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