1 /* 2 * builtin-top.c 3 * 4 * Builtin top command: Display a continuously updated profile of 5 * any workload, CPU or specific PID. 6 * 7 * Copyright (C) 2008, Red Hat Inc, Ingo Molnar <mingo@redhat.com> 8 * 9 * Improvements and fixes by: 10 * 11 * Arjan van de Ven <arjan@linux.intel.com> 12 * Yanmin Zhang <yanmin.zhang@intel.com> 13 * Wu Fengguang <fengguang.wu@intel.com> 14 * Mike Galbraith <efault@gmx.de> 15 * Paul Mackerras <paulus@samba.org> 16 * 17 * Released under the GPL v2. (and only v2, not any later version) 18 */ 19 #include "builtin.h" 20 21 #include "perf.h" 22 23 #include "util/symbol.h" 24 #include "util/color.h" 25 #include "util/util.h" 26 #include "util/rbtree.h" 27 #include "util/parse-options.h" 28 #include "util/parse-events.h" 29 30 #include <assert.h> 31 #include <fcntl.h> 32 33 #include <stdio.h> 34 35 #include <errno.h> 36 #include <time.h> 37 #include <sched.h> 38 #include <pthread.h> 39 40 #include <sys/syscall.h> 41 #include <sys/ioctl.h> 42 #include <sys/poll.h> 43 #include <sys/prctl.h> 44 #include <sys/wait.h> 45 #include <sys/uio.h> 46 #include <sys/mman.h> 47 48 #include <linux/unistd.h> 49 #include <linux/types.h> 50 51 static int fd[MAX_NR_CPUS][MAX_COUNTERS]; 52 53 static int system_wide = 0; 54 55 static int default_interval = 100000; 56 57 static __u64 count_filter = 5; 58 static int print_entries = 15; 59 60 static int target_pid = -1; 61 static int profile_cpu = -1; 62 static int nr_cpus = 0; 63 static unsigned int realtime_prio = 0; 64 static int group = 0; 65 static unsigned int page_size; 66 static unsigned int mmap_pages = 16; 67 static int freq = 0; 68 static int verbose = 0; 69 70 static char *sym_filter; 71 static unsigned long filter_start; 72 static unsigned long filter_end; 73 74 static int delay_secs = 2; 75 static int zero; 76 static int dump_symtab; 77 78 /* 79 * Symbols 80 */ 81 82 static __u64 min_ip; 83 static __u64 max_ip = -1ll; 84 85 struct sym_entry { 86 struct rb_node rb_node; 87 struct list_head node; 88 unsigned long count[MAX_COUNTERS]; 89 unsigned long snap_count; 90 double weight; 91 int skip; 92 }; 93 94 struct sym_entry *sym_filter_entry; 95 96 struct dso *kernel_dso; 97 98 /* 99 * Symbols will be added here in record_ip and will get out 100 * after decayed. 101 */ 102 static LIST_HEAD(active_symbols); 103 static pthread_mutex_t active_symbols_lock = PTHREAD_MUTEX_INITIALIZER; 104 105 /* 106 * Ordering weight: count-1 * count-2 * ... / count-n 107 */ 108 static double sym_weight(const struct sym_entry *sym) 109 { 110 double weight = sym->snap_count; 111 int counter; 112 113 for (counter = 1; counter < nr_counters-1; counter++) 114 weight *= sym->count[counter]; 115 116 weight /= (sym->count[counter] + 1); 117 118 return weight; 119 } 120 121 static long samples; 122 static long userspace_samples; 123 static const char CONSOLE_CLEAR[] = "[H[2J"; 124 125 static void __list_insert_active_sym(struct sym_entry *syme) 126 { 127 list_add(&syme->node, &active_symbols); 128 } 129 130 static void list_remove_active_sym(struct sym_entry *syme) 131 { 132 pthread_mutex_lock(&active_symbols_lock); 133 list_del_init(&syme->node); 134 pthread_mutex_unlock(&active_symbols_lock); 135 } 136 137 static void rb_insert_active_sym(struct rb_root *tree, struct sym_entry *se) 138 { 139 struct rb_node **p = &tree->rb_node; 140 struct rb_node *parent = NULL; 141 struct sym_entry *iter; 142 143 while (*p != NULL) { 144 parent = *p; 145 iter = rb_entry(parent, struct sym_entry, rb_node); 146 147 if (se->weight > iter->weight) 148 p = &(*p)->rb_left; 149 else 150 p = &(*p)->rb_right; 151 } 152 153 rb_link_node(&se->rb_node, parent, p); 154 rb_insert_color(&se->rb_node, tree); 155 } 156 157 static void print_sym_table(void) 158 { 159 int printed = 0, j; 160 int counter; 161 float samples_per_sec = samples/delay_secs; 162 float ksamples_per_sec = (samples-userspace_samples)/delay_secs; 163 float sum_ksamples = 0.0; 164 struct sym_entry *syme, *n; 165 struct rb_root tmp = RB_ROOT; 166 struct rb_node *nd; 167 168 samples = userspace_samples = 0; 169 170 /* Sort the active symbols */ 171 pthread_mutex_lock(&active_symbols_lock); 172 syme = list_entry(active_symbols.next, struct sym_entry, node); 173 pthread_mutex_unlock(&active_symbols_lock); 174 175 list_for_each_entry_safe_from(syme, n, &active_symbols, node) { 176 syme->snap_count = syme->count[0]; 177 if (syme->snap_count != 0) { 178 syme->weight = sym_weight(syme); 179 rb_insert_active_sym(&tmp, syme); 180 sum_ksamples += syme->snap_count; 181 182 for (j = 0; j < nr_counters; j++) 183 syme->count[j] = zero ? 0 : syme->count[j] * 7 / 8; 184 } else 185 list_remove_active_sym(syme); 186 } 187 188 puts(CONSOLE_CLEAR); 189 190 printf( 191 "------------------------------------------------------------------------------\n"); 192 printf( " PerfTop:%8.0f irqs/sec kernel:%4.1f%% [", 193 samples_per_sec, 194 100.0 - (100.0*((samples_per_sec-ksamples_per_sec)/samples_per_sec))); 195 196 if (nr_counters == 1) { 197 printf("%Ld", attrs[0].sample_period); 198 if (freq) 199 printf("Hz "); 200 else 201 printf(" "); 202 } 203 204 for (counter = 0; counter < nr_counters; counter++) { 205 if (counter) 206 printf("/"); 207 208 printf("%s", event_name(counter)); 209 } 210 211 printf( "], "); 212 213 if (target_pid != -1) 214 printf(" (target_pid: %d", target_pid); 215 else 216 printf(" (all"); 217 218 if (profile_cpu != -1) 219 printf(", cpu: %d)\n", profile_cpu); 220 else { 221 if (target_pid != -1) 222 printf(")\n"); 223 else 224 printf(", %d CPUs)\n", nr_cpus); 225 } 226 227 printf("------------------------------------------------------------------------------\n\n"); 228 229 if (nr_counters == 1) 230 printf(" samples pcnt"); 231 else 232 printf(" weight samples pcnt"); 233 234 printf(" RIP kernel function\n" 235 " ______ _______ _____ ________________ _______________\n\n" 236 ); 237 238 for (nd = rb_first(&tmp); nd; nd = rb_next(nd)) { 239 struct sym_entry *syme = rb_entry(nd, struct sym_entry, rb_node); 240 struct symbol *sym = (struct symbol *)(syme + 1); 241 char *color = PERF_COLOR_NORMAL; 242 double pcnt; 243 244 if (++printed > print_entries || syme->snap_count < count_filter) 245 continue; 246 247 pcnt = 100.0 - (100.0 * ((sum_ksamples - syme->snap_count) / 248 sum_ksamples)); 249 250 /* 251 * We color high-overhead entries in red, mid-overhead 252 * entries in green - and keep the low overhead places 253 * normal: 254 */ 255 if (pcnt >= 5.0) { 256 color = PERF_COLOR_RED; 257 } else { 258 if (pcnt >= 0.5) 259 color = PERF_COLOR_GREEN; 260 } 261 262 if (nr_counters == 1) 263 printf("%20.2f - ", syme->weight); 264 else 265 printf("%9.1f %10ld - ", syme->weight, syme->snap_count); 266 267 color_fprintf(stdout, color, "%4.1f%%", pcnt); 268 printf(" - %016llx : %s\n", sym->start, sym->name); 269 } 270 } 271 272 static void *display_thread(void *arg) 273 { 274 struct pollfd stdin_poll = { .fd = 0, .events = POLLIN }; 275 int delay_msecs = delay_secs * 1000; 276 277 printf("PerfTop refresh period: %d seconds\n", delay_secs); 278 279 do { 280 print_sym_table(); 281 } while (!poll(&stdin_poll, 1, delay_msecs) == 1); 282 283 printf("key pressed - exiting.\n"); 284 exit(0); 285 286 return NULL; 287 } 288 289 static int symbol_filter(struct dso *self, struct symbol *sym) 290 { 291 static int filter_match; 292 struct sym_entry *syme; 293 const char *name = sym->name; 294 295 if (!strcmp(name, "_text") || 296 !strcmp(name, "_etext") || 297 !strcmp(name, "_sinittext") || 298 !strncmp("init_module", name, 11) || 299 !strncmp("cleanup_module", name, 14) || 300 strstr(name, "_text_start") || 301 strstr(name, "_text_end")) 302 return 1; 303 304 syme = dso__sym_priv(self, sym); 305 /* Tag samples to be skipped. */ 306 if (!strcmp("default_idle", name) || 307 !strcmp("cpu_idle", name) || 308 !strcmp("enter_idle", name) || 309 !strcmp("exit_idle", name) || 310 !strcmp("mwait_idle", name)) 311 syme->skip = 1; 312 313 if (filter_match == 1) { 314 filter_end = sym->start; 315 filter_match = -1; 316 if (filter_end - filter_start > 10000) { 317 fprintf(stderr, 318 "hm, too large filter symbol <%s> - skipping.\n", 319 sym_filter); 320 fprintf(stderr, "symbol filter start: %016lx\n", 321 filter_start); 322 fprintf(stderr, " end: %016lx\n", 323 filter_end); 324 filter_end = filter_start = 0; 325 sym_filter = NULL; 326 sleep(1); 327 } 328 } 329 330 if (filter_match == 0 && sym_filter && !strcmp(name, sym_filter)) { 331 filter_match = 1; 332 filter_start = sym->start; 333 } 334 335 336 return 0; 337 } 338 339 static int parse_symbols(void) 340 { 341 struct rb_node *node; 342 struct symbol *sym; 343 344 kernel_dso = dso__new("[kernel]", sizeof(struct sym_entry)); 345 if (kernel_dso == NULL) 346 return -1; 347 348 if (dso__load_kernel(kernel_dso, NULL, symbol_filter, 1) != 0) 349 goto out_delete_dso; 350 351 node = rb_first(&kernel_dso->syms); 352 sym = rb_entry(node, struct symbol, rb_node); 353 min_ip = sym->start; 354 355 node = rb_last(&kernel_dso->syms); 356 sym = rb_entry(node, struct symbol, rb_node); 357 max_ip = sym->end; 358 359 if (dump_symtab) 360 dso__fprintf(kernel_dso, stderr); 361 362 return 0; 363 364 out_delete_dso: 365 dso__delete(kernel_dso); 366 kernel_dso = NULL; 367 return -1; 368 } 369 370 #define TRACE_COUNT 3 371 372 /* 373 * Binary search in the histogram table and record the hit: 374 */ 375 static void record_ip(__u64 ip, int counter) 376 { 377 struct symbol *sym = dso__find_symbol(kernel_dso, ip); 378 379 if (sym != NULL) { 380 struct sym_entry *syme = dso__sym_priv(kernel_dso, sym); 381 382 if (!syme->skip) { 383 syme->count[counter]++; 384 pthread_mutex_lock(&active_symbols_lock); 385 if (list_empty(&syme->node) || !syme->node.next) 386 __list_insert_active_sym(syme); 387 pthread_mutex_unlock(&active_symbols_lock); 388 return; 389 } 390 } 391 392 samples--; 393 } 394 395 static void process_event(__u64 ip, int counter) 396 { 397 samples++; 398 399 if (ip < min_ip || ip > max_ip) { 400 userspace_samples++; 401 return; 402 } 403 404 record_ip(ip, counter); 405 } 406 407 struct mmap_data { 408 int counter; 409 void *base; 410 unsigned int mask; 411 unsigned int prev; 412 }; 413 414 static unsigned int mmap_read_head(struct mmap_data *md) 415 { 416 struct perf_counter_mmap_page *pc = md->base; 417 int head; 418 419 head = pc->data_head; 420 rmb(); 421 422 return head; 423 } 424 425 struct timeval last_read, this_read; 426 427 static void mmap_read_counter(struct mmap_data *md) 428 { 429 unsigned int head = mmap_read_head(md); 430 unsigned int old = md->prev; 431 unsigned char *data = md->base + page_size; 432 int diff; 433 434 gettimeofday(&this_read, NULL); 435 436 /* 437 * If we're further behind than half the buffer, there's a chance 438 * the writer will bite our tail and mess up the samples under us. 439 * 440 * If we somehow ended up ahead of the head, we got messed up. 441 * 442 * In either case, truncate and restart at head. 443 */ 444 diff = head - old; 445 if (diff > md->mask / 2 || diff < 0) { 446 struct timeval iv; 447 unsigned long msecs; 448 449 timersub(&this_read, &last_read, &iv); 450 msecs = iv.tv_sec*1000 + iv.tv_usec/1000; 451 452 fprintf(stderr, "WARNING: failed to keep up with mmap data." 453 " Last read %lu msecs ago.\n", msecs); 454 455 /* 456 * head points to a known good entry, start there. 457 */ 458 old = head; 459 } 460 461 last_read = this_read; 462 463 for (; old != head;) { 464 struct ip_event { 465 struct perf_event_header header; 466 __u64 ip; 467 __u32 pid, target_pid; 468 }; 469 struct mmap_event { 470 struct perf_event_header header; 471 __u32 pid, target_pid; 472 __u64 start; 473 __u64 len; 474 __u64 pgoff; 475 char filename[PATH_MAX]; 476 }; 477 478 typedef union event_union { 479 struct perf_event_header header; 480 struct ip_event ip; 481 struct mmap_event mmap; 482 } event_t; 483 484 event_t *event = (event_t *)&data[old & md->mask]; 485 486 event_t event_copy; 487 488 size_t size = event->header.size; 489 490 /* 491 * Event straddles the mmap boundary -- header should always 492 * be inside due to u64 alignment of output. 493 */ 494 if ((old & md->mask) + size != ((old + size) & md->mask)) { 495 unsigned int offset = old; 496 unsigned int len = min(sizeof(*event), size), cpy; 497 void *dst = &event_copy; 498 499 do { 500 cpy = min(md->mask + 1 - (offset & md->mask), len); 501 memcpy(dst, &data[offset & md->mask], cpy); 502 offset += cpy; 503 dst += cpy; 504 len -= cpy; 505 } while (len); 506 507 event = &event_copy; 508 } 509 510 old += size; 511 512 if (event->header.misc & PERF_EVENT_MISC_OVERFLOW) { 513 if (event->header.type & PERF_SAMPLE_IP) 514 process_event(event->ip.ip, md->counter); 515 } 516 } 517 518 md->prev = old; 519 } 520 521 static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS]; 522 static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS]; 523 524 static void mmap_read(void) 525 { 526 int i, counter; 527 528 for (i = 0; i < nr_cpus; i++) { 529 for (counter = 0; counter < nr_counters; counter++) 530 mmap_read_counter(&mmap_array[i][counter]); 531 } 532 } 533 534 int nr_poll; 535 int group_fd; 536 537 static void start_counter(int i, int counter) 538 { 539 struct perf_counter_attr *attr; 540 unsigned int cpu; 541 542 cpu = profile_cpu; 543 if (target_pid == -1 && profile_cpu == -1) 544 cpu = i; 545 546 attr = attrs + counter; 547 548 attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID; 549 attr->freq = freq; 550 551 try_again: 552 fd[i][counter] = sys_perf_counter_open(attr, target_pid, cpu, group_fd, 0); 553 554 if (fd[i][counter] < 0) { 555 int err = errno; 556 557 if (err == EPERM) 558 die("No permission - are you root?\n"); 559 /* 560 * If it's cycles then fall back to hrtimer 561 * based cpu-clock-tick sw counter, which 562 * is always available even if no PMU support: 563 */ 564 if (attr->type == PERF_TYPE_HARDWARE 565 && attr->config == PERF_COUNT_HW_CPU_CYCLES) { 566 567 if (verbose) 568 warning(" ... trying to fall back to cpu-clock-ticks\n"); 569 570 attr->type = PERF_TYPE_SOFTWARE; 571 attr->config = PERF_COUNT_SW_CPU_CLOCK; 572 goto try_again; 573 } 574 printf("\n"); 575 error("perfcounter syscall returned with %d (%s)\n", 576 fd[i][counter], strerror(err)); 577 die("No CONFIG_PERF_COUNTERS=y kernel support configured?\n"); 578 exit(-1); 579 } 580 assert(fd[i][counter] >= 0); 581 fcntl(fd[i][counter], F_SETFL, O_NONBLOCK); 582 583 /* 584 * First counter acts as the group leader: 585 */ 586 if (group && group_fd == -1) 587 group_fd = fd[i][counter]; 588 589 event_array[nr_poll].fd = fd[i][counter]; 590 event_array[nr_poll].events = POLLIN; 591 nr_poll++; 592 593 mmap_array[i][counter].counter = counter; 594 mmap_array[i][counter].prev = 0; 595 mmap_array[i][counter].mask = mmap_pages*page_size - 1; 596 mmap_array[i][counter].base = mmap(NULL, (mmap_pages+1)*page_size, 597 PROT_READ, MAP_SHARED, fd[i][counter], 0); 598 if (mmap_array[i][counter].base == MAP_FAILED) 599 die("failed to mmap with %d (%s)\n", errno, strerror(errno)); 600 } 601 602 static int __cmd_top(void) 603 { 604 pthread_t thread; 605 int i, counter; 606 int ret; 607 608 for (i = 0; i < nr_cpus; i++) { 609 group_fd = -1; 610 for (counter = 0; counter < nr_counters; counter++) 611 start_counter(i, counter); 612 } 613 614 /* Wait for a minimal set of events before starting the snapshot */ 615 poll(event_array, nr_poll, 100); 616 617 mmap_read(); 618 619 if (pthread_create(&thread, NULL, display_thread, NULL)) { 620 printf("Could not create display thread.\n"); 621 exit(-1); 622 } 623 624 if (realtime_prio) { 625 struct sched_param param; 626 627 param.sched_priority = realtime_prio; 628 if (sched_setscheduler(0, SCHED_FIFO, ¶m)) { 629 printf("Could not set realtime priority.\n"); 630 exit(-1); 631 } 632 } 633 634 while (1) { 635 int hits = samples; 636 637 mmap_read(); 638 639 if (hits == samples) 640 ret = poll(event_array, nr_poll, 100); 641 } 642 643 return 0; 644 } 645 646 static const char * const top_usage[] = { 647 "perf top [<options>]", 648 NULL 649 }; 650 651 static const struct option options[] = { 652 OPT_CALLBACK('e', "event", NULL, "event", 653 "event selector. use 'perf list' to list available events", 654 parse_events), 655 OPT_INTEGER('c', "count", &default_interval, 656 "event period to sample"), 657 OPT_INTEGER('p', "pid", &target_pid, 658 "profile events on existing pid"), 659 OPT_BOOLEAN('a', "all-cpus", &system_wide, 660 "system-wide collection from all CPUs"), 661 OPT_INTEGER('C', "CPU", &profile_cpu, 662 "CPU to profile on"), 663 OPT_INTEGER('m', "mmap-pages", &mmap_pages, 664 "number of mmap data pages"), 665 OPT_INTEGER('r', "realtime", &realtime_prio, 666 "collect data with this RT SCHED_FIFO priority"), 667 OPT_INTEGER('d', "delay", &delay_secs, 668 "number of seconds to delay between refreshes"), 669 OPT_BOOLEAN('D', "dump-symtab", &dump_symtab, 670 "dump the symbol table used for profiling"), 671 OPT_INTEGER('f', "count-filter", &count_filter, 672 "only display functions with more events than this"), 673 OPT_BOOLEAN('g', "group", &group, 674 "put the counters into a counter group"), 675 OPT_STRING('s', "sym-filter", &sym_filter, "pattern", 676 "only display symbols matchig this pattern"), 677 OPT_BOOLEAN('z', "zero", &group, 678 "zero history across updates"), 679 OPT_INTEGER('F', "freq", &freq, 680 "profile at this frequency"), 681 OPT_INTEGER('E', "entries", &print_entries, 682 "display this many functions"), 683 OPT_BOOLEAN('v', "verbose", &verbose, 684 "be more verbose (show counter open errors, etc)"), 685 OPT_END() 686 }; 687 688 int cmd_top(int argc, const char **argv, const char *prefix) 689 { 690 int counter; 691 692 page_size = sysconf(_SC_PAGE_SIZE); 693 694 argc = parse_options(argc, argv, options, top_usage, 0); 695 if (argc) 696 usage_with_options(top_usage, options); 697 698 if (freq) { 699 default_interval = freq; 700 freq = 1; 701 } 702 703 /* CPU and PID are mutually exclusive */ 704 if (target_pid != -1 && profile_cpu != -1) { 705 printf("WARNING: PID switch overriding CPU\n"); 706 sleep(1); 707 profile_cpu = -1; 708 } 709 710 if (!nr_counters) 711 nr_counters = 1; 712 713 if (delay_secs < 1) 714 delay_secs = 1; 715 716 parse_symbols(); 717 718 /* 719 * Fill in the ones not specifically initialized via -c: 720 */ 721 for (counter = 0; counter < nr_counters; counter++) { 722 if (attrs[counter].sample_period) 723 continue; 724 725 attrs[counter].sample_period = default_interval; 726 } 727 728 nr_cpus = sysconf(_SC_NPROCESSORS_ONLN); 729 assert(nr_cpus <= MAX_NR_CPUS); 730 assert(nr_cpus >= 0); 731 732 if (target_pid != -1 || profile_cpu != -1) 733 nr_cpus = 1; 734 735 return __cmd_top(); 736 } 737