tools/perf/perf.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * perf.c
   4  *
   5  * Performance analysis utility.
   6  *
   7  * This is the main hub from which the sub-commands (perf stat,
   8  * perf top, perf record, perf report, etc.) are started.
   9  */
  10 #include "builtin.h"
  11
  12 #include "util/env.h"
  13 #include <subcmd/exec-cmd.h>
  14 #include "util/config.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 "util/event.h"
  21 #include <api/fs/fs.h>
  22 #include <api/fs/tracing_path.h>
  23 #include <errno.h>
  24 #include <pthread.h>
  25 #include <signal.h>
  26 #include <stdlib.h>
  27 #include <time.h>
  28 #include <sys/types.h>
  29 #include <sys/stat.h>
  30 #include <unistd.h>
  31 #include <linux/kernel.h>
  32
  33 const char perf_usage_string[] =
  34         "perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
  35
  36 const char perf_more_info_string[] =
  37         "See 'perf help COMMAND' for more information on a specific command.";
  38
  39 static int use_pager = -1;
  40 const char *input_name;
  41
  42 struct cmd_struct {
  43         const char *cmd;
  44         int (*fn)(int, const char **);
  45         int option;
  46 };
  47
  48 static struct cmd_struct commands[] = {
  49         { "buildid-cache", cmd_buildid_cache, 0 },
  50         { "buildid-list", cmd_buildid_list, 0 },
  51         { "config",     cmd_config,     0 },
  52         { "c2c",        cmd_c2c,        0 },
  53         { "diff",       cmd_diff,       0 },
  54         { "evlist",     cmd_evlist,     0 },
  55         { "help",       cmd_help,       0 },
  56         { "kallsyms",   cmd_kallsyms,   0 },
  57         { "list",       cmd_list,       0 },
  58         { "record",     cmd_record,     0 },
  59         { "report",     cmd_report,     0 },
  60         { "bench",      cmd_bench,      0 },
  61         { "stat",       cmd_stat,       0 },
  62         { "timechart",  cmd_timechart,  0 },
  63         { "top",        cmd_top,        0 },
  64         { "annotate",   cmd_annotate,   0 },
  65         { "version",    cmd_version,    0 },
  66         { "script",     cmd_script,     0 },
  67         { "sched",      cmd_sched,      0 },
  68 #ifdef HAVE_LIBELF_SUPPORT
  69         { "probe",      cmd_probe,      0 },
  70 #endif
  71         { "kmem",       cmd_kmem,       0 },
  72         { "lock",       cmd_lock,       0 },
  73         { "kvm",        cmd_kvm,        0 },
  74         { "test",       cmd_test,       0 },
  75 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
  76         { "trace",      cmd_trace,      0 },
  77 #endif
  78         { "inject",     cmd_inject,     0 },
  79         { "mem",        cmd_mem,        0 },
  80         { "data",       cmd_data,       0 },
  81         { "ftrace",     cmd_ftrace,     0 },
  82 };
  83
  84 struct pager_config {
  85         const char *cmd;
  86         int val;
  87 };
  88
  89 static int pager_command_config(const char *var, const char *value, void *data)
  90 {
  91         struct pager_config *c = data;
  92         if (strstarts(var, "pager.") && !strcmp(var + 6, c->cmd))
  93                 c->val = perf_config_bool(var, value);
  94         return 0;
  95 }
  96
  97 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  98 static int check_pager_config(const char *cmd)
  99 {
 100         int err;
 101         struct pager_config c;
 102         c.cmd = cmd;
 103         c.val = -1;
 104         err = perf_config(pager_command_config, &c);
 105         return err ?: c.val;
 106 }
 107
 108 static int browser_command_config(const char *var, const char *value, void *data)
 109 {
 110         struct pager_config *c = data;
 111         if (strstarts(var, "tui.") && !strcmp(var + 4, c->cmd))
 112                 c->val = perf_config_bool(var, value);
 113         if (strstarts(var, "gtk.") && !strcmp(var + 4, c->cmd))
 114                 c->val = perf_config_bool(var, value) ? 2 : 0;
 115         return 0;
 116 }
 117
 118 /*
 119  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
 120  * and -1 for "not specified"
 121  */
 122 static int check_browser_config(const char *cmd)
 123 {
 124         int err;
 125         struct pager_config c;
 126         c.cmd = cmd;
 127         c.val = -1;
 128         err = perf_config(browser_command_config, &c);
 129         return err ?: c.val;
 130 }
 131
 132 static void commit_pager_choice(void)
 133 {
 134         switch (use_pager) {
 135         case 0:
 136                 setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
 137                 break;
 138         case 1:
 139                 /* setup_pager(); */
 140                 break;
 141         default:
 142                 break;
 143         }
 144 }
 145
 146 struct option options[] = {
 147         OPT_ARGUMENT("help", "help"),
 148         OPT_ARGUMENT("version", "version"),
 149         OPT_ARGUMENT("exec-path", "exec-path"),
 150         OPT_ARGUMENT("html-path", "html-path"),
 151         OPT_ARGUMENT("paginate", "paginate"),
 152         OPT_ARGUMENT("no-pager", "no-pager"),
 153         OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
 154         OPT_ARGUMENT("buildid-dir", "buildid-dir"),
 155         OPT_ARGUMENT("list-cmds", "list-cmds"),
 156         OPT_ARGUMENT("list-opts", "list-opts"),
 157         OPT_ARGUMENT("debug", "debug"),
 158         OPT_END()
 159 };
 160
 161 static int handle_options(const char ***argv, int *argc, int *envchanged)
 162 {
 163         int handled = 0;
 164
 165         while (*argc > 0) {
 166                 const char *cmd = (*argv)[0];
 167                 if (cmd[0] != '-')
 168                         break;
 169
 170                 /*
 171                  * For legacy reasons, the "version" and "help"
 172                  * commands can be written with "--" prepended
 173                  * to make them look like flags.
 174                  */
 175                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 176                         break;
 177
 178                 /*
 179                  * Shortcut for '-h' and '-v' options to invoke help
 180                  * and version command.
 181                  */
 182                 if (!strcmp(cmd, "-h")) {
 183                         (*argv)[0] = "--help";
 184                         break;
 185                 }
 186
 187                 if (!strcmp(cmd, "-v")) {
 188                         (*argv)[0] = "--version";
 189                         break;
 190                 }
 191
 192                 if (!strcmp(cmd, "-vv")) {
 193                         (*argv)[0] = "version";
 194                         version_verbose = 1;
 195                         break;
 196                 }
 197
 198                 /*
 199                  * Check remaining flags.
 200                  */
 201                 if (strstarts(cmd, CMD_EXEC_PATH)) {
 202                         cmd += strlen(CMD_EXEC_PATH);
 203                         if (*cmd == '=')
 204                                 set_argv_exec_path(cmd + 1);
 205                         else {
 206                                 puts(get_argv_exec_path());
 207                                 exit(0);
 208                         }
 209                 } else if (!strcmp(cmd, "--html-path")) {
 210                         puts(system_path(PERF_HTML_PATH));
 211                         exit(0);
 212                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 213                         use_pager = 1;
 214                 } else if (!strcmp(cmd, "--no-pager")) {
 215                         use_pager = 0;
 216                         if (envchanged)
 217                                 *envchanged = 1;
 218                 } else if (!strcmp(cmd, "--debugfs-dir")) {
 219                         if (*argc < 2) {
 220                                 fprintf(stderr, "No directory given for --debugfs-dir.\n");
 221                                 usage(perf_usage_string);
 222                         }
 223                         tracing_path_set((*argv)[1]);
 224                         if (envchanged)
 225                                 *envchanged = 1;
 226                         (*argv)++;
 227                         (*argc)--;
 228                 } else if (!strcmp(cmd, "--buildid-dir")) {
 229                         if (*argc < 2) {
 230                                 fprintf(stderr, "No directory given for --buildid-dir.\n");
 231                                 usage(perf_usage_string);
 232                         }
 233                         set_buildid_dir((*argv)[1]);
 234                         if (envchanged)
 235                                 *envchanged = 1;
 236                         (*argv)++;
 237                         (*argc)--;
 238                 } else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
 239                         tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
 240                         fprintf(stderr, "dir: %s\n", tracing_path_mount());
 241                         if (envchanged)
 242                                 *envchanged = 1;
 243                 } else if (!strcmp(cmd, "--list-cmds")) {
 244                         unsigned int i;
 245
 246                         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 247                                 struct cmd_struct *p = commands+i;
 248                                 printf("%s ", p->cmd);
 249                         }
 250                         putchar('\n');
 251                         exit(0);
 252                 } else if (!strcmp(cmd, "--list-opts")) {
 253                         unsigned int i;
 254
 255                         for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
 256                                 struct option *p = options+i;
 257                                 printf("--%s ", p->long_name);
 258                         }
 259                         putchar('\n');
 260                         exit(0);
 261                 } else if (!strcmp(cmd, "--debug")) {
 262                         if (*argc < 2) {
 263                                 fprintf(stderr, "No variable specified for --debug.\n");
 264                                 usage(perf_usage_string);
 265                         }
 266                         if (perf_debug_option((*argv)[1]))
 267                                 usage(perf_usage_string);
 268
 269                         (*argv)++;
 270                         (*argc)--;
 271                 } else {
 272                         fprintf(stderr, "Unknown option: %s\n", cmd);
 273                         usage(perf_usage_string);
 274                 }
 275
 276                 (*argv)++;
 277                 (*argc)--;
 278                 handled++;
 279         }
 280         return handled;
 281 }
 282
 283 #define RUN_SETUP       (1<<0)
 284 #define USE_PAGER       (1<<1)
 285
 286 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 287 {
 288         int status;
 289         struct stat st;
 290         char sbuf[STRERR_BUFSIZE];
 291
 292         if (use_browser == -1)
 293                 use_browser = check_browser_config(p->cmd);
 294
 295         if (use_pager == -1 && p->option & RUN_SETUP)
 296                 use_pager = check_pager_config(p->cmd);
 297         if (use_pager == -1 && p->option & USE_PAGER)
 298                 use_pager = 1;
 299         commit_pager_choice();
 300
 301         perf_env__init(&perf_env);
 302         perf_env__set_cmdline(&perf_env, argc, argv);
 303         status = p->fn(argc, argv);
 304         perf_config__exit();
 305         exit_browser(status);
 306         perf_env__exit(&perf_env);
 307         bpf__clear();
 308
 309         if (status)
 310                 return status & 0xff;
 311
 312         /* Somebody closed stdout? */
 313         if (fstat(fileno(stdout), &st))
 314                 return 0;
 315         /* Ignore write errors for pipes and sockets.. */
 316         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 317                 return 0;
 318
 319         status = 1;
 320         /* Check for ENOSPC and EIO errors.. */
 321         if (fflush(stdout)) {
 322                 fprintf(stderr, "write failure on standard output: %s",
 323                         str_error_r(errno, sbuf, sizeof(sbuf)));
 324                 goto out;
 325         }
 326         if (ferror(stdout)) {
 327                 fprintf(stderr, "unknown write failure on standard output");
 328                 goto out;
 329         }
 330         if (fclose(stdout)) {
 331                 fprintf(stderr, "close failed on standard output: %s",
 332                         str_error_r(errno, sbuf, sizeof(sbuf)));
 333                 goto out;
 334         }
 335         status = 0;
 336 out:
 337         return status;
 338 }
 339
 340 static void handle_internal_command(int argc, const char **argv)
 341 {
 342         const char *cmd = argv[0];
 343         unsigned int i;
 344
 345         /* Turn "perf cmd --help" into "perf help cmd" */
 346         if (argc > 1 && !strcmp(argv[1], "--help")) {
 347                 argv[1] = argv[0];
 348                 argv[0] = cmd = "help";
 349         }
 350
 351         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 352                 struct cmd_struct *p = commands+i;
 353                 if (strcmp(p->cmd, cmd))
 354                         continue;
 355                 exit(run_builtin(p, argc, argv));
 356         }
 357 }
 358
 359 static void execv_dashed_external(const char **argv)
 360 {
 361         char *cmd;
 362         const char *tmp;
 363         int status;
 364
 365         if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
 366                 goto do_die;
 367
 368         /*
 369          * argv[0] must be the perf command, but the argv array
 370          * belongs to the caller, and may be reused in
 371          * subsequent loop iterations. Save argv[0] and
 372          * restore it on error.
 373          */
 374         tmp = argv[0];
 375         argv[0] = cmd;
 376
 377         /*
 378          * if we fail because the command is not found, it is
 379          * OK to return. Otherwise, we just pass along the status code.
 380          */
 381         status = run_command_v_opt(argv, 0);
 382         if (status != -ERR_RUN_COMMAND_EXEC) {
 383                 if (IS_RUN_COMMAND_ERR(status)) {
 384 do_die:
 385                         pr_err("FATAL: unable to run '%s'", argv[0]);
 386                         status = -128;
 387                 }
 388                 exit(-status);
 389         }
 390         errno = ENOENT; /* as if we called execvp */
 391
 392         argv[0] = tmp;
 393         zfree(&cmd);
 394 }
 395
 396 static int run_argv(int *argcp, const char ***argv)
 397 {
 398         /* See if it's an internal command */
 399         handle_internal_command(*argcp, *argv);
 400
 401         /* .. then try the external ones */
 402         execv_dashed_external(*argv);
 403         return 0;
 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         int err;
 427         const char *cmd;
 428         char sbuf[STRERR_BUFSIZE];
 429
 430         /* libsubcmd init */
 431         exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
 432         pager_init(PERF_PAGER_ENVIRONMENT);
 433
 434         /* The page_size is placed in util object. */
 435         page_size = sysconf(_SC_PAGE_SIZE);
 436
 437         cmd = extract_argv0_path(argv[0]);
 438         if (!cmd)
 439                 cmd = "perf-help";
 440
 441         srandom(time(NULL));
 442
 443         err = perf_config(perf_default_config, NULL);
 444         if (err)
 445                 return err;
 446         set_buildid_dir(NULL);
 447
 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. If that one
 456          * fails to handle this, then maybe we just run a renamed perf binary
 457          * that contains a dash in its name. To handle this scenario, we just
 458          * fall through and ignore the "xxxx" part of the command string.
 459          */
 460         if (strstarts(cmd, "perf-")) {
 461                 cmd += 5;
 462                 argv[0] = cmd;
 463                 handle_internal_command(argc, argv);
 464                 /*
 465                  * If the command is handled, the above function does not
 466                  * return undo changes and fall through in such a case.
 467                  */
 468                 cmd -= 5;
 469                 argv[0] = cmd;
 470         }
 471         if (strstarts(cmd, "trace")) {
 472 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
 473                 setup_path();
 474                 argv[0] = "trace";
 475                 return cmd_trace(argc, argv);
 476 #else
 477                 fprintf(stderr,
 478                         "trace command not available: missing audit-libs devel package at build time.\n");
 479                 goto out;
 480 #endif
 481         }
 482         /* Look for flags.. */
 483         argv++;
 484         argc--;
 485         handle_options(&argv, &argc, NULL);
 486         commit_pager_choice();
 487
 488         if (argc > 0) {
 489                 if (strstarts(argv[0], "--"))
 490                         argv[0] += 2;
 491         } else {
 492                 /* The user didn't specify a command; give them help */
 493                 printf("\n usage: %s\n\n", perf_usage_string);
 494                 list_common_cmds_help();
 495                 printf("\n %s\n\n", perf_more_info_string);
 496                 goto out;
 497         }
 498         cmd = argv[0];
 499
 500         test_attr__init();
 501
 502         /*
 503          * We use PATH to find perf commands, but we prepend some higher
 504          * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
 505          * environment, and the $(perfexecdir) from the Makefile at build
 506          * time.
 507          */
 508         setup_path();
 509         /*
 510          * Block SIGWINCH notifications so that the thread that wants it can
 511          * unblock and get syscalls like select interrupted instead of waiting
 512          * forever while the signal goes to some other non interested thread.
 513          */
 514         pthread__block_sigwinch();
 515
 516         perf_debug_setup();
 517
 518         while (1) {
 519                 static int done_help;
 520
 521                 run_argv(&argc, &argv);
 522
 523                 if (errno != ENOENT)
 524                         break;
 525
 526                 if (!done_help) {
 527                         cmd = argv[0] = help_unknown_cmd(cmd);
 528                         done_help = 1;
 529                 } else
 530                         break;
 531         }
 532
 533         fprintf(stderr, "Failed to run command '%s': %s\n",
 534                 cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
 535 out:
 536         return 1;
 537 }