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/env.h"
  12 #include <subcmd/exec-cmd.h>
  13 #include "util/config.h"
  14 #include "util/quote.h"
  15 #include <subcmd/run-command.h>
  16 #include "util/parse-events.h"
  17 #include <subcmd/parse-options.h>
  18 #include "util/bpf-loader.h"
  19 #include "util/debug.h"
  20 #include <api/fs/fs.h>
  21 #include <api/fs/tracing_path.h>
  22 #include <errno.h>
  23 #include <pthread.h>
  24 #include <signal.h>
  25 #include <stdlib.h>
  26 #include <time.h>
  27 #include <sys/types.h>
  28 #include <sys/stat.h>
  29 #include <unistd.h>
  30 #include <linux/kernel.h>
  31
  32 const char perf_usage_string[] =
  33         "perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
  34
  35 const char perf_more_info_string[] =
  36         "See 'perf help COMMAND' for more information on a specific command.";
  37
  38 static int use_pager = -1;
  39 const char *input_name;
  40
  41 struct cmd_struct {
  42         const char *cmd;
  43         int (*fn)(int, const char **);
  44         int option;
  45 };
  46
  47 static struct cmd_struct commands[] = {
  48         { "buildid-cache", cmd_buildid_cache, 0 },
  49         { "buildid-list", cmd_buildid_list, 0 },
  50         { "config",     cmd_config,     0 },
  51         { "c2c",        cmd_c2c,        0 },
  52         { "diff",       cmd_diff,       0 },
  53         { "evlist",     cmd_evlist,     0 },
  54         { "help",       cmd_help,       0 },
  55         { "kallsyms",   cmd_kallsyms,   0 },
  56         { "list",       cmd_list,       0 },
  57         { "record",     cmd_record,     0 },
  58         { "report",     cmd_report,     0 },
  59         { "bench",      cmd_bench,      0 },
  60         { "stat",       cmd_stat,       0 },
  61         { "timechart",  cmd_timechart,  0 },
  62         { "top",        cmd_top,        0 },
  63         { "annotate",   cmd_annotate,   0 },
  64         { "version",    cmd_version,    0 },
  65         { "script",     cmd_script,     0 },
  66         { "sched",      cmd_sched,      0 },
  67 #ifdef HAVE_LIBELF_SUPPORT
  68         { "probe",      cmd_probe,      0 },
  69 #endif
  70         { "kmem",       cmd_kmem,       0 },
  71         { "lock",       cmd_lock,       0 },
  72         { "kvm",        cmd_kvm,        0 },
  73         { "test",       cmd_test,       0 },
  74 #ifdef HAVE_LIBAUDIT_SUPPORT
  75         { "trace",      cmd_trace,      0 },
  76 #endif
  77         { "inject",     cmd_inject,     0 },
  78         { "mem",        cmd_mem,        0 },
  79         { "data",       cmd_data,       0 },
  80         { "ftrace",     cmd_ftrace,     0 },
  81 };
  82
  83 struct pager_config {
  84         const char *cmd;
  85         int val;
  86 };
  87
  88 static int pager_command_config(const char *var, const char *value, void *data)
  89 {
  90         struct pager_config *c = data;
  91         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  92                 c->val = perf_config_bool(var, value);
  93         return 0;
  94 }
  95
  96 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  97 static int check_pager_config(const char *cmd)
  98 {
  99         int err;
 100         struct pager_config c;
 101         c.cmd = cmd;
 102         c.val = -1;
 103         err = perf_config(pager_command_config, &c);
 104         return err ?: c.val;
 105 }
 106
 107 static int browser_command_config(const char *var, const char *value, void *data)
 108 {
 109         struct pager_config *c = data;
 110         if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
 111                 c->val = perf_config_bool(var, value);
 112         if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
 113                 c->val = perf_config_bool(var, value) ? 2 : 0;
 114         return 0;
 115 }
 116
 117 /*
 118  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
 119  * and -1 for "not specified"
 120  */
 121 static int check_browser_config(const char *cmd)
 122 {
 123         int err;
 124         struct pager_config c;
 125         c.cmd = cmd;
 126         c.val = -1;
 127         err = perf_config(browser_command_config, &c);
 128         return err ?: c.val;
 129 }
 130
 131 static void commit_pager_choice(void)
 132 {
 133         switch (use_pager) {
 134         case 0:
 135                 setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
 136                 break;
 137         case 1:
 138                 /* setup_pager(); */
 139                 break;
 140         default:
 141                 break;
 142         }
 143 }
 144
 145 struct option options[] = {
 146         OPT_ARGUMENT("help", "help"),
 147         OPT_ARGUMENT("version", "version"),
 148         OPT_ARGUMENT("exec-path", "exec-path"),
 149         OPT_ARGUMENT("html-path", "html-path"),
 150         OPT_ARGUMENT("paginate", "paginate"),
 151         OPT_ARGUMENT("no-pager", "no-pager"),
 152         OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
 153         OPT_ARGUMENT("buildid-dir", "buildid-dir"),
 154         OPT_ARGUMENT("list-cmds", "list-cmds"),
 155         OPT_ARGUMENT("list-opts", "list-opts"),
 156         OPT_ARGUMENT("debug", "debug"),
 157         OPT_END()
 158 };
 159
 160 static int handle_options(const char ***argv, int *argc, int *envchanged)
 161 {
 162         int handled = 0;
 163
 164         while (*argc > 0) {
 165                 const char *cmd = (*argv)[0];
 166                 if (cmd[0] != '-')
 167                         break;
 168
 169                 /*
 170                  * For legacy reasons, the "version" and "help"
 171                  * commands can be written with "--" prepended
 172                  * to make them look like flags.
 173                  */
 174                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 175                         break;
 176
 177                 /*
 178                  * Shortcut for '-h' and '-v' options to invoke help
 179                  * and version command.
 180                  */
 181                 if (!strcmp(cmd, "-h")) {
 182                         (*argv)[0] = "--help";
 183                         break;
 184                 }
 185
 186                 if (!strcmp(cmd, "-v")) {
 187                         (*argv)[0] = "--version";
 188                         break;
 189                 }
 190
 191                 /*
 192                  * Check remaining flags.
 193                  */
 194                 if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
 195                         cmd += strlen(CMD_EXEC_PATH);
 196                         if (*cmd == '=')
 197                                 set_argv_exec_path(cmd + 1);
 198                         else {
 199                                 puts(get_argv_exec_path());
 200                                 exit(0);
 201                         }
 202                 } else if (!strcmp(cmd, "--html-path")) {
 203                         puts(system_path(PERF_HTML_PATH));
 204                         exit(0);
 205                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 206                         use_pager = 1;
 207                 } else if (!strcmp(cmd, "--no-pager")) {
 208                         use_pager = 0;
 209                         if (envchanged)
 210                                 *envchanged = 1;
 211                 } else if (!strcmp(cmd, "--debugfs-dir")) {
 212                         if (*argc < 2) {
 213                                 fprintf(stderr, "No directory given for --debugfs-dir.\n");
 214                                 usage(perf_usage_string);
 215                         }
 216                         tracing_path_set((*argv)[1]);
 217                         if (envchanged)
 218                                 *envchanged = 1;
 219                         (*argv)++;
 220                         (*argc)--;
 221                 } else if (!strcmp(cmd, "--buildid-dir")) {
 222                         if (*argc < 2) {
 223                                 fprintf(stderr, "No directory given for --buildid-dir.\n");
 224                                 usage(perf_usage_string);
 225                         }
 226                         set_buildid_dir((*argv)[1]);
 227                         if (envchanged)
 228                                 *envchanged = 1;
 229                         (*argv)++;
 230                         (*argc)--;
 231                 } else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
 232                         tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
 233                         fprintf(stderr, "dir: %s\n", tracing_path);
 234                         if (envchanged)
 235                                 *envchanged = 1;
 236                 } else if (!strcmp(cmd, "--list-cmds")) {
 237                         unsigned int i;
 238
 239                         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 240                                 struct cmd_struct *p = commands+i;
 241                                 printf("%s ", p->cmd);
 242                         }
 243                         putchar('\n');
 244                         exit(0);
 245                 } else if (!strcmp(cmd, "--list-opts")) {
 246                         unsigned int i;
 247
 248                         for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
 249                                 struct option *p = options+i;
 250                                 printf("--%s ", p->long_name);
 251                         }
 252                         putchar('\n');
 253                         exit(0);
 254                 } else if (!strcmp(cmd, "--debug")) {
 255                         if (*argc < 2) {
 256                                 fprintf(stderr, "No variable specified for --debug.\n");
 257                                 usage(perf_usage_string);
 258                         }
 259                         if (perf_debug_option((*argv)[1]))
 260                                 usage(perf_usage_string);
 261
 262                         (*argv)++;
 263                         (*argc)--;
 264                 } else {
 265                         fprintf(stderr, "Unknown option: %s\n", cmd);
 266                         usage(perf_usage_string);
 267                 }
 268
 269                 (*argv)++;
 270                 (*argc)--;
 271                 handled++;
 272         }
 273         return handled;
 274 }
 275
 276 #define RUN_SETUP       (1<<0)
 277 #define USE_PAGER       (1<<1)
 278
 279 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 280 {
 281         int status;
 282         struct stat st;
 283         char sbuf[STRERR_BUFSIZE];
 284
 285         if (use_browser == -1)
 286                 use_browser = check_browser_config(p->cmd);
 287
 288         if (use_pager == -1 && p->option & RUN_SETUP)
 289                 use_pager = check_pager_config(p->cmd);
 290         if (use_pager == -1 && p->option & USE_PAGER)
 291                 use_pager = 1;
 292         commit_pager_choice();
 293
 294         perf_env__set_cmdline(&perf_env, argc, argv);
 295         status = p->fn(argc, argv);
 296         perf_config__exit();
 297         exit_browser(status);
 298         perf_env__exit(&perf_env);
 299         bpf__clear();
 300
 301         if (status)
 302                 return status & 0xff;
 303
 304         /* Somebody closed stdout? */
 305         if (fstat(fileno(stdout), &st))
 306                 return 0;
 307         /* Ignore write errors for pipes and sockets.. */
 308         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 309                 return 0;
 310
 311         status = 1;
 312         /* Check for ENOSPC and EIO errors.. */
 313         if (fflush(stdout)) {
 314                 fprintf(stderr, "write failure on standard output: %s",
 315                         str_error_r(errno, sbuf, sizeof(sbuf)));
 316                 goto out;
 317         }
 318         if (ferror(stdout)) {
 319                 fprintf(stderr, "unknown write failure on standard output");
 320                 goto out;
 321         }
 322         if (fclose(stdout)) {
 323                 fprintf(stderr, "close failed on standard output: %s",
 324                         str_error_r(errno, sbuf, sizeof(sbuf)));
 325                 goto out;
 326         }
 327         status = 0;
 328 out:
 329         return status;
 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
 337         /* Turn "perf cmd --help" into "perf help cmd" */
 338         if (argc > 1 && !strcmp(argv[1], "--help")) {
 339                 argv[1] = argv[0];
 340                 argv[0] = cmd = "help";
 341         }
 342
 343         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 344                 struct cmd_struct *p = commands+i;
 345                 if (strcmp(p->cmd, cmd))
 346                         continue;
 347                 exit(run_builtin(p, argc, argv));
 348         }
 349 }
 350
 351 static void execv_dashed_external(const char **argv)
 352 {
 353         char *cmd;
 354         const char *tmp;
 355         int status;
 356
 357         if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
 358                 goto do_die;
 359
 360         /*
 361          * argv[0] must be the perf command, but the argv array
 362          * belongs to the caller, and may be reused in
 363          * subsequent loop iterations. Save argv[0] and
 364          * restore it on error.
 365          */
 366         tmp = argv[0];
 367         argv[0] = cmd;
 368
 369         /*
 370          * if we fail because the command is not found, it is
 371          * OK to return. Otherwise, we just pass along the status code.
 372          */
 373         status = run_command_v_opt(argv, 0);
 374         if (status != -ERR_RUN_COMMAND_EXEC) {
 375                 if (IS_RUN_COMMAND_ERR(status)) {
 376 do_die:
 377                         pr_err("FATAL: unable to run '%s'", argv[0]);
 378                         status = -128;
 379                 }
 380                 exit(-status);
 381         }
 382         errno = ENOENT; /* as if we called execvp */
 383
 384         argv[0] = tmp;
 385         zfree(&cmd);
 386 }
 387
 388 static int run_argv(int *argcp, const char ***argv)
 389 {
 390         /* See if it's an internal command */
 391         handle_internal_command(*argcp, *argv);
 392
 393         /* .. then try the external ones */
 394         execv_dashed_external(*argv);
 395         return 0;
 396 }
 397
 398 static void pthread__block_sigwinch(void)
 399 {
 400         sigset_t set;
 401
 402         sigemptyset(&set);
 403         sigaddset(&set, SIGWINCH);
 404         pthread_sigmask(SIG_BLOCK, &set, NULL);
 405 }
 406
 407 void pthread__unblock_sigwinch(void)
 408 {
 409         sigset_t set;
 410
 411         sigemptyset(&set);
 412         sigaddset(&set, SIGWINCH);
 413         pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 414 }
 415
 416 #ifdef _SC_LEVEL1_DCACHE_LINESIZE
 417 #define cache_line_size(cacheline_sizep) *cacheline_sizep = sysconf(_SC_LEVEL1_DCACHE_LINESIZE)
 418 #else
 419 static void cache_line_size(int *cacheline_sizep)
 420 {
 421         if (sysfs__read_int("devices/system/cpu/cpu0/cache/index0/coherency_line_size", cacheline_sizep))
 422                 pr_debug("cannot determine cache line size");
 423 }
 424 #endif
 425
 426 int main(int argc, const char **argv)
 427 {
 428         int err;
 429         const char *cmd;
 430         char sbuf[STRERR_BUFSIZE];
 431         int value;
 432
 433         /* libsubcmd init */
 434         exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
 435         pager_init(PERF_PAGER_ENVIRONMENT);
 436
 437         /* The page_size is placed in util object. */
 438         page_size = sysconf(_SC_PAGE_SIZE);
 439         cache_line_size(&cacheline_size);
 440
 441         if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
 442                 sysctl_perf_event_max_stack = value;
 443
 444         if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
 445                 sysctl_perf_event_max_contexts_per_stack = value;
 446
 447         cmd = extract_argv0_path(argv[0]);
 448         if (!cmd)
 449                 cmd = "perf-help";
 450
 451         srandom(time(NULL));
 452
 453         perf_config__init();
 454         err = perf_config(perf_default_config, NULL);
 455         if (err)
 456                 return err;
 457         set_buildid_dir(NULL);
 458
 459         /* get debugfs/tracefs mount point from /proc/mounts */
 460         tracing_path_mount();
 461
 462         /*
 463          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
 464          *
 465          *  - cannot take flags in between the "perf" and the "xxxx".
 466          *  - cannot execute it externally (since it would just do
 467          *    the same thing over again)
 468          *
 469          * So we just directly call the internal command handler, and
 470          * die if that one cannot handle it.
 471          */
 472         if (!prefixcmp(cmd, "perf-")) {
 473                 cmd += 5;
 474                 argv[0] = cmd;
 475                 handle_internal_command(argc, argv);
 476                 fprintf(stderr, "cannot handle %s internally", cmd);
 477                 goto out;
 478         }
 479         if (!prefixcmp(cmd, "trace")) {
 480 #ifdef HAVE_LIBAUDIT_SUPPORT
 481                 setup_path();
 482                 argv[0] = "trace";
 483                 return cmd_trace(argc, argv);
 484 #else
 485                 fprintf(stderr,
 486                         "trace command not available: missing audit-libs devel package at build time.\n");
 487                 goto out;
 488 #endif
 489         }
 490         /* Look for flags.. */
 491         argv++;
 492         argc--;
 493         handle_options(&argv, &argc, NULL);
 494         commit_pager_choice();
 495
 496         if (argc > 0) {
 497                 if (!prefixcmp(argv[0], "--"))
 498                         argv[0] += 2;
 499         } else {
 500                 /* The user didn't specify a command; give them help */
 501                 printf("\n usage: %s\n\n", perf_usage_string);
 502                 list_common_cmds_help();
 503                 printf("\n %s\n\n", perf_more_info_string);
 504                 goto out;
 505         }
 506         cmd = argv[0];
 507
 508         test_attr__init();
 509
 510         /*
 511          * We use PATH to find perf commands, but we prepend some higher
 512          * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
 513          * environment, and the $(perfexecdir) from the Makefile at build
 514          * time.
 515          */
 516         setup_path();
 517         /*
 518          * Block SIGWINCH notifications so that the thread that wants it can
 519          * unblock and get syscalls like select interrupted instead of waiting
 520          * forever while the signal goes to some other non interested thread.
 521          */
 522         pthread__block_sigwinch();
 523
 524         perf_debug_setup();
 525
 526         while (1) {
 527                 static int done_help;
 528
 529                 run_argv(&argc, &argv);
 530
 531                 if (errno != ENOENT)
 532                         break;
 533
 534                 if (!done_help) {
 535                         cmd = argv[0] = help_unknown_cmd(cmd);
 536                         done_help = 1;
 537                 } else
 538                         break;
 539         }
 540
 541         fprintf(stderr, "Failed to run command '%s': %s\n",
 542                 cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
 543 out:
 544         return 1;
 545 }