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 <linux/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 static char *vmlinux = NULL; 70 71 static char *sym_filter; 72 static unsigned long filter_start; 73 static unsigned long filter_end; 74 75 static int delay_secs = 2; 76 static int zero; 77 static int dump_symtab; 78 79 /* 80 * Symbols 81 */ 82 83 static u64 min_ip; 84 static u64 max_ip = -1ll; 85 86 struct sym_entry { 87 struct rb_node rb_node; 88 struct list_head node; 89 unsigned long count[MAX_COUNTERS]; 90 unsigned long snap_count; 91 double weight; 92 int skip; 93 }; 94 95 struct sym_entry *sym_filter_entry; 96 97 struct dso *kernel_dso; 98 99 /* 100 * Symbols will be added here in record_ip and will get out 101 * after decayed. 102 */ 103 static LIST_HEAD(active_symbols); 104 static pthread_mutex_t active_symbols_lock = PTHREAD_MUTEX_INITIALIZER; 105 106 /* 107 * Ordering weight: count-1 * count-2 * ... / count-n 108 */ 109 static double sym_weight(const struct sym_entry *sym) 110 { 111 double weight = sym->snap_count; 112 int counter; 113 114 for (counter = 1; counter < nr_counters-1; counter++) 115 weight *= sym->count[counter]; 116 117 weight /= (sym->count[counter] + 1); 118 119 return weight; 120 } 121 122 static long samples; 123 static long userspace_samples; 124 static const char CONSOLE_CLEAR[] = "[H[2J"; 125 126 static void __list_insert_active_sym(struct sym_entry *syme) 127 { 128 list_add(&syme->node, &active_symbols); 129 } 130 131 static void list_remove_active_sym(struct sym_entry *syme) 132 { 133 pthread_mutex_lock(&active_symbols_lock); 134 list_del_init(&syme->node); 135 pthread_mutex_unlock(&active_symbols_lock); 136 } 137 138 static void rb_insert_active_sym(struct rb_root *tree, struct sym_entry *se) 139 { 140 struct rb_node **p = &tree->rb_node; 141 struct rb_node *parent = NULL; 142 struct sym_entry *iter; 143 144 while (*p != NULL) { 145 parent = *p; 146 iter = rb_entry(parent, struct sym_entry, rb_node); 147 148 if (se->weight > iter->weight) 149 p = &(*p)->rb_left; 150 else 151 p = &(*p)->rb_right; 152 } 153 154 rb_link_node(&se->rb_node, parent, p); 155 rb_insert_color(&se->rb_node, tree); 156 } 157 158 static void print_sym_table(void) 159 { 160 int printed = 0, j; 161 int counter; 162 float samples_per_sec = samples/delay_secs; 163 float ksamples_per_sec = (samples-userspace_samples)/delay_secs; 164 float sum_ksamples = 0.0; 165 struct sym_entry *syme, *n; 166 struct rb_root tmp = RB_ROOT; 167 struct rb_node *nd; 168 169 samples = userspace_samples = 0; 170 171 /* Sort the active symbols */ 172 pthread_mutex_lock(&active_symbols_lock); 173 syme = list_entry(active_symbols.next, struct sym_entry, node); 174 pthread_mutex_unlock(&active_symbols_lock); 175 176 list_for_each_entry_safe_from(syme, n, &active_symbols, node) { 177 syme->snap_count = syme->count[0]; 178 if (syme->snap_count != 0) { 179 syme->weight = sym_weight(syme); 180 rb_insert_active_sym(&tmp, syme); 181 sum_ksamples += syme->snap_count; 182 183 for (j = 0; j < nr_counters; j++) 184 syme->count[j] = zero ? 0 : syme->count[j] * 7 / 8; 185 } else 186 list_remove_active_sym(syme); 187 } 188 189 puts(CONSOLE_CLEAR); 190 191 printf( 192 "------------------------------------------------------------------------------\n"); 193 printf( " PerfTop:%8.0f irqs/sec kernel:%4.1f%% [", 194 samples_per_sec, 195 100.0 - (100.0*((samples_per_sec-ksamples_per_sec)/samples_per_sec))); 196 197 if (nr_counters == 1) { 198 printf("%Ld", (u64)attrs[0].sample_period); 199 if (freq) 200 printf("Hz "); 201 else 202 printf(" "); 203 } 204 205 for (counter = 0; counter < nr_counters; counter++) { 206 if (counter) 207 printf("/"); 208 209 printf("%s", event_name(counter)); 210 } 211 212 printf( "], "); 213 214 if (target_pid != -1) 215 printf(" (target_pid: %d", target_pid); 216 else 217 printf(" (all"); 218 219 if (profile_cpu != -1) 220 printf(", cpu: %d)\n", profile_cpu); 221 else { 222 if (target_pid != -1) 223 printf(")\n"); 224 else 225 printf(", %d CPUs)\n", nr_cpus); 226 } 227 228 printf("------------------------------------------------------------------------------\n\n"); 229 230 if (nr_counters == 1) 231 printf(" samples pcnt"); 232 else 233 printf(" weight samples pcnt"); 234 235 printf(" RIP kernel function\n" 236 " ______ _______ _____ ________________ _______________\n\n" 237 ); 238 239 for (nd = rb_first(&tmp); nd; nd = rb_next(nd)) { 240 struct sym_entry *syme = rb_entry(nd, struct sym_entry, rb_node); 241 struct symbol *sym = (struct symbol *)(syme + 1); 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 if (nr_counters == 1) 251 printf("%20.2f - ", syme->weight); 252 else 253 printf("%9.1f %10ld - ", syme->weight, syme->snap_count); 254 255 percent_color_fprintf(stdout, "%4.1f%%", pcnt); 256 printf(" - %016llx : %s", sym->start, sym->name); 257 if (sym->module) 258 printf("\t[%s]", sym->module->name); 259 printf("\n"); 260 } 261 } 262 263 static void *display_thread(void *arg __used) 264 { 265 struct pollfd stdin_poll = { .fd = 0, .events = POLLIN }; 266 int delay_msecs = delay_secs * 1000; 267 268 printf("PerfTop refresh period: %d seconds\n", delay_secs); 269 270 do { 271 print_sym_table(); 272 } while (!poll(&stdin_poll, 1, delay_msecs) == 1); 273 274 printf("key pressed - exiting.\n"); 275 exit(0); 276 277 return NULL; 278 } 279 280 /* Tag samples to be skipped. */ 281 static const char *skip_symbols[] = { 282 "default_idle", 283 "cpu_idle", 284 "enter_idle", 285 "exit_idle", 286 "mwait_idle", 287 "ppc64_runlatch_off", 288 "pseries_dedicated_idle_sleep", 289 NULL 290 }; 291 292 static int symbol_filter(struct dso *self, struct symbol *sym) 293 { 294 static int filter_match; 295 struct sym_entry *syme; 296 const char *name = sym->name; 297 int i; 298 299 /* 300 * ppc64 uses function descriptors and appends a '.' to the 301 * start of every instruction address. Remove it. 302 */ 303 if (name[0] == '.') 304 name++; 305 306 if (!strcmp(name, "_text") || 307 !strcmp(name, "_etext") || 308 !strcmp(name, "_sinittext") || 309 !strncmp("init_module", name, 11) || 310 !strncmp("cleanup_module", name, 14) || 311 strstr(name, "_text_start") || 312 strstr(name, "_text_end")) 313 return 1; 314 315 syme = dso__sym_priv(self, sym); 316 for (i = 0; skip_symbols[i]; i++) { 317 if (!strcmp(skip_symbols[i], name)) { 318 syme->skip = 1; 319 break; 320 } 321 } 322 323 if (filter_match == 1) { 324 filter_end = sym->start; 325 filter_match = -1; 326 if (filter_end - filter_start > 10000) { 327 fprintf(stderr, 328 "hm, too large filter symbol <%s> - skipping.\n", 329 sym_filter); 330 fprintf(stderr, "symbol filter start: %016lx\n", 331 filter_start); 332 fprintf(stderr, " end: %016lx\n", 333 filter_end); 334 filter_end = filter_start = 0; 335 sym_filter = NULL; 336 sleep(1); 337 } 338 } 339 340 if (filter_match == 0 && sym_filter && !strcmp(name, sym_filter)) { 341 filter_match = 1; 342 filter_start = sym->start; 343 } 344 345 346 return 0; 347 } 348 349 static int parse_symbols(void) 350 { 351 struct rb_node *node; 352 struct symbol *sym; 353 int modules = vmlinux ? 1 : 0; 354 355 kernel_dso = dso__new("[kernel]", sizeof(struct sym_entry)); 356 if (kernel_dso == NULL) 357 return -1; 358 359 if (dso__load_kernel(kernel_dso, vmlinux, symbol_filter, verbose, modules) <= 0) 360 goto out_delete_dso; 361 362 node = rb_first(&kernel_dso->syms); 363 sym = rb_entry(node, struct symbol, rb_node); 364 min_ip = sym->start; 365 366 node = rb_last(&kernel_dso->syms); 367 sym = rb_entry(node, struct symbol, rb_node); 368 max_ip = sym->end; 369 370 if (dump_symtab) 371 dso__fprintf(kernel_dso, stderr); 372 373 return 0; 374 375 out_delete_dso: 376 dso__delete(kernel_dso); 377 kernel_dso = NULL; 378 return -1; 379 } 380 381 #define TRACE_COUNT 3 382 383 /* 384 * Binary search in the histogram table and record the hit: 385 */ 386 static void record_ip(u64 ip, int counter) 387 { 388 struct symbol *sym = dso__find_symbol(kernel_dso, ip); 389 390 if (sym != NULL) { 391 struct sym_entry *syme = dso__sym_priv(kernel_dso, sym); 392 393 if (!syme->skip) { 394 syme->count[counter]++; 395 pthread_mutex_lock(&active_symbols_lock); 396 if (list_empty(&syme->node) || !syme->node.next) 397 __list_insert_active_sym(syme); 398 pthread_mutex_unlock(&active_symbols_lock); 399 return; 400 } 401 } 402 403 samples--; 404 } 405 406 static void process_event(u64 ip, int counter, int user) 407 { 408 samples++; 409 410 if (user) { 411 userspace_samples++; 412 return; 413 } 414 415 record_ip(ip, counter); 416 } 417 418 struct mmap_data { 419 int counter; 420 void *base; 421 int mask; 422 unsigned int prev; 423 }; 424 425 static unsigned int mmap_read_head(struct mmap_data *md) 426 { 427 struct perf_counter_mmap_page *pc = md->base; 428 int head; 429 430 head = pc->data_head; 431 rmb(); 432 433 return head; 434 } 435 436 struct timeval last_read, this_read; 437 438 static void mmap_read_counter(struct mmap_data *md) 439 { 440 unsigned int head = mmap_read_head(md); 441 unsigned int old = md->prev; 442 unsigned char *data = md->base + page_size; 443 int diff; 444 445 gettimeofday(&this_read, NULL); 446 447 /* 448 * If we're further behind than half the buffer, there's a chance 449 * the writer will bite our tail and mess up the samples under us. 450 * 451 * If we somehow ended up ahead of the head, we got messed up. 452 * 453 * In either case, truncate and restart at head. 454 */ 455 diff = head - old; 456 if (diff > md->mask / 2 || diff < 0) { 457 struct timeval iv; 458 unsigned long msecs; 459 460 timersub(&this_read, &last_read, &iv); 461 msecs = iv.tv_sec*1000 + iv.tv_usec/1000; 462 463 fprintf(stderr, "WARNING: failed to keep up with mmap data." 464 " Last read %lu msecs ago.\n", msecs); 465 466 /* 467 * head points to a known good entry, start there. 468 */ 469 old = head; 470 } 471 472 last_read = this_read; 473 474 for (; old != head;) { 475 struct ip_event { 476 struct perf_event_header header; 477 u64 ip; 478 u32 pid, target_pid; 479 }; 480 struct mmap_event { 481 struct perf_event_header header; 482 u32 pid, target_pid; 483 u64 start; 484 u64 len; 485 u64 pgoff; 486 char filename[PATH_MAX]; 487 }; 488 489 typedef union event_union { 490 struct perf_event_header header; 491 struct ip_event ip; 492 struct mmap_event mmap; 493 } event_t; 494 495 event_t *event = (event_t *)&data[old & md->mask]; 496 497 event_t event_copy; 498 499 size_t size = event->header.size; 500 501 /* 502 * Event straddles the mmap boundary -- header should always 503 * be inside due to u64 alignment of output. 504 */ 505 if ((old & md->mask) + size != ((old + size) & md->mask)) { 506 unsigned int offset = old; 507 unsigned int len = min(sizeof(*event), size), cpy; 508 void *dst = &event_copy; 509 510 do { 511 cpy = min(md->mask + 1 - (offset & md->mask), len); 512 memcpy(dst, &data[offset & md->mask], cpy); 513 offset += cpy; 514 dst += cpy; 515 len -= cpy; 516 } while (len); 517 518 event = &event_copy; 519 } 520 521 old += size; 522 523 if (event->header.type == PERF_EVENT_SAMPLE) { 524 int user = 525 (event->header.misc & PERF_EVENT_MISC_CPUMODE_MASK) == PERF_EVENT_MISC_USER; 526 process_event(event->ip.ip, md->counter, user); 527 } 528 } 529 530 md->prev = old; 531 } 532 533 static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS]; 534 static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS]; 535 536 static void mmap_read(void) 537 { 538 int i, counter; 539 540 for (i = 0; i < nr_cpus; i++) { 541 for (counter = 0; counter < nr_counters; counter++) 542 mmap_read_counter(&mmap_array[i][counter]); 543 } 544 } 545 546 int nr_poll; 547 int group_fd; 548 549 static void start_counter(int i, int counter) 550 { 551 struct perf_counter_attr *attr; 552 unsigned int cpu; 553 554 cpu = profile_cpu; 555 if (target_pid == -1 && profile_cpu == -1) 556 cpu = i; 557 558 attr = attrs + counter; 559 560 attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID; 561 attr->freq = freq; 562 563 try_again: 564 fd[i][counter] = sys_perf_counter_open(attr, target_pid, cpu, group_fd, 0); 565 566 if (fd[i][counter] < 0) { 567 int err = errno; 568 569 if (err == EPERM) 570 die("No permission - are you root?\n"); 571 /* 572 * If it's cycles then fall back to hrtimer 573 * based cpu-clock-tick sw counter, which 574 * is always available even if no PMU support: 575 */ 576 if (attr->type == PERF_TYPE_HARDWARE 577 && attr->config == PERF_COUNT_HW_CPU_CYCLES) { 578 579 if (verbose) 580 warning(" ... trying to fall back to cpu-clock-ticks\n"); 581 582 attr->type = PERF_TYPE_SOFTWARE; 583 attr->config = PERF_COUNT_SW_CPU_CLOCK; 584 goto try_again; 585 } 586 printf("\n"); 587 error("perfcounter syscall returned with %d (%s)\n", 588 fd[i][counter], strerror(err)); 589 die("No CONFIG_PERF_COUNTERS=y kernel support configured?\n"); 590 exit(-1); 591 } 592 assert(fd[i][counter] >= 0); 593 fcntl(fd[i][counter], F_SETFL, O_NONBLOCK); 594 595 /* 596 * First counter acts as the group leader: 597 */ 598 if (group && group_fd == -1) 599 group_fd = fd[i][counter]; 600 601 event_array[nr_poll].fd = fd[i][counter]; 602 event_array[nr_poll].events = POLLIN; 603 nr_poll++; 604 605 mmap_array[i][counter].counter = counter; 606 mmap_array[i][counter].prev = 0; 607 mmap_array[i][counter].mask = mmap_pages*page_size - 1; 608 mmap_array[i][counter].base = mmap(NULL, (mmap_pages+1)*page_size, 609 PROT_READ, MAP_SHARED, fd[i][counter], 0); 610 if (mmap_array[i][counter].base == MAP_FAILED) 611 die("failed to mmap with %d (%s)\n", errno, strerror(errno)); 612 } 613 614 static int __cmd_top(void) 615 { 616 pthread_t thread; 617 int i, counter; 618 int ret; 619 620 for (i = 0; i < nr_cpus; i++) { 621 group_fd = -1; 622 for (counter = 0; counter < nr_counters; counter++) 623 start_counter(i, counter); 624 } 625 626 /* Wait for a minimal set of events before starting the snapshot */ 627 poll(event_array, nr_poll, 100); 628 629 mmap_read(); 630 631 if (pthread_create(&thread, NULL, display_thread, NULL)) { 632 printf("Could not create display thread.\n"); 633 exit(-1); 634 } 635 636 if (realtime_prio) { 637 struct sched_param param; 638 639 param.sched_priority = realtime_prio; 640 if (sched_setscheduler(0, SCHED_FIFO, ¶m)) { 641 printf("Could not set realtime priority.\n"); 642 exit(-1); 643 } 644 } 645 646 while (1) { 647 int hits = samples; 648 649 mmap_read(); 650 651 if (hits == samples) 652 ret = poll(event_array, nr_poll, 100); 653 } 654 655 return 0; 656 } 657 658 static const char * const top_usage[] = { 659 "perf top [<options>]", 660 NULL 661 }; 662 663 static const struct option options[] = { 664 OPT_CALLBACK('e', "event", NULL, "event", 665 "event selector. use 'perf list' to list available events", 666 parse_events), 667 OPT_INTEGER('c', "count", &default_interval, 668 "event period to sample"), 669 OPT_INTEGER('p', "pid", &target_pid, 670 "profile events on existing pid"), 671 OPT_BOOLEAN('a', "all-cpus", &system_wide, 672 "system-wide collection from all CPUs"), 673 OPT_INTEGER('C', "CPU", &profile_cpu, 674 "CPU to profile on"), 675 OPT_STRING('k', "vmlinux", &vmlinux, "file", "vmlinux pathname"), 676 OPT_INTEGER('m', "mmap-pages", &mmap_pages, 677 "number of mmap data pages"), 678 OPT_INTEGER('r', "realtime", &realtime_prio, 679 "collect data with this RT SCHED_FIFO priority"), 680 OPT_INTEGER('d', "delay", &delay_secs, 681 "number of seconds to delay between refreshes"), 682 OPT_BOOLEAN('D', "dump-symtab", &dump_symtab, 683 "dump the symbol table used for profiling"), 684 OPT_INTEGER('f', "count-filter", &count_filter, 685 "only display functions with more events than this"), 686 OPT_BOOLEAN('g', "group", &group, 687 "put the counters into a counter group"), 688 OPT_STRING('s', "sym-filter", &sym_filter, "pattern", 689 "only display symbols matchig this pattern"), 690 OPT_BOOLEAN('z', "zero", &zero, 691 "zero history across updates"), 692 OPT_INTEGER('F', "freq", &freq, 693 "profile at this frequency"), 694 OPT_INTEGER('E', "entries", &print_entries, 695 "display this many functions"), 696 OPT_BOOLEAN('v', "verbose", &verbose, 697 "be more verbose (show counter open errors, etc)"), 698 OPT_END() 699 }; 700 701 int cmd_top(int argc, const char **argv, const char *prefix __used) 702 { 703 int counter; 704 705 symbol__init(); 706 707 page_size = sysconf(_SC_PAGE_SIZE); 708 709 argc = parse_options(argc, argv, options, top_usage, 0); 710 if (argc) 711 usage_with_options(top_usage, options); 712 713 if (freq) { 714 default_interval = freq; 715 freq = 1; 716 } 717 718 /* CPU and PID are mutually exclusive */ 719 if (target_pid != -1 && profile_cpu != -1) { 720 printf("WARNING: PID switch overriding CPU\n"); 721 sleep(1); 722 profile_cpu = -1; 723 } 724 725 if (!nr_counters) 726 nr_counters = 1; 727 728 if (delay_secs < 1) 729 delay_secs = 1; 730 731 parse_symbols(); 732 733 /* 734 * Fill in the ones not specifically initialized via -c: 735 */ 736 for (counter = 0; counter < nr_counters; counter++) { 737 if (attrs[counter].sample_period) 738 continue; 739 740 attrs[counter].sample_period = default_interval; 741 } 742 743 nr_cpus = sysconf(_SC_NPROCESSORS_ONLN); 744 assert(nr_cpus <= MAX_NR_CPUS); 745 assert(nr_cpus >= 0); 746 747 if (target_pid != -1 || profile_cpu != -1) 748 nr_cpus = 1; 749 750 return __cmd_top(); 751 } 752