1 #define _FILE_OFFSET_BITS 64 2 3 #include <linux/kernel.h> 4 5 #include <byteswap.h> 6 #include <unistd.h> 7 #include <sys/types.h> 8 #include <sys/mman.h> 9 10 #include "evlist.h" 11 #include "evsel.h" 12 #include "session.h" 13 #include "tool.h" 14 #include "sort.h" 15 #include "util.h" 16 #include "cpumap.h" 17 18 static int perf_session__open(struct perf_session *self, bool force) 19 { 20 struct stat input_stat; 21 22 if (!strcmp(self->filename, "-")) { 23 self->fd_pipe = true; 24 self->fd = STDIN_FILENO; 25 26 if (perf_session__read_header(self, self->fd) < 0) 27 pr_err("incompatible file format (rerun with -v to learn more)"); 28 29 return 0; 30 } 31 32 self->fd = open(self->filename, O_RDONLY); 33 if (self->fd < 0) { 34 int err = errno; 35 36 pr_err("failed to open %s: %s", self->filename, strerror(err)); 37 if (err == ENOENT && !strcmp(self->filename, "perf.data")) 38 pr_err(" (try 'perf record' first)"); 39 pr_err("\n"); 40 return -errno; 41 } 42 43 if (fstat(self->fd, &input_stat) < 0) 44 goto out_close; 45 46 if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) { 47 pr_err("file %s not owned by current user or root\n", 48 self->filename); 49 goto out_close; 50 } 51 52 if (!input_stat.st_size) { 53 pr_info("zero-sized file (%s), nothing to do!\n", 54 self->filename); 55 goto out_close; 56 } 57 58 if (perf_session__read_header(self, self->fd) < 0) { 59 pr_err("incompatible file format (rerun with -v to learn more)"); 60 goto out_close; 61 } 62 63 if (!perf_evlist__valid_sample_type(self->evlist)) { 64 pr_err("non matching sample_type"); 65 goto out_close; 66 } 67 68 if (!perf_evlist__valid_sample_id_all(self->evlist)) { 69 pr_err("non matching sample_id_all"); 70 goto out_close; 71 } 72 73 self->size = input_stat.st_size; 74 return 0; 75 76 out_close: 77 close(self->fd); 78 self->fd = -1; 79 return -1; 80 } 81 82 void perf_session__update_sample_type(struct perf_session *self) 83 { 84 self->sample_type = perf_evlist__sample_type(self->evlist); 85 self->sample_size = __perf_evsel__sample_size(self->sample_type); 86 self->sample_id_all = perf_evlist__sample_id_all(self->evlist); 87 self->id_hdr_size = perf_evlist__id_hdr_size(self->evlist); 88 self->host_machine.id_hdr_size = self->id_hdr_size; 89 } 90 91 int perf_session__create_kernel_maps(struct perf_session *self) 92 { 93 int ret = machine__create_kernel_maps(&self->host_machine); 94 95 if (ret >= 0) 96 ret = machines__create_guest_kernel_maps(&self->machines); 97 return ret; 98 } 99 100 static void perf_session__destroy_kernel_maps(struct perf_session *self) 101 { 102 machine__destroy_kernel_maps(&self->host_machine); 103 machines__destroy_guest_kernel_maps(&self->machines); 104 } 105 106 struct perf_session *perf_session__new(const char *filename, int mode, 107 bool force, bool repipe, 108 struct perf_tool *tool) 109 { 110 struct perf_session *self; 111 struct stat st; 112 size_t len; 113 114 if (!filename || !strlen(filename)) { 115 if (!fstat(STDIN_FILENO, &st) && S_ISFIFO(st.st_mode)) 116 filename = "-"; 117 else 118 filename = "perf.data"; 119 } 120 121 len = strlen(filename); 122 self = zalloc(sizeof(*self) + len); 123 124 if (self == NULL) 125 goto out; 126 127 memcpy(self->filename, filename, len); 128 /* 129 * On 64bit we can mmap the data file in one go. No need for tiny mmap 130 * slices. On 32bit we use 32MB. 131 */ 132 #if BITS_PER_LONG == 64 133 self->mmap_window = ULLONG_MAX; 134 #else 135 self->mmap_window = 32 * 1024 * 1024ULL; 136 #endif 137 self->machines = RB_ROOT; 138 self->repipe = repipe; 139 INIT_LIST_HEAD(&self->ordered_samples.samples); 140 INIT_LIST_HEAD(&self->ordered_samples.sample_cache); 141 INIT_LIST_HEAD(&self->ordered_samples.to_free); 142 machine__init(&self->host_machine, "", HOST_KERNEL_ID); 143 144 if (mode == O_RDONLY) { 145 if (perf_session__open(self, force) < 0) 146 goto out_delete; 147 perf_session__update_sample_type(self); 148 } else if (mode == O_WRONLY) { 149 /* 150 * In O_RDONLY mode this will be performed when reading the 151 * kernel MMAP event, in perf_event__process_mmap(). 152 */ 153 if (perf_session__create_kernel_maps(self) < 0) 154 goto out_delete; 155 } 156 157 if (tool && tool->ordering_requires_timestamps && 158 tool->ordered_samples && !self->sample_id_all) { 159 dump_printf("WARNING: No sample_id_all support, falling back to unordered processing\n"); 160 tool->ordered_samples = false; 161 } 162 163 out: 164 return self; 165 out_delete: 166 perf_session__delete(self); 167 return NULL; 168 } 169 170 static void machine__delete_dead_threads(struct machine *machine) 171 { 172 struct thread *n, *t; 173 174 list_for_each_entry_safe(t, n, &machine->dead_threads, node) { 175 list_del(&t->node); 176 thread__delete(t); 177 } 178 } 179 180 static void perf_session__delete_dead_threads(struct perf_session *session) 181 { 182 machine__delete_dead_threads(&session->host_machine); 183 } 184 185 static void machine__delete_threads(struct machine *self) 186 { 187 struct rb_node *nd = rb_first(&self->threads); 188 189 while (nd) { 190 struct thread *t = rb_entry(nd, struct thread, rb_node); 191 192 rb_erase(&t->rb_node, &self->threads); 193 nd = rb_next(nd); 194 thread__delete(t); 195 } 196 } 197 198 static void perf_session__delete_threads(struct perf_session *session) 199 { 200 machine__delete_threads(&session->host_machine); 201 } 202 203 void perf_session__delete(struct perf_session *self) 204 { 205 perf_session__destroy_kernel_maps(self); 206 perf_session__delete_dead_threads(self); 207 perf_session__delete_threads(self); 208 machine__exit(&self->host_machine); 209 close(self->fd); 210 free(self); 211 } 212 213 void machine__remove_thread(struct machine *self, struct thread *th) 214 { 215 self->last_match = NULL; 216 rb_erase(&th->rb_node, &self->threads); 217 /* 218 * We may have references to this thread, for instance in some hist_entry 219 * instances, so just move them to a separate list. 220 */ 221 list_add_tail(&th->node, &self->dead_threads); 222 } 223 224 static bool symbol__match_parent_regex(struct symbol *sym) 225 { 226 if (sym->name && !regexec(&parent_regex, sym->name, 0, NULL, 0)) 227 return 1; 228 229 return 0; 230 } 231 232 static const u8 cpumodes[] = { 233 PERF_RECORD_MISC_USER, 234 PERF_RECORD_MISC_KERNEL, 235 PERF_RECORD_MISC_GUEST_USER, 236 PERF_RECORD_MISC_GUEST_KERNEL 237 }; 238 #define NCPUMODES (sizeof(cpumodes)/sizeof(u8)) 239 240 static void ip__resolve_ams(struct machine *self, struct thread *thread, 241 struct addr_map_symbol *ams, 242 u64 ip) 243 { 244 struct addr_location al; 245 size_t i; 246 u8 m; 247 248 memset(&al, 0, sizeof(al)); 249 250 for (i = 0; i < NCPUMODES; i++) { 251 m = cpumodes[i]; 252 /* 253 * We cannot use the header.misc hint to determine whether a 254 * branch stack address is user, kernel, guest, hypervisor. 255 * Branches may straddle the kernel/user/hypervisor boundaries. 256 * Thus, we have to try consecutively until we find a match 257 * or else, the symbol is unknown 258 */ 259 thread__find_addr_location(thread, self, m, MAP__FUNCTION, 260 ip, &al, NULL); 261 if (al.sym) 262 goto found; 263 } 264 found: 265 ams->addr = ip; 266 ams->al_addr = al.addr; 267 ams->sym = al.sym; 268 ams->map = al.map; 269 } 270 271 struct branch_info *machine__resolve_bstack(struct machine *self, 272 struct thread *thr, 273 struct branch_stack *bs) 274 { 275 struct branch_info *bi; 276 unsigned int i; 277 278 bi = calloc(bs->nr, sizeof(struct branch_info)); 279 if (!bi) 280 return NULL; 281 282 for (i = 0; i < bs->nr; i++) { 283 ip__resolve_ams(self, thr, &bi[i].to, bs->entries[i].to); 284 ip__resolve_ams(self, thr, &bi[i].from, bs->entries[i].from); 285 bi[i].flags = bs->entries[i].flags; 286 } 287 return bi; 288 } 289 290 int machine__resolve_callchain(struct machine *self, struct perf_evsel *evsel, 291 struct thread *thread, 292 struct ip_callchain *chain, 293 struct symbol **parent) 294 { 295 u8 cpumode = PERF_RECORD_MISC_USER; 296 unsigned int i; 297 int err; 298 299 callchain_cursor_reset(&evsel->hists.callchain_cursor); 300 301 for (i = 0; i < chain->nr; i++) { 302 u64 ip; 303 struct addr_location al; 304 305 if (callchain_param.order == ORDER_CALLEE) 306 ip = chain->ips[i]; 307 else 308 ip = chain->ips[chain->nr - i - 1]; 309 310 if (ip >= PERF_CONTEXT_MAX) { 311 switch (ip) { 312 case PERF_CONTEXT_HV: 313 cpumode = PERF_RECORD_MISC_HYPERVISOR; break; 314 case PERF_CONTEXT_KERNEL: 315 cpumode = PERF_RECORD_MISC_KERNEL; break; 316 case PERF_CONTEXT_USER: 317 cpumode = PERF_RECORD_MISC_USER; break; 318 default: 319 break; 320 } 321 continue; 322 } 323 324 al.filtered = false; 325 thread__find_addr_location(thread, self, cpumode, 326 MAP__FUNCTION, ip, &al, NULL); 327 if (al.sym != NULL) { 328 if (sort__has_parent && !*parent && 329 symbol__match_parent_regex(al.sym)) 330 *parent = al.sym; 331 if (!symbol_conf.use_callchain) 332 break; 333 } 334 335 err = callchain_cursor_append(&evsel->hists.callchain_cursor, 336 ip, al.map, al.sym); 337 if (err) 338 return err; 339 } 340 341 return 0; 342 } 343 344 static int process_event_synth_tracing_data_stub(union perf_event *event __used, 345 struct perf_session *session __used) 346 { 347 dump_printf(": unhandled!\n"); 348 return 0; 349 } 350 351 static int process_event_synth_attr_stub(union perf_event *event __used, 352 struct perf_evlist **pevlist __used) 353 { 354 dump_printf(": unhandled!\n"); 355 return 0; 356 } 357 358 static int process_event_sample_stub(struct perf_tool *tool __used, 359 union perf_event *event __used, 360 struct perf_sample *sample __used, 361 struct perf_evsel *evsel __used, 362 struct machine *machine __used) 363 { 364 dump_printf(": unhandled!\n"); 365 return 0; 366 } 367 368 static int process_event_stub(struct perf_tool *tool __used, 369 union perf_event *event __used, 370 struct perf_sample *sample __used, 371 struct machine *machine __used) 372 { 373 dump_printf(": unhandled!\n"); 374 return 0; 375 } 376 377 static int process_finished_round_stub(struct perf_tool *tool __used, 378 union perf_event *event __used, 379 struct perf_session *perf_session __used) 380 { 381 dump_printf(": unhandled!\n"); 382 return 0; 383 } 384 385 static int process_event_type_stub(struct perf_tool *tool __used, 386 union perf_event *event __used) 387 { 388 dump_printf(": unhandled!\n"); 389 return 0; 390 } 391 392 static int process_finished_round(struct perf_tool *tool, 393 union perf_event *event, 394 struct perf_session *session); 395 396 static void perf_tool__fill_defaults(struct perf_tool *tool) 397 { 398 if (tool->sample == NULL) 399 tool->sample = process_event_sample_stub; 400 if (tool->mmap == NULL) 401 tool->mmap = process_event_stub; 402 if (tool->comm == NULL) 403 tool->comm = process_event_stub; 404 if (tool->fork == NULL) 405 tool->fork = process_event_stub; 406 if (tool->exit == NULL) 407 tool->exit = process_event_stub; 408 if (tool->lost == NULL) 409 tool->lost = perf_event__process_lost; 410 if (tool->read == NULL) 411 tool->read = process_event_sample_stub; 412 if (tool->throttle == NULL) 413 tool->throttle = process_event_stub; 414 if (tool->unthrottle == NULL) 415 tool->unthrottle = process_event_stub; 416 if (tool->attr == NULL) 417 tool->attr = process_event_synth_attr_stub; 418 if (tool->event_type == NULL) 419 tool->event_type = process_event_type_stub; 420 if (tool->tracing_data == NULL) 421 tool->tracing_data = process_event_synth_tracing_data_stub; 422 if (tool->build_id == NULL) 423 tool->build_id = process_finished_round_stub; 424 if (tool->finished_round == NULL) { 425 if (tool->ordered_samples) 426 tool->finished_round = process_finished_round; 427 else 428 tool->finished_round = process_finished_round_stub; 429 } 430 } 431 432 void mem_bswap_64(void *src, int byte_size) 433 { 434 u64 *m = src; 435 436 while (byte_size > 0) { 437 *m = bswap_64(*m); 438 byte_size -= sizeof(u64); 439 ++m; 440 } 441 } 442 443 static void perf_event__all64_swap(union perf_event *event) 444 { 445 struct perf_event_header *hdr = &event->header; 446 mem_bswap_64(hdr + 1, event->header.size - sizeof(*hdr)); 447 } 448 449 static void perf_event__comm_swap(union perf_event *event) 450 { 451 event->comm.pid = bswap_32(event->comm.pid); 452 event->comm.tid = bswap_32(event->comm.tid); 453 } 454 455 static void perf_event__mmap_swap(union perf_event *event) 456 { 457 event->mmap.pid = bswap_32(event->mmap.pid); 458 event->mmap.tid = bswap_32(event->mmap.tid); 459 event->mmap.start = bswap_64(event->mmap.start); 460 event->mmap.len = bswap_64(event->mmap.len); 461 event->mmap.pgoff = bswap_64(event->mmap.pgoff); 462 } 463 464 static void perf_event__task_swap(union perf_event *event) 465 { 466 event->fork.pid = bswap_32(event->fork.pid); 467 event->fork.tid = bswap_32(event->fork.tid); 468 event->fork.ppid = bswap_32(event->fork.ppid); 469 event->fork.ptid = bswap_32(event->fork.ptid); 470 event->fork.time = bswap_64(event->fork.time); 471 } 472 473 static void perf_event__read_swap(union perf_event *event) 474 { 475 event->read.pid = bswap_32(event->read.pid); 476 event->read.tid = bswap_32(event->read.tid); 477 event->read.value = bswap_64(event->read.value); 478 event->read.time_enabled = bswap_64(event->read.time_enabled); 479 event->read.time_running = bswap_64(event->read.time_running); 480 event->read.id = bswap_64(event->read.id); 481 } 482 483 /* exported for swapping attributes in file header */ 484 void perf_event__attr_swap(struct perf_event_attr *attr) 485 { 486 attr->type = bswap_32(attr->type); 487 attr->size = bswap_32(attr->size); 488 attr->config = bswap_64(attr->config); 489 attr->sample_period = bswap_64(attr->sample_period); 490 attr->sample_type = bswap_64(attr->sample_type); 491 attr->read_format = bswap_64(attr->read_format); 492 attr->wakeup_events = bswap_32(attr->wakeup_events); 493 attr->bp_type = bswap_32(attr->bp_type); 494 attr->bp_addr = bswap_64(attr->bp_addr); 495 attr->bp_len = bswap_64(attr->bp_len); 496 } 497 498 static void perf_event__hdr_attr_swap(union perf_event *event) 499 { 500 size_t size; 501 502 perf_event__attr_swap(&event->attr.attr); 503 504 size = event->header.size; 505 size -= (void *)&event->attr.id - (void *)event; 506 mem_bswap_64(event->attr.id, size); 507 } 508 509 static void perf_event__event_type_swap(union perf_event *event) 510 { 511 event->event_type.event_type.event_id = 512 bswap_64(event->event_type.event_type.event_id); 513 } 514 515 static void perf_event__tracing_data_swap(union perf_event *event) 516 { 517 event->tracing_data.size = bswap_32(event->tracing_data.size); 518 } 519 520 typedef void (*perf_event__swap_op)(union perf_event *event); 521 522 static perf_event__swap_op perf_event__swap_ops[] = { 523 [PERF_RECORD_MMAP] = perf_event__mmap_swap, 524 [PERF_RECORD_COMM] = perf_event__comm_swap, 525 [PERF_RECORD_FORK] = perf_event__task_swap, 526 [PERF_RECORD_EXIT] = perf_event__task_swap, 527 [PERF_RECORD_LOST] = perf_event__all64_swap, 528 [PERF_RECORD_READ] = perf_event__read_swap, 529 [PERF_RECORD_SAMPLE] = perf_event__all64_swap, 530 [PERF_RECORD_HEADER_ATTR] = perf_event__hdr_attr_swap, 531 [PERF_RECORD_HEADER_EVENT_TYPE] = perf_event__event_type_swap, 532 [PERF_RECORD_HEADER_TRACING_DATA] = perf_event__tracing_data_swap, 533 [PERF_RECORD_HEADER_BUILD_ID] = NULL, 534 [PERF_RECORD_HEADER_MAX] = NULL, 535 }; 536 537 struct sample_queue { 538 u64 timestamp; 539 u64 file_offset; 540 union perf_event *event; 541 struct list_head list; 542 }; 543 544 static void perf_session_free_sample_buffers(struct perf_session *session) 545 { 546 struct ordered_samples *os = &session->ordered_samples; 547 548 while (!list_empty(&os->to_free)) { 549 struct sample_queue *sq; 550 551 sq = list_entry(os->to_free.next, struct sample_queue, list); 552 list_del(&sq->list); 553 free(sq); 554 } 555 } 556 557 static int perf_session_deliver_event(struct perf_session *session, 558 union perf_event *event, 559 struct perf_sample *sample, 560 struct perf_tool *tool, 561 u64 file_offset); 562 563 static void flush_sample_queue(struct perf_session *s, 564 struct perf_tool *tool) 565 { 566 struct ordered_samples *os = &s->ordered_samples; 567 struct list_head *head = &os->samples; 568 struct sample_queue *tmp, *iter; 569 struct perf_sample sample; 570 u64 limit = os->next_flush; 571 u64 last_ts = os->last_sample ? os->last_sample->timestamp : 0ULL; 572 unsigned idx = 0, progress_next = os->nr_samples / 16; 573 int ret; 574 575 if (!tool->ordered_samples || !limit) 576 return; 577 578 list_for_each_entry_safe(iter, tmp, head, list) { 579 if (iter->timestamp > limit) 580 break; 581 582 ret = perf_session__parse_sample(s, iter->event, &sample); 583 if (ret) 584 pr_err("Can't parse sample, err = %d\n", ret); 585 else 586 perf_session_deliver_event(s, iter->event, &sample, tool, 587 iter->file_offset); 588 589 os->last_flush = iter->timestamp; 590 list_del(&iter->list); 591 list_add(&iter->list, &os->sample_cache); 592 if (++idx >= progress_next) { 593 progress_next += os->nr_samples / 16; 594 ui_progress__update(idx, os->nr_samples, 595 "Processing time ordered events..."); 596 } 597 } 598 599 if (list_empty(head)) { 600 os->last_sample = NULL; 601 } else if (last_ts <= limit) { 602 os->last_sample = 603 list_entry(head->prev, struct sample_queue, list); 604 } 605 606 os->nr_samples = 0; 607 } 608 609 /* 610 * When perf record finishes a pass on every buffers, it records this pseudo 611 * event. 612 * We record the max timestamp t found in the pass n. 613 * Assuming these timestamps are monotonic across cpus, we know that if 614 * a buffer still has events with timestamps below t, they will be all 615 * available and then read in the pass n + 1. 616 * Hence when we start to read the pass n + 2, we can safely flush every 617 * events with timestamps below t. 618 * 619 * ============ PASS n ================= 620 * CPU 0 | CPU 1 621 * | 622 * cnt1 timestamps | cnt2 timestamps 623 * 1 | 2 624 * 2 | 3 625 * - | 4 <--- max recorded 626 * 627 * ============ PASS n + 1 ============== 628 * CPU 0 | CPU 1 629 * | 630 * cnt1 timestamps | cnt2 timestamps 631 * 3 | 5 632 * 4 | 6 633 * 5 | 7 <---- max recorded 634 * 635 * Flush every events below timestamp 4 636 * 637 * ============ PASS n + 2 ============== 638 * CPU 0 | CPU 1 639 * | 640 * cnt1 timestamps | cnt2 timestamps 641 * 6 | 8 642 * 7 | 9 643 * - | 10 644 * 645 * Flush every events below timestamp 7 646 * etc... 647 */ 648 static int process_finished_round(struct perf_tool *tool, 649 union perf_event *event __used, 650 struct perf_session *session) 651 { 652 flush_sample_queue(session, tool); 653 session->ordered_samples.next_flush = session->ordered_samples.max_timestamp; 654 655 return 0; 656 } 657 658 /* The queue is ordered by time */ 659 static void __queue_event(struct sample_queue *new, struct perf_session *s) 660 { 661 struct ordered_samples *os = &s->ordered_samples; 662 struct sample_queue *sample = os->last_sample; 663 u64 timestamp = new->timestamp; 664 struct list_head *p; 665 666 ++os->nr_samples; 667 os->last_sample = new; 668 669 if (!sample) { 670 list_add(&new->list, &os->samples); 671 os->max_timestamp = timestamp; 672 return; 673 } 674 675 /* 676 * last_sample might point to some random place in the list as it's 677 * the last queued event. We expect that the new event is close to 678 * this. 679 */ 680 if (sample->timestamp <= timestamp) { 681 while (sample->timestamp <= timestamp) { 682 p = sample->list.next; 683 if (p == &os->samples) { 684 list_add_tail(&new->list, &os->samples); 685 os->max_timestamp = timestamp; 686 return; 687 } 688 sample = list_entry(p, struct sample_queue, list); 689 } 690 list_add_tail(&new->list, &sample->list); 691 } else { 692 while (sample->timestamp > timestamp) { 693 p = sample->list.prev; 694 if (p == &os->samples) { 695 list_add(&new->list, &os->samples); 696 return; 697 } 698 sample = list_entry(p, struct sample_queue, list); 699 } 700 list_add(&new->list, &sample->list); 701 } 702 } 703 704 #define MAX_SAMPLE_BUFFER (64 * 1024 / sizeof(struct sample_queue)) 705 706 static int perf_session_queue_event(struct perf_session *s, union perf_event *event, 707 struct perf_sample *sample, u64 file_offset) 708 { 709 struct ordered_samples *os = &s->ordered_samples; 710 struct list_head *sc = &os->sample_cache; 711 u64 timestamp = sample->time; 712 struct sample_queue *new; 713 714 if (!timestamp || timestamp == ~0ULL) 715 return -ETIME; 716 717 if (timestamp < s->ordered_samples.last_flush) { 718 printf("Warning: Timestamp below last timeslice flush\n"); 719 return -EINVAL; 720 } 721 722 if (!list_empty(sc)) { 723 new = list_entry(sc->next, struct sample_queue, list); 724 list_del(&new->list); 725 } else if (os->sample_buffer) { 726 new = os->sample_buffer + os->sample_buffer_idx; 727 if (++os->sample_buffer_idx == MAX_SAMPLE_BUFFER) 728 os->sample_buffer = NULL; 729 } else { 730 os->sample_buffer = malloc(MAX_SAMPLE_BUFFER * sizeof(*new)); 731 if (!os->sample_buffer) 732 return -ENOMEM; 733 list_add(&os->sample_buffer->list, &os->to_free); 734 os->sample_buffer_idx = 2; 735 new = os->sample_buffer + 1; 736 } 737 738 new->timestamp = timestamp; 739 new->file_offset = file_offset; 740 new->event = event; 741 742 __queue_event(new, s); 743 744 return 0; 745 } 746 747 static void callchain__printf(struct perf_sample *sample) 748 { 749 unsigned int i; 750 751 printf("... chain: nr:%" PRIu64 "\n", sample->callchain->nr); 752 753 for (i = 0; i < sample->callchain->nr; i++) 754 printf("..... %2d: %016" PRIx64 "\n", 755 i, sample->callchain->ips[i]); 756 } 757 758 static void branch_stack__printf(struct perf_sample *sample) 759 { 760 uint64_t i; 761 762 printf("... branch stack: nr:%" PRIu64 "\n", sample->branch_stack->nr); 763 764 for (i = 0; i < sample->branch_stack->nr; i++) 765 printf("..... %2"PRIu64": %016" PRIx64 " -> %016" PRIx64 "\n", 766 i, sample->branch_stack->entries[i].from, 767 sample->branch_stack->entries[i].to); 768 } 769 770 static void perf_session__print_tstamp(struct perf_session *session, 771 union perf_event *event, 772 struct perf_sample *sample) 773 { 774 if (event->header.type != PERF_RECORD_SAMPLE && 775 !session->sample_id_all) { 776 fputs("-1 -1 ", stdout); 777 return; 778 } 779 780 if ((session->sample_type & PERF_SAMPLE_CPU)) 781 printf("%u ", sample->cpu); 782 783 if (session->sample_type & PERF_SAMPLE_TIME) 784 printf("%" PRIu64 " ", sample->time); 785 } 786 787 static void dump_event(struct perf_session *session, union perf_event *event, 788 u64 file_offset, struct perf_sample *sample) 789 { 790 if (!dump_trace) 791 return; 792 793 printf("\n%#" PRIx64 " [%#x]: event: %d\n", 794 file_offset, event->header.size, event->header.type); 795 796 trace_event(event); 797 798 if (sample) 799 perf_session__print_tstamp(session, event, sample); 800 801 printf("%#" PRIx64 " [%#x]: PERF_RECORD_%s", file_offset, 802 event->header.size, perf_event__name(event->header.type)); 803 } 804 805 static void dump_sample(struct perf_session *session, union perf_event *event, 806 struct perf_sample *sample) 807 { 808 if (!dump_trace) 809 return; 810 811 printf("(IP, %d): %d/%d: %#" PRIx64 " period: %" PRIu64 " addr: %#" PRIx64 "\n", 812 event->header.misc, sample->pid, sample->tid, sample->ip, 813 sample->period, sample->addr); 814 815 if (session->sample_type & PERF_SAMPLE_CALLCHAIN) 816 callchain__printf(sample); 817 818 if (session->sample_type & PERF_SAMPLE_BRANCH_STACK) 819 branch_stack__printf(sample); 820 } 821 822 static struct machine * 823 perf_session__find_machine_for_cpumode(struct perf_session *session, 824 union perf_event *event) 825 { 826 const u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK; 827 828 if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) 829 return perf_session__find_machine(session, event->ip.pid); 830 831 return perf_session__find_host_machine(session); 832 } 833 834 static int perf_session_deliver_event(struct perf_session *session, 835 union perf_event *event, 836 struct perf_sample *sample, 837 struct perf_tool *tool, 838 u64 file_offset) 839 { 840 struct perf_evsel *evsel; 841 struct machine *machine; 842 843 dump_event(session, event, file_offset, sample); 844 845 evsel = perf_evlist__id2evsel(session->evlist, sample->id); 846 if (evsel != NULL && event->header.type != PERF_RECORD_SAMPLE) { 847 /* 848 * XXX We're leaving PERF_RECORD_SAMPLE unnacounted here 849 * because the tools right now may apply filters, discarding 850 * some of the samples. For consistency, in the future we 851 * should have something like nr_filtered_samples and remove 852 * the sample->period from total_sample_period, etc, KISS for 853 * now tho. 854 * 855 * Also testing against NULL allows us to handle files without 856 * attr.sample_id_all and/or without PERF_SAMPLE_ID. In the 857 * future probably it'll be a good idea to restrict event 858 * processing via perf_session to files with both set. 859 */ 860 hists__inc_nr_events(&evsel->hists, event->header.type); 861 } 862 863 machine = perf_session__find_machine_for_cpumode(session, event); 864 865 switch (event->header.type) { 866 case PERF_RECORD_SAMPLE: 867 dump_sample(session, event, sample); 868 if (evsel == NULL) { 869 ++session->hists.stats.nr_unknown_id; 870 return -1; 871 } 872 if (machine == NULL) { 873 ++session->hists.stats.nr_unprocessable_samples; 874 return -1; 875 } 876 return tool->sample(tool, event, sample, evsel, machine); 877 case PERF_RECORD_MMAP: 878 return tool->mmap(tool, event, sample, machine); 879 case PERF_RECORD_COMM: 880 return tool->comm(tool, event, sample, machine); 881 case PERF_RECORD_FORK: 882 return tool->fork(tool, event, sample, machine); 883 case PERF_RECORD_EXIT: 884 return tool->exit(tool, event, sample, machine); 885 case PERF_RECORD_LOST: 886 if (tool->lost == perf_event__process_lost) 887 session->hists.stats.total_lost += event->lost.lost; 888 return tool->lost(tool, event, sample, machine); 889 case PERF_RECORD_READ: 890 return tool->read(tool, event, sample, evsel, machine); 891 case PERF_RECORD_THROTTLE: 892 return tool->throttle(tool, event, sample, machine); 893 case PERF_RECORD_UNTHROTTLE: 894 return tool->unthrottle(tool, event, sample, machine); 895 default: 896 ++session->hists.stats.nr_unknown_events; 897 return -1; 898 } 899 } 900 901 static int perf_session__preprocess_sample(struct perf_session *session, 902 union perf_event *event, struct perf_sample *sample) 903 { 904 if (event->header.type != PERF_RECORD_SAMPLE || 905 !(session->sample_type & PERF_SAMPLE_CALLCHAIN)) 906 return 0; 907 908 if (!ip_callchain__valid(sample->callchain, event)) { 909 pr_debug("call-chain problem with event, skipping it.\n"); 910 ++session->hists.stats.nr_invalid_chains; 911 session->hists.stats.total_invalid_chains += sample->period; 912 return -EINVAL; 913 } 914 return 0; 915 } 916 917 static int perf_session__process_user_event(struct perf_session *session, union perf_event *event, 918 struct perf_tool *tool, u64 file_offset) 919 { 920 int err; 921 922 dump_event(session, event, file_offset, NULL); 923 924 /* These events are processed right away */ 925 switch (event->header.type) { 926 case PERF_RECORD_HEADER_ATTR: 927 err = tool->attr(event, &session->evlist); 928 if (err == 0) 929 perf_session__update_sample_type(session); 930 return err; 931 case PERF_RECORD_HEADER_EVENT_TYPE: 932 return tool->event_type(tool, event); 933 case PERF_RECORD_HEADER_TRACING_DATA: 934 /* setup for reading amidst mmap */ 935 lseek(session->fd, file_offset, SEEK_SET); 936 return tool->tracing_data(event, session); 937 case PERF_RECORD_HEADER_BUILD_ID: 938 return tool->build_id(tool, event, session); 939 case PERF_RECORD_FINISHED_ROUND: 940 return tool->finished_round(tool, event, session); 941 default: 942 return -EINVAL; 943 } 944 } 945 946 static int perf_session__process_event(struct perf_session *session, 947 union perf_event *event, 948 struct perf_tool *tool, 949 u64 file_offset) 950 { 951 struct perf_sample sample; 952 int ret; 953 954 if (session->header.needs_swap && 955 perf_event__swap_ops[event->header.type]) 956 perf_event__swap_ops[event->header.type](event); 957 958 if (event->header.type >= PERF_RECORD_HEADER_MAX) 959 return -EINVAL; 960 961 hists__inc_nr_events(&session->hists, event->header.type); 962 963 if (event->header.type >= PERF_RECORD_USER_TYPE_START) 964 return perf_session__process_user_event(session, event, tool, file_offset); 965 966 /* 967 * For all kernel events we get the sample data 968 */ 969 ret = perf_session__parse_sample(session, event, &sample); 970 if (ret) 971 return ret; 972 973 /* Preprocess sample records - precheck callchains */ 974 if (perf_session__preprocess_sample(session, event, &sample)) 975 return 0; 976 977 if (tool->ordered_samples) { 978 ret = perf_session_queue_event(session, event, &sample, 979 file_offset); 980 if (ret != -ETIME) 981 return ret; 982 } 983 984 return perf_session_deliver_event(session, event, &sample, tool, 985 file_offset); 986 } 987 988 void perf_event_header__bswap(struct perf_event_header *self) 989 { 990 self->type = bswap_32(self->type); 991 self->misc = bswap_16(self->misc); 992 self->size = bswap_16(self->size); 993 } 994 995 struct thread *perf_session__findnew(struct perf_session *session, pid_t pid) 996 { 997 return machine__findnew_thread(&session->host_machine, pid); 998 } 999 1000 static struct thread *perf_session__register_idle_thread(struct perf_session *self) 1001 { 1002 struct thread *thread = perf_session__findnew(self, 0); 1003 1004 if (thread == NULL || thread__set_comm(thread, "swapper")) { 1005 pr_err("problem inserting idle task.\n"); 1006 thread = NULL; 1007 } 1008 1009 return thread; 1010 } 1011 1012 static void perf_session__warn_about_errors(const struct perf_session *session, 1013 const struct perf_tool *tool) 1014 { 1015 if (tool->lost == perf_event__process_lost && 1016 session->hists.stats.nr_events[PERF_RECORD_LOST] != 0) { 1017 ui__warning("Processed %d events and lost %d chunks!\n\n" 1018 "Check IO/CPU overload!\n\n", 1019 session->hists.stats.nr_events[0], 1020 session->hists.stats.nr_events[PERF_RECORD_LOST]); 1021 } 1022 1023 if (session->hists.stats.nr_unknown_events != 0) { 1024 ui__warning("Found %u unknown events!\n\n" 1025 "Is this an older tool processing a perf.data " 1026 "file generated by a more recent tool?\n\n" 1027 "If that is not the case, consider " 1028 "reporting to linux-kernel@vger.kernel.org.\n\n", 1029 session->hists.stats.nr_unknown_events); 1030 } 1031 1032 if (session->hists.stats.nr_unknown_id != 0) { 1033 ui__warning("%u samples with id not present in the header\n", 1034 session->hists.stats.nr_unknown_id); 1035 } 1036 1037 if (session->hists.stats.nr_invalid_chains != 0) { 1038 ui__warning("Found invalid callchains!\n\n" 1039 "%u out of %u events were discarded for this reason.\n\n" 1040 "Consider reporting to linux-kernel@vger.kernel.org.\n\n", 1041 session->hists.stats.nr_invalid_chains, 1042 session->hists.stats.nr_events[PERF_RECORD_SAMPLE]); 1043 } 1044 1045 if (session->hists.stats.nr_unprocessable_samples != 0) { 1046 ui__warning("%u unprocessable samples recorded.\n" 1047 "Do you have a KVM guest running and not using 'perf kvm'?\n", 1048 session->hists.stats.nr_unprocessable_samples); 1049 } 1050 } 1051 1052 #define session_done() (*(volatile int *)(&session_done)) 1053 volatile int session_done; 1054 1055 static int __perf_session__process_pipe_events(struct perf_session *self, 1056 struct perf_tool *tool) 1057 { 1058 union perf_event event; 1059 uint32_t size; 1060 int skip = 0; 1061 u64 head; 1062 int err; 1063 void *p; 1064 1065 perf_tool__fill_defaults(tool); 1066 1067 head = 0; 1068 more: 1069 err = readn(self->fd, &event, sizeof(struct perf_event_header)); 1070 if (err <= 0) { 1071 if (err == 0) 1072 goto done; 1073 1074 pr_err("failed to read event header\n"); 1075 goto out_err; 1076 } 1077 1078 if (self->header.needs_swap) 1079 perf_event_header__bswap(&event.header); 1080 1081 size = event.header.size; 1082 if (size == 0) 1083 size = 8; 1084 1085 p = &event; 1086 p += sizeof(struct perf_event_header); 1087 1088 if (size - sizeof(struct perf_event_header)) { 1089 err = readn(self->fd, p, size - sizeof(struct perf_event_header)); 1090 if (err <= 0) { 1091 if (err == 0) { 1092 pr_err("unexpected end of event stream\n"); 1093 goto done; 1094 } 1095 1096 pr_err("failed to read event data\n"); 1097 goto out_err; 1098 } 1099 } 1100 1101 if ((skip = perf_session__process_event(self, &event, tool, head)) < 0) { 1102 dump_printf("%#" PRIx64 " [%#x]: skipping unknown header type: %d\n", 1103 head, event.header.size, event.header.type); 1104 /* 1105 * assume we lost track of the stream, check alignment, and 1106 * increment a single u64 in the hope to catch on again 'soon'. 1107 */ 1108 if (unlikely(head & 7)) 1109 head &= ~7ULL; 1110 1111 size = 8; 1112 } 1113 1114 head += size; 1115 1116 if (skip > 0) 1117 head += skip; 1118 1119 if (!session_done()) 1120 goto more; 1121 done: 1122 err = 0; 1123 out_err: 1124 perf_session__warn_about_errors(self, tool); 1125 perf_session_free_sample_buffers(self); 1126 return err; 1127 } 1128 1129 static union perf_event * 1130 fetch_mmaped_event(struct perf_session *session, 1131 u64 head, size_t mmap_size, char *buf) 1132 { 1133 union perf_event *event; 1134 1135 /* 1136 * Ensure we have enough space remaining to read 1137 * the size of the event in the headers. 1138 */ 1139 if (head + sizeof(event->header) > mmap_size) 1140 return NULL; 1141 1142 event = (union perf_event *)(buf + head); 1143 1144 if (session->header.needs_swap) 1145 perf_event_header__bswap(&event->header); 1146 1147 if (head + event->header.size > mmap_size) 1148 return NULL; 1149 1150 return event; 1151 } 1152 1153 int __perf_session__process_events(struct perf_session *session, 1154 u64 data_offset, u64 data_size, 1155 u64 file_size, struct perf_tool *tool) 1156 { 1157 u64 head, page_offset, file_offset, file_pos, progress_next; 1158 int err, mmap_prot, mmap_flags, map_idx = 0; 1159 size_t page_size, mmap_size; 1160 char *buf, *mmaps[8]; 1161 union perf_event *event; 1162 uint32_t size; 1163 1164 perf_tool__fill_defaults(tool); 1165 1166 page_size = sysconf(_SC_PAGESIZE); 1167 1168 page_offset = page_size * (data_offset / page_size); 1169 file_offset = page_offset; 1170 head = data_offset - page_offset; 1171 1172 if (data_offset + data_size < file_size) 1173 file_size = data_offset + data_size; 1174 1175 progress_next = file_size / 16; 1176 1177 mmap_size = session->mmap_window; 1178 if (mmap_size > file_size) 1179 mmap_size = file_size; 1180 1181 memset(mmaps, 0, sizeof(mmaps)); 1182 1183 mmap_prot = PROT_READ; 1184 mmap_flags = MAP_SHARED; 1185 1186 if (session->header.needs_swap) { 1187 mmap_prot |= PROT_WRITE; 1188 mmap_flags = MAP_PRIVATE; 1189 } 1190 remap: 1191 buf = mmap(NULL, mmap_size, mmap_prot, mmap_flags, session->fd, 1192 file_offset); 1193 if (buf == MAP_FAILED) { 1194 pr_err("failed to mmap file\n"); 1195 err = -errno; 1196 goto out_err; 1197 } 1198 mmaps[map_idx] = buf; 1199 map_idx = (map_idx + 1) & (ARRAY_SIZE(mmaps) - 1); 1200 file_pos = file_offset + head; 1201 1202 more: 1203 event = fetch_mmaped_event(session, head, mmap_size, buf); 1204 if (!event) { 1205 if (mmaps[map_idx]) { 1206 munmap(mmaps[map_idx], mmap_size); 1207 mmaps[map_idx] = NULL; 1208 } 1209 1210 page_offset = page_size * (head / page_size); 1211 file_offset += page_offset; 1212 head -= page_offset; 1213 goto remap; 1214 } 1215 1216 size = event->header.size; 1217 1218 if (size == 0 || 1219 perf_session__process_event(session, event, tool, file_pos) < 0) { 1220 dump_printf("%#" PRIx64 " [%#x]: skipping unknown header type: %d\n", 1221 file_offset + head, event->header.size, 1222 event->header.type); 1223 /* 1224 * assume we lost track of the stream, check alignment, and 1225 * increment a single u64 in the hope to catch on again 'soon'. 1226 */ 1227 if (unlikely(head & 7)) 1228 head &= ~7ULL; 1229 1230 size = 8; 1231 } 1232 1233 head += size; 1234 file_pos += size; 1235 1236 if (file_pos >= progress_next) { 1237 progress_next += file_size / 16; 1238 ui_progress__update(file_pos, file_size, 1239 "Processing events..."); 1240 } 1241 1242 if (file_pos < file_size) 1243 goto more; 1244 1245 err = 0; 1246 /* do the final flush for ordered samples */ 1247 session->ordered_samples.next_flush = ULLONG_MAX; 1248 flush_sample_queue(session, tool); 1249 out_err: 1250 perf_session__warn_about_errors(session, tool); 1251 perf_session_free_sample_buffers(session); 1252 return err; 1253 } 1254 1255 int perf_session__process_events(struct perf_session *self, 1256 struct perf_tool *tool) 1257 { 1258 int err; 1259 1260 if (perf_session__register_idle_thread(self) == NULL) 1261 return -ENOMEM; 1262 1263 if (!self->fd_pipe) 1264 err = __perf_session__process_events(self, 1265 self->header.data_offset, 1266 self->header.data_size, 1267 self->size, tool); 1268 else 1269 err = __perf_session__process_pipe_events(self, tool); 1270 1271 return err; 1272 } 1273 1274 bool perf_session__has_traces(struct perf_session *self, const char *msg) 1275 { 1276 if (!(self->sample_type & PERF_SAMPLE_RAW)) { 1277 pr_err("No trace sample to read. Did you call 'perf %s'?\n", msg); 1278 return false; 1279 } 1280 1281 return true; 1282 } 1283 1284 int maps__set_kallsyms_ref_reloc_sym(struct map **maps, 1285 const char *symbol_name, u64 addr) 1286 { 1287 char *bracket; 1288 enum map_type i; 1289 struct ref_reloc_sym *ref; 1290 1291 ref = zalloc(sizeof(struct ref_reloc_sym)); 1292 if (ref == NULL) 1293 return -ENOMEM; 1294 1295 ref->name = strdup(symbol_name); 1296 if (ref->name == NULL) { 1297 free(ref); 1298 return -ENOMEM; 1299 } 1300 1301 bracket = strchr(ref->name, ']'); 1302 if (bracket) 1303 *bracket = '\0'; 1304 1305 ref->addr = addr; 1306 1307 for (i = 0; i < MAP__NR_TYPES; ++i) { 1308 struct kmap *kmap = map__kmap(maps[i]); 1309 kmap->ref_reloc_sym = ref; 1310 } 1311 1312 return 0; 1313 } 1314 1315 size_t perf_session__fprintf_dsos(struct perf_session *self, FILE *fp) 1316 { 1317 return __dsos__fprintf(&self->host_machine.kernel_dsos, fp) + 1318 __dsos__fprintf(&self->host_machine.user_dsos, fp) + 1319 machines__fprintf_dsos(&self->machines, fp); 1320 } 1321 1322 size_t perf_session__fprintf_dsos_buildid(struct perf_session *self, FILE *fp, 1323 bool with_hits) 1324 { 1325 size_t ret = machine__fprintf_dsos_buildid(&self->host_machine, fp, with_hits); 1326 return ret + machines__fprintf_dsos_buildid(&self->machines, fp, with_hits); 1327 } 1328 1329 size_t perf_session__fprintf_nr_events(struct perf_session *session, FILE *fp) 1330 { 1331 struct perf_evsel *pos; 1332 size_t ret = fprintf(fp, "Aggregated stats:\n"); 1333 1334 ret += hists__fprintf_nr_events(&session->hists, fp); 1335 1336 list_for_each_entry(pos, &session->evlist->entries, node) { 1337 ret += fprintf(fp, "%s stats:\n", event_name(pos)); 1338 ret += hists__fprintf_nr_events(&pos->hists, fp); 1339 } 1340 1341 return ret; 1342 } 1343 1344 size_t perf_session__fprintf(struct perf_session *session, FILE *fp) 1345 { 1346 /* 1347 * FIXME: Here we have to actually print all the machines in this 1348 * session, not just the host... 1349 */ 1350 return machine__fprintf(&session->host_machine, fp); 1351 } 1352 1353 void perf_session__remove_thread(struct perf_session *session, 1354 struct thread *th) 1355 { 1356 /* 1357 * FIXME: This one makes no sense, we need to remove the thread from 1358 * the machine it belongs to, perf_session can have many machines, so 1359 * doing it always on ->host_machine is wrong. Fix when auditing all 1360 * the 'perf kvm' code. 1361 */ 1362 machine__remove_thread(&session->host_machine, th); 1363 } 1364 1365 struct perf_evsel *perf_session__find_first_evtype(struct perf_session *session, 1366 unsigned int type) 1367 { 1368 struct perf_evsel *pos; 1369 1370 list_for_each_entry(pos, &session->evlist->entries, node) { 1371 if (pos->attr.type == type) 1372 return pos; 1373 } 1374 return NULL; 1375 } 1376 1377 void perf_event__print_ip(union perf_event *event, struct perf_sample *sample, 1378 struct machine *machine, struct perf_evsel *evsel, 1379 int print_sym, int print_dso, int print_symoffset) 1380 { 1381 struct addr_location al; 1382 struct callchain_cursor *cursor = &evsel->hists.callchain_cursor; 1383 struct callchain_cursor_node *node; 1384 1385 if (perf_event__preprocess_sample(event, machine, &al, sample, 1386 NULL) < 0) { 1387 error("problem processing %d event, skipping it.\n", 1388 event->header.type); 1389 return; 1390 } 1391 1392 if (symbol_conf.use_callchain && sample->callchain) { 1393 1394 if (machine__resolve_callchain(machine, evsel, al.thread, 1395 sample->callchain, NULL) != 0) { 1396 if (verbose) 1397 error("Failed to resolve callchain. Skipping\n"); 1398 return; 1399 } 1400 callchain_cursor_commit(cursor); 1401 1402 while (1) { 1403 node = callchain_cursor_current(cursor); 1404 if (!node) 1405 break; 1406 1407 printf("\t%16" PRIx64, node->ip); 1408 if (print_sym) { 1409 printf(" "); 1410 symbol__fprintf_symname(node->sym, stdout); 1411 } 1412 if (print_dso) { 1413 printf(" ("); 1414 map__fprintf_dsoname(al.map, stdout); 1415 printf(")"); 1416 } 1417 printf("\n"); 1418 1419 callchain_cursor_advance(cursor); 1420 } 1421 1422 } else { 1423 printf("%16" PRIx64, sample->ip); 1424 if (print_sym) { 1425 printf(" "); 1426 if (print_symoffset) 1427 symbol__fprintf_symname_offs(al.sym, &al, 1428 stdout); 1429 else 1430 symbol__fprintf_symname(al.sym, stdout); 1431 } 1432 1433 if (print_dso) { 1434 printf(" ("); 1435 map__fprintf_dsoname(al.map, stdout); 1436 printf(")"); 1437 } 1438 } 1439 } 1440 1441 int perf_session__cpu_bitmap(struct perf_session *session, 1442 const char *cpu_list, unsigned long *cpu_bitmap) 1443 { 1444 int i; 1445 struct cpu_map *map; 1446 1447 for (i = 0; i < PERF_TYPE_MAX; ++i) { 1448 struct perf_evsel *evsel; 1449 1450 evsel = perf_session__find_first_evtype(session, i); 1451 if (!evsel) 1452 continue; 1453 1454 if (!(evsel->attr.sample_type & PERF_SAMPLE_CPU)) { 1455 pr_err("File does not contain CPU events. " 1456 "Remove -c option to proceed.\n"); 1457 return -1; 1458 } 1459 } 1460 1461 map = cpu_map__new(cpu_list); 1462 if (map == NULL) { 1463 pr_err("Invalid cpu_list\n"); 1464 return -1; 1465 } 1466 1467 for (i = 0; i < map->nr; i++) { 1468 int cpu = map->map[i]; 1469 1470 if (cpu >= MAX_NR_CPUS) { 1471 pr_err("Requested CPU %d too large. " 1472 "Consider raising MAX_NR_CPUS\n", cpu); 1473 return -1; 1474 } 1475 1476 set_bit(cpu, cpu_bitmap); 1477 } 1478 1479 return 0; 1480 } 1481 1482 void perf_session__fprintf_info(struct perf_session *session, FILE *fp, 1483 bool full) 1484 { 1485 struct stat st; 1486 int ret; 1487 1488 if (session == NULL || fp == NULL) 1489 return; 1490 1491 ret = fstat(session->fd, &st); 1492 if (ret == -1) 1493 return; 1494 1495 fprintf(fp, "# ========\n"); 1496 fprintf(fp, "# captured on: %s", ctime(&st.st_ctime)); 1497 perf_header__fprintf_info(session, fp, full); 1498 fprintf(fp, "# ========\n#\n"); 1499 } 1500