tools/perf/builtin-top.c

   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 #include <termios.h>
  35 #include <unistd.h>
  36
  37 #include <errno.h>
  38 #include <time.h>
  39 #include <sched.h>
  40 #include <pthread.h>
  41
  42 #include <sys/syscall.h>
  43 #include <sys/ioctl.h>
  44 #include <sys/poll.h>
  45 #include <sys/prctl.h>
  46 #include <sys/wait.h>
  47 #include <sys/uio.h>
  48 #include <sys/mman.h>
  49
  50 #include <linux/unistd.h>
  51 #include <linux/types.h>
  52
  53 static int                      fd[MAX_NR_CPUS][MAX_COUNTERS];
  54
  55 static int                      system_wide                     =  0;
  56
  57 static int                      default_interval                = 100000;
  58
  59 static int                      count_filter                    =  5;
  60 static int                      print_entries                   = 15;
  61
  62 static int                      target_pid                      = -1;
  63 static int                      inherit                         =  0;
  64 static int                      profile_cpu                     = -1;
  65 static int                      nr_cpus                         =  0;
  66 static unsigned int             realtime_prio                   =  0;
  67 static int                      group                           =  0;
  68 static unsigned int             page_size;
  69 static unsigned int             mmap_pages                      = 16;
  70 static int                      freq                            =  0;
  71 static int                      verbose                         =  0;
  72 static char                     *vmlinux                        =  NULL;
  73
  74 static int                      delay_secs                      =  2;
  75 static int                      zero;
  76 static int                      dump_symtab;
  77
  78 /*
  79  * Source
  80  */
  81
  82 struct source_line {
  83         u64                     eip;
  84         unsigned long           count[MAX_COUNTERS];
  85         char                    *line;
  86         struct source_line      *next;
  87 };
  88
  89 static char                     *sym_filter                     =  NULL;
  90 struct sym_entry                *sym_filter_entry               =  NULL;
  91 static int                      sym_pcnt_filter                 =  5;
  92 static int                      sym_counter                     =  0;
  93
  94 /*
  95  * Symbols
  96  */
  97
  98 static u64                      min_ip;
  99 static u64                      max_ip = -1ll;
 100
 101 struct sym_entry {
 102         struct rb_node          rb_node;
 103         struct list_head        node;
 104         unsigned long           count[MAX_COUNTERS];
 105         unsigned long           snap_count;
 106         double                  weight;
 107         int                     skip;
 108         struct source_line      *source;
 109         struct source_line      *lines;
 110         struct source_line      **lines_tail;
 111         pthread_mutex_t         source_lock;
 112 };
 113
 114 /*
 115  * Source functions
 116  */
 117
 118 static void parse_source(struct sym_entry *syme)
 119 {
 120         struct symbol *sym;
 121         struct module *module;
 122         struct section *section = NULL;
 123         FILE *file;
 124         char command[PATH_MAX*2], *path = vmlinux;
 125         u64 start, end, len;
 126
 127         if (!syme)
 128                 return;
 129
 130         if (syme->lines) {
 131                 pthread_mutex_lock(&syme->source_lock);
 132                 goto out_assign;
 133         }
 134
 135         sym = (struct symbol *)(syme + 1);
 136         module = sym->module;
 137
 138         if (module)
 139                 path = module->path;
 140         if (!path)
 141                 return;
 142
 143         start = sym->obj_start;
 144         if (!start)
 145                 start = sym->start;
 146
 147         if (module) {
 148                 section = module->sections->find_section(module->sections, ".text");
 149                 if (section)
 150                         start -= section->vma;
 151         }
 152
 153         end = start + sym->end - sym->start + 1;
 154         len = sym->end - sym->start;
 155
 156         sprintf(command, "objdump --start-address=0x%016Lx --stop-address=0x%016Lx -dS %s", start, end, path);
 157
 158         file = popen(command, "r");
 159         if (!file)
 160                 return;
 161
 162         pthread_mutex_lock(&syme->source_lock);
 163         syme->lines_tail = &syme->lines;
 164         while (!feof(file)) {
 165                 struct source_line *src;
 166                 size_t dummy = 0;
 167                 char *c;
 168
 169                 src = malloc(sizeof(struct source_line));
 170                 assert(src != NULL);
 171                 memset(src, 0, sizeof(struct source_line));
 172
 173                 if (getline(&src->line, &dummy, file) < 0)
 174                         break;
 175                 if (!src->line)
 176                         break;
 177
 178                 c = strchr(src->line, '\n');
 179                 if (c)
 180                         *c = 0;
 181
 182                 src->next = NULL;
 183                 *syme->lines_tail = src;
 184                 syme->lines_tail = &src->next;
 185
 186                 if (strlen(src->line)>8 && src->line[8] == ':') {
 187                         src->eip = strtoull(src->line, NULL, 16);
 188                         if (section)
 189                                 src->eip += section->vma;
 190                 }
 191                 if (strlen(src->line)>8 && src->line[16] == ':') {
 192                         src->eip = strtoull(src->line, NULL, 16);
 193                         if (section)
 194                                 src->eip += section->vma;
 195                 }
 196         }
 197         pclose(file);
 198 out_assign:
 199         sym_filter_entry = syme;
 200         pthread_mutex_unlock(&syme->source_lock);
 201 }
 202
 203 static void __zero_source_counters(struct sym_entry *syme)
 204 {
 205         int i;
 206         struct source_line *line;
 207
 208         line = syme->lines;
 209         while (line) {
 210                 for (i = 0; i < nr_counters; i++)
 211                         line->count[i] = 0;
 212                 line = line->next;
 213         }
 214 }
 215
 216 static void record_precise_ip(struct sym_entry *syme, int counter, u64 ip)
 217 {
 218         struct source_line *line;
 219
 220         if (syme != sym_filter_entry)
 221                 return;
 222
 223         if (pthread_mutex_trylock(&syme->source_lock))
 224                 return;
 225
 226         if (!syme->source)
 227                 goto out_unlock;
 228
 229         for (line = syme->lines; line; line = line->next) {
 230                 if (line->eip == ip) {
 231                         line->count[counter]++;
 232                         break;
 233                 }
 234                 if (line->eip > ip)
 235                         break;
 236         }
 237 out_unlock:
 238         pthread_mutex_unlock(&syme->source_lock);
 239 }
 240
 241 static void lookup_sym_source(struct sym_entry *syme)
 242 {
 243         struct symbol *symbol = (struct symbol *)(syme + 1);
 244         struct source_line *line;
 245         char pattern[PATH_MAX];
 246         char *idx;
 247
 248         sprintf(pattern, "<%s>:", symbol->name);
 249
 250         if (symbol->module) {
 251                 idx = strstr(pattern, "\t");
 252                 if (idx)
 253                         *idx = 0;
 254         }
 255
 256         pthread_mutex_lock(&syme->source_lock);
 257         for (line = syme->lines; line; line = line->next) {
 258                 if (strstr(line->line, pattern)) {
 259                         syme->source = line;
 260                         break;
 261                 }
 262         }
 263         pthread_mutex_unlock(&syme->source_lock);
 264 }
 265
 266 static void show_lines(struct source_line *queue, int count, int total)
 267 {
 268         int i;
 269         struct source_line *line;
 270
 271         line = queue;
 272         for (i = 0; i < count; i++) {
 273                 float pcnt = 100.0*(float)line->count[sym_counter]/(float)total;
 274
 275                 printf("%8li %4.1f%%\t%s\n", line->count[sym_counter], pcnt, line->line);
 276                 line = line->next;
 277         }
 278 }
 279
 280 #define TRACE_COUNT     3
 281
 282 static void show_details(struct sym_entry *syme)
 283 {
 284         struct symbol *symbol;
 285         struct source_line *line;
 286         struct source_line *line_queue = NULL;
 287         int displayed = 0;
 288         int line_queue_count = 0, total = 0, more = 0;
 289
 290         if (!syme)
 291                 return;
 292
 293         if (!syme->source)
 294                 lookup_sym_source(syme);
 295
 296         if (!syme->source)
 297                 return;
 298
 299         symbol = (struct symbol *)(syme + 1);
 300         printf("Showing %s for %s\n", event_name(sym_counter), symbol->name);
 301         printf("  Events  Pcnt (>=%d%%)\n", sym_pcnt_filter);
 302
 303         pthread_mutex_lock(&syme->source_lock);
 304         line = syme->source;
 305         while (line) {
 306                 total += line->count[sym_counter];
 307                 line = line->next;
 308         }
 309
 310         line = syme->source;
 311         while (line) {
 312                 float pcnt = 0.0;
 313
 314                 if (!line_queue_count)
 315                         line_queue = line;
 316                 line_queue_count++;
 317
 318                 if (line->count[sym_counter])
 319                         pcnt = 100.0 * line->count[sym_counter] / (float)total;
 320                 if (pcnt >= (float)sym_pcnt_filter) {
 321                         if (displayed <= print_entries)
 322                                 show_lines(line_queue, line_queue_count, total);
 323                         else more++;
 324                         displayed += line_queue_count;
 325                         line_queue_count = 0;
 326                         line_queue = NULL;
 327                 } else if (line_queue_count > TRACE_COUNT) {
 328                         line_queue = line_queue->next;
 329                         line_queue_count--;
 330                 }
 331
 332                 line->count[sym_counter] = zero ? 0 : line->count[sym_counter] * 7 / 8;
 333                 line = line->next;
 334         }
 335         pthread_mutex_unlock(&syme->source_lock);
 336         if (more)
 337                 printf("%d lines not displayed, maybe increase display entries [e]\n", more);
 338 }
 339
 340 struct dso                      *kernel_dso;
 341
 342 /*
 343  * Symbols will be added here in record_ip and will get out
 344  * after decayed.
 345  */
 346 static LIST_HEAD(active_symbols);
 347 static pthread_mutex_t active_symbols_lock = PTHREAD_MUTEX_INITIALIZER;
 348
 349 /*
 350  * Ordering weight: count-1 * count-2 * ... / count-n
 351  */
 352 static double sym_weight(const struct sym_entry *sym)
 353 {
 354         double weight = sym->snap_count;
 355         int counter;
 356
 357         for (counter = 1; counter < nr_counters-1; counter++)
 358                 weight *= sym->count[counter];
 359
 360         weight /= (sym->count[counter] + 1);
 361
 362         return weight;
 363 }
 364
 365 static long                     samples;
 366 static long                     userspace_samples;
 367 static const char               CONSOLE_CLEAR[] = "\e[H\e[2J";
 368
 369 static void __list_insert_active_sym(struct sym_entry *syme)
 370 {
 371         list_add(&syme->node, &active_symbols);
 372 }
 373
 374 static void list_remove_active_sym(struct sym_entry *syme)
 375 {
 376         pthread_mutex_lock(&active_symbols_lock);
 377         list_del_init(&syme->node);
 378         pthread_mutex_unlock(&active_symbols_lock);
 379 }
 380
 381 static void rb_insert_active_sym(struct rb_root *tree, struct sym_entry *se)
 382 {
 383         struct rb_node **p = &tree->rb_node;
 384         struct rb_node *parent = NULL;
 385         struct sym_entry *iter;
 386
 387         while (*p != NULL) {
 388                 parent = *p;
 389                 iter = rb_entry(parent, struct sym_entry, rb_node);
 390
 391                 if (se->weight > iter->weight)
 392                         p = &(*p)->rb_left;
 393                 else
 394                         p = &(*p)->rb_right;
 395         }
 396
 397         rb_link_node(&se->rb_node, parent, p);
 398         rb_insert_color(&se->rb_node, tree);
 399 }
 400
 401 static void print_sym_table(void)
 402 {
 403         int printed = 0, j;
 404         int counter;
 405         float samples_per_sec = samples/delay_secs;
 406         float ksamples_per_sec = (samples-userspace_samples)/delay_secs;
 407         float sum_ksamples = 0.0;
 408         struct sym_entry *syme, *n;
 409         struct rb_root tmp = RB_ROOT;
 410         struct rb_node *nd;
 411
 412         samples = userspace_samples = 0;
 413
 414         /* Sort the active symbols */
 415         pthread_mutex_lock(&active_symbols_lock);
 416         syme = list_entry(active_symbols.next, struct sym_entry, node);
 417         pthread_mutex_unlock(&active_symbols_lock);
 418
 419         list_for_each_entry_safe_from(syme, n, &active_symbols, node) {
 420                 syme->snap_count = syme->count[0];
 421                 if (syme->snap_count != 0) {
 422                         syme->weight = sym_weight(syme);
 423                         rb_insert_active_sym(&tmp, syme);
 424                         sum_ksamples += syme->snap_count;
 425
 426                         for (j = 0; j < nr_counters; j++)
 427                                 syme->count[j] = zero ? 0 : syme->count[j] * 7 / 8;
 428                 } else
 429                         list_remove_active_sym(syme);
 430         }
 431
 432         puts(CONSOLE_CLEAR);
 433
 434         printf(
 435 "------------------------------------------------------------------------------\n");
 436         printf( "   PerfTop:%8.0f irqs/sec  kernel:%4.1f%% [",
 437                 samples_per_sec,
 438                 100.0 - (100.0*((samples_per_sec-ksamples_per_sec)/samples_per_sec)));
 439
 440         if (nr_counters == 1) {
 441                 printf("%Ld", (u64)attrs[0].sample_period);
 442                 if (freq)
 443                         printf("Hz ");
 444                 else
 445                         printf(" ");
 446         }
 447
 448         for (counter = 0; counter < nr_counters; counter++) {
 449                 if (counter)
 450                         printf("/");
 451
 452                 printf("%s", event_name(counter));
 453         }
 454
 455         printf( "], ");
 456
 457         if (target_pid != -1)
 458                 printf(" (target_pid: %d", target_pid);
 459         else
 460                 printf(" (all");
 461
 462         if (profile_cpu != -1)
 463                 printf(", cpu: %d)\n", profile_cpu);
 464         else {
 465                 if (target_pid != -1)
 466                         printf(")\n");
 467                 else
 468                         printf(", %d CPUs)\n", nr_cpus);
 469         }
 470
 471         printf("------------------------------------------------------------------------------\n\n");
 472
 473         if (sym_filter_entry) {
 474                 show_details(sym_filter_entry);
 475                 return;
 476         }
 477
 478         if (nr_counters == 1)
 479                 printf("             samples    pcnt");
 480         else
 481                 printf("  weight     samples    pcnt");
 482
 483         printf("         RIP          kernel function\n"
 484                        "  ______     _______   _____   ________________   _______________\n\n"
 485         );
 486
 487         for (nd = rb_first(&tmp); nd; nd = rb_next(nd)) {
 488                 struct sym_entry *syme = rb_entry(nd, struct sym_entry, rb_node);
 489                 struct symbol *sym = (struct symbol *)(syme + 1);
 490                 double pcnt;
 491
 492                 if (++printed > print_entries || (int)syme->snap_count < count_filter)
 493                         continue;
 494
 495                 pcnt = 100.0 - (100.0 * ((sum_ksamples - syme->snap_count) /
 496                                          sum_ksamples));
 497
 498                 if (nr_counters == 1)
 499                         printf("%20.2f - ", syme->weight);
 500                 else
 501                         printf("%9.1f %10ld - ", syme->weight, syme->snap_count);
 502
 503                 percent_color_fprintf(stdout, "%4.1f%%", pcnt);
 504                 printf(" - %016llx : %s", sym->start, sym->name);
 505                 if (sym->module)
 506                         printf("\t[%s]", sym->module->name);
 507                 printf("\n");
 508         }
 509 }
 510
 511 static void prompt_integer(int *target, const char *msg)
 512 {
 513         char *buf = malloc(0), *p;
 514         size_t dummy = 0;
 515         int tmp;
 516
 517         fprintf(stdout, "\n%s: ", msg);
 518         if (getline(&buf, &dummy, stdin) < 0)
 519                 return;
 520
 521         p = strchr(buf, '\n');
 522         if (p)
 523                 *p = 0;
 524
 525         p = buf;
 526         while(*p) {
 527                 if (!isdigit(*p))
 528                         goto out_free;
 529                 p++;
 530         }
 531         tmp = strtoul(buf, NULL, 10);
 532         *target = tmp;
 533 out_free:
 534         free(buf);
 535 }
 536
 537 static void prompt_percent(int *target, const char *msg)
 538 {
 539         int tmp = 0;
 540
 541         prompt_integer(&tmp, msg);
 542         if (tmp >= 0 && tmp <= 100)
 543                 *target = tmp;
 544 }
 545
 546 static void prompt_symbol(struct sym_entry **target, const char *msg)
 547 {
 548         char *buf = malloc(0), *p;
 549         struct sym_entry *syme = *target, *n, *found = NULL;
 550         size_t dummy = 0;
 551
 552         /* zero counters of active symbol */
 553         if (syme) {
 554                 pthread_mutex_lock(&syme->source_lock);
 555                 __zero_source_counters(syme);
 556                 *target = NULL;
 557                 pthread_mutex_unlock(&syme->source_lock);
 558         }
 559
 560         fprintf(stdout, "\n%s: ", msg);
 561         if (getline(&buf, &dummy, stdin) < 0)
 562                 goto out_free;
 563
 564         p = strchr(buf, '\n');
 565         if (p)
 566                 *p = 0;
 567
 568         pthread_mutex_lock(&active_symbols_lock);
 569         syme = list_entry(active_symbols.next, struct sym_entry, node);
 570         pthread_mutex_unlock(&active_symbols_lock);
 571
 572         list_for_each_entry_safe_from(syme, n, &active_symbols, node) {
 573                 struct symbol *sym = (struct symbol *)(syme + 1);
 574
 575                 if (!strcmp(buf, sym->name)) {
 576                         found = syme;
 577                         break;
 578                 }
 579         }
 580
 581         if (!found) {
 582                 fprintf(stderr, "Sorry, %s is not active.\n", sym_filter);
 583                 sleep(1);
 584                 return;
 585         } else
 586                 parse_source(found);
 587
 588 out_free:
 589         free(buf);
 590 }
 591
 592 static void print_known_keys(void)
 593 {
 594         fprintf(stdout, "\nknown keys:\n");
 595         fprintf(stdout, "\t[d]     select display delay.\n");
 596         fprintf(stdout, "\t[e]     select display entries (lines).\n");
 597         fprintf(stdout, "\t[E]     select annotation event counter.\n");
 598         fprintf(stdout, "\t[f]     select normal display count filter.\n");
 599         fprintf(stdout, "\t[F]     select annotation display count filter (percentage).\n");
 600         fprintf(stdout, "\t[qQ]    quit.\n");
 601         fprintf(stdout, "\t[s]     select annotation symbol and start annotation.\n");
 602         fprintf(stdout, "\t[S]     stop annotation, revert to normal display.\n");
 603         fprintf(stdout, "\t[z]     toggle event count zeroing.\n");
 604 }
 605
 606 static void handle_keypress(int c)
 607 {
 608         int once = 0;
 609 repeat:
 610         switch (c) {
 611                 case 'd':
 612                         prompt_integer(&delay_secs, "Enter display delay");
 613                         break;
 614                 case 'e':
 615                         prompt_integer(&print_entries, "Enter display entries (lines)");
 616                         break;
 617                 case 'E':
 618                         if (nr_counters > 1) {
 619                                 int i;
 620
 621                                 fprintf(stderr, "\nAvailable events:");
 622                                 for (i = 0; i < nr_counters; i++)
 623                                         fprintf(stderr, "\n\t%d %s", i, event_name(i));
 624
 625                                 prompt_integer(&sym_counter, "Enter details event counter");
 626
 627                                 if (sym_counter >= nr_counters) {
 628                                         fprintf(stderr, "Sorry, no such event, using %s.\n", event_name(0));
 629                                         sym_counter = 0;
 630                                         sleep(1);
 631                                 }
 632                         } else sym_counter = 0;
 633                         break;
 634                 case 'f':
 635                         prompt_integer(&count_filter, "Enter display event count filter");
 636                         break;
 637                 case 'F':
 638                         prompt_percent(&sym_pcnt_filter, "Enter details display event filter (percent)");
 639                         break;
 640                 case 'q':
 641                 case 'Q':
 642                         printf("exiting.\n");
 643                         exit(0);
 644                 case 's':
 645                         prompt_symbol(&sym_filter_entry, "Enter details symbol");
 646                         break;
 647                 case 'S':
 648                         if (!sym_filter_entry)
 649                                 break;
 650                         else {
 651                                 struct sym_entry *syme = sym_filter_entry;
 652
 653                                 pthread_mutex_lock(&syme->source_lock);
 654                                 sym_filter_entry = NULL;
 655                                 __zero_source_counters(syme);
 656                                 pthread_mutex_unlock(&syme->source_lock);
 657                         }
 658                         break;
 659                 case 'z':
 660                         zero = ~zero;
 661                         break;
 662                 default: {
 663                         struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };
 664                         struct termios tc, save;
 665
 666                         if (!once) {
 667                                 print_known_keys();
 668                                 once++;
 669                         }
 670
 671                         tcgetattr(0, &save);
 672                         tc = save;
 673                         tc.c_lflag &= ~(ICANON | ECHO);
 674                         tc.c_cc[VMIN] = 0;
 675                         tc.c_cc[VTIME] = 0;
 676                         tcsetattr(0, TCSANOW, &tc);
 677
 678                         poll(&stdin_poll, 1, -1);
 679                         c = getc(stdin);
 680
 681                         tcsetattr(0, TCSAFLUSH, &save);
 682                         goto repeat;
 683                 }
 684         }
 685 }
 686
 687 static void *display_thread(void *arg __used)
 688 {
 689         struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };
 690         struct termios tc, save;
 691         int delay_msecs, c;
 692
 693         tcgetattr(0, &save);
 694         tc = save;
 695         tc.c_lflag &= ~(ICANON | ECHO);
 696         tc.c_cc[VMIN] = 0;
 697         tc.c_cc[VTIME] = 0;
 698 repeat:
 699         delay_msecs = delay_secs * 1000;
 700         tcsetattr(0, TCSANOW, &tc);
 701         /* trash return*/
 702         getc(stdin);
 703
 704         do {
 705                 print_sym_table();
 706         } while (!poll(&stdin_poll, 1, delay_msecs) == 1);
 707
 708         c = getc(stdin);
 709         tcsetattr(0, TCSAFLUSH, &save);
 710
 711         handle_keypress(c);
 712         goto repeat;
 713
 714         return NULL;
 715 }
 716
 717 /* Tag samples to be skipped. */
 718 static const char *skip_symbols[] = {
 719         "default_idle",
 720         "cpu_idle",
 721         "enter_idle",
 722         "exit_idle",
 723         "mwait_idle",
 724         "mwait_idle_with_hints",
 725         "ppc64_runlatch_off",
 726         "pseries_dedicated_idle_sleep",
 727         NULL
 728 };
 729
 730 static int symbol_filter(struct dso *self, struct symbol *sym)
 731 {
 732         struct sym_entry *syme;
 733         const char *name = sym->name;
 734         int i;
 735
 736         /*
 737          * ppc64 uses function descriptors and appends a '.' to the
 738          * start of every instruction address. Remove it.
 739          */
 740         if (name[0] == '.')
 741                 name++;
 742
 743         if (!strcmp(name, "_text") ||
 744             !strcmp(name, "_etext") ||
 745             !strcmp(name, "_sinittext") ||
 746             !strncmp("init_module", name, 11) ||
 747             !strncmp("cleanup_module", name, 14) ||
 748             strstr(name, "_text_start") ||
 749             strstr(name, "_text_end"))
 750                 return 1;
 751
 752         syme = dso__sym_priv(self, sym);
 753         pthread_mutex_init(&syme->source_lock, NULL);
 754         if (!sym_filter_entry && sym_filter && !strcmp(name, sym_filter))
 755                 sym_filter_entry = syme;
 756
 757         for (i = 0; skip_symbols[i]; i++) {
 758                 if (!strcmp(skip_symbols[i], name)) {
 759                         syme->skip = 1;
 760                         break;
 761                 }
 762         }
 763
 764         return 0;
 765 }
 766
 767 static int parse_symbols(void)
 768 {
 769         struct rb_node *node;
 770         struct symbol  *sym;
 771         int modules = vmlinux ? 1 : 0;
 772
 773         kernel_dso = dso__new("[kernel]", sizeof(struct sym_entry));
 774         if (kernel_dso == NULL)
 775                 return -1;
 776
 777         if (dso__load_kernel(kernel_dso, vmlinux, symbol_filter, verbose, modules) <= 0)
 778                 goto out_delete_dso;
 779
 780         node = rb_first(&kernel_dso->syms);
 781         sym = rb_entry(node, struct symbol, rb_node);
 782         min_ip = sym->start;
 783
 784         node = rb_last(&kernel_dso->syms);
 785         sym = rb_entry(node, struct symbol, rb_node);
 786         max_ip = sym->end;
 787
 788         if (dump_symtab)
 789                 dso__fprintf(kernel_dso, stderr);
 790
 791         return 0;
 792
 793 out_delete_dso:
 794         dso__delete(kernel_dso);
 795         kernel_dso = NULL;
 796         return -1;
 797 }
 798
 799 /*
 800  * Binary search in the histogram table and record the hit:
 801  */
 802 static void record_ip(u64 ip, int counter)
 803 {
 804         struct symbol *sym = dso__find_symbol(kernel_dso, ip);
 805
 806         if (sym != NULL) {
 807                 struct sym_entry *syme = dso__sym_priv(kernel_dso, sym);
 808
 809                 if (!syme->skip) {
 810                         syme->count[counter]++;
 811                         record_precise_ip(syme, counter, ip);
 812                         pthread_mutex_lock(&active_symbols_lock);
 813                         if (list_empty(&syme->node) || !syme->node.next)
 814                                 __list_insert_active_sym(syme);
 815                         pthread_mutex_unlock(&active_symbols_lock);
 816                         return;
 817                 }
 818         }
 819
 820         samples--;
 821 }
 822
 823 static void process_event(u64 ip, int counter, int user)
 824 {
 825         samples++;
 826
 827         if (user) {
 828                 userspace_samples++;
 829                 return;
 830         }
 831
 832         record_ip(ip, counter);
 833 }
 834
 835 struct mmap_data {
 836         int                     counter;
 837         void                    *base;
 838         int                     mask;
 839         unsigned int            prev;
 840 };
 841
 842 static unsigned int mmap_read_head(struct mmap_data *md)
 843 {
 844         struct perf_counter_mmap_page *pc = md->base;
 845         int head;
 846
 847         head = pc->data_head;
 848         rmb();
 849
 850         return head;
 851 }
 852
 853 struct timeval last_read, this_read;
 854
 855 static void mmap_read_counter(struct mmap_data *md)
 856 {
 857         unsigned int head = mmap_read_head(md);
 858         unsigned int old = md->prev;
 859         unsigned char *data = md->base + page_size;
 860         int diff;
 861
 862         gettimeofday(&this_read, NULL);
 863
 864         /*
 865          * If we're further behind than half the buffer, there's a chance
 866          * the writer will bite our tail and mess up the samples under us.
 867          *
 868          * If we somehow ended up ahead of the head, we got messed up.
 869          *
 870          * In either case, truncate and restart at head.
 871          */
 872         diff = head - old;
 873         if (diff > md->mask / 2 || diff < 0) {
 874                 struct timeval iv;
 875                 unsigned long msecs;
 876
 877                 timersub(&this_read, &last_read, &iv);
 878                 msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
 879
 880                 fprintf(stderr, "WARNING: failed to keep up with mmap data."
 881                                 "  Last read %lu msecs ago.\n", msecs);
 882
 883                 /*
 884                  * head points to a known good entry, start there.
 885                  */
 886                 old = head;
 887         }
 888
 889         last_read = this_read;
 890
 891         for (; old != head;) {
 892                 struct ip_event {
 893                         struct perf_event_header header;
 894                         u64 ip;
 895                         u32 pid, target_pid;
 896                 };
 897                 struct mmap_event {
 898                         struct perf_event_header header;
 899                         u32 pid, target_pid;
 900                         u64 start;
 901                         u64 len;
 902                         u64 pgoff;
 903                         char filename[PATH_MAX];
 904                 };
 905
 906                 typedef union event_union {
 907                         struct perf_event_header header;
 908                         struct ip_event ip;
 909                         struct mmap_event mmap;
 910                 } event_t;
 911
 912                 event_t *event = (event_t *)&data[old & md->mask];
 913
 914                 event_t event_copy;
 915
 916                 size_t size = event->header.size;
 917
 918                 /*
 919                  * Event straddles the mmap boundary -- header should always
 920                  * be inside due to u64 alignment of output.
 921                  */
 922                 if ((old & md->mask) + size != ((old + size) & md->mask)) {
 923                         unsigned int offset = old;
 924                         unsigned int len = min(sizeof(*event), size), cpy;
 925                         void *dst = &event_copy;
 926
 927                         do {
 928                                 cpy = min(md->mask + 1 - (offset & md->mask), len);
 929                                 memcpy(dst, &data[offset & md->mask], cpy);
 930                                 offset += cpy;
 931                                 dst += cpy;
 932                                 len -= cpy;
 933                         } while (len);
 934
 935                         event = &event_copy;
 936                 }
 937
 938                 old += size;
 939
 940                 if (event->header.type == PERF_EVENT_SAMPLE) {
 941                         int user =
 942         (event->header.misc & PERF_EVENT_MISC_CPUMODE_MASK) == PERF_EVENT_MISC_USER;
 943                         process_event(event->ip.ip, md->counter, user);
 944                 }
 945         }
 946
 947         md->prev = old;
 948 }
 949
 950 static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
 951 static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
 952
 953 static void mmap_read(void)
 954 {
 955         int i, counter;
 956
 957         for (i = 0; i < nr_cpus; i++) {
 958                 for (counter = 0; counter < nr_counters; counter++)
 959                         mmap_read_counter(&mmap_array[i][counter]);
 960         }
 961 }
 962
 963 int nr_poll;
 964 int group_fd;
 965
 966 static void start_counter(int i, int counter)
 967 {
 968         struct perf_counter_attr *attr;
 969         int cpu;
 970
 971         cpu = profile_cpu;
 972         if (target_pid == -1 && profile_cpu == -1)
 973                 cpu = i;
 974
 975         attr = attrs + counter;
 976
 977         attr->sample_type       = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
 978         attr->freq              = freq;
 979         attr->inherit           = (cpu < 0) && inherit;
 980
 981 try_again:
 982         fd[i][counter] = sys_perf_counter_open(attr, target_pid, cpu, group_fd, 0);
 983
 984         if (fd[i][counter] < 0) {
 985                 int err = errno;
 986
 987                 if (err == EPERM)
 988                         die("No permission - are you root?\n");
 989                 /*
 990                  * If it's cycles then fall back to hrtimer
 991                  * based cpu-clock-tick sw counter, which
 992                  * is always available even if no PMU support:
 993                  */
 994                 if (attr->type == PERF_TYPE_HARDWARE
 995                         && attr->config == PERF_COUNT_HW_CPU_CYCLES) {
 996
 997                         if (verbose)
 998                                 warning(" ... trying to fall back to cpu-clock-ticks\n");
 999
1000                         attr->type = PERF_TYPE_SOFTWARE;
1001                         attr->config = PERF_COUNT_SW_CPU_CLOCK;
1002                         goto try_again;
1003                 }
1004                 printf("\n");
1005                 error("perfcounter syscall returned with %d (%s)\n",
1006                         fd[i][counter], strerror(err));
1007                 die("No CONFIG_PERF_COUNTERS=y kernel support configured?\n");
1008                 exit(-1);
1009         }
1010         assert(fd[i][counter] >= 0);
1011         fcntl(fd[i][counter], F_SETFL, O_NONBLOCK);
1012
1013         /*
1014          * First counter acts as the group leader:
1015          */
1016         if (group && group_fd == -1)
1017                 group_fd = fd[i][counter];
1018
1019         event_array[nr_poll].fd = fd[i][counter];
1020         event_array[nr_poll].events = POLLIN;
1021         nr_poll++;
1022
1023         mmap_array[i][counter].counter = counter;
1024         mmap_array[i][counter].prev = 0;
1025         mmap_array[i][counter].mask = mmap_pages*page_size - 1;
1026         mmap_array[i][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
1027                         PROT_READ, MAP_SHARED, fd[i][counter], 0);
1028         if (mmap_array[i][counter].base == MAP_FAILED)
1029                 die("failed to mmap with %d (%s)\n", errno, strerror(errno));
1030 }
1031
1032 static int __cmd_top(void)
1033 {
1034         pthread_t thread;
1035         int i, counter;
1036         int ret;
1037
1038         for (i = 0; i < nr_cpus; i++) {
1039                 group_fd = -1;
1040                 for (counter = 0; counter < nr_counters; counter++)
1041                         start_counter(i, counter);
1042         }
1043
1044         /* Wait for a minimal set of events before starting the snapshot */
1045         poll(event_array, nr_poll, 100);
1046
1047         mmap_read();
1048
1049         if (pthread_create(&thread, NULL, display_thread, NULL)) {
1050                 printf("Could not create display thread.\n");
1051                 exit(-1);
1052         }
1053
1054         if (realtime_prio) {
1055                 struct sched_param param;
1056
1057                 param.sched_priority = realtime_prio;
1058                 if (sched_setscheduler(0, SCHED_FIFO, &param)) {
1059                         printf("Could not set realtime priority.\n");
1060                         exit(-1);
1061                 }
1062         }
1063
1064         while (1) {
1065                 int hits = samples;
1066
1067                 mmap_read();
1068
1069                 if (hits == samples)
1070                         ret = poll(event_array, nr_poll, 100);
1071         }
1072
1073         return 0;
1074 }
1075
1076 static const char * const top_usage[] = {
1077         "perf top [<options>]",
1078         NULL
1079 };
1080
1081 static const struct option options[] = {
1082         OPT_CALLBACK('e', "event", NULL, "event",
1083                      "event selector. use 'perf list' to list available events",
1084                      parse_events),
1085         OPT_INTEGER('c', "count", &default_interval,
1086                     "event period to sample"),
1087         OPT_INTEGER('p', "pid", &target_pid,
1088                     "profile events on existing pid"),
1089         OPT_BOOLEAN('a', "all-cpus", &system_wide,
1090                             "system-wide collection from all CPUs"),
1091         OPT_INTEGER('C', "CPU", &profile_cpu,
1092                     "CPU to profile on"),
1093         OPT_STRING('k', "vmlinux", &vmlinux, "file", "vmlinux pathname"),
1094         OPT_INTEGER('m', "mmap-pages", &mmap_pages,
1095                     "number of mmap data pages"),
1096         OPT_INTEGER('r', "realtime", &realtime_prio,
1097                     "collect data with this RT SCHED_FIFO priority"),
1098         OPT_INTEGER('d', "delay", &delay_secs,
1099                     "number of seconds to delay between refreshes"),
1100         OPT_BOOLEAN('D', "dump-symtab", &dump_symtab,
1101                             "dump the symbol table used for profiling"),
1102         OPT_INTEGER('f', "count-filter", &count_filter,
1103                     "only display functions with more events than this"),
1104         OPT_BOOLEAN('g', "group", &group,
1105                             "put the counters into a counter group"),
1106         OPT_BOOLEAN('i', "inherit", &inherit,
1107                     "child tasks inherit counters"),
1108         OPT_STRING('s', "sym-annotate", &sym_filter, "symbol name",
1109                     "symbol to annotate - requires -k option"),
1110         OPT_BOOLEAN('z', "zero", &zero,
1111                     "zero history across updates"),
1112         OPT_INTEGER('F', "freq", &freq,
1113                     "profile at this frequency"),
1114         OPT_INTEGER('E', "entries", &print_entries,
1115                     "display this many functions"),
1116         OPT_BOOLEAN('v', "verbose", &verbose,
1117                     "be more verbose (show counter open errors, etc)"),
1118         OPT_END()
1119 };
1120
1121 int cmd_top(int argc, const char **argv, const char *prefix __used)
1122 {
1123         int counter;
1124
1125         symbol__init();
1126
1127         page_size = sysconf(_SC_PAGE_SIZE);
1128
1129         argc = parse_options(argc, argv, options, top_usage, 0);
1130         if (argc)
1131                 usage_with_options(top_usage, options);
1132
1133         if (freq) {
1134                 default_interval = freq;
1135                 freq = 1;
1136         }
1137
1138         /* CPU and PID are mutually exclusive */
1139         if (target_pid != -1 && profile_cpu != -1) {
1140                 printf("WARNING: PID switch overriding CPU\n");
1141                 sleep(1);
1142                 profile_cpu = -1;
1143         }
1144
1145         if (!nr_counters)
1146                 nr_counters = 1;
1147
1148         if (delay_secs < 1)
1149                 delay_secs = 1;
1150
1151         parse_symbols();
1152         parse_source(sym_filter_entry);
1153
1154         /*
1155          * Fill in the ones not specifically initialized via -c:
1156          */
1157         for (counter = 0; counter < nr_counters; counter++) {
1158                 if (attrs[counter].sample_period)
1159                         continue;
1160
1161                 attrs[counter].sample_period = default_interval;
1162         }
1163
1164         nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
1165         assert(nr_cpus <= MAX_NR_CPUS);
1166         assert(nr_cpus >= 0);
1167
1168         if (target_pid != -1 || profile_cpu != -1)
1169                 nr_cpus = 1;
1170
1171         return __cmd_top();
1172 }