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