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