234 pr_debug("event with no time\n"); 235 return -1; 236 } 237 238 node->event_time = sample.time; 239 240 return 0; 241 } 242 243 static void free_event_nodes(struct list_head *events) 244 { 245 struct event_node *node; 246 247 while (!list_empty(events)) { 248 node = list_entry(events->next, struct event_node, list); 249 list_del_init(&node->list); 250 free(node); 251 } 252 } 253 254 static int compar(const void *a, const void *b) 255 { 256 const struct event_node *nodea = a; 257 const struct event_node *nodeb = b; 258 s64 cmp = nodea->event_time - nodeb->event_time; 259 260 return cmp; 261 } 262 263 static int process_events(struct evlist *evlist, 264 struct switch_tracking *switch_tracking) 265 { 266 union perf_event *event; 267 unsigned pos, cnt = 0; 268 LIST_HEAD(events); 269 struct event_node *events_array, *node; 270 struct mmap *md; 271 int i, ret; 272 273 for (i = 0; i < evlist->core.nr_mmaps; i++) { 274 md = &evlist->mmap[i]; 275 if (perf_mmap__read_init(&md->core) < 0) 276 continue; 277 278 while ((event = perf_mmap__read_event(&md->core)) != NULL) { 279 cnt += 1; 280 ret = add_event(evlist, &events, event); 281 perf_mmap__consume(&md->core); 282 if (ret < 0) 283 goto out_free_nodes; 284 } 285 perf_mmap__read_done(&md->core); 286 } 287 288 events_array = calloc(cnt, sizeof(struct event_node)); 289 if (!events_array) { 290 pr_debug("calloc failed\n"); 291 ret = -1; 292 goto out_free_nodes; 293 } 294 295 pos = 0; 296 list_for_each_entry(node, &events, list) 297 events_array[pos++] = *node; 298 299 qsort(events_array, cnt, sizeof(struct event_node), compar); 300 301 for (pos = 0; pos < cnt; pos++) { 302 ret = process_event(evlist, events_array[pos].event, 303 switch_tracking); 304 if (ret < 0) 305 goto out_free; 306 } 307 308 ret = 0; 309 out_free: 310 pr_debug("%u events recorded\n", cnt); 311 free(events_array); 312 out_free_nodes: 313 free_event_nodes(&events); 314 return ret; 315 } 316 317 /** 318 * test__switch_tracking - test using sched_switch and tracking events. 319 * 320 * This function implements a test that checks that sched_switch events and 321 * tracking events can be recorded for a workload (current process) using the 322 * evsel->core.system_wide and evsel->tracking flags (respectively) with other events 323 * sometimes enabled or disabled. 324 */ 325 static int test__switch_tracking(struct test_suite *test __maybe_unused, int subtest __maybe_unused) 326 { 327 const char *sched_switch = "sched:sched_switch"; 328 const char *cycles = "cycles:u"; 329 struct switch_tracking switch_tracking = { .tids = NULL, }; 330 struct record_opts opts = { 331 .mmap_pages = UINT_MAX, 332 .user_freq = UINT_MAX, 333 .user_interval = ULLONG_MAX, 334 .freq = 4000, 335 .target = { 336 .uses_mmap = true, 337 }, 338 }; 339 struct perf_thread_map *threads = NULL; 340 struct perf_cpu_map *cpus = NULL; 341 struct evlist *evlist = NULL; 342 struct evsel *evsel, *cpu_clocks_evsel, *cycles_evsel; 343 struct evsel *switch_evsel, *tracking_evsel; 344 const char *comm; 345 int err = -1; 346 347 threads = thread_map__new(-1, getpid(), UINT_MAX); 348 if (!threads) { 349 pr_debug("thread_map__new failed!\n"); 350 goto out_err; 351 } 352 353 cpus = perf_cpu_map__new(NULL); 354 if (!cpus) { 355 pr_debug("perf_cpu_map__new failed!\n"); 356 goto out_err; 357 } 358 359 evlist = evlist__new(); 360 if (!evlist) { 361 pr_debug("evlist__new failed!\n"); 362 goto out_err; 363 } 364 365 perf_evlist__set_maps(&evlist->core, cpus, threads); 366 367 /* First event */ 368 err = parse_event(evlist, "cpu-clock:u"); 369 if (err) { 370 pr_debug("Failed to parse event dummy:u\n"); 371 goto out_err; 372 } 373 374 cpu_clocks_evsel = evlist__last(evlist); 375 376 /* Second event */ 377 if (perf_pmu__has_hybrid()) { 378 cycles = "cpu_core/cycles/u"; 379 err = parse_event(evlist, cycles); 380 if (err) { 381 cycles = "cpu_atom/cycles/u"; 382 pr_debug("Trying %s\n", cycles); 383 err = parse_event(evlist, cycles); 384 } 385 } else { 386 err = parse_event(evlist, cycles); 387 } 388 if (err) { 389 pr_debug("Failed to parse event %s\n", cycles); 390 goto out_err; 391 } 392 393 cycles_evsel = evlist__last(evlist); 394 395 /* Third event */ 396 if (!evlist__can_select_event(evlist, sched_switch)) { 397 pr_debug("No sched_switch\n"); 398 err = 0; 399 goto out; 400 } 401 402 switch_evsel = evlist__add_sched_switch(evlist, true); 403 if (IS_ERR(switch_evsel)) { 404 err = PTR_ERR(switch_evsel); 405 pr_debug("Failed to create event %s\n", sched_switch); 406 goto out_err; 407 } 408 409 switch_evsel->immediate = true; 410 411 /* Test moving an event to the front */ 412 if (cycles_evsel == evlist__first(evlist)) { 413 pr_debug("cycles event already at front"); 414 goto out_err; 415 } 416 evlist__to_front(evlist, cycles_evsel); 417 if (cycles_evsel != evlist__first(evlist)) { 418 pr_debug("Failed to move cycles event to front"); 419 goto out_err; 420 } 421 422 evsel__set_sample_bit(cycles_evsel, CPU); 423 evsel__set_sample_bit(cycles_evsel, TIME); 424 425 /* Fourth event */ 426 err = parse_event(evlist, "dummy:u"); 427 if (err) { 428 pr_debug("Failed to parse event dummy:u\n"); 429 goto out_err; 430 } 431 432 tracking_evsel = evlist__last(evlist); 433 434 evlist__set_tracking_event(evlist, tracking_evsel); 435 436 tracking_evsel->core.attr.freq = 0; 437 tracking_evsel->core.attr.sample_period = 1; 438 439 evsel__set_sample_bit(tracking_evsel, TIME); 440 441 /* Config events */ 442 evlist__config(evlist, &opts, NULL); 443 444 /* Check moved event is still at the front */ 445 if (cycles_evsel != evlist__first(evlist)) { 446 pr_debug("Front event no longer at front"); 447 goto out_err; 448 } 449 450 /* Check tracking event is tracking */ 451 if (!tracking_evsel->core.attr.mmap || !tracking_evsel->core.attr.comm) { 452 pr_debug("Tracking event not tracking\n"); 453 goto out_err; 454 } 455 456 /* Check non-tracking events are not tracking */ 457 evlist__for_each_entry(evlist, evsel) { 458 if (evsel != tracking_evsel) { 459 if (evsel->core.attr.mmap || evsel->core.attr.comm) { 460 pr_debug("Non-tracking event is tracking\n"); 461 goto out_err; 462 } 463 } 464 } 465 466 if (evlist__open(evlist) < 0) { 467 pr_debug("Not supported\n"); 468 err = 0; 469 goto out; 470 } 471 472 err = evlist__mmap(evlist, UINT_MAX); 473 if (err) { 474 pr_debug("evlist__mmap failed!\n"); 475 goto out_err; 476 } 477 478 evlist__enable(evlist); 479 480 err = evsel__disable(cpu_clocks_evsel); 481 if (err) { 482 pr_debug("perf_evlist__disable_event failed!\n"); 483 goto out_err; 484 } 485 486 err = spin_sleep(); 487 if (err) { 488 pr_debug("spin_sleep failed!\n"); 489 goto out_err; 490 } 491 492 comm = "Test COMM 1"; 493 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 494 if (err) { 495 pr_debug("PR_SET_NAME failed!\n"); 496 goto out_err; 497 } 498 499 err = evsel__disable(cycles_evsel); 500 if (err) { 501 pr_debug("perf_evlist__disable_event failed!\n"); 502 goto out_err; 503 } 504 505 comm = "Test COMM 2"; 506 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 507 if (err) { 508 pr_debug("PR_SET_NAME failed!\n"); 509 goto out_err; 510 } 511 512 err = spin_sleep(); 513 if (err) { 514 pr_debug("spin_sleep failed!\n"); 515 goto out_err; 516 } 517 518 comm = "Test COMM 3"; 519 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 520 if (err) { 521 pr_debug("PR_SET_NAME failed!\n"); 522 goto out_err; 523 } 524 525 err = evsel__enable(cycles_evsel); 526 if (err) { 527 pr_debug("perf_evlist__disable_event failed!\n"); 528 goto out_err; 529 } 530 531 comm = "Test COMM 4"; 532 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0); 533 if (err) { 534 pr_debug("PR_SET_NAME failed!\n"); 535 goto out_err; 536 } 537 538 err = spin_sleep(); 539 if (err) { 540 pr_debug("spin_sleep failed!\n"); 541 goto out_err; 542 } 543 544 evlist__disable(evlist); 545 546 switch_tracking.switch_evsel = switch_evsel; 547 switch_tracking.cycles_evsel = cycles_evsel; 548 549 err = process_events(evlist, &switch_tracking); 550 551 zfree(&switch_tracking.tids); 552 553 if (err) 554 goto out_err; 555 556 /* Check all 4 comm events were seen i.e. that evsel->tracking works */ 557 if (!switch_tracking.comm_seen[0] || !switch_tracking.comm_seen[1] || 558 !switch_tracking.comm_seen[2] || !switch_tracking.comm_seen[3]) { 559 pr_debug("Missing comm events\n"); 560 goto out_err; 561 } 562 563 /* Check cycles event got enabled */ 564 if (!switch_tracking.cycles_before_comm_1) { 565 pr_debug("Missing cycles events\n"); 566 goto out_err; 567 } 568 569 /* Check cycles event got disabled */ 570 if (switch_tracking.cycles_between_comm_2_and_comm_3) { 571 pr_debug("cycles events even though event was disabled\n"); 572 goto out_err; 573 } 574 575 /* Check cycles event got enabled again */ 576 if (!switch_tracking.cycles_after_comm_4) { 577 pr_debug("Missing cycles events\n"); 578 goto out_err; 579 } 580 out: 581 if (evlist) { 582 evlist__disable(evlist); 583 evlist__delete(evlist); 584 } 585 perf_cpu_map__put(cpus); 586 perf_thread_map__put(threads); 587 588 return err; 589 590 out_err: 591 err = -1; 592 goto out; 593 } 594 595 DEFINE_SUITE("Track with sched_switch", switch_tracking); 596