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 inherit = 0; 62 static int profile_cpu = -1; 63 static int nr_cpus = 0; 64 static unsigned int realtime_prio = 0; 65 static int group = 0; 66 static unsigned int page_size; 67 static unsigned int mmap_pages = 16; 68 static int freq = 0; 69 static int verbose = 0; 70 static char *vmlinux = NULL; 71 72 static char *sym_filter; 73 static unsigned long filter_start; 74 static unsigned long filter_end; 75 76 static int delay_secs = 2; 77 static int zero; 78 static int dump_symtab; 79 80 /* 81 * Symbols 82 */ 83 84 static u64 min_ip; 85 static u64 max_ip = -1ll; 86 87 struct sym_entry { 88 struct rb_node rb_node; 89 struct list_head node; 90 unsigned long count[MAX_COUNTERS]; 91 unsigned long snap_count; 92 double weight; 93 int skip; 94 }; 95 96 struct sym_entry *sym_filter_entry; 97 98 struct dso *kernel_dso; 99 100 /* 101 * Symbols will be added here in record_ip and will get out 102 * after decayed. 103 */ 104 static LIST_HEAD(active_symbols); 105 static pthread_mutex_t active_symbols_lock = PTHREAD_MUTEX_INITIALIZER; 106 107 /* 108 * Ordering weight: count-1 * count-2 * ... / count-n 109 */ 110 static double sym_weight(const struct sym_entry *sym) 111 { 112 double weight = sym->snap_count; 113 int counter; 114 115 for (counter = 1; counter < nr_counters-1; counter++) 116 weight *= sym->count[counter]; 117 118 weight /= (sym->count[counter] + 1); 119 120 return weight; 121 } 122 123 static long samples; 124 static long userspace_samples; 125 static const char CONSOLE_CLEAR[] = "[H[2J"; 126 127 static void __list_insert_active_sym(struct sym_entry *syme) 128 { 129 list_add(&syme->node, &active_symbols); 130 } 131 132 static void list_remove_active_sym(struct sym_entry *syme) 133 { 134 pthread_mutex_lock(&active_symbols_lock); 135 list_del_init(&syme->node); 136 pthread_mutex_unlock(&active_symbols_lock); 137 } 138 139 static void rb_insert_active_sym(struct rb_root *tree, struct sym_entry *se) 140 { 141 struct rb_node **p = &tree->rb_node; 142 struct rb_node *parent = NULL; 143 struct sym_entry *iter; 144 145 while (*p != NULL) { 146 parent = *p; 147 iter = rb_entry(parent, struct sym_entry, rb_node); 148 149 if (se->weight > iter->weight) 150 p = &(*p)->rb_left; 151 else 152 p = &(*p)->rb_right; 153 } 154 155 rb_link_node(&se->rb_node, parent, p); 156 rb_insert_color(&se->rb_node, tree); 157 } 158 159 static void print_sym_table(void) 160 { 161 int printed = 0, j; 162 int counter; 163 float samples_per_sec = samples/delay_secs; 164 float ksamples_per_sec = (samples-userspace_samples)/delay_secs; 165 float sum_ksamples = 0.0; 166 struct sym_entry *syme, *n; 167 struct rb_root tmp = RB_ROOT; 168 struct rb_node *nd; 169 170 samples = userspace_samples = 0; 171 172 /* Sort the active symbols */ 173 pthread_mutex_lock(&active_symbols_lock); 174 syme = list_entry(active_symbols.next, struct sym_entry, node); 175 pthread_mutex_unlock(&active_symbols_lock); 176 177 list_for_each_entry_safe_from(syme, n, &active_symbols, node) { 178 syme->snap_count = syme->count[0]; 179 if (syme->snap_count != 0) { 180 syme->weight = sym_weight(syme); 181 rb_insert_active_sym(&tmp, syme); 182 sum_ksamples += syme->snap_count; 183 184 for (j = 0; j < nr_counters; j++) 185 syme->count[j] = zero ? 0 : syme->count[j] * 7 / 8; 186 } else 187 list_remove_active_sym(syme); 188 } 189 190 puts(CONSOLE_CLEAR); 191 192 printf( 193 "------------------------------------------------------------------------------\n"); 194 printf( " PerfTop:%8.0f irqs/sec kernel:%4.1f%% [", 195 samples_per_sec, 196 100.0 - (100.0*((samples_per_sec-ksamples_per_sec)/samples_per_sec))); 197 198 if (nr_counters == 1) { 199 printf("%Ld", (u64)attrs[0].sample_period); 200 if (freq) 201 printf("Hz "); 202 else 203 printf(" "); 204 } 205 206 for (counter = 0; counter < nr_counters; counter++) { 207 if (counter) 208 printf("/"); 209 210 printf("%s", event_name(counter)); 211 } 212 213 printf( "], "); 214 215 if (target_pid != -1) 216 printf(" (target_pid: %d", target_pid); 217 else 218 printf(" (all"); 219 220 if (profile_cpu != -1) 221 printf(", cpu: %d)\n", profile_cpu); 222 else { 223 if (target_pid != -1) 224 printf(")\n"); 225 else 226 printf(", %d CPUs)\n", nr_cpus); 227 } 228 229 printf("------------------------------------------------------------------------------\n\n"); 230 231 if (nr_counters == 1) 232 printf(" samples pcnt"); 233 else 234 printf(" weight samples pcnt"); 235 236 printf(" RIP kernel function\n" 237 " ______ _______ _____ ________________ _______________\n\n" 238 ); 239 240 for (nd = rb_first(&tmp); nd; nd = rb_next(nd)) { 241 struct sym_entry *syme = rb_entry(nd, struct sym_entry, rb_node); 242 struct symbol *sym = (struct symbol *)(syme + 1); 243 double pcnt; 244 245 if (++printed > print_entries || syme->snap_count < count_filter) 246 continue; 247 248 pcnt = 100.0 - (100.0 * ((sum_ksamples - syme->snap_count) / 249 sum_ksamples)); 250 251 if (nr_counters == 1) 252 printf("%20.2f - ", syme->weight); 253 else 254 printf("%9.1f %10ld - ", syme->weight, syme->snap_count); 255 256 percent_color_fprintf(stdout, "%4.1f%%", pcnt); 257 printf(" - %016llx : %s", sym->start, sym->name); 258 if (sym->module) 259 printf("\t[%s]", sym->module->name); 260 printf("\n"); 261 } 262 } 263 264 static void *display_thread(void *arg __used) 265 { 266 struct pollfd stdin_poll = { .fd = 0, .events = POLLIN }; 267 int delay_msecs = delay_secs * 1000; 268 269 printf("PerfTop refresh period: %d seconds\n", delay_secs); 270 271 do { 272 print_sym_table(); 273 } while (!poll(&stdin_poll, 1, delay_msecs) == 1); 274 275 printf("key pressed - exiting.\n"); 276 exit(0); 277 278 return NULL; 279 } 280 281 /* Tag samples to be skipped. */ 282 static const char *skip_symbols[] = { 283 "default_idle", 284 "cpu_idle", 285 "enter_idle", 286 "exit_idle", 287 "mwait_idle", 288 "ppc64_runlatch_off", 289 "pseries_dedicated_idle_sleep", 290 NULL 291 }; 292 293 static int symbol_filter(struct dso *self, struct symbol *sym) 294 { 295 static int filter_match; 296 struct sym_entry *syme; 297 const char *name = sym->name; 298 int i; 299 300 /* 301 * ppc64 uses function descriptors and appends a '.' to the 302 * start of every instruction address. Remove it. 303 */ 304 if (name[0] == '.') 305 name++; 306 307 if (!strcmp(name, "_text") || 308 !strcmp(name, "_etext") || 309 !strcmp(name, "_sinittext") || 310 !strncmp("init_module", name, 11) || 311 !strncmp("cleanup_module", name, 14) || 312 strstr(name, "_text_start") || 313 strstr(name, "_text_end")) 314 return 1; 315 316 syme = dso__sym_priv(self, sym); 317 for (i = 0; skip_symbols[i]; i++) { 318 if (!strcmp(skip_symbols[i], name)) { 319 syme->skip = 1; 320 break; 321 } 322 } 323 324 if (filter_match == 1) { 325 filter_end = sym->start; 326 filter_match = -1; 327 if (filter_end - filter_start > 10000) { 328 fprintf(stderr, 329 "hm, too large filter symbol <%s> - skipping.\n", 330 sym_filter); 331 fprintf(stderr, "symbol filter start: %016lx\n", 332 filter_start); 333 fprintf(stderr, " end: %016lx\n", 334 filter_end); 335 filter_end = filter_start = 0; 336 sym_filter = NULL; 337 sleep(1); 338 } 339 } 340 341 if (filter_match == 0 && sym_filter && !strcmp(name, sym_filter)) { 342 filter_match = 1; 343 filter_start = sym->start; 344 } 345 346 347 return 0; 348 } 349 350 static int parse_symbols(void) 351 { 352 struct rb_node *node; 353 struct symbol *sym; 354 int modules = vmlinux ? 1 : 0; 355 356 kernel_dso = dso__new("[kernel]", sizeof(struct sym_entry)); 357 if (kernel_dso == NULL) 358 return -1; 359 360 if (dso__load_kernel(kernel_dso, vmlinux, symbol_filter, verbose, modules) <= 0) 361 goto out_delete_dso; 362 363 node = rb_first(&kernel_dso->syms); 364 sym = rb_entry(node, struct symbol, rb_node); 365 min_ip = sym->start; 366 367 node = rb_last(&kernel_dso->syms); 368 sym = rb_entry(node, struct symbol, rb_node); 369 max_ip = sym->end; 370 371 if (dump_symtab) 372 dso__fprintf(kernel_dso, stderr); 373 374 return 0; 375 376 out_delete_dso: 377 dso__delete(kernel_dso); 378 kernel_dso = NULL; 379 return -1; 380 } 381 382 #define TRACE_COUNT 3 383 384 /* 385 * Binary search in the histogram table and record the hit: 386 */ 387 static void record_ip(u64 ip, int counter) 388 { 389 struct symbol *sym = dso__find_symbol(kernel_dso, ip); 390 391 if (sym != NULL) { 392 struct sym_entry *syme = dso__sym_priv(kernel_dso, sym); 393 394 if (!syme->skip) { 395 syme->count[counter]++; 396 pthread_mutex_lock(&active_symbols_lock); 397 if (list_empty(&syme->node) || !syme->node.next) 398 __list_insert_active_sym(syme); 399 pthread_mutex_unlock(&active_symbols_lock); 400 return; 401 } 402 } 403 404 samples--; 405 } 406 407 static void process_event(u64 ip, int counter, int user) 408 { 409 samples++; 410 411 if (user) { 412 userspace_samples++; 413 return; 414 } 415 416 record_ip(ip, counter); 417 } 418 419 struct mmap_data { 420 int counter; 421 void *base; 422 int mask; 423 unsigned int prev; 424 }; 425 426 static unsigned int mmap_read_head(struct mmap_data *md) 427 { 428 struct perf_counter_mmap_page *pc = md->base; 429 int head; 430 431 head = pc->data_head; 432 rmb(); 433 434 return head; 435 } 436 437 struct timeval last_read, this_read; 438 439 static void mmap_read_counter(struct mmap_data *md) 440 { 441 unsigned int head = mmap_read_head(md); 442 unsigned int old = md->prev; 443 unsigned char *data = md->base + page_size; 444 int diff; 445 446 gettimeofday(&this_read, NULL); 447 448 /* 449 * If we're further behind than half the buffer, there's a chance 450 * the writer will bite our tail and mess up the samples under us. 451 * 452 * If we somehow ended up ahead of the head, we got messed up. 453 * 454 * In either case, truncate and restart at head. 455 */ 456 diff = head - old; 457 if (diff > md->mask / 2 || diff < 0) { 458 struct timeval iv; 459 unsigned long msecs; 460 461 timersub(&this_read, &last_read, &iv); 462 msecs = iv.tv_sec*1000 + iv.tv_usec/1000; 463 464 fprintf(stderr, "WARNING: failed to keep up with mmap data." 465 " Last read %lu msecs ago.\n", msecs); 466 467 /* 468 * head points to a known good entry, start there. 469 */ 470 old = head; 471 } 472 473 last_read = this_read; 474 475 for (; old != head;) { 476 struct ip_event { 477 struct perf_event_header header; 478 u64 ip; 479 u32 pid, target_pid; 480 }; 481 struct mmap_event { 482 struct perf_event_header header; 483 u32 pid, target_pid; 484 u64 start; 485 u64 len; 486 u64 pgoff; 487 char filename[PATH_MAX]; 488 }; 489 490 typedef union event_union { 491 struct perf_event_header header; 492 struct ip_event ip; 493 struct mmap_event mmap; 494 } event_t; 495 496 event_t *event = (event_t *)&data[old & md->mask]; 497 498 event_t event_copy; 499 500 size_t size = event->header.size; 501 502 /* 503 * Event straddles the mmap boundary -- header should always 504 * be inside due to u64 alignment of output. 505 */ 506 if ((old & md->mask) + size != ((old + size) & md->mask)) { 507 unsigned int offset = old; 508 unsigned int len = min(sizeof(*event), size), cpy; 509 void *dst = &event_copy; 510 511 do { 512 cpy = min(md->mask + 1 - (offset & md->mask), len); 513 memcpy(dst, &data[offset & md->mask], cpy); 514 offset += cpy; 515 dst += cpy; 516 len -= cpy; 517 } while (len); 518 519 event = &event_copy; 520 } 521 522 old += size; 523 524 if (event->header.type == PERF_EVENT_SAMPLE) { 525 int user = 526 (event->header.misc & PERF_EVENT_MISC_CPUMODE_MASK) == PERF_EVENT_MISC_USER; 527 process_event(event->ip.ip, md->counter, user); 528 } 529 } 530 531 md->prev = old; 532 } 533 534 static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS]; 535 static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS]; 536 537 static void mmap_read(void) 538 { 539 int i, counter; 540 541 for (i = 0; i < nr_cpus; i++) { 542 for (counter = 0; counter < nr_counters; counter++) 543 mmap_read_counter(&mmap_array[i][counter]); 544 } 545 } 546 547 int nr_poll; 548 int group_fd; 549 550 static void start_counter(int i, int counter) 551 { 552 struct perf_counter_attr *attr; 553 int cpu; 554 555 cpu = profile_cpu; 556 if (target_pid == -1 && profile_cpu == -1) 557 cpu = i; 558 559 attr = attrs + counter; 560 561 attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID; 562 attr->freq = freq; 563 attr->inherit = (cpu < 0) && inherit; 564 565 try_again: 566 fd[i][counter] = sys_perf_counter_open(attr, target_pid, cpu, group_fd, 0); 567 568 if (fd[i][counter] < 0) { 569 int err = errno; 570 571 if (err == EPERM) 572 die("No permission - are you root?\n"); 573 /* 574 * If it's cycles then fall back to hrtimer 575 * based cpu-clock-tick sw counter, which 576 * is always available even if no PMU support: 577 */ 578 if (attr->type == PERF_TYPE_HARDWARE 579 && attr->config == PERF_COUNT_HW_CPU_CYCLES) { 580 581 if (verbose) 582 warning(" ... trying to fall back to cpu-clock-ticks\n"); 583 584 attr->type = PERF_TYPE_SOFTWARE; 585 attr->config = PERF_COUNT_SW_CPU_CLOCK; 586 goto try_again; 587 } 588 printf("\n"); 589 error("perfcounter syscall returned with %d (%s)\n", 590 fd[i][counter], strerror(err)); 591 die("No CONFIG_PERF_COUNTERS=y kernel support configured?\n"); 592 exit(-1); 593 } 594 assert(fd[i][counter] >= 0); 595 fcntl(fd[i][counter], F_SETFL, O_NONBLOCK); 596 597 /* 598 * First counter acts as the group leader: 599 */ 600 if (group && group_fd == -1) 601 group_fd = fd[i][counter]; 602 603 event_array[nr_poll].fd = fd[i][counter]; 604 event_array[nr_poll].events = POLLIN; 605 nr_poll++; 606 607 mmap_array[i][counter].counter = counter; 608 mmap_array[i][counter].prev = 0; 609 mmap_array[i][counter].mask = mmap_pages*page_size - 1; 610 mmap_array[i][counter].base = mmap(NULL, (mmap_pages+1)*page_size, 611 PROT_READ, MAP_SHARED, fd[i][counter], 0); 612 if (mmap_array[i][counter].base == MAP_FAILED) 613 die("failed to mmap with %d (%s)\n", errno, strerror(errno)); 614 } 615 616 static int __cmd_top(void) 617 { 618 pthread_t thread; 619 int i, counter; 620 int ret; 621 622 for (i = 0; i < nr_cpus; i++) { 623 group_fd = -1; 624 for (counter = 0; counter < nr_counters; counter++) 625 start_counter(i, counter); 626 } 627 628 /* Wait for a minimal set of events before starting the snapshot */ 629 poll(event_array, nr_poll, 100); 630 631 mmap_read(); 632 633 if (pthread_create(&thread, NULL, display_thread, NULL)) { 634 printf("Could not create display thread.\n"); 635 exit(-1); 636 } 637 638 if (realtime_prio) { 639 struct sched_param param; 640 641 param.sched_priority = realtime_prio; 642 if (sched_setscheduler(0, SCHED_FIFO, ¶m)) { 643 printf("Could not set realtime priority.\n"); 644 exit(-1); 645 } 646 } 647 648 while (1) { 649 int hits = samples; 650 651 mmap_read(); 652 653 if (hits == samples) 654 ret = poll(event_array, nr_poll, 100); 655 } 656 657 return 0; 658 } 659 660 static const char * const top_usage[] = { 661 "perf top [<options>]", 662 NULL 663 }; 664 665 static const struct option options[] = { 666 OPT_CALLBACK('e', "event", NULL, "event", 667 "event selector. use 'perf list' to list available events", 668 parse_events), 669 OPT_INTEGER('c', "count", &default_interval, 670 "event period to sample"), 671 OPT_INTEGER('p', "pid", &target_pid, 672 "profile events on existing pid"), 673 OPT_BOOLEAN('a', "all-cpus", &system_wide, 674 "system-wide collection from all CPUs"), 675 OPT_INTEGER('C', "CPU", &profile_cpu, 676 "CPU to profile on"), 677 OPT_STRING('k', "vmlinux", &vmlinux, "file", "vmlinux pathname"), 678 OPT_INTEGER('m', "mmap-pages", &mmap_pages, 679 "number of mmap data pages"), 680 OPT_INTEGER('r', "realtime", &realtime_prio, 681 "collect data with this RT SCHED_FIFO priority"), 682 OPT_INTEGER('d', "delay", &delay_secs, 683 "number of seconds to delay between refreshes"), 684 OPT_BOOLEAN('D', "dump-symtab", &dump_symtab, 685 "dump the symbol table used for profiling"), 686 OPT_INTEGER('f', "count-filter", &count_filter, 687 "only display functions with more events than this"), 688 OPT_BOOLEAN('g', "group", &group, 689 "put the counters into a counter group"), 690 OPT_BOOLEAN('i', "inherit", &inherit, 691 "child tasks inherit counters"), 692 OPT_STRING('s', "sym-filter", &sym_filter, "pattern", 693 "only display symbols matchig this pattern"), 694 OPT_BOOLEAN('z', "zero", &zero, 695 "zero history across updates"), 696 OPT_INTEGER('F', "freq", &freq, 697 "profile at this frequency"), 698 OPT_INTEGER('E', "entries", &print_entries, 699 "display this many functions"), 700 OPT_BOOLEAN('v', "verbose", &verbose, 701 "be more verbose (show counter open errors, etc)"), 702 OPT_END() 703 }; 704 705 int cmd_top(int argc, const char **argv, const char *prefix __used) 706 { 707 int counter; 708 709 symbol__init(); 710 711 page_size = sysconf(_SC_PAGE_SIZE); 712 713 argc = parse_options(argc, argv, options, top_usage, 0); 714 if (argc) 715 usage_with_options(top_usage, options); 716 717 if (freq) { 718 default_interval = freq; 719 freq = 1; 720 } 721 722 /* CPU and PID are mutually exclusive */ 723 if (target_pid != -1 && profile_cpu != -1) { 724 printf("WARNING: PID switch overriding CPU\n"); 725 sleep(1); 726 profile_cpu = -1; 727 } 728 729 if (!nr_counters) 730 nr_counters = 1; 731 732 if (delay_secs < 1) 733 delay_secs = 1; 734 735 parse_symbols(); 736 737 /* 738 * Fill in the ones not specifically initialized via -c: 739 */ 740 for (counter = 0; counter < nr_counters; counter++) { 741 if (attrs[counter].sample_period) 742 continue; 743 744 attrs[counter].sample_period = default_interval; 745 } 746 747 nr_cpus = sysconf(_SC_NPROCESSORS_ONLN); 748 assert(nr_cpus <= MAX_NR_CPUS); 749 assert(nr_cpus >= 0); 750 751 if (target_pid != -1 || profile_cpu != -1) 752 nr_cpus = 1; 753 754 return __cmd_top(); 755 } 756