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