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