linux/tools/perf/builtin-top.c
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   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 "util/debug.h"
  31
  32#include <assert.h>
  33#include <fcntl.h>
  34
  35#include <stdio.h>
  36#include <termios.h>
  37#include <unistd.h>
  38
  39#include <errno.h>
  40#include <time.h>
  41#include <sched.h>
  42#include <pthread.h>
  43
  44#include <sys/syscall.h>
  45#include <sys/ioctl.h>
  46#include <sys/poll.h>
  47#include <sys/prctl.h>
  48#include <sys/wait.h>
  49#include <sys/uio.h>
  50#include <sys/mman.h>
  51
  52#include <linux/unistd.h>
  53#include <linux/types.h>
  54
  55static int                      fd[MAX_NR_CPUS][MAX_COUNTERS];
  56
  57static int                      system_wide                     =  0;
  58
  59static int                      default_interval                = 100000;
  60
  61static int                      count_filter                    =  5;
  62static int                      print_entries                   = 15;
  63
  64static int                      target_pid                      = -1;
  65static int                      inherit                         =  0;
  66static int                      profile_cpu                     = -1;
  67static int                      nr_cpus                         =  0;
  68static unsigned int             realtime_prio                   =  0;
  69static int                      group                           =  0;
  70static unsigned int             page_size;
  71static unsigned int             mmap_pages                      = 16;
  72static int                      freq                            =  0;
  73
  74static int                      delay_secs                      =  2;
  75static int                      zero;
  76static int                      dump_symtab;
  77
  78/*
  79 * Source
  80 */
  81
  82struct source_line {
  83        u64                     eip;
  84        unsigned long           count[MAX_COUNTERS];
  85        char                    *line;
  86        struct source_line      *next;
  87};
  88
  89static char                     *sym_filter                     =  NULL;
  90struct sym_entry                *sym_filter_entry               =  NULL;
  91static int                      sym_pcnt_filter                 =  5;
  92static int                      sym_counter                     =  0;
  93static int                      display_weighted                = -1;
  94
  95/*
  96 * Symbols
  97 */
  98
  99static u64                      min_ip;
 100static u64                      max_ip = -1ll;
 101
 102struct sym_entry {
 103        struct rb_node          rb_node;
 104        struct list_head        node;
 105        unsigned long           count[MAX_COUNTERS];
 106        unsigned long           snap_count;
 107        double                  weight;
 108        int                     skip;
 109        struct source_line      *source;
 110        struct source_line      *lines;
 111        struct source_line      **lines_tail;
 112        pthread_mutex_t         source_lock;
 113};
 114
 115/*
 116 * Source functions
 117 */
 118
 119static void parse_source(struct sym_entry *syme)
 120{
 121        struct symbol *sym;
 122        struct module *module;
 123        struct section *section = NULL;
 124        FILE *file;
 125        char command[PATH_MAX*2];
 126        const char *path = vmlinux_name;
 127        u64 start, end, len;
 128
 129        if (!syme)
 130                return;
 131
 132        if (syme->lines) {
 133                pthread_mutex_lock(&syme->source_lock);
 134                goto out_assign;
 135        }
 136
 137        sym = (struct symbol *)(syme + 1);
 138        module = sym->module;
 139
 140        if (module)
 141                path = module->path;
 142        if (!path)
 143                return;
 144
 145        start = sym->obj_start;
 146        if (!start)
 147                start = sym->start;
 148
 149        if (module) {
 150                section = module->sections->find_section(module->sections, ".text");
 151                if (section)
 152                        start -= section->vma;
 153        }
 154
 155        end = start + sym->end - sym->start + 1;
 156        len = sym->end - sym->start;
 157
 158        sprintf(command, "objdump --start-address=0x%016Lx --stop-address=0x%016Lx -dS %s", start, end, path);
 159
 160        file = popen(command, "r");
 161        if (!file)
 162                return;
 163
 164        pthread_mutex_lock(&syme->source_lock);
 165        syme->lines_tail = &syme->lines;
 166        while (!feof(file)) {
 167                struct source_line *src;
 168                size_t dummy = 0;
 169                char *c;
 170
 171                src = malloc(sizeof(struct source_line));
 172                assert(src != NULL);
 173                memset(src, 0, sizeof(struct source_line));
 174
 175                if (getline(&src->line, &dummy, file) < 0)
 176                        break;
 177                if (!src->line)
 178                        break;
 179
 180                c = strchr(src->line, '\n');
 181                if (c)
 182                        *c = 0;
 183
 184                src->next = NULL;
 185                *syme->lines_tail = src;
 186                syme->lines_tail = &src->next;
 187
 188                if (strlen(src->line)>8 && src->line[8] == ':') {
 189                        src->eip = strtoull(src->line, NULL, 16);
 190                        if (section)
 191                                src->eip += section->vma;
 192                }
 193                if (strlen(src->line)>8 && src->line[16] == ':') {
 194                        src->eip = strtoull(src->line, NULL, 16);
 195                        if (section)
 196                                src->eip += section->vma;
 197                }
 198        }
 199        pclose(file);
 200out_assign:
 201        sym_filter_entry = syme;
 202        pthread_mutex_unlock(&syme->source_lock);
 203}
 204
 205static void __zero_source_counters(struct sym_entry *syme)
 206{
 207        int i;
 208        struct source_line *line;
 209
 210        line = syme->lines;
 211        while (line) {
 212                for (i = 0; i < nr_counters; i++)
 213                        line->count[i] = 0;
 214                line = line->next;
 215        }
 216}
 217
 218static void record_precise_ip(struct sym_entry *syme, int counter, u64 ip)
 219{
 220        struct source_line *line;
 221
 222        if (syme != sym_filter_entry)
 223                return;
 224
 225        if (pthread_mutex_trylock(&syme->source_lock))
 226                return;
 227
 228        if (!syme->source)
 229                goto out_unlock;
 230
 231        for (line = syme->lines; line; line = line->next) {
 232                if (line->eip == ip) {
 233                        line->count[counter]++;
 234                        break;
 235                }
 236                if (line->eip > ip)
 237                        break;
 238        }
 239out_unlock:
 240        pthread_mutex_unlock(&syme->source_lock);
 241}
 242
 243static void lookup_sym_source(struct sym_entry *syme)
 244{
 245        struct symbol *symbol = (struct symbol *)(syme + 1);
 246        struct source_line *line;
 247        char pattern[PATH_MAX];
 248        char *idx;
 249
 250        sprintf(pattern, "<%s>:", symbol->name);
 251
 252        if (symbol->module) {
 253                idx = strstr(pattern, "\t");
 254                if (idx)
 255                        *idx = 0;
 256        }
 257
 258        pthread_mutex_lock(&syme->source_lock);
 259        for (line = syme->lines; line; line = line->next) {
 260                if (strstr(line->line, pattern)) {
 261                        syme->source = line;
 262                        break;
 263                }
 264        }
 265        pthread_mutex_unlock(&syme->source_lock);
 266}
 267
 268static void show_lines(struct source_line *queue, int count, int total)
 269{
 270        int i;
 271        struct source_line *line;
 272
 273        line = queue;
 274        for (i = 0; i < count; i++) {
 275                float pcnt = 100.0*(float)line->count[sym_counter]/(float)total;
 276
 277                printf("%8li %4.1f%%\t%s\n", line->count[sym_counter], pcnt, line->line);
 278                line = line->next;
 279        }
 280}
 281
 282#define TRACE_COUNT     3
 283
 284static void show_details(struct sym_entry *syme)
 285{
 286        struct symbol *symbol;
 287        struct source_line *line;
 288        struct source_line *line_queue = NULL;
 289        int displayed = 0;
 290        int line_queue_count = 0, total = 0, more = 0;
 291
 292        if (!syme)
 293                return;
 294
 295        if (!syme->source)
 296                lookup_sym_source(syme);
 297
 298        if (!syme->source)
 299                return;
 300
 301        symbol = (struct symbol *)(syme + 1);
 302        printf("Showing %s for %s\n", event_name(sym_counter), symbol->name);
 303        printf("  Events  Pcnt (>=%d%%)\n", sym_pcnt_filter);
 304
 305        pthread_mutex_lock(&syme->source_lock);
 306        line = syme->source;
 307        while (line) {
 308                total += line->count[sym_counter];
 309                line = line->next;
 310        }
 311
 312        line = syme->source;
 313        while (line) {
 314                float pcnt = 0.0;
 315
 316                if (!line_queue_count)
 317                        line_queue = line;
 318                line_queue_count++;
 319
 320                if (line->count[sym_counter])
 321                        pcnt = 100.0 * line->count[sym_counter] / (float)total;
 322                if (pcnt >= (float)sym_pcnt_filter) {
 323                        if (displayed <= print_entries)
 324                                show_lines(line_queue, line_queue_count, total);
 325                        else more++;
 326                        displayed += line_queue_count;
 327                        line_queue_count = 0;
 328                        line_queue = NULL;
 329                } else if (line_queue_count > TRACE_COUNT) {
 330                        line_queue = line_queue->next;
 331                        line_queue_count--;
 332                }
 333
 334                line->count[sym_counter] = zero ? 0 : line->count[sym_counter] * 7 / 8;
 335                line = line->next;
 336        }
 337        pthread_mutex_unlock(&syme->source_lock);
 338        if (more)
 339                printf("%d lines not displayed, maybe increase display entries [e]\n", more);
 340}
 341
 342/*
 343 * Symbols will be added here in record_ip and will get out
 344 * after decayed.
 345 */
 346static LIST_HEAD(active_symbols);
 347static pthread_mutex_t active_symbols_lock = PTHREAD_MUTEX_INITIALIZER;
 348
 349/*
 350 * Ordering weight: count-1 * count-2 * ... / count-n
 351 */
 352static double sym_weight(const struct sym_entry *sym)
 353{
 354        double weight = sym->snap_count;
 355        int counter;
 356
 357        if (!display_weighted)
 358                return weight;
 359
 360        for (counter = 1; counter < nr_counters-1; counter++)
 361                weight *= sym->count[counter];
 362
 363        weight /= (sym->count[counter] + 1);
 364
 365        return weight;
 366}
 367
 368static long                     samples;
 369static long                     userspace_samples;
 370static const char               CONSOLE_CLEAR[] = "";
 371
 372static void __list_insert_active_sym(struct sym_entry *syme)
 373{
 374        list_add(&syme->node, &active_symbols);
 375}
 376
 377static void list_remove_active_sym(struct sym_entry *syme)
 378{
 379        pthread_mutex_lock(&active_symbols_lock);
 380        list_del_init(&syme->node);
 381        pthread_mutex_unlock(&active_symbols_lock);
 382}
 383
 384static void rb_insert_active_sym(struct rb_root *tree, struct sym_entry *se)
 385{
 386        struct rb_node **p = &tree->rb_node;
 387        struct rb_node *parent = NULL;
 388        struct sym_entry *iter;
 389
 390        while (*p != NULL) {
 391                parent = *p;
 392                iter = rb_entry(parent, struct sym_entry, rb_node);
 393
 394                if (se->weight > iter->weight)
 395                        p = &(*p)->rb_left;
 396                else
 397                        p = &(*p)->rb_right;
 398        }
 399
 400        rb_link_node(&se->rb_node, parent, p);
 401        rb_insert_color(&se->rb_node, tree);
 402}
 403
 404static void print_sym_table(void)
 405{
 406        int printed = 0, j;
 407        int counter, snap = !display_weighted ? sym_counter : 0;
 408        float samples_per_sec = samples/delay_secs;
 409        float ksamples_per_sec = (samples-userspace_samples)/delay_secs;
 410        float sum_ksamples = 0.0;
 411        struct sym_entry *syme, *n;
 412        struct rb_root tmp = RB_ROOT;
 413        struct rb_node *nd;
 414
 415        samples = userspace_samples = 0;
 416
 417        /* Sort the active symbols */
 418        pthread_mutex_lock(&active_symbols_lock);
 419        syme = list_entry(active_symbols.next, struct sym_entry, node);
 420        pthread_mutex_unlock(&active_symbols_lock);
 421
 422        list_for_each_entry_safe_from(syme, n, &active_symbols, node) {
 423                syme->snap_count = syme->count[snap];
 424                if (syme->snap_count != 0) {
 425                        syme->weight = sym_weight(syme);
 426                        rb_insert_active_sym(&tmp, syme);
 427                        sum_ksamples += syme->snap_count;
 428
 429                        for (j = 0; j < nr_counters; j++)
 430                                syme->count[j] = zero ? 0 : syme->count[j] * 7 / 8;
 431                } else
 432                        list_remove_active_sym(syme);
 433        }
 434
 435        puts(CONSOLE_CLEAR);
 436
 437        printf(
 438"------------------------------------------------------------------------------\n");
 439        printf( "   PerfTop:%8.0f irqs/sec  kernel:%4.1f%% [",
 440                samples_per_sec,
 441                100.0 - (100.0*((samples_per_sec-ksamples_per_sec)/samples_per_sec)));
 442
 443        if (nr_counters == 1 || !display_weighted) {
 444                printf("%Ld", (u64)attrs[0].sample_period);
 445                if (freq)
 446                        printf("Hz ");
 447                else
 448                        printf(" ");
 449        }
 450
 451        if (!display_weighted)
 452                printf("%s", event_name(sym_counter));
 453        else for (counter = 0; counter < nr_counters; counter++) {
 454                if (counter)
 455                        printf("/");
 456
 457                printf("%s", event_name(counter));
 458        }
 459
 460        printf( "], ");
 461
 462        if (target_pid != -1)
 463                printf(" (target_pid: %d", target_pid);
 464        else
 465                printf(" (all");
 466
 467        if (profile_cpu != -1)
 468                printf(", cpu: %d)\n", profile_cpu);
 469        else {
 470                if (target_pid != -1)
 471                        printf(")\n");
 472                else
 473                        printf(", %d CPUs)\n", nr_cpus);
 474        }
 475
 476        printf("------------------------------------------------------------------------------\n\n");
 477
 478        if (sym_filter_entry) {
 479                show_details(sym_filter_entry);
 480                return;
 481        }
 482
 483        if (nr_counters == 1)
 484                printf("             samples    pcnt");
 485        else
 486                printf("   weight    samples    pcnt");
 487
 488        if (verbose)
 489                printf("         RIP       ");
 490        printf("   kernel function\n");
 491        printf("   %s    _______   _____",
 492               nr_counters == 1 ? "      " : "______");
 493        if (verbose)
 494                printf("   ________________");
 495        printf("   _______________\n\n");
 496
 497        for (nd = rb_first(&tmp); nd; nd = rb_next(nd)) {
 498                struct symbol *sym;
 499                double pcnt;
 500
 501                syme = rb_entry(nd, struct sym_entry, rb_node);
 502                sym = (struct symbol *)(syme + 1);
 503
 504                if (++printed > print_entries || (int)syme->snap_count < count_filter)
 505                        continue;
 506
 507                pcnt = 100.0 - (100.0 * ((sum_ksamples - syme->snap_count) /
 508                                         sum_ksamples));
 509
 510                if (nr_counters == 1 || !display_weighted)
 511                        printf("%20.2f - ", syme->weight);
 512                else
 513                        printf("%9.1f %10ld - ", syme->weight, syme->snap_count);
 514
 515                percent_color_fprintf(stdout, "%4.1f%%", pcnt);
 516                if (verbose)
 517                        printf(" - %016llx", sym->start);
 518                printf(" : %s", sym->name);
 519                if (sym->module)
 520                        printf("\t[%s]", sym->module->name);
 521                printf("\n");
 522        }
 523}
 524
 525static void prompt_integer(int *target, const char *msg)
 526{
 527        char *buf = malloc(0), *p;
 528        size_t dummy = 0;
 529        int tmp;
 530
 531        fprintf(stdout, "\n%s: ", msg);
 532        if (getline(&buf, &dummy, stdin) < 0)
 533                return;
 534
 535        p = strchr(buf, '\n');
 536        if (p)
 537                *p = 0;
 538
 539        p = buf;
 540        while(*p) {
 541                if (!isdigit(*p))
 542                        goto out_free;
 543                p++;
 544        }
 545        tmp = strtoul(buf, NULL, 10);
 546        *target = tmp;
 547out_free:
 548        free(buf);
 549}
 550
 551static void prompt_percent(int *target, const char *msg)
 552{
 553        int tmp = 0;
 554
 555        prompt_integer(&tmp, msg);
 556        if (tmp >= 0 && tmp <= 100)
 557                *target = tmp;
 558}
 559
 560static void prompt_symbol(struct sym_entry **target, const char *msg)
 561{
 562        char *buf = malloc(0), *p;
 563        struct sym_entry *syme = *target, *n, *found = NULL;
 564        size_t dummy = 0;
 565
 566        /* zero counters of active symbol */
 567        if (syme) {
 568                pthread_mutex_lock(&syme->source_lock);
 569                __zero_source_counters(syme);
 570                *target = NULL;
 571                pthread_mutex_unlock(&syme->source_lock);
 572        }
 573
 574        fprintf(stdout, "\n%s: ", msg);
 575        if (getline(&buf, &dummy, stdin) < 0)
 576                goto out_free;
 577
 578        p = strchr(buf, '\n');
 579        if (p)
 580                *p = 0;
 581
 582        pthread_mutex_lock(&active_symbols_lock);
 583        syme = list_entry(active_symbols.next, struct sym_entry, node);
 584        pthread_mutex_unlock(&active_symbols_lock);
 585
 586        list_for_each_entry_safe_from(syme, n, &active_symbols, node) {
 587                struct symbol *sym = (struct symbol *)(syme + 1);
 588
 589                if (!strcmp(buf, sym->name)) {
 590                        found = syme;
 591                        break;
 592                }
 593        }
 594
 595        if (!found) {
 596                fprintf(stderr, "Sorry, %s is not active.\n", sym_filter);
 597                sleep(1);
 598                return;
 599        } else
 600                parse_source(found);
 601
 602out_free:
 603        free(buf);
 604}
 605
 606static void print_mapped_keys(void)
 607{
 608        char *name = NULL;
 609
 610        if (sym_filter_entry) {
 611                struct symbol *sym = (struct symbol *)(sym_filter_entry+1);
 612                name = sym->name;
 613        }
 614
 615        fprintf(stdout, "\nMapped keys:\n");
 616        fprintf(stdout, "\t[d]     display refresh delay.             \t(%d)\n", delay_secs);
 617        fprintf(stdout, "\t[e]     display entries (lines).           \t(%d)\n", print_entries);
 618
 619        if (nr_counters > 1)
 620                fprintf(stdout, "\t[E]     active event counter.              \t(%s)\n", event_name(sym_counter));
 621
 622        fprintf(stdout, "\t[f]     profile display filter (count).    \t(%d)\n", count_filter);
 623
 624        if (vmlinux_name) {
 625                fprintf(stdout, "\t[F]     annotate display filter (percent). \t(%d%%)\n", sym_pcnt_filter);
 626                fprintf(stdout, "\t[s]     annotate symbol.                   \t(%s)\n", name?: "NULL");
 627                fprintf(stdout, "\t[S]     stop annotation.\n");
 628        }
 629
 630        if (nr_counters > 1)
 631                fprintf(stdout, "\t[w]     toggle display weighted/count[E]r. \t(%d)\n", display_weighted ? 1 : 0);
 632
 633        fprintf(stdout, "\t[z]     toggle sample zeroing.             \t(%d)\n", zero ? 1 : 0);
 634        fprintf(stdout, "\t[qQ]    quit.\n");
 635}
 636
 637static int key_mapped(int c)
 638{
 639        switch (c) {
 640                case 'd':
 641                case 'e':
 642                case 'f':
 643                case 'z':
 644                case 'q':
 645                case 'Q':
 646                        return 1;
 647                case 'E':
 648                case 'w':
 649                        return nr_counters > 1 ? 1 : 0;
 650                case 'F':
 651                case 's':
 652                case 'S':
 653                        return vmlinux_name ? 1 : 0;
 654                default:
 655                        break;
 656        }
 657
 658        return 0;
 659}
 660
 661static void handle_keypress(int c)
 662{
 663        if (!key_mapped(c)) {
 664                struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };
 665                struct termios tc, save;
 666
 667                print_mapped_keys();
 668                fprintf(stdout, "\nEnter selection, or unmapped key to continue: ");
 669                fflush(stdout);
 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                if (!key_mapped(c))
 683                        return;
 684        }
 685
 686        switch (c) {
 687                case 'd':
 688                        prompt_integer(&delay_secs, "Enter display delay");
 689                        if (delay_secs < 1)
 690                                delay_secs = 1;
 691                        break;
 692                case 'e':
 693                        prompt_integer(&print_entries, "Enter display entries (lines)");
 694                        break;
 695                case 'E':
 696                        if (nr_counters > 1) {
 697                                int i;
 698
 699                                fprintf(stderr, "\nAvailable events:");
 700                                for (i = 0; i < nr_counters; i++)
 701                                        fprintf(stderr, "\n\t%d %s", i, event_name(i));
 702
 703                                prompt_integer(&sym_counter, "Enter details event counter");
 704
 705                                if (sym_counter >= nr_counters) {
 706                                        fprintf(stderr, "Sorry, no such event, using %s.\n", event_name(0));
 707                                        sym_counter = 0;
 708                                        sleep(1);
 709                                }
 710                        } else sym_counter = 0;
 711                        break;
 712                case 'f':
 713                        prompt_integer(&count_filter, "Enter display event count filter");
 714                        break;
 715                case 'F':
 716                        prompt_percent(&sym_pcnt_filter, "Enter details display event filter (percent)");
 717                        break;
 718                case 'q':
 719                case 'Q':
 720                        printf("exiting.\n");
 721                        exit(0);
 722                case 's':
 723                        prompt_symbol(&sym_filter_entry, "Enter details symbol");
 724                        break;
 725                case 'S':
 726                        if (!sym_filter_entry)
 727                                break;
 728                        else {
 729                                struct sym_entry *syme = sym_filter_entry;
 730
 731                                pthread_mutex_lock(&syme->source_lock);
 732                                sym_filter_entry = NULL;
 733                                __zero_source_counters(syme);
 734                                pthread_mutex_unlock(&syme->source_lock);
 735                        }
 736                        break;
 737                case 'w':
 738                        display_weighted = ~display_weighted;
 739                        break;
 740                case 'z':
 741                        zero = ~zero;
 742                        break;
 743                default:
 744                        break;
 745        }
 746}
 747
 748static void *display_thread(void *arg __used)
 749{
 750        struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };
 751        struct termios tc, save;
 752        int delay_msecs, c;
 753
 754        tcgetattr(0, &save);
 755        tc = save;
 756        tc.c_lflag &= ~(ICANON | ECHO);
 757        tc.c_cc[VMIN] = 0;
 758        tc.c_cc[VTIME] = 0;
 759
 760repeat:
 761        delay_msecs = delay_secs * 1000;
 762        tcsetattr(0, TCSANOW, &tc);
 763        /* trash return*/
 764        getc(stdin);
 765
 766        do {
 767                print_sym_table();
 768        } while (!poll(&stdin_poll, 1, delay_msecs) == 1);
 769
 770        c = getc(stdin);
 771        tcsetattr(0, TCSAFLUSH, &save);
 772
 773        handle_keypress(c);
 774        goto repeat;
 775
 776        return NULL;
 777}
 778
 779/* Tag samples to be skipped. */
 780static const char *skip_symbols[] = {
 781        "default_idle",
 782        "cpu_idle",
 783        "enter_idle",
 784        "exit_idle",
 785        "mwait_idle",
 786        "mwait_idle_with_hints",
 787        "poll_idle",
 788        "ppc64_runlatch_off",
 789        "pseries_dedicated_idle_sleep",
 790        NULL
 791};
 792
 793static int symbol_filter(struct dso *self, struct symbol *sym)
 794{
 795        struct sym_entry *syme;
 796        const char *name = sym->name;
 797        int i;
 798
 799        /*
 800         * ppc64 uses function descriptors and appends a '.' to the
 801         * start of every instruction address. Remove it.
 802         */
 803        if (name[0] == '.')
 804                name++;
 805
 806        if (!strcmp(name, "_text") ||
 807            !strcmp(name, "_etext") ||
 808            !strcmp(name, "_sinittext") ||
 809            !strncmp("init_module", name, 11) ||
 810            !strncmp("cleanup_module", name, 14) ||
 811            strstr(name, "_text_start") ||
 812            strstr(name, "_text_end"))
 813                return 1;
 814
 815        syme = dso__sym_priv(self, sym);
 816        pthread_mutex_init(&syme->source_lock, NULL);
 817        if (!sym_filter_entry && sym_filter && !strcmp(name, sym_filter))
 818                sym_filter_entry = syme;
 819
 820        for (i = 0; skip_symbols[i]; i++) {
 821                if (!strcmp(skip_symbols[i], name)) {
 822                        syme->skip = 1;
 823                        break;
 824                }
 825        }
 826
 827        return 0;
 828}
 829
 830static int parse_symbols(void)
 831{
 832        struct rb_node *node;
 833        struct symbol  *sym;
 834        int use_modules = vmlinux_name ? 1 : 0;
 835
 836        kernel_dso = dso__new("[kernel]", sizeof(struct sym_entry));
 837        if (kernel_dso == NULL)
 838                return -1;
 839
 840        if (dso__load_kernel(kernel_dso, vmlinux_name, symbol_filter, verbose, use_modules) <= 0)
 841                goto out_delete_dso;
 842
 843        node = rb_first(&kernel_dso->syms);
 844        sym = rb_entry(node, struct symbol, rb_node);
 845        min_ip = sym->start;
 846
 847        node = rb_last(&kernel_dso->syms);
 848        sym = rb_entry(node, struct symbol, rb_node);
 849        max_ip = sym->end;
 850
 851        if (dump_symtab)
 852                dso__fprintf(kernel_dso, stderr);
 853
 854        return 0;
 855
 856out_delete_dso:
 857        dso__delete(kernel_dso);
 858        kernel_dso = NULL;
 859        return -1;
 860}
 861
 862/*
 863 * Binary search in the histogram table and record the hit:
 864 */
 865static void record_ip(u64 ip, int counter)
 866{
 867        struct symbol *sym = dso__find_symbol(kernel_dso, ip);
 868
 869        if (sym != NULL) {
 870                struct sym_entry *syme = dso__sym_priv(kernel_dso, sym);
 871
 872                if (!syme->skip) {
 873                        syme->count[counter]++;
 874                        record_precise_ip(syme, counter, ip);
 875                        pthread_mutex_lock(&active_symbols_lock);
 876                        if (list_empty(&syme->node) || !syme->node.next)
 877                                __list_insert_active_sym(syme);
 878                        pthread_mutex_unlock(&active_symbols_lock);
 879                        return;
 880                }
 881        }
 882
 883        samples--;
 884}
 885
 886static void process_event(u64 ip, int counter, int user)
 887{
 888        samples++;
 889
 890        if (user) {
 891                userspace_samples++;
 892                return;
 893        }
 894
 895        record_ip(ip, counter);
 896}
 897
 898struct mmap_data {
 899        int                     counter;
 900        void                    *base;
 901        int                     mask;
 902        unsigned int            prev;
 903};
 904
 905static unsigned int mmap_read_head(struct mmap_data *md)
 906{
 907        struct perf_event_mmap_page *pc = md->base;
 908        int head;
 909
 910        head = pc->data_head;
 911        rmb();
 912
 913        return head;
 914}
 915
 916struct timeval last_read, this_read;
 917
 918static void mmap_read_counter(struct mmap_data *md)
 919{
 920        unsigned int head = mmap_read_head(md);
 921        unsigned int old = md->prev;
 922        unsigned char *data = md->base + page_size;
 923        int diff;
 924
 925        gettimeofday(&this_read, NULL);
 926
 927        /*
 928         * If we're further behind than half the buffer, there's a chance
 929         * the writer will bite our tail and mess up the samples under us.
 930         *
 931         * If we somehow ended up ahead of the head, we got messed up.
 932         *
 933         * In either case, truncate and restart at head.
 934         */
 935        diff = head - old;
 936        if (diff > md->mask / 2 || diff < 0) {
 937                struct timeval iv;
 938                unsigned long msecs;
 939
 940                timersub(&this_read, &last_read, &iv);
 941                msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
 942
 943                fprintf(stderr, "WARNING: failed to keep up with mmap data."
 944                                "  Last read %lu msecs ago.\n", msecs);
 945
 946                /*
 947                 * head points to a known good entry, start there.
 948                 */
 949                old = head;
 950        }
 951
 952        last_read = this_read;
 953
 954        for (; old != head;) {
 955                event_t *event = (event_t *)&data[old & md->mask];
 956
 957                event_t event_copy;
 958
 959                size_t size = event->header.size;
 960
 961                /*
 962                 * Event straddles the mmap boundary -- header should always
 963                 * be inside due to u64 alignment of output.
 964                 */
 965                if ((old & md->mask) + size != ((old + size) & md->mask)) {
 966                        unsigned int offset = old;
 967                        unsigned int len = min(sizeof(*event), size), cpy;
 968                        void *dst = &event_copy;
 969
 970                        do {
 971                                cpy = min(md->mask + 1 - (offset & md->mask), len);
 972                                memcpy(dst, &data[offset & md->mask], cpy);
 973                                offset += cpy;
 974                                dst += cpy;
 975                                len -= cpy;
 976                        } while (len);
 977
 978                        event = &event_copy;
 979                }
 980
 981                old += size;
 982
 983                if (event->header.type == PERF_RECORD_SAMPLE) {
 984                        int user =
 985        (event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK) == PERF_RECORD_MISC_USER;
 986                        process_event(event->ip.ip, md->counter, user);
 987                }
 988        }
 989
 990        md->prev = old;
 991}
 992
 993static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
 994static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
 995
 996static void mmap_read(void)
 997{
 998        int i, counter;
 999
1000        for (i = 0; i < nr_cpus; i++) {
1001                for (counter = 0; counter < nr_counters; counter++)
1002                        mmap_read_counter(&mmap_array[i][counter]);
1003        }
1004}
1005
1006int nr_poll;
1007int group_fd;
1008
1009static void start_counter(int i, int counter)
1010{
1011        struct perf_event_attr *attr;
1012        int cpu;
1013
1014        cpu = profile_cpu;
1015        if (target_pid == -1 && profile_cpu == -1)
1016                cpu = i;
1017
1018        attr = attrs + counter;
1019
1020        attr->sample_type       = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
1021        attr->freq              = freq;
1022        attr->inherit           = (cpu < 0) && inherit;
1023
1024try_again:
1025        fd[i][counter] = sys_perf_event_open(attr, target_pid, cpu, group_fd, 0);
1026
1027        if (fd[i][counter] < 0) {
1028                int err = errno;
1029
1030                if (err == EPERM || err == EACCES)
1031                        die("No permission - are you root?\n");
1032                /*
1033                 * If it's cycles then fall back to hrtimer
1034                 * based cpu-clock-tick sw counter, which
1035                 * is always available even if no PMU support:
1036                 */
1037                if (attr->type == PERF_TYPE_HARDWARE
1038                        && attr->config == PERF_COUNT_HW_CPU_CYCLES) {
1039
1040                        if (verbose)
1041                                warning(" ... trying to fall back to cpu-clock-ticks\n");
1042
1043                        attr->type = PERF_TYPE_SOFTWARE;
1044                        attr->config = PERF_COUNT_SW_CPU_CLOCK;
1045                        goto try_again;
1046                }
1047                printf("\n");
1048                error("perfcounter syscall returned with %d (%s)\n",
1049                        fd[i][counter], strerror(err));
1050                die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
1051                exit(-1);
1052        }
1053        assert(fd[i][counter] >= 0);
1054        fcntl(fd[i][counter], F_SETFL, O_NONBLOCK);
1055
1056        /*
1057         * First counter acts as the group leader:
1058         */
1059        if (group && group_fd == -1)
1060                group_fd = fd[i][counter];
1061
1062        event_array[nr_poll].fd = fd[i][counter];
1063        event_array[nr_poll].events = POLLIN;
1064        nr_poll++;
1065
1066        mmap_array[i][counter].counter = counter;
1067        mmap_array[i][counter].prev = 0;
1068        mmap_array[i][counter].mask = mmap_pages*page_size - 1;
1069        mmap_array[i][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
1070                        PROT_READ, MAP_SHARED, fd[i][counter], 0);
1071        if (mmap_array[i][counter].base == MAP_FAILED)
1072                die("failed to mmap with %d (%s)\n", errno, strerror(errno));
1073}
1074
1075static int __cmd_top(void)
1076{
1077        pthread_t thread;
1078        int i, counter;
1079        int ret;
1080
1081        for (i = 0; i < nr_cpus; i++) {
1082                group_fd = -1;
1083                for (counter = 0; counter < nr_counters; counter++)
1084                        start_counter(i, counter);
1085        }
1086
1087        /* Wait for a minimal set of events before starting the snapshot */
1088        poll(event_array, nr_poll, 100);
1089
1090        mmap_read();
1091
1092        if (pthread_create(&thread, NULL, display_thread, NULL)) {
1093                printf("Could not create display thread.\n");
1094                exit(-1);
1095        }
1096
1097        if (realtime_prio) {
1098                struct sched_param param;
1099
1100                param.sched_priority = realtime_prio;
1101                if (sched_setscheduler(0, SCHED_FIFO, &param)) {
1102                        printf("Could not set realtime priority.\n");
1103                        exit(-1);
1104                }
1105        }
1106
1107        while (1) {
1108                int hits = samples;
1109
1110                mmap_read();
1111
1112                if (hits == samples)
1113                        ret = poll(event_array, nr_poll, 100);
1114        }
1115
1116        return 0;
1117}
1118
1119static const char * const top_usage[] = {
1120        "perf top [<options>]",
1121        NULL
1122};
1123
1124static const struct option options[] = {
1125        OPT_CALLBACK('e', "event", NULL, "event",
1126                     "event selector. use 'perf list' to list available events",
1127                     parse_events),
1128        OPT_INTEGER('c', "count", &default_interval,
1129                    "event period to sample"),
1130        OPT_INTEGER('p', "pid", &target_pid,
1131                    "profile events on existing pid"),
1132        OPT_BOOLEAN('a', "all-cpus", &system_wide,
1133                            "system-wide collection from all CPUs"),
1134        OPT_INTEGER('C', "CPU", &profile_cpu,
1135                    "CPU to profile on"),
1136        OPT_STRING('k', "vmlinux", &vmlinux_name, "file", "vmlinux pathname"),
1137        OPT_INTEGER('m', "mmap-pages", &mmap_pages,
1138                    "number of mmap data pages"),
1139        OPT_INTEGER('r', "realtime", &realtime_prio,
1140                    "collect data with this RT SCHED_FIFO priority"),
1141        OPT_INTEGER('d', "delay", &delay_secs,
1142                    "number of seconds to delay between refreshes"),
1143        OPT_BOOLEAN('D', "dump-symtab", &dump_symtab,
1144                            "dump the symbol table used for profiling"),
1145        OPT_INTEGER('f', "count-filter", &count_filter,
1146                    "only display functions with more events than this"),
1147        OPT_BOOLEAN('g', "group", &group,
1148                            "put the counters into a counter group"),
1149        OPT_BOOLEAN('i', "inherit", &inherit,
1150                    "child tasks inherit counters"),
1151        OPT_STRING('s', "sym-annotate", &sym_filter, "symbol name",
1152                    "symbol to annotate - requires -k option"),
1153        OPT_BOOLEAN('z', "zero", &zero,
1154                    "zero history across updates"),
1155        OPT_INTEGER('F', "freq", &freq,
1156                    "profile at this frequency"),
1157        OPT_INTEGER('E', "entries", &print_entries,
1158                    "display this many functions"),
1159        OPT_BOOLEAN('v', "verbose", &verbose,
1160                    "be more verbose (show counter open errors, etc)"),
1161        OPT_END()
1162};
1163
1164int cmd_top(int argc, const char **argv, const char *prefix __used)
1165{
1166        int counter;
1167
1168        symbol__init();
1169
1170        page_size = sysconf(_SC_PAGE_SIZE);
1171
1172        argc = parse_options(argc, argv, options, top_usage, 0);
1173        if (argc)
1174                usage_with_options(top_usage, options);
1175
1176        if (freq) {
1177                default_interval = freq;
1178                freq = 1;
1179        }
1180
1181        /* CPU and PID are mutually exclusive */
1182        if (target_pid != -1 && profile_cpu != -1) {
1183                printf("WARNING: PID switch overriding CPU\n");
1184                sleep(1);
1185                profile_cpu = -1;
1186        }
1187
1188        if (!nr_counters)
1189                nr_counters = 1;
1190
1191        if (delay_secs < 1)
1192                delay_secs = 1;
1193
1194        parse_symbols();
1195        parse_source(sym_filter_entry);
1196
1197        /*
1198         * Fill in the ones not specifically initialized via -c:
1199         */
1200        for (counter = 0; counter < nr_counters; counter++) {
1201                if (attrs[counter].sample_period)
1202                        continue;
1203
1204                attrs[counter].sample_period = default_interval;
1205        }
1206
1207        nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
1208        assert(nr_cpus <= MAX_NR_CPUS);
1209        assert(nr_cpus >= 0);
1210
1211        if (target_pid != -1 || profile_cpu != -1)
1212                nr_cpus = 1;
1213
1214        return __cmd_top();
1215}
1216
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