1 // SPDX-License-Identifier: GPL-2.0 2 #include <perf/evlist.h> 3 #include <perf/evsel.h> 4 #include <linux/bitops.h> 5 #include <linux/list.h> 6 #include <linux/hash.h> 7 #include <sys/ioctl.h> 8 #include <internal/evlist.h> 9 #include <internal/evsel.h> 10 #include <internal/xyarray.h> 11 #include <internal/mmap.h> 12 #include <internal/cpumap.h> 13 #include <internal/threadmap.h> 14 #include <internal/lib.h> 15 #include <linux/zalloc.h> 16 #include <stdlib.h> 17 #include <errno.h> 18 #include <unistd.h> 19 #include <fcntl.h> 20 #include <signal.h> 21 #include <poll.h> 22 #include <sys/mman.h> 23 #include <perf/cpumap.h> 24 #include <perf/threadmap.h> 25 #include <api/fd/array.h> 26 27 void perf_evlist__init(struct perf_evlist *evlist) 28 { 29 int i; 30 31 for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i) 32 INIT_HLIST_HEAD(&evlist->heads[i]); 33 INIT_LIST_HEAD(&evlist->entries); 34 evlist->nr_entries = 0; 35 fdarray__init(&evlist->pollfd, 64); 36 } 37 38 static void __perf_evlist__propagate_maps(struct perf_evlist *evlist, 39 struct perf_evsel *evsel) 40 { 41 /* 42 * We already have cpus for evsel (via PMU sysfs) so 43 * keep it, if there's no target cpu list defined. 44 */ 45 if (!evsel->own_cpus || evlist->has_user_cpus) { 46 perf_cpu_map__put(evsel->cpus); 47 evsel->cpus = perf_cpu_map__get(evlist->cpus); 48 } else if (!evsel->system_wide && perf_cpu_map__empty(evlist->cpus)) { 49 perf_cpu_map__put(evsel->cpus); 50 evsel->cpus = perf_cpu_map__get(evlist->cpus); 51 } else if (evsel->cpus != evsel->own_cpus) { 52 perf_cpu_map__put(evsel->cpus); 53 evsel->cpus = perf_cpu_map__get(evsel->own_cpus); 54 } 55 56 perf_thread_map__put(evsel->threads); 57 evsel->threads = perf_thread_map__get(evlist->threads); 58 evlist->all_cpus = perf_cpu_map__merge(evlist->all_cpus, evsel->cpus); 59 } 60 61 static void perf_evlist__propagate_maps(struct perf_evlist *evlist) 62 { 63 struct perf_evsel *evsel; 64 65 perf_evlist__for_each_evsel(evlist, evsel) 66 __perf_evlist__propagate_maps(evlist, evsel); 67 } 68 69 void perf_evlist__add(struct perf_evlist *evlist, 70 struct perf_evsel *evsel) 71 { 72 list_add_tail(&evsel->node, &evlist->entries); 73 evlist->nr_entries += 1; 74 __perf_evlist__propagate_maps(evlist, evsel); 75 } 76 77 void perf_evlist__remove(struct perf_evlist *evlist, 78 struct perf_evsel *evsel) 79 { 80 list_del_init(&evsel->node); 81 evlist->nr_entries -= 1; 82 } 83 84 struct perf_evlist *perf_evlist__new(void) 85 { 86 struct perf_evlist *evlist = zalloc(sizeof(*evlist)); 87 88 if (evlist != NULL) 89 perf_evlist__init(evlist); 90 91 return evlist; 92 } 93 94 struct perf_evsel * 95 perf_evlist__next(struct perf_evlist *evlist, struct perf_evsel *prev) 96 { 97 struct perf_evsel *next; 98 99 if (!prev) { 100 next = list_first_entry(&evlist->entries, 101 struct perf_evsel, 102 node); 103 } else { 104 next = list_next_entry(prev, node); 105 } 106 107 /* Empty list is noticed here so don't need checking on entry. */ 108 if (&next->node == &evlist->entries) 109 return NULL; 110 111 return next; 112 } 113 114 static void perf_evlist__purge(struct perf_evlist *evlist) 115 { 116 struct perf_evsel *pos, *n; 117 118 perf_evlist__for_each_entry_safe(evlist, n, pos) { 119 list_del_init(&pos->node); 120 perf_evsel__delete(pos); 121 } 122 123 evlist->nr_entries = 0; 124 } 125 126 void perf_evlist__exit(struct perf_evlist *evlist) 127 { 128 perf_cpu_map__put(evlist->cpus); 129 perf_cpu_map__put(evlist->all_cpus); 130 perf_thread_map__put(evlist->threads); 131 evlist->cpus = NULL; 132 evlist->all_cpus = NULL; 133 evlist->threads = NULL; 134 fdarray__exit(&evlist->pollfd); 135 } 136 137 void perf_evlist__delete(struct perf_evlist *evlist) 138 { 139 if (evlist == NULL) 140 return; 141 142 perf_evlist__munmap(evlist); 143 perf_evlist__close(evlist); 144 perf_evlist__purge(evlist); 145 perf_evlist__exit(evlist); 146 free(evlist); 147 } 148 149 void perf_evlist__set_maps(struct perf_evlist *evlist, 150 struct perf_cpu_map *cpus, 151 struct perf_thread_map *threads) 152 { 153 /* 154 * Allow for the possibility that one or another of the maps isn't being 155 * changed i.e. don't put it. Note we are assuming the maps that are 156 * being applied are brand new and evlist is taking ownership of the 157 * original reference count of 1. If that is not the case it is up to 158 * the caller to increase the reference count. 159 */ 160 if (cpus != evlist->cpus) { 161 perf_cpu_map__put(evlist->cpus); 162 evlist->cpus = perf_cpu_map__get(cpus); 163 } 164 165 if (threads != evlist->threads) { 166 perf_thread_map__put(evlist->threads); 167 evlist->threads = perf_thread_map__get(threads); 168 } 169 170 if (!evlist->all_cpus && cpus) 171 evlist->all_cpus = perf_cpu_map__get(cpus); 172 173 perf_evlist__propagate_maps(evlist); 174 } 175 176 int perf_evlist__open(struct perf_evlist *evlist) 177 { 178 struct perf_evsel *evsel; 179 int err; 180 181 perf_evlist__for_each_entry(evlist, evsel) { 182 err = perf_evsel__open(evsel, evsel->cpus, evsel->threads); 183 if (err < 0) 184 goto out_err; 185 } 186 187 return 0; 188 189 out_err: 190 perf_evlist__close(evlist); 191 return err; 192 } 193 194 void perf_evlist__close(struct perf_evlist *evlist) 195 { 196 struct perf_evsel *evsel; 197 198 perf_evlist__for_each_entry_reverse(evlist, evsel) 199 perf_evsel__close(evsel); 200 } 201 202 void perf_evlist__enable(struct perf_evlist *evlist) 203 { 204 struct perf_evsel *evsel; 205 206 perf_evlist__for_each_entry(evlist, evsel) 207 perf_evsel__enable(evsel); 208 } 209 210 void perf_evlist__disable(struct perf_evlist *evlist) 211 { 212 struct perf_evsel *evsel; 213 214 perf_evlist__for_each_entry(evlist, evsel) 215 perf_evsel__disable(evsel); 216 } 217 218 u64 perf_evlist__read_format(struct perf_evlist *evlist) 219 { 220 struct perf_evsel *first = perf_evlist__first(evlist); 221 222 return first->attr.read_format; 223 } 224 225 #define SID(e, x, y) xyarray__entry(e->sample_id, x, y) 226 227 static void perf_evlist__id_hash(struct perf_evlist *evlist, 228 struct perf_evsel *evsel, 229 int cpu, int thread, u64 id) 230 { 231 int hash; 232 struct perf_sample_id *sid = SID(evsel, cpu, thread); 233 234 sid->id = id; 235 sid->evsel = evsel; 236 hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS); 237 hlist_add_head(&sid->node, &evlist->heads[hash]); 238 } 239 240 void perf_evlist__id_add(struct perf_evlist *evlist, 241 struct perf_evsel *evsel, 242 int cpu, int thread, u64 id) 243 { 244 perf_evlist__id_hash(evlist, evsel, cpu, thread, id); 245 evsel->id[evsel->ids++] = id; 246 } 247 248 int perf_evlist__id_add_fd(struct perf_evlist *evlist, 249 struct perf_evsel *evsel, 250 int cpu, int thread, int fd) 251 { 252 u64 read_data[4] = { 0, }; 253 int id_idx = 1; /* The first entry is the counter value */ 254 u64 id; 255 int ret; 256 257 ret = ioctl(fd, PERF_EVENT_IOC_ID, &id); 258 if (!ret) 259 goto add; 260 261 if (errno != ENOTTY) 262 return -1; 263 264 /* Legacy way to get event id.. All hail to old kernels! */ 265 266 /* 267 * This way does not work with group format read, so bail 268 * out in that case. 269 */ 270 if (perf_evlist__read_format(evlist) & PERF_FORMAT_GROUP) 271 return -1; 272 273 if (!(evsel->attr.read_format & PERF_FORMAT_ID) || 274 read(fd, &read_data, sizeof(read_data)) == -1) 275 return -1; 276 277 if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) 278 ++id_idx; 279 if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) 280 ++id_idx; 281 282 id = read_data[id_idx]; 283 284 add: 285 perf_evlist__id_add(evlist, evsel, cpu, thread, id); 286 return 0; 287 } 288 289 int perf_evlist__alloc_pollfd(struct perf_evlist *evlist) 290 { 291 int nr_cpus = perf_cpu_map__nr(evlist->cpus); 292 int nr_threads = perf_thread_map__nr(evlist->threads); 293 int nfds = 0; 294 struct perf_evsel *evsel; 295 296 perf_evlist__for_each_entry(evlist, evsel) { 297 if (evsel->system_wide) 298 nfds += nr_cpus; 299 else 300 nfds += nr_cpus * nr_threads; 301 } 302 303 if (fdarray__available_entries(&evlist->pollfd) < nfds && 304 fdarray__grow(&evlist->pollfd, nfds) < 0) 305 return -ENOMEM; 306 307 return 0; 308 } 309 310 int perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd, 311 void *ptr, short revent, enum fdarray_flags flags) 312 { 313 int pos = fdarray__add(&evlist->pollfd, fd, revent | POLLERR | POLLHUP, flags); 314 315 if (pos >= 0) { 316 evlist->pollfd.priv[pos].ptr = ptr; 317 fcntl(fd, F_SETFL, O_NONBLOCK); 318 } 319 320 return pos; 321 } 322 323 static void perf_evlist__munmap_filtered(struct fdarray *fda, int fd, 324 void *arg __maybe_unused) 325 { 326 struct perf_mmap *map = fda->priv[fd].ptr; 327 328 if (map) 329 perf_mmap__put(map); 330 } 331 332 int perf_evlist__filter_pollfd(struct perf_evlist *evlist, short revents_and_mask) 333 { 334 return fdarray__filter(&evlist->pollfd, revents_and_mask, 335 perf_evlist__munmap_filtered, NULL); 336 } 337 338 int perf_evlist__poll(struct perf_evlist *evlist, int timeout) 339 { 340 return fdarray__poll(&evlist->pollfd, timeout); 341 } 342 343 static struct perf_mmap* perf_evlist__alloc_mmap(struct perf_evlist *evlist, bool overwrite) 344 { 345 int i; 346 struct perf_mmap *map; 347 348 map = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap)); 349 if (!map) 350 return NULL; 351 352 for (i = 0; i < evlist->nr_mmaps; i++) { 353 struct perf_mmap *prev = i ? &map[i - 1] : NULL; 354 355 /* 356 * When the perf_mmap() call is made we grab one refcount, plus 357 * one extra to let perf_mmap__consume() get the last 358 * events after all real references (perf_mmap__get()) are 359 * dropped. 360 * 361 * Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and 362 * thus does perf_mmap__get() on it. 363 */ 364 perf_mmap__init(&map[i], prev, overwrite, NULL); 365 } 366 367 return map; 368 } 369 370 static void perf_evsel__set_sid_idx(struct perf_evsel *evsel, int idx, int cpu, int thread) 371 { 372 struct perf_sample_id *sid = SID(evsel, cpu, thread); 373 374 sid->idx = idx; 375 sid->cpu = perf_cpu_map__cpu(evsel->cpus, cpu); 376 sid->tid = perf_thread_map__pid(evsel->threads, thread); 377 } 378 379 static struct perf_mmap* 380 perf_evlist__mmap_cb_get(struct perf_evlist *evlist, bool overwrite, int idx) 381 { 382 struct perf_mmap *maps; 383 384 maps = overwrite ? evlist->mmap_ovw : evlist->mmap; 385 386 if (!maps) { 387 maps = perf_evlist__alloc_mmap(evlist, overwrite); 388 if (!maps) 389 return NULL; 390 391 if (overwrite) 392 evlist->mmap_ovw = maps; 393 else 394 evlist->mmap = maps; 395 } 396 397 return &maps[idx]; 398 } 399 400 #define FD(e, x, y) (*(int *) xyarray__entry(e->fd, x, y)) 401 402 static int 403 perf_evlist__mmap_cb_mmap(struct perf_mmap *map, struct perf_mmap_param *mp, 404 int output, int cpu) 405 { 406 return perf_mmap__mmap(map, mp, output, cpu); 407 } 408 409 static void perf_evlist__set_mmap_first(struct perf_evlist *evlist, struct perf_mmap *map, 410 bool overwrite) 411 { 412 if (overwrite) 413 evlist->mmap_ovw_first = map; 414 else 415 evlist->mmap_first = map; 416 } 417 418 static int 419 mmap_per_evsel(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops, 420 int idx, struct perf_mmap_param *mp, int cpu_idx, 421 int thread, int *_output, int *_output_overwrite) 422 { 423 int evlist_cpu = perf_cpu_map__cpu(evlist->cpus, cpu_idx); 424 struct perf_evsel *evsel; 425 int revent; 426 427 perf_evlist__for_each_entry(evlist, evsel) { 428 bool overwrite = evsel->attr.write_backward; 429 struct perf_mmap *map; 430 int *output, fd, cpu; 431 432 if (evsel->system_wide && thread) 433 continue; 434 435 cpu = perf_cpu_map__idx(evsel->cpus, evlist_cpu); 436 if (cpu == -1) 437 continue; 438 439 map = ops->get(evlist, overwrite, idx); 440 if (map == NULL) 441 return -ENOMEM; 442 443 if (overwrite) { 444 mp->prot = PROT_READ; 445 output = _output_overwrite; 446 } else { 447 mp->prot = PROT_READ | PROT_WRITE; 448 output = _output; 449 } 450 451 fd = FD(evsel, cpu, thread); 452 453 if (*output == -1) { 454 *output = fd; 455 456 /* 457 * The last one will be done at perf_mmap__consume(), so that we 458 * make sure we don't prevent tools from consuming every last event in 459 * the ring buffer. 460 * 461 * I.e. we can get the POLLHUP meaning that the fd doesn't exist 462 * anymore, but the last events for it are still in the ring buffer, 463 * waiting to be consumed. 464 * 465 * Tools can chose to ignore this at their own discretion, but the 466 * evlist layer can't just drop it when filtering events in 467 * perf_evlist__filter_pollfd(). 468 */ 469 refcount_set(&map->refcnt, 2); 470 471 if (ops->mmap(map, mp, *output, evlist_cpu) < 0) 472 return -1; 473 474 if (!idx) 475 perf_evlist__set_mmap_first(evlist, map, overwrite); 476 } else { 477 if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, *output) != 0) 478 return -1; 479 480 perf_mmap__get(map); 481 } 482 483 revent = !overwrite ? POLLIN : 0; 484 485 if (!evsel->system_wide && 486 perf_evlist__add_pollfd(evlist, fd, map, revent, fdarray_flag__default) < 0) { 487 perf_mmap__put(map); 488 return -1; 489 } 490 491 if (evsel->attr.read_format & PERF_FORMAT_ID) { 492 if (perf_evlist__id_add_fd(evlist, evsel, cpu, thread, 493 fd) < 0) 494 return -1; 495 perf_evsel__set_sid_idx(evsel, idx, cpu, thread); 496 } 497 } 498 499 return 0; 500 } 501 502 static int 503 mmap_per_thread(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops, 504 struct perf_mmap_param *mp) 505 { 506 int thread; 507 int nr_threads = perf_thread_map__nr(evlist->threads); 508 509 for (thread = 0; thread < nr_threads; thread++) { 510 int output = -1; 511 int output_overwrite = -1; 512 513 if (ops->idx) 514 ops->idx(evlist, mp, thread, false); 515 516 if (mmap_per_evsel(evlist, ops, thread, mp, 0, thread, 517 &output, &output_overwrite)) 518 goto out_unmap; 519 } 520 521 return 0; 522 523 out_unmap: 524 perf_evlist__munmap(evlist); 525 return -1; 526 } 527 528 static int 529 mmap_per_cpu(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops, 530 struct perf_mmap_param *mp) 531 { 532 int nr_threads = perf_thread_map__nr(evlist->threads); 533 int nr_cpus = perf_cpu_map__nr(evlist->cpus); 534 int cpu, thread; 535 536 for (cpu = 0; cpu < nr_cpus; cpu++) { 537 int output = -1; 538 int output_overwrite = -1; 539 540 if (ops->idx) 541 ops->idx(evlist, mp, cpu, true); 542 543 for (thread = 0; thread < nr_threads; thread++) { 544 if (mmap_per_evsel(evlist, ops, cpu, mp, cpu, 545 thread, &output, &output_overwrite)) 546 goto out_unmap; 547 } 548 } 549 550 return 0; 551 552 out_unmap: 553 perf_evlist__munmap(evlist); 554 return -1; 555 } 556 557 static int perf_evlist__nr_mmaps(struct perf_evlist *evlist) 558 { 559 int nr_mmaps; 560 561 nr_mmaps = perf_cpu_map__nr(evlist->cpus); 562 if (perf_cpu_map__empty(evlist->cpus)) 563 nr_mmaps = perf_thread_map__nr(evlist->threads); 564 565 return nr_mmaps; 566 } 567 568 int perf_evlist__mmap_ops(struct perf_evlist *evlist, 569 struct perf_evlist_mmap_ops *ops, 570 struct perf_mmap_param *mp) 571 { 572 struct perf_evsel *evsel; 573 const struct perf_cpu_map *cpus = evlist->cpus; 574 const struct perf_thread_map *threads = evlist->threads; 575 576 if (!ops || !ops->get || !ops->mmap) 577 return -EINVAL; 578 579 mp->mask = evlist->mmap_len - page_size - 1; 580 581 evlist->nr_mmaps = perf_evlist__nr_mmaps(evlist); 582 583 perf_evlist__for_each_entry(evlist, evsel) { 584 if ((evsel->attr.read_format & PERF_FORMAT_ID) && 585 evsel->sample_id == NULL && 586 perf_evsel__alloc_id(evsel, perf_cpu_map__nr(cpus), threads->nr) < 0) 587 return -ENOMEM; 588 } 589 590 if (evlist->pollfd.entries == NULL && perf_evlist__alloc_pollfd(evlist) < 0) 591 return -ENOMEM; 592 593 if (perf_cpu_map__empty(cpus)) 594 return mmap_per_thread(evlist, ops, mp); 595 596 return mmap_per_cpu(evlist, ops, mp); 597 } 598 599 int perf_evlist__mmap(struct perf_evlist *evlist, int pages) 600 { 601 struct perf_mmap_param mp; 602 struct perf_evlist_mmap_ops ops = { 603 .get = perf_evlist__mmap_cb_get, 604 .mmap = perf_evlist__mmap_cb_mmap, 605 }; 606 607 evlist->mmap_len = (pages + 1) * page_size; 608 609 return perf_evlist__mmap_ops(evlist, &ops, &mp); 610 } 611 612 void perf_evlist__munmap(struct perf_evlist *evlist) 613 { 614 int i; 615 616 if (evlist->mmap) { 617 for (i = 0; i < evlist->nr_mmaps; i++) 618 perf_mmap__munmap(&evlist->mmap[i]); 619 } 620 621 if (evlist->mmap_ovw) { 622 for (i = 0; i < evlist->nr_mmaps; i++) 623 perf_mmap__munmap(&evlist->mmap_ovw[i]); 624 } 625 626 zfree(&evlist->mmap); 627 zfree(&evlist->mmap_ovw); 628 } 629 630 struct perf_mmap* 631 perf_evlist__next_mmap(struct perf_evlist *evlist, struct perf_mmap *map, 632 bool overwrite) 633 { 634 if (map) 635 return map->next; 636 637 return overwrite ? evlist->mmap_ovw_first : evlist->mmap_first; 638 } 639