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 **);
  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         { "ftrace",     cmd_ftrace,     0 },
  75 };
  76
  77 struct pager_config {
  78         const char *cmd;
  79         int val;
  80 };
  81
  82 static int pager_command_config(const char *var, const char *value, void *data)
  83 {
  84         struct pager_config *c = data;
  85         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  86                 c->val = perf_config_bool(var, value);
  87         return 0;
  88 }
  89
  90 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  91 int check_pager_config(const char *cmd)
  92 {
  93         int err;
  94         struct pager_config c;
  95         c.cmd = cmd;
  96         c.val = -1;
  97         err = perf_config(pager_command_config, &c);
  98         return err ?: c.val;
  99 }
 100
 101 static int browser_command_config(const char *var, const char *value, void *data)
 102 {
 103         struct pager_config *c = data;
 104         if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
 105                 c->val = perf_config_bool(var, value);
 106         if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
 107                 c->val = perf_config_bool(var, value) ? 2 : 0;
 108         return 0;
 109 }
 110
 111 /*
 112  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
 113  * and -1 for "not specified"
 114  */
 115 static int check_browser_config(const char *cmd)
 116 {
 117         int err;
 118         struct pager_config c;
 119         c.cmd = cmd;
 120         c.val = -1;
 121         err = perf_config(browser_command_config, &c);
 122         return err ?: c.val;
 123 }
 124
 125 static void commit_pager_choice(void)
 126 {
 127         switch (use_pager) {
 128         case 0:
 129                 setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
 130                 break;
 131         case 1:
 132                 /* setup_pager(); */
 133                 break;
 134         default:
 135                 break;
 136         }
 137 }
 138
 139 struct option options[] = {
 140         OPT_ARGUMENT("help", "help"),
 141         OPT_ARGUMENT("version", "version"),
 142         OPT_ARGUMENT("exec-path", "exec-path"),
 143         OPT_ARGUMENT("html-path", "html-path"),
 144         OPT_ARGUMENT("paginate", "paginate"),
 145         OPT_ARGUMENT("no-pager", "no-pager"),
 146         OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
 147         OPT_ARGUMENT("buildid-dir", "buildid-dir"),
 148         OPT_ARGUMENT("list-cmds", "list-cmds"),
 149         OPT_ARGUMENT("list-opts", "list-opts"),
 150         OPT_ARGUMENT("debug", "debug"),
 151         OPT_END()
 152 };
 153
 154 static int handle_options(const char ***argv, int *argc, int *envchanged)
 155 {
 156         int handled = 0;
 157
 158         while (*argc > 0) {
 159                 const char *cmd = (*argv)[0];
 160                 if (cmd[0] != '-')
 161                         break;
 162
 163                 /*
 164                  * For legacy reasons, the "version" and "help"
 165                  * commands can be written with "--" prepended
 166                  * to make them look like flags.
 167                  */
 168                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 169                         break;
 170
 171                 /*
 172                  * Shortcut for '-h' and '-v' options to invoke help
 173                  * and version command.
 174                  */
 175                 if (!strcmp(cmd, "-h")) {
 176                         (*argv)[0] = "--help";
 177                         break;
 178                 }
 179
 180                 if (!strcmp(cmd, "-v")) {
 181                         (*argv)[0] = "--version";
 182                         break;
 183                 }
 184
 185                 /*
 186                  * Check remaining flags.
 187                  */
 188                 if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
 189                         cmd += strlen(CMD_EXEC_PATH);
 190                         if (*cmd == '=')
 191                                 set_argv_exec_path(cmd + 1);
 192                         else {
 193                                 puts(get_argv_exec_path());
 194                                 exit(0);
 195                         }
 196                 } else if (!strcmp(cmd, "--html-path")) {
 197                         puts(system_path(PERF_HTML_PATH));
 198                         exit(0);
 199                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 200                         use_pager = 1;
 201                 } else if (!strcmp(cmd, "--no-pager")) {
 202                         use_pager = 0;
 203                         if (envchanged)
 204                                 *envchanged = 1;
 205                 } else if (!strcmp(cmd, "--debugfs-dir")) {
 206                         if (*argc < 2) {
 207                                 fprintf(stderr, "No directory given for --debugfs-dir.\n");
 208                                 usage(perf_usage_string);
 209                         }
 210                         tracing_path_set((*argv)[1]);
 211                         if (envchanged)
 212                                 *envchanged = 1;
 213                         (*argv)++;
 214                         (*argc)--;
 215                 } else if (!strcmp(cmd, "--buildid-dir")) {
 216                         if (*argc < 2) {
 217                                 fprintf(stderr, "No directory given for --buildid-dir.\n");
 218                                 usage(perf_usage_string);
 219                         }
 220                         set_buildid_dir((*argv)[1]);
 221                         if (envchanged)
 222                                 *envchanged = 1;
 223                         (*argv)++;
 224                         (*argc)--;
 225                 } else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
 226                         tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
 227                         fprintf(stderr, "dir: %s\n", tracing_path);
 228                         if (envchanged)
 229                                 *envchanged = 1;
 230                 } else if (!strcmp(cmd, "--list-cmds")) {
 231                         unsigned int i;
 232
 233                         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 234                                 struct cmd_struct *p = commands+i;
 235                                 printf("%s ", p->cmd);
 236                         }
 237                         putchar('\n');
 238                         exit(0);
 239                 } else if (!strcmp(cmd, "--list-opts")) {
 240                         unsigned int i;
 241
 242                         for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
 243                                 struct option *p = options+i;
 244                                 printf("--%s ", p->long_name);
 245                         }
 246                         putchar('\n');
 247                         exit(0);
 248                 } else if (!strcmp(cmd, "--debug")) {
 249                         if (*argc < 2) {
 250                                 fprintf(stderr, "No variable specified for --debug.\n");
 251                                 usage(perf_usage_string);
 252                         }
 253                         if (perf_debug_option((*argv)[1]))
 254                                 usage(perf_usage_string);
 255
 256                         (*argv)++;
 257                         (*argc)--;
 258                 } else {
 259                         fprintf(stderr, "Unknown option: %s\n", cmd);
 260                         usage(perf_usage_string);
 261                 }
 262
 263                 (*argv)++;
 264                 (*argc)--;
 265                 handled++;
 266         }
 267         return handled;
 268 }
 269
 270 static int handle_alias(int *argcp, const char ***argv)
 271 {
 272         int envchanged = 0, ret = 0, saved_errno = errno;
 273         int count, option_count;
 274         const char **new_argv;
 275         const char *alias_command;
 276         char *alias_string;
 277
 278         alias_command = (*argv)[0];
 279         alias_string = alias_lookup(alias_command);
 280         if (alias_string) {
 281                 if (alias_string[0] == '!') {
 282                         if (*argcp > 1) {
 283                                 struct strbuf buf;
 284
 285                                 if (strbuf_init(&buf, PATH_MAX) < 0 ||
 286                                     strbuf_addstr(&buf, alias_string) < 0 ||
 287                                     sq_quote_argv(&buf, (*argv) + 1,
 288                                                   PATH_MAX) < 0)
 289                                         die("Failed to allocate memory.");
 290                                 free(alias_string);
 291                                 alias_string = buf.buf;
 292                         }
 293                         ret = system(alias_string + 1);
 294                         if (ret >= 0 && WIFEXITED(ret) &&
 295                             WEXITSTATUS(ret) != 127)
 296                                 exit(WEXITSTATUS(ret));
 297                         die("Failed to run '%s' when expanding alias '%s'",
 298                             alias_string + 1, alias_command);
 299                 }
 300                 count = split_cmdline(alias_string, &new_argv);
 301                 if (count < 0)
 302                         die("Bad alias.%s string", alias_command);
 303                 option_count = handle_options(&new_argv, &count, &envchanged);
 304                 if (envchanged)
 305                         die("alias '%s' changes environment variables\n"
 306                                  "You can use '!perf' in the alias to do this.",
 307                                  alias_command);
 308                 memmove(new_argv - option_count, new_argv,
 309                                 count * sizeof(char *));
 310                 new_argv -= option_count;
 311
 312                 if (count < 1)
 313                         die("empty alias for %s", alias_command);
 314
 315                 if (!strcmp(alias_command, new_argv[0]))
 316                         die("recursive alias: %s", alias_command);
 317
 318                 new_argv = realloc(new_argv, sizeof(char *) *
 319                                     (count + *argcp + 1));
 320                 /* insert after command name */
 321                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 322                 new_argv[count + *argcp] = NULL;
 323
 324                 *argv = new_argv;
 325                 *argcp += count - 1;
 326
 327                 ret = 1;
 328         }
 329
 330         errno = saved_errno;
 331
 332         return ret;
 333 }
 334
 335 #define RUN_SETUP       (1<<0)
 336 #define USE_PAGER       (1<<1)
 337
 338 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 339 {
 340         int status;
 341         struct stat st;
 342         char sbuf[STRERR_BUFSIZE];
 343
 344         if (use_browser == -1)
 345                 use_browser = check_browser_config(p->cmd);
 346
 347         if (use_pager == -1 && p->option & RUN_SETUP)
 348                 use_pager = check_pager_config(p->cmd);
 349         if (use_pager == -1 && p->option & USE_PAGER)
 350                 use_pager = 1;
 351         commit_pager_choice();
 352
 353         perf_env__set_cmdline(&perf_env, argc, argv);
 354         status = p->fn(argc, argv);
 355         perf_config__exit();
 356         exit_browser(status);
 357         perf_env__exit(&perf_env);
 358         bpf__clear();
 359
 360         if (status)
 361                 return status & 0xff;
 362
 363         /* Somebody closed stdout? */
 364         if (fstat(fileno(stdout), &st))
 365                 return 0;
 366         /* Ignore write errors for pipes and sockets.. */
 367         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 368                 return 0;
 369
 370         status = 1;
 371         /* Check for ENOSPC and EIO errors.. */
 372         if (fflush(stdout)) {
 373                 fprintf(stderr, "write failure on standard output: %s",
 374                         str_error_r(errno, sbuf, sizeof(sbuf)));
 375                 goto out;
 376         }
 377         if (ferror(stdout)) {
 378                 fprintf(stderr, "unknown write failure on standard output");
 379                 goto out;
 380         }
 381         if (fclose(stdout)) {
 382                 fprintf(stderr, "close failed on standard output: %s",
 383                         str_error_r(errno, sbuf, sizeof(sbuf)));
 384                 goto out;
 385         }
 386         status = 0;
 387 out:
 388         return status;
 389 }
 390
 391 static void handle_internal_command(int argc, const char **argv)
 392 {
 393         const char *cmd = argv[0];
 394         unsigned int i;
 395         static const char ext[] = STRIP_EXTENSION;
 396
 397         if (sizeof(ext) > 1) {
 398                 i = strlen(argv[0]) - strlen(ext);
 399                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
 400                         char *argv0 = strdup(argv[0]);
 401                         argv[0] = cmd = argv0;
 402                         argv0[i] = '\0';
 403                 }
 404         }
 405
 406         /* Turn "perf cmd --help" into "perf help cmd" */
 407         if (argc > 1 && !strcmp(argv[1], "--help")) {
 408                 argv[1] = argv[0];
 409                 argv[0] = cmd = "help";
 410         }
 411
 412         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 413                 struct cmd_struct *p = commands+i;
 414                 if (strcmp(p->cmd, cmd))
 415                         continue;
 416                 exit(run_builtin(p, argc, argv));
 417         }
 418 }
 419
 420 static void execv_dashed_external(const char **argv)
 421 {
 422         char *cmd;
 423         const char *tmp;
 424         int status;
 425
 426         if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
 427                 goto do_die;
 428
 429         /*
 430          * argv[0] must be the perf command, but the argv array
 431          * belongs to the caller, and may be reused in
 432          * subsequent loop iterations. Save argv[0] and
 433          * restore it on error.
 434          */
 435         tmp = argv[0];
 436         argv[0] = cmd;
 437
 438         /*
 439          * if we fail because the command is not found, it is
 440          * OK to return. Otherwise, we just pass along the status code.
 441          */
 442         status = run_command_v_opt(argv, 0);
 443         if (status != -ERR_RUN_COMMAND_EXEC) {
 444                 if (IS_RUN_COMMAND_ERR(status)) {
 445 do_die:
 446                         die("unable to run '%s'", argv[0]);
 447                 }
 448                 exit(-status);
 449         }
 450         errno = ENOENT; /* as if we called execvp */
 451
 452         argv[0] = tmp;
 453         zfree(&cmd);
 454 }
 455
 456 static int run_argv(int *argcp, const char ***argv)
 457 {
 458         int done_alias = 0;
 459
 460         while (1) {
 461                 /* See if it's an internal command */
 462                 handle_internal_command(*argcp, *argv);
 463
 464                 /* .. then try the external ones */
 465                 execv_dashed_external(*argv);
 466
 467                 /* It could be an alias -- this works around the insanity
 468                  * of overriding "perf log" with "perf show" by having
 469                  * alias.log = show
 470                  */
 471                 if (done_alias || !handle_alias(argcp, argv))
 472                         break;
 473                 done_alias = 1;
 474         }
 475
 476         return done_alias;
 477 }
 478
 479 static void pthread__block_sigwinch(void)
 480 {
 481         sigset_t set;
 482
 483         sigemptyset(&set);
 484         sigaddset(&set, SIGWINCH);
 485         pthread_sigmask(SIG_BLOCK, &set, NULL);
 486 }
 487
 488 void pthread__unblock_sigwinch(void)
 489 {
 490         sigset_t set;
 491
 492         sigemptyset(&set);
 493         sigaddset(&set, SIGWINCH);
 494         pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 495 }
 496
 497 #ifdef _SC_LEVEL1_DCACHE_LINESIZE
 498 #define cache_line_size(cacheline_sizep) *cacheline_sizep = sysconf(_SC_LEVEL1_DCACHE_LINESIZE)
 499 #else
 500 static void cache_line_size(int *cacheline_sizep)
 501 {
 502         if (sysfs__read_int("devices/system/cpu/cpu0/cache/index0/coherency_line_size", cacheline_sizep))
 503                 pr_debug("cannot determine cache line size");
 504 }
 505 #endif
 506
 507 int main(int argc, const char **argv)
 508 {
 509         int err;
 510         const char *cmd;
 511         char sbuf[STRERR_BUFSIZE];
 512         int value;
 513
 514         /* libsubcmd init */
 515         exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
 516         pager_init(PERF_PAGER_ENVIRONMENT);
 517
 518         /* The page_size is placed in util object. */
 519         page_size = sysconf(_SC_PAGE_SIZE);
 520         cache_line_size(&cacheline_size);
 521
 522         if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
 523                 sysctl_perf_event_max_stack = value;
 524
 525         if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
 526                 sysctl_perf_event_max_contexts_per_stack = value;
 527
 528         cmd = extract_argv0_path(argv[0]);
 529         if (!cmd)
 530                 cmd = "perf-help";
 531
 532         srandom(time(NULL));
 533
 534         perf_config__init();
 535         err = perf_config(perf_default_config, NULL);
 536         if (err)
 537                 return err;
 538         set_buildid_dir(NULL);
 539
 540         /* get debugfs/tracefs mount point from /proc/mounts */
 541         tracing_path_mount();
 542
 543         /*
 544          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
 545          *
 546          *  - cannot take flags in between the "perf" and the "xxxx".
 547          *  - cannot execute it externally (since it would just do
 548          *    the same thing over again)
 549          *
 550          * So we just directly call the internal command handler, and
 551          * die if that one cannot handle it.
 552          */
 553         if (!prefixcmp(cmd, "perf-")) {
 554                 cmd += 5;
 555                 argv[0] = cmd;
 556                 handle_internal_command(argc, argv);
 557                 fprintf(stderr, "cannot handle %s internally", cmd);
 558                 goto out;
 559         }
 560         if (!prefixcmp(cmd, "trace")) {
 561 #ifdef HAVE_LIBAUDIT_SUPPORT
 562                 setup_path();
 563                 argv[0] = "trace";
 564                 return cmd_trace(argc, argv);
 565 #else
 566                 fprintf(stderr,
 567                         "trace command not available: missing audit-libs devel package at build time.\n");
 568                 goto out;
 569 #endif
 570         }
 571         /* Look for flags.. */
 572         argv++;
 573         argc--;
 574         handle_options(&argv, &argc, NULL);
 575         commit_pager_choice();
 576
 577         if (argc > 0) {
 578                 if (!prefixcmp(argv[0], "--"))
 579                         argv[0] += 2;
 580         } else {
 581                 /* The user didn't specify a command; give them help */
 582                 printf("\n usage: %s\n\n", perf_usage_string);
 583                 list_common_cmds_help();
 584                 printf("\n %s\n\n", perf_more_info_string);
 585                 goto out;
 586         }
 587         cmd = argv[0];
 588
 589         test_attr__init();
 590
 591         /*
 592          * We use PATH to find perf commands, but we prepend some higher
 593          * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
 594          * environment, and the $(perfexecdir) from the Makefile at build
 595          * time.
 596          */
 597         setup_path();
 598         /*
 599          * Block SIGWINCH notifications so that the thread that wants it can
 600          * unblock and get syscalls like select interrupted instead of waiting
 601          * forever while the signal goes to some other non interested thread.
 602          */
 603         pthread__block_sigwinch();
 604
 605         perf_debug_setup();
 606
 607         while (1) {
 608                 static int done_help;
 609                 int was_alias = run_argv(&argc, &argv);
 610
 611                 if (errno != ENOENT)
 612                         break;
 613
 614                 if (was_alias) {
 615                         fprintf(stderr, "Expansion of alias '%s' failed; "
 616                                 "'%s' is not a perf-command\n",
 617                                 cmd, argv[0]);
 618                         goto out;
 619                 }
 620                 if (!done_help) {
 621                         cmd = argv[0] = help_unknown_cmd(cmd);
 622                         done_help = 1;
 623                 } else
 624                         break;
 625         }
 626
 627         fprintf(stderr, "Failed to run command '%s': %s\n",
 628                 cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
 629 out:
 630         return 1;
 631 }