tools/perf/perf.c

   1 /*
   2  * perf.c
   3  *
   4  * Performance analysis utility.
   5  *
   6  * This is the main hub from which the sub-commands (perf stat,
   7  * perf top, perf record, perf report, etc.) are started.
   8  */
   9 #include "builtin.h"
  10
  11 #include "util/env.h"
  12 #include <subcmd/exec-cmd.h>
  13 #include "util/config.h"
  14 #include "util/quote.h"
  15 #include <subcmd/run-command.h>
  16 #include "util/parse-events.h"
  17 #include <subcmd/parse-options.h>
  18 #include "util/bpf-loader.h"
  19 #include "util/debug.h"
  20 #include <api/fs/fs.h>
  21 #include <api/fs/tracing_path.h>
  22 #include <pthread.h>
  23 #include <stdlib.h>
  24 #include <time.h>
  25
  26 const char perf_usage_string[] =
  27         "perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
  28
  29 const char perf_more_info_string[] =
  30         "See 'perf help COMMAND' for more information on a specific command.";
  31
  32 static int use_pager = -1;
  33 const char *input_name;
  34
  35 struct cmd_struct {
  36         const char *cmd;
  37         int (*fn)(int, const char **, const char *);
  38         int option;
  39 };
  40
  41 static struct cmd_struct commands[] = {
  42         { "buildid-cache", cmd_buildid_cache, 0 },
  43         { "buildid-list", cmd_buildid_list, 0 },
  44         { "config",     cmd_config,     0 },
  45         { "c2c",        cmd_c2c,        0 },
  46         { "diff",       cmd_diff,       0 },
  47         { "evlist",     cmd_evlist,     0 },
  48         { "help",       cmd_help,       0 },
  49         { "kallsyms",   cmd_kallsyms,   0 },
  50         { "list",       cmd_list,       0 },
  51         { "record",     cmd_record,     0 },
  52         { "report",     cmd_report,     0 },
  53         { "bench",      cmd_bench,      0 },
  54         { "stat",       cmd_stat,       0 },
  55         { "timechart",  cmd_timechart,  0 },
  56         { "top",        cmd_top,        0 },
  57         { "annotate",   cmd_annotate,   0 },
  58         { "version",    cmd_version,    0 },
  59         { "script",     cmd_script,     0 },
  60         { "sched",      cmd_sched,      0 },
  61 #ifdef HAVE_LIBELF_SUPPORT
  62         { "probe",      cmd_probe,      0 },
  63 #endif
  64         { "kmem",       cmd_kmem,       0 },
  65         { "lock",       cmd_lock,       0 },
  66         { "kvm",        cmd_kvm,        0 },
  67         { "test",       cmd_test,       0 },
  68 #ifdef HAVE_LIBAUDIT_SUPPORT
  69         { "trace",      cmd_trace,      0 },
  70 #endif
  71         { "inject",     cmd_inject,     0 },
  72         { "mem",        cmd_mem,        0 },
  73         { "data",       cmd_data,       0 },
  74 };
  75
  76 struct pager_config {
  77         const char *cmd;
  78         int val;
  79 };
  80
  81 static int pager_command_config(const char *var, const char *value, void *data)
  82 {
  83         struct pager_config *c = data;
  84         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  85                 c->val = perf_config_bool(var, value);
  86         return 0;
  87 }
  88
  89 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  90 int check_pager_config(const char *cmd)
  91 {
  92         struct pager_config c;
  93         c.cmd = cmd;
  94         c.val = -1;
  95         perf_config(pager_command_config, &c);
  96         return c.val;
  97 }
  98
  99 static int browser_command_config(const char *var, const char *value, void *data)
 100 {
 101         struct pager_config *c = data;
 102         if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
 103                 c->val = perf_config_bool(var, value);
 104         if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
 105                 c->val = perf_config_bool(var, value) ? 2 : 0;
 106         return 0;
 107 }
 108
 109 /*
 110  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
 111  * and -1 for "not specified"
 112  */
 113 static int check_browser_config(const char *cmd)
 114 {
 115         struct pager_config c;
 116         c.cmd = cmd;
 117         c.val = -1;
 118         perf_config(browser_command_config, &c);
 119         return c.val;
 120 }
 121
 122 static void commit_pager_choice(void)
 123 {
 124         switch (use_pager) {
 125         case 0:
 126                 setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
 127                 break;
 128         case 1:
 129                 /* setup_pager(); */
 130                 break;
 131         default:
 132                 break;
 133         }
 134 }
 135
 136 struct option options[] = {
 137         OPT_ARGUMENT("help", "help"),
 138         OPT_ARGUMENT("version", "version"),
 139         OPT_ARGUMENT("exec-path", "exec-path"),
 140         OPT_ARGUMENT("html-path", "html-path"),
 141         OPT_ARGUMENT("paginate", "paginate"),
 142         OPT_ARGUMENT("no-pager", "no-pager"),
 143         OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
 144         OPT_ARGUMENT("buildid-dir", "buildid-dir"),
 145         OPT_ARGUMENT("list-cmds", "list-cmds"),
 146         OPT_ARGUMENT("list-opts", "list-opts"),
 147         OPT_ARGUMENT("debug", "debug"),
 148         OPT_END()
 149 };
 150
 151 static int handle_options(const char ***argv, int *argc, int *envchanged)
 152 {
 153         int handled = 0;
 154
 155         while (*argc > 0) {
 156                 const char *cmd = (*argv)[0];
 157                 if (cmd[0] != '-')
 158                         break;
 159
 160                 /*
 161                  * For legacy reasons, the "version" and "help"
 162                  * commands can be written with "--" prepended
 163                  * to make them look like flags.
 164                  */
 165                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 166                         break;
 167
 168                 /*
 169                  * Shortcut for '-h' and '-v' options to invoke help
 170                  * and version command.
 171                  */
 172                 if (!strcmp(cmd, "-h")) {
 173                         (*argv)[0] = "--help";
 174                         break;
 175                 }
 176
 177                 if (!strcmp(cmd, "-v")) {
 178                         (*argv)[0] = "--version";
 179                         break;
 180                 }
 181
 182                 /*
 183                  * Check remaining flags.
 184                  */
 185                 if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
 186                         cmd += strlen(CMD_EXEC_PATH);
 187                         if (*cmd == '=')
 188                                 set_argv_exec_path(cmd + 1);
 189                         else {
 190                                 puts(get_argv_exec_path());
 191                                 exit(0);
 192                         }
 193                 } else if (!strcmp(cmd, "--html-path")) {
 194                         puts(system_path(PERF_HTML_PATH));
 195                         exit(0);
 196                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 197                         use_pager = 1;
 198                 } else if (!strcmp(cmd, "--no-pager")) {
 199                         use_pager = 0;
 200                         if (envchanged)
 201                                 *envchanged = 1;
 202                 } else if (!strcmp(cmd, "--debugfs-dir")) {
 203                         if (*argc < 2) {
 204                                 fprintf(stderr, "No directory given for --debugfs-dir.\n");
 205                                 usage(perf_usage_string);
 206                         }
 207                         tracing_path_set((*argv)[1]);
 208                         if (envchanged)
 209                                 *envchanged = 1;
 210                         (*argv)++;
 211                         (*argc)--;
 212                 } else if (!strcmp(cmd, "--buildid-dir")) {
 213                         if (*argc < 2) {
 214                                 fprintf(stderr, "No directory given for --buildid-dir.\n");
 215                                 usage(perf_usage_string);
 216                         }
 217                         set_buildid_dir((*argv)[1]);
 218                         if (envchanged)
 219                                 *envchanged = 1;
 220                         (*argv)++;
 221                         (*argc)--;
 222                 } else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
 223                         tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
 224                         fprintf(stderr, "dir: %s\n", tracing_path);
 225                         if (envchanged)
 226                                 *envchanged = 1;
 227                 } else if (!strcmp(cmd, "--list-cmds")) {
 228                         unsigned int i;
 229
 230                         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 231                                 struct cmd_struct *p = commands+i;
 232                                 printf("%s ", p->cmd);
 233                         }
 234                         putchar('\n');
 235                         exit(0);
 236                 } else if (!strcmp(cmd, "--list-opts")) {
 237                         unsigned int i;
 238
 239                         for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
 240                                 struct option *p = options+i;
 241                                 printf("--%s ", p->long_name);
 242                         }
 243                         putchar('\n');
 244                         exit(0);
 245                 } else if (!strcmp(cmd, "--debug")) {
 246                         if (*argc < 2) {
 247                                 fprintf(stderr, "No variable specified for --debug.\n");
 248                                 usage(perf_usage_string);
 249                         }
 250                         if (perf_debug_option((*argv)[1]))
 251                                 usage(perf_usage_string);
 252
 253                         (*argv)++;
 254                         (*argc)--;
 255                 } else {
 256                         fprintf(stderr, "Unknown option: %s\n", cmd);
 257                         usage(perf_usage_string);
 258                 }
 259
 260                 (*argv)++;
 261                 (*argc)--;
 262                 handled++;
 263         }
 264         return handled;
 265 }
 266
 267 static int handle_alias(int *argcp, const char ***argv)
 268 {
 269         int envchanged = 0, ret = 0, saved_errno = errno;
 270         int count, option_count;
 271         const char **new_argv;
 272         const char *alias_command;
 273         char *alias_string;
 274
 275         alias_command = (*argv)[0];
 276         alias_string = alias_lookup(alias_command);
 277         if (alias_string) {
 278                 if (alias_string[0] == '!') {
 279                         if (*argcp > 1) {
 280                                 struct strbuf buf;
 281
 282                                 if (strbuf_init(&buf, PATH_MAX) < 0 ||
 283                                     strbuf_addstr(&buf, alias_string) < 0 ||
 284                                     sq_quote_argv(&buf, (*argv) + 1,
 285                                                   PATH_MAX) < 0)
 286                                         die("Failed to allocate memory.");
 287                                 free(alias_string);
 288                                 alias_string = buf.buf;
 289                         }
 290                         ret = system(alias_string + 1);
 291                         if (ret >= 0 && WIFEXITED(ret) &&
 292                             WEXITSTATUS(ret) != 127)
 293                                 exit(WEXITSTATUS(ret));
 294                         die("Failed to run '%s' when expanding alias '%s'",
 295                             alias_string + 1, alias_command);
 296                 }
 297                 count = split_cmdline(alias_string, &new_argv);
 298                 if (count < 0)
 299                         die("Bad alias.%s string", alias_command);
 300                 option_count = handle_options(&new_argv, &count, &envchanged);
 301                 if (envchanged)
 302                         die("alias '%s' changes environment variables\n"
 303                                  "You can use '!perf' in the alias to do this.",
 304                                  alias_command);
 305                 memmove(new_argv - option_count, new_argv,
 306                                 count * sizeof(char *));
 307                 new_argv -= option_count;
 308
 309                 if (count < 1)
 310                         die("empty alias for %s", alias_command);
 311
 312                 if (!strcmp(alias_command, new_argv[0]))
 313                         die("recursive alias: %s", alias_command);
 314
 315                 new_argv = realloc(new_argv, sizeof(char *) *
 316                                     (count + *argcp + 1));
 317                 /* insert after command name */
 318                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 319                 new_argv[count + *argcp] = NULL;
 320
 321                 *argv = new_argv;
 322                 *argcp += count - 1;
 323
 324                 ret = 1;
 325         }
 326
 327         errno = saved_errno;
 328
 329         return ret;
 330 }
 331
 332 #define RUN_SETUP       (1<<0)
 333 #define USE_PAGER       (1<<1)
 334
 335 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 336 {
 337         int status;
 338         struct stat st;
 339         const char *prefix;
 340         char sbuf[STRERR_BUFSIZE];
 341
 342         prefix = NULL;
 343         if (p->option & RUN_SETUP)
 344                 prefix = NULL; /* setup_perf_directory(); */
 345
 346         if (use_browser == -1)
 347                 use_browser = check_browser_config(p->cmd);
 348
 349         if (use_pager == -1 && p->option & RUN_SETUP)
 350                 use_pager = check_pager_config(p->cmd);
 351         if (use_pager == -1 && p->option & USE_PAGER)
 352                 use_pager = 1;
 353         commit_pager_choice();
 354
 355         perf_env__set_cmdline(&perf_env, argc, argv);
 356         status = p->fn(argc, argv, prefix);
 357         perf_config__exit();
 358         exit_browser(status);
 359         perf_env__exit(&perf_env);
 360         bpf__clear();
 361
 362         if (status)
 363                 return status & 0xff;
 364
 365         /* Somebody closed stdout? */
 366         if (fstat(fileno(stdout), &st))
 367                 return 0;
 368         /* Ignore write errors for pipes and sockets.. */
 369         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 370                 return 0;
 371
 372         status = 1;
 373         /* Check for ENOSPC and EIO errors.. */
 374         if (fflush(stdout)) {
 375                 fprintf(stderr, "write failure on standard output: %s",
 376                         str_error_r(errno, sbuf, sizeof(sbuf)));
 377                 goto out;
 378         }
 379         if (ferror(stdout)) {
 380                 fprintf(stderr, "unknown write failure on standard output");
 381                 goto out;
 382         }
 383         if (fclose(stdout)) {
 384                 fprintf(stderr, "close failed on standard output: %s",
 385                         str_error_r(errno, sbuf, sizeof(sbuf)));
 386                 goto out;
 387         }
 388         status = 0;
 389 out:
 390         return status;
 391 }
 392
 393 static void handle_internal_command(int argc, const char **argv)
 394 {
 395         const char *cmd = argv[0];
 396         unsigned int i;
 397         static const char ext[] = STRIP_EXTENSION;
 398
 399         if (sizeof(ext) > 1) {
 400                 i = strlen(argv[0]) - strlen(ext);
 401                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
 402                         char *argv0 = strdup(argv[0]);
 403                         argv[0] = cmd = argv0;
 404                         argv0[i] = '\0';
 405                 }
 406         }
 407
 408         /* Turn "perf cmd --help" into "perf help cmd" */
 409         if (argc > 1 && !strcmp(argv[1], "--help")) {
 410                 argv[1] = argv[0];
 411                 argv[0] = cmd = "help";
 412         }
 413
 414         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 415                 struct cmd_struct *p = commands+i;
 416                 if (strcmp(p->cmd, cmd))
 417                         continue;
 418                 exit(run_builtin(p, argc, argv));
 419         }
 420 }
 421
 422 static void execv_dashed_external(const char **argv)
 423 {
 424         char *cmd;
 425         const char *tmp;
 426         int status;
 427
 428         if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
 429                 goto do_die;
 430
 431         /*
 432          * argv[0] must be the perf command, but the argv array
 433          * belongs to the caller, and may be reused in
 434          * subsequent loop iterations. Save argv[0] and
 435          * restore it on error.
 436          */
 437         tmp = argv[0];
 438         argv[0] = cmd;
 439
 440         /*
 441          * if we fail because the command is not found, it is
 442          * OK to return. Otherwise, we just pass along the status code.
 443          */
 444         status = run_command_v_opt(argv, 0);
 445         if (status != -ERR_RUN_COMMAND_EXEC) {
 446                 if (IS_RUN_COMMAND_ERR(status)) {
 447 do_die:
 448                         die("unable to run '%s'", argv[0]);
 449                 }
 450                 exit(-status);
 451         }
 452         errno = ENOENT; /* as if we called execvp */
 453
 454         argv[0] = tmp;
 455         zfree(&cmd);
 456 }
 457
 458 static int run_argv(int *argcp, const char ***argv)
 459 {
 460         int done_alias = 0;
 461
 462         while (1) {
 463                 /* See if it's an internal command */
 464                 handle_internal_command(*argcp, *argv);
 465
 466                 /* .. then try the external ones */
 467                 execv_dashed_external(*argv);
 468
 469                 /* It could be an alias -- this works around the insanity
 470                  * of overriding "perf log" with "perf show" by having
 471                  * alias.log = show
 472                  */
 473                 if (done_alias || !handle_alias(argcp, argv))
 474                         break;
 475                 done_alias = 1;
 476         }
 477
 478         return done_alias;
 479 }
 480
 481 static void pthread__block_sigwinch(void)
 482 {
 483         sigset_t set;
 484
 485         sigemptyset(&set);
 486         sigaddset(&set, SIGWINCH);
 487         pthread_sigmask(SIG_BLOCK, &set, NULL);
 488 }
 489
 490 void pthread__unblock_sigwinch(void)
 491 {
 492         sigset_t set;
 493
 494         sigemptyset(&set);
 495         sigaddset(&set, SIGWINCH);
 496         pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 497 }
 498
 499 #ifdef _SC_LEVEL1_DCACHE_LINESIZE
 500 #define cache_line_size(cacheline_sizep) *cacheline_sizep = sysconf(_SC_LEVEL1_DCACHE_LINESIZE)
 501 #else
 502 static void cache_line_size(int *cacheline_sizep)
 503 {
 504         if (sysfs__read_int("devices/system/cpu/cpu0/cache/index0/coherency_line_size", cacheline_sizep))
 505                 pr_debug("cannot determine cache line size");
 506 }
 507 #endif
 508
 509 int main(int argc, const char **argv)
 510 {
 511         const char *cmd;
 512         char sbuf[STRERR_BUFSIZE];
 513         int value;
 514
 515         /* libsubcmd init */
 516         exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
 517         pager_init(PERF_PAGER_ENVIRONMENT);
 518
 519         /* The page_size is placed in util object. */
 520         page_size = sysconf(_SC_PAGE_SIZE);
 521         cache_line_size(&cacheline_size);
 522
 523         if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
 524                 sysctl_perf_event_max_stack = value;
 525
 526         if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
 527                 sysctl_perf_event_max_contexts_per_stack = value;
 528
 529         cmd = extract_argv0_path(argv[0]);
 530         if (!cmd)
 531                 cmd = "perf-help";
 532
 533         srandom(time(NULL));
 534
 535         perf_config__init();
 536         perf_config(perf_default_config, NULL);
 537         set_buildid_dir(NULL);
 538
 539         /* get debugfs/tracefs mount point from /proc/mounts */
 540         tracing_path_mount();
 541
 542         /*
 543          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
 544          *
 545          *  - cannot take flags in between the "perf" and the "xxxx".
 546          *  - cannot execute it externally (since it would just do
 547          *    the same thing over again)
 548          *
 549          * So we just directly call the internal command handler, and
 550          * die if that one cannot handle it.
 551          */
 552         if (!prefixcmp(cmd, "perf-")) {
 553                 cmd += 5;
 554                 argv[0] = cmd;
 555                 handle_internal_command(argc, argv);
 556                 fprintf(stderr, "cannot handle %s internally", cmd);
 557                 goto out;
 558         }
 559         if (!prefixcmp(cmd, "trace")) {
 560 #ifdef HAVE_LIBAUDIT_SUPPORT
 561                 setup_path();
 562                 argv[0] = "trace";
 563                 return cmd_trace(argc, argv, NULL);
 564 #else
 565                 fprintf(stderr,
 566                         "trace command not available: missing audit-libs devel package at build time.\n");
 567                 goto out;
 568 #endif
 569         }
 570         /* Look for flags.. */
 571         argv++;
 572         argc--;
 573         handle_options(&argv, &argc, NULL);
 574         commit_pager_choice();
 575
 576         if (argc > 0) {
 577                 if (!prefixcmp(argv[0], "--"))
 578                         argv[0] += 2;
 579         } else {
 580                 /* The user didn't specify a command; give them help */
 581                 printf("\n usage: %s\n\n", perf_usage_string);
 582                 list_common_cmds_help();
 583                 printf("\n %s\n\n", perf_more_info_string);
 584                 goto out;
 585         }
 586         cmd = argv[0];
 587
 588         test_attr__init();
 589
 590         /*
 591          * We use PATH to find perf commands, but we prepend some higher
 592          * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
 593          * environment, and the $(perfexecdir) from the Makefile at build
 594          * time.
 595          */
 596         setup_path();
 597         /*
 598          * Block SIGWINCH notifications so that the thread that wants it can
 599          * unblock and get syscalls like select interrupted instead of waiting
 600          * forever while the signal goes to some other non interested thread.
 601          */
 602         pthread__block_sigwinch();
 603
 604         perf_debug_setup();
 605
 606         while (1) {
 607                 static int done_help;
 608                 int was_alias = run_argv(&argc, &argv);
 609
 610                 if (errno != ENOENT)
 611                         break;
 612
 613                 if (was_alias) {
 614                         fprintf(stderr, "Expansion of alias '%s' failed; "
 615                                 "'%s' is not a perf-command\n",
 616                                 cmd, argv[0]);
 617                         goto out;
 618                 }
 619                 if (!done_help) {
 620                         cmd = argv[0] = help_unknown_cmd(cmd);
 621                         done_help = 1;
 622                 } else
 623                         break;
 624         }
 625
 626         fprintf(stderr, "Failed to run command '%s': %s\n",
 627                 cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
 628 out:
 629         return 1;
 630 }