kernel/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/exec_cmd.h"
  12 #include "util/cache.h"
  13 #include "util/quote.h"
  14 #include "util/run-command.h"
  15 #include "util/parse-events.h"
  16 #include "util/parse-options.h"
  17 #include "util/debug.h"
  18 #include <api/fs/debugfs.h>
  19 #include <pthread.h>
  20
  21 const char perf_usage_string[] =
  22         "perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
  23
  24 const char perf_more_info_string[] =
  25         "See 'perf help COMMAND' for more information on a specific command.";
  26
  27 int use_browser = -1;
  28 static int use_pager = -1;
  29 const char *input_name;
  30
  31 struct cmd_struct {
  32         const char *cmd;
  33         int (*fn)(int, const char **, const char *);
  34         int option;
  35 };
  36
  37 static struct cmd_struct commands[] = {
  38         { "buildid-cache", cmd_buildid_cache, 0 },
  39         { "buildid-list", cmd_buildid_list, 0 },
  40         { "diff",       cmd_diff,       0 },
  41         { "evlist",     cmd_evlist,     0 },
  42         { "help",       cmd_help,       0 },
  43         { "list",       cmd_list,       0 },
  44         { "record",     cmd_record,     0 },
  45         { "report",     cmd_report,     0 },
  46         { "bench",      cmd_bench,      0 },
  47         { "stat",       cmd_stat,       0 },
  48         { "timechart",  cmd_timechart,  0 },
  49         { "top",        cmd_top,        0 },
  50         { "annotate",   cmd_annotate,   0 },
  51         { "version",    cmd_version,    0 },
  52         { "script",     cmd_script,     0 },
  53         { "sched",      cmd_sched,      0 },
  54 #ifdef HAVE_LIBELF_SUPPORT
  55         { "probe",      cmd_probe,      0 },
  56 #endif
  57         { "kmem",       cmd_kmem,       0 },
  58         { "lock",       cmd_lock,       0 },
  59         { "kvm",        cmd_kvm,        0 },
  60         { "test",       cmd_test,       0 },
  61 #ifdef HAVE_LIBAUDIT_SUPPORT
  62         { "trace",      cmd_trace,      0 },
  63 #endif
  64         { "inject",     cmd_inject,     0 },
  65         { "mem",        cmd_mem,        0 },
  66         { "data",       cmd_data,       0 },
  67 };
  68
  69 struct pager_config {
  70         const char *cmd;
  71         int val;
  72 };
  73
  74 static int pager_command_config(const char *var, const char *value, void *data)
  75 {
  76         struct pager_config *c = data;
  77         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  78                 c->val = perf_config_bool(var, value);
  79         return 0;
  80 }
  81
  82 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  83 int check_pager_config(const char *cmd)
  84 {
  85         struct pager_config c;
  86         c.cmd = cmd;
  87         c.val = -1;
  88         perf_config(pager_command_config, &c);
  89         return c.val;
  90 }
  91
  92 static int browser_command_config(const char *var, const char *value, void *data)
  93 {
  94         struct pager_config *c = data;
  95         if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
  96                 c->val = perf_config_bool(var, value);
  97         if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
  98                 c->val = perf_config_bool(var, value) ? 2 : 0;
  99         return 0;
 100 }
 101
 102 /*
 103  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
 104  * and -1 for "not specified"
 105  */
 106 static int check_browser_config(const char *cmd)
 107 {
 108         struct pager_config c;
 109         c.cmd = cmd;
 110         c.val = -1;
 111         perf_config(browser_command_config, &c);
 112         return c.val;
 113 }
 114
 115 static void commit_pager_choice(void)
 116 {
 117         switch (use_pager) {
 118         case 0:
 119                 setenv("PERF_PAGER", "cat", 1);
 120                 break;
 121         case 1:
 122                 /* setup_pager(); */
 123                 break;
 124         default:
 125                 break;
 126         }
 127 }
 128
 129 struct option options[] = {
 130         OPT_ARGUMENT("help", "help"),
 131         OPT_ARGUMENT("version", "version"),
 132         OPT_ARGUMENT("exec-path", "exec-path"),
 133         OPT_ARGUMENT("html-path", "html-path"),
 134         OPT_ARGUMENT("paginate", "paginate"),
 135         OPT_ARGUMENT("no-pager", "no-pager"),
 136         OPT_ARGUMENT("perf-dir", "perf-dir"),
 137         OPT_ARGUMENT("work-tree", "work-tree"),
 138         OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
 139         OPT_ARGUMENT("buildid-dir", "buildid-dir"),
 140         OPT_ARGUMENT("list-cmds", "list-cmds"),
 141         OPT_ARGUMENT("list-opts", "list-opts"),
 142         OPT_ARGUMENT("debug", "debug"),
 143         OPT_END()
 144 };
 145
 146 static int handle_options(const char ***argv, int *argc, int *envchanged)
 147 {
 148         int handled = 0;
 149
 150         while (*argc > 0) {
 151                 const char *cmd = (*argv)[0];
 152                 if (cmd[0] != '-')
 153                         break;
 154
 155                 /*
 156                  * For legacy reasons, the "version" and "help"
 157                  * commands can be written with "--" prepended
 158                  * to make them look like flags.
 159                  */
 160                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 161                         break;
 162
 163                 /*
 164                  * Check remaining flags.
 165                  */
 166                 if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
 167                         cmd += strlen(CMD_EXEC_PATH);
 168                         if (*cmd == '=')
 169                                 perf_set_argv_exec_path(cmd + 1);
 170                         else {
 171                                 puts(perf_exec_path());
 172                                 exit(0);
 173                         }
 174                 } else if (!strcmp(cmd, "--html-path")) {
 175                         puts(system_path(PERF_HTML_PATH));
 176                         exit(0);
 177                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 178                         use_pager = 1;
 179                 } else if (!strcmp(cmd, "--no-pager")) {
 180                         use_pager = 0;
 181                         if (envchanged)
 182                                 *envchanged = 1;
 183                 } else if (!strcmp(cmd, "--perf-dir")) {
 184                         if (*argc < 2) {
 185                                 fprintf(stderr, "No directory given for --perf-dir.\n");
 186                                 usage(perf_usage_string);
 187                         }
 188                         setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
 189                         if (envchanged)
 190                                 *envchanged = 1;
 191                         (*argv)++;
 192                         (*argc)--;
 193                         handled++;
 194                 } else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
 195                         setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
 196                         if (envchanged)
 197                                 *envchanged = 1;
 198                 } else if (!strcmp(cmd, "--work-tree")) {
 199                         if (*argc < 2) {
 200                                 fprintf(stderr, "No directory given for --work-tree.\n");
 201                                 usage(perf_usage_string);
 202                         }
 203                         setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 204                         if (envchanged)
 205                                 *envchanged = 1;
 206                         (*argv)++;
 207                         (*argc)--;
 208                 } else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
 209                         setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
 210                         if (envchanged)
 211                                 *envchanged = 1;
 212                 } else if (!strcmp(cmd, "--debugfs-dir")) {
 213                         if (*argc < 2) {
 214                                 fprintf(stderr, "No directory given for --debugfs-dir.\n");
 215                                 usage(perf_usage_string);
 216                         }
 217                         perf_debugfs_set_path((*argv)[1]);
 218                         if (envchanged)
 219                                 *envchanged = 1;
 220                         (*argv)++;
 221                         (*argc)--;
 222                 } else if (!strcmp(cmd, "--buildid-dir")) {
 223                         if (*argc < 2) {
 224                                 fprintf(stderr, "No directory given for --buildid-dir.\n");
 225                                 usage(perf_usage_string);
 226                         }
 227                         set_buildid_dir((*argv)[1]);
 228                         if (envchanged)
 229                                 *envchanged = 1;
 230                         (*argv)++;
 231                         (*argc)--;
 232                 } else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
 233                         perf_debugfs_set_path(cmd + strlen(CMD_DEBUGFS_DIR));
 234                         fprintf(stderr, "dir: %s\n", debugfs_mountpoint);
 235                         if (envchanged)
 236                                 *envchanged = 1;
 237                 } else if (!strcmp(cmd, "--list-cmds")) {
 238                         unsigned int i;
 239
 240                         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 241                                 struct cmd_struct *p = commands+i;
 242                                 printf("%s ", p->cmd);
 243                         }
 244                         putchar('\n');
 245                         exit(0);
 246                 } else if (!strcmp(cmd, "--list-opts")) {
 247                         unsigned int i;
 248
 249                         for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
 250                                 struct option *p = options+i;
 251                                 printf("--%s ", p->long_name);
 252                         }
 253                         putchar('\n');
 254                         exit(0);
 255                 } else if (!strcmp(cmd, "--debug")) {
 256                         if (*argc < 2) {
 257                                 fprintf(stderr, "No variable specified for --debug.\n");
 258                                 usage(perf_usage_string);
 259                         }
 260                         if (perf_debug_option((*argv)[1]))
 261                                 usage(perf_usage_string);
 262
 263                         (*argv)++;
 264                         (*argc)--;
 265                 } else {
 266                         fprintf(stderr, "Unknown option: %s\n", cmd);
 267                         usage(perf_usage_string);
 268                 }
 269
 270                 (*argv)++;
 271                 (*argc)--;
 272                 handled++;
 273         }
 274         return handled;
 275 }
 276
 277 static int handle_alias(int *argcp, const char ***argv)
 278 {
 279         int envchanged = 0, ret = 0, saved_errno = errno;
 280         int count, option_count;
 281         const char **new_argv;
 282         const char *alias_command;
 283         char *alias_string;
 284
 285         alias_command = (*argv)[0];
 286         alias_string = alias_lookup(alias_command);
 287         if (alias_string) {
 288                 if (alias_string[0] == '!') {
 289                         if (*argcp > 1) {
 290                                 struct strbuf buf;
 291
 292                                 strbuf_init(&buf, PATH_MAX);
 293                                 strbuf_addstr(&buf, alias_string);
 294                                 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
 295                                 free(alias_string);
 296                                 alias_string = buf.buf;
 297                         }
 298                         ret = system(alias_string + 1);
 299                         if (ret >= 0 && WIFEXITED(ret) &&
 300                             WEXITSTATUS(ret) != 127)
 301                                 exit(WEXITSTATUS(ret));
 302                         die("Failed to run '%s' when expanding alias '%s'",
 303                             alias_string + 1, alias_command);
 304                 }
 305                 count = split_cmdline(alias_string, &new_argv);
 306                 if (count < 0)
 307                         die("Bad alias.%s string", alias_command);
 308                 option_count = handle_options(&new_argv, &count, &envchanged);
 309                 if (envchanged)
 310                         die("alias '%s' changes environment variables\n"
 311                                  "You can use '!perf' in the alias to do this.",
 312                                  alias_command);
 313                 memmove(new_argv - option_count, new_argv,
 314                                 count * sizeof(char *));
 315                 new_argv -= option_count;
 316
 317                 if (count < 1)
 318                         die("empty alias for %s", alias_command);
 319
 320                 if (!strcmp(alias_command, new_argv[0]))
 321                         die("recursive alias: %s", alias_command);
 322
 323                 new_argv = realloc(new_argv, sizeof(char *) *
 324                                     (count + *argcp + 1));
 325                 /* insert after command name */
 326                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 327                 new_argv[count + *argcp] = NULL;
 328
 329                 *argv = new_argv;
 330                 *argcp += count - 1;
 331
 332                 ret = 1;
 333         }
 334
 335         errno = saved_errno;
 336
 337         return ret;
 338 }
 339
 340 const char perf_version_string[] = PERF_VERSION;
 341
 342 #define RUN_SETUP       (1<<0)
 343 #define USE_PAGER       (1<<1)
 344 /*
 345  * require working tree to be present -- anything uses this needs
 346  * RUN_SETUP for reading from the configuration file.
 347  */
 348 #define NEED_WORK_TREE  (1<<2)
 349
 350 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 351 {
 352         int status;
 353         struct stat st;
 354         const char *prefix;
 355         char sbuf[STRERR_BUFSIZE];
 356
 357         prefix = NULL;
 358         if (p->option & RUN_SETUP)
 359                 prefix = NULL; /* setup_perf_directory(); */
 360
 361         if (use_browser == -1)
 362                 use_browser = check_browser_config(p->cmd);
 363
 364         if (use_pager == -1 && p->option & RUN_SETUP)
 365                 use_pager = check_pager_config(p->cmd);
 366         if (use_pager == -1 && p->option & USE_PAGER)
 367                 use_pager = 1;
 368         commit_pager_choice();
 369
 370         status = p->fn(argc, argv, prefix);
 371         exit_browser(status);
 372
 373         if (status)
 374                 return status & 0xff;
 375
 376         /* Somebody closed stdout? */
 377         if (fstat(fileno(stdout), &st))
 378                 return 0;
 379         /* Ignore write errors for pipes and sockets.. */
 380         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 381                 return 0;
 382
 383         status = 1;
 384         /* Check for ENOSPC and EIO errors.. */
 385         if (fflush(stdout)) {
 386                 fprintf(stderr, "write failure on standard output: %s",
 387                         strerror_r(errno, sbuf, sizeof(sbuf)));
 388                 goto out;
 389         }
 390         if (ferror(stdout)) {
 391                 fprintf(stderr, "unknown write failure on standard output");
 392                 goto out;
 393         }
 394         if (fclose(stdout)) {
 395                 fprintf(stderr, "close failed on standard output: %s",
 396                         strerror_r(errno, sbuf, sizeof(sbuf)));
 397                 goto out;
 398         }
 399         status = 0;
 400 out:
 401         return status;
 402 }
 403
 404 static void handle_internal_command(int argc, const char **argv)
 405 {
 406         const char *cmd = argv[0];
 407         unsigned int i;
 408         static const char ext[] = STRIP_EXTENSION;
 409
 410         if (sizeof(ext) > 1) {
 411                 i = strlen(argv[0]) - strlen(ext);
 412                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
 413                         char *argv0 = strdup(argv[0]);
 414                         argv[0] = cmd = argv0;
 415                         argv0[i] = '\0';
 416                 }
 417         }
 418
 419         /* Turn "perf cmd --help" into "perf help cmd" */
 420         if (argc > 1 && !strcmp(argv[1], "--help")) {
 421                 argv[1] = argv[0];
 422                 argv[0] = cmd = "help";
 423         }
 424
 425         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 426                 struct cmd_struct *p = commands+i;
 427                 if (strcmp(p->cmd, cmd))
 428                         continue;
 429                 exit(run_builtin(p, argc, argv));
 430         }
 431 }
 432
 433 static void execv_dashed_external(const char **argv)
 434 {
 435         struct strbuf cmd = STRBUF_INIT;
 436         const char *tmp;
 437         int status;
 438
 439         strbuf_addf(&cmd, "perf-%s", argv[0]);
 440
 441         /*
 442          * argv[0] must be the perf command, but the argv array
 443          * belongs to the caller, and may be reused in
 444          * subsequent loop iterations. Save argv[0] and
 445          * restore it on error.
 446          */
 447         tmp = argv[0];
 448         argv[0] = cmd.buf;
 449
 450         /*
 451          * if we fail because the command is not found, it is
 452          * OK to return. Otherwise, we just pass along the status code.
 453          */
 454         status = run_command_v_opt(argv, 0);
 455         if (status != -ERR_RUN_COMMAND_EXEC) {
 456                 if (IS_RUN_COMMAND_ERR(status))
 457                         die("unable to run '%s'", argv[0]);
 458                 exit(-status);
 459         }
 460         errno = ENOENT; /* as if we called execvp */
 461
 462         argv[0] = tmp;
 463
 464         strbuf_release(&cmd);
 465 }
 466
 467 static int run_argv(int *argcp, const char ***argv)
 468 {
 469         int done_alias = 0;
 470
 471         while (1) {
 472                 /* See if it's an internal command */
 473                 handle_internal_command(*argcp, *argv);
 474
 475                 /* .. then try the external ones */
 476                 execv_dashed_external(*argv);
 477
 478                 /* It could be an alias -- this works around the insanity
 479                  * of overriding "perf log" with "perf show" by having
 480                  * alias.log = show
 481                  */
 482                 if (done_alias || !handle_alias(argcp, argv))
 483                         break;
 484                 done_alias = 1;
 485         }
 486
 487         return done_alias;
 488 }
 489
 490 static void pthread__block_sigwinch(void)
 491 {
 492         sigset_t set;
 493
 494         sigemptyset(&set);
 495         sigaddset(&set, SIGWINCH);
 496         pthread_sigmask(SIG_BLOCK, &set, NULL);
 497 }
 498
 499 void pthread__unblock_sigwinch(void)
 500 {
 501         sigset_t set;
 502
 503         sigemptyset(&set);
 504         sigaddset(&set, SIGWINCH);
 505         pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 506 }
 507
 508 int main(int argc, const char **argv)
 509 {
 510         const char *cmd;
 511         char sbuf[STRERR_BUFSIZE];
 512
 513         /* The page_size is placed in util object. */
 514         page_size = sysconf(_SC_PAGE_SIZE);
 515         cacheline_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
 516
 517         cmd = perf_extract_argv0_path(argv[0]);
 518         if (!cmd)
 519                 cmd = "perf-help";
 520         /* get debugfs mount point from /proc/mounts */
 521         perf_debugfs_mount(NULL);
 522         /*
 523          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
 524          *
 525          *  - cannot take flags in between the "perf" and the "xxxx".
 526          *  - cannot execute it externally (since it would just do
 527          *    the same thing over again)
 528          *
 529          * So we just directly call the internal command handler, and
 530          * die if that one cannot handle it.
 531          */
 532         if (!prefixcmp(cmd, "perf-")) {
 533                 cmd += 5;
 534                 argv[0] = cmd;
 535                 handle_internal_command(argc, argv);
 536                 fprintf(stderr, "cannot handle %s internally", cmd);
 537                 goto out;
 538         }
 539         if (!prefixcmp(cmd, "trace")) {
 540 #ifdef HAVE_LIBAUDIT_SUPPORT
 541                 set_buildid_dir(NULL);
 542                 setup_path();
 543                 argv[0] = "trace";
 544                 return cmd_trace(argc, argv, NULL);
 545 #else
 546                 fprintf(stderr,
 547                         "trace command not available: missing audit-libs devel package at build time.\n");
 548                 goto out;
 549 #endif
 550         }
 551         /* Look for flags.. */
 552         argv++;
 553         argc--;
 554         handle_options(&argv, &argc, NULL);
 555         commit_pager_choice();
 556         set_buildid_dir(NULL);
 557
 558         if (argc > 0) {
 559                 if (!prefixcmp(argv[0], "--"))
 560                         argv[0] += 2;
 561         } else {
 562                 /* The user didn't specify a command; give them help */
 563                 printf("\n usage: %s\n\n", perf_usage_string);
 564                 list_common_cmds_help();
 565                 printf("\n %s\n\n", perf_more_info_string);
 566                 goto out;
 567         }
 568         cmd = argv[0];
 569
 570         test_attr__init();
 571
 572         /*
 573          * We use PATH to find perf commands, but we prepend some higher
 574          * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
 575          * environment, and the $(perfexecdir) from the Makefile at build
 576          * time.
 577          */
 578         setup_path();
 579         /*
 580          * Block SIGWINCH notifications so that the thread that wants it can
 581          * unblock and get syscalls like select interrupted instead of waiting
 582          * forever while the signal goes to some other non interested thread.
 583          */
 584         pthread__block_sigwinch();
 585
 586         while (1) {
 587                 static int done_help;
 588                 int was_alias = run_argv(&argc, &argv);
 589
 590                 if (errno != ENOENT)
 591                         break;
 592
 593                 if (was_alias) {
 594                         fprintf(stderr, "Expansion of alias '%s' failed; "
 595                                 "'%s' is not a perf-command\n",
 596                                 cmd, argv[0]);
 597                         goto out;
 598                 }
 599                 if (!done_help) {
 600                         cmd = argv[0] = help_unknown_cmd(cmd);
 601                         done_help = 1;
 602                 } else
 603                         break;
 604         }
 605
 606         fprintf(stderr, "Failed to run command '%s': %s\n",
 607                 cmd, strerror_r(errno, sbuf, sizeof(sbuf)));
 608 out:
 609         return 1;
 610 }