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__set_cmdline(&perf_env, argc, argv);
 302         status = p->fn(argc, argv);
 303         perf_config__exit();
 304         exit_browser(status);
 305         perf_env__exit(&perf_env);
 306         bpf__clear();
 307
 308         if (status)
 309                 return status & 0xff;
 310
 311         /* Somebody closed stdout? */
 312         if (fstat(fileno(stdout), &st))
 313                 return 0;
 314         /* Ignore write errors for pipes and sockets.. */
 315         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 316                 return 0;
 317
 318         status = 1;
 319         /* Check for ENOSPC and EIO errors.. */
 320         if (fflush(stdout)) {
 321                 fprintf(stderr, "write failure on standard output: %s",
 322                         str_error_r(errno, sbuf, sizeof(sbuf)));
 323                 goto out;
 324         }
 325         if (ferror(stdout)) {
 326                 fprintf(stderr, "unknown write failure on standard output");
 327                 goto out;
 328         }
 329         if (fclose(stdout)) {
 330                 fprintf(stderr, "close failed on standard output: %s",
 331                         str_error_r(errno, sbuf, sizeof(sbuf)));
 332                 goto out;
 333         }
 334         status = 0;
 335 out:
 336         return status;
 337 }
 338
 339 static void handle_internal_command(int argc, const char **argv)
 340 {
 341         const char *cmd = argv[0];
 342         unsigned int i;
 343
 344         /* Turn "perf cmd --help" into "perf help cmd" */
 345         if (argc > 1 && !strcmp(argv[1], "--help")) {
 346                 argv[1] = argv[0];
 347                 argv[0] = cmd = "help";
 348         }
 349
 350         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 351                 struct cmd_struct *p = commands+i;
 352                 if (strcmp(p->cmd, cmd))
 353                         continue;
 354                 exit(run_builtin(p, argc, argv));
 355         }
 356 }
 357
 358 static void execv_dashed_external(const char **argv)
 359 {
 360         char *cmd;
 361         const char *tmp;
 362         int status;
 363
 364         if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
 365                 goto do_die;
 366
 367         /*
 368          * argv[0] must be the perf command, but the argv array
 369          * belongs to the caller, and may be reused in
 370          * subsequent loop iterations. Save argv[0] and
 371          * restore it on error.
 372          */
 373         tmp = argv[0];
 374         argv[0] = cmd;
 375
 376         /*
 377          * if we fail because the command is not found, it is
 378          * OK to return. Otherwise, we just pass along the status code.
 379          */
 380         status = run_command_v_opt(argv, 0);
 381         if (status != -ERR_RUN_COMMAND_EXEC) {
 382                 if (IS_RUN_COMMAND_ERR(status)) {
 383 do_die:
 384                         pr_err("FATAL: unable to run '%s'", argv[0]);
 385                         status = -128;
 386                 }
 387                 exit(-status);
 388         }
 389         errno = ENOENT; /* as if we called execvp */
 390
 391         argv[0] = tmp;
 392         zfree(&cmd);
 393 }
 394
 395 static int run_argv(int *argcp, const char ***argv)
 396 {
 397         /* See if it's an internal command */
 398         handle_internal_command(*argcp, *argv);
 399
 400         /* .. then try the external ones */
 401         execv_dashed_external(*argv);
 402         return 0;
 403 }
 404
 405 static void pthread__block_sigwinch(void)
 406 {
 407         sigset_t set;
 408
 409         sigemptyset(&set);
 410         sigaddset(&set, SIGWINCH);
 411         pthread_sigmask(SIG_BLOCK, &set, NULL);
 412 }
 413
 414 void pthread__unblock_sigwinch(void)
 415 {
 416         sigset_t set;
 417
 418         sigemptyset(&set);
 419         sigaddset(&set, SIGWINCH);
 420         pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 421 }
 422
 423 int main(int argc, const char **argv)
 424 {
 425         int err;
 426         const char *cmd;
 427         char sbuf[STRERR_BUFSIZE];
 428
 429         /* libsubcmd init */
 430         exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
 431         pager_init(PERF_PAGER_ENVIRONMENT);
 432
 433         /* The page_size is placed in util object. */
 434         page_size = sysconf(_SC_PAGE_SIZE);
 435
 436         cmd = extract_argv0_path(argv[0]);
 437         if (!cmd)
 438                 cmd = "perf-help";
 439
 440         srandom(time(NULL));
 441
 442         /* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
 443         config_exclusive_filename = getenv("PERF_CONFIG");
 444
 445         err = perf_config(perf_default_config, NULL);
 446         if (err)
 447                 return err;
 448         set_buildid_dir(NULL);
 449
 450         /*
 451          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
 452          *
 453          *  - cannot take flags in between the "perf" and the "xxxx".
 454          *  - cannot execute it externally (since it would just do
 455          *    the same thing over again)
 456          *
 457          * So we just directly call the internal command handler. If that one
 458          * fails to handle this, then maybe we just run a renamed perf binary
 459          * that contains a dash in its name. To handle this scenario, we just
 460          * fall through and ignore the "xxxx" part of the command string.
 461          */
 462         if (strstarts(cmd, "perf-")) {
 463                 cmd += 5;
 464                 argv[0] = cmd;
 465                 handle_internal_command(argc, argv);
 466                 /*
 467                  * If the command is handled, the above function does not
 468                  * return undo changes and fall through in such a case.
 469                  */
 470                 cmd -= 5;
 471                 argv[0] = cmd;
 472         }
 473         if (strstarts(cmd, "trace")) {
 474 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
 475                 setup_path();
 476                 argv[0] = "trace";
 477                 return cmd_trace(argc, argv);
 478 #else
 479                 fprintf(stderr,
 480                         "trace command not available: missing audit-libs devel package at build time.\n");
 481                 goto out;
 482 #endif
 483         }
 484         /* Look for flags.. */
 485         argv++;
 486         argc--;
 487         handle_options(&argv, &argc, NULL);
 488         commit_pager_choice();
 489
 490         if (argc > 0) {
 491                 if (strstarts(argv[0], "--"))
 492                         argv[0] += 2;
 493         } else {
 494                 /* The user didn't specify a command; give them help */
 495                 printf("\n usage: %s\n\n", perf_usage_string);
 496                 list_common_cmds_help();
 497                 printf("\n %s\n\n", perf_more_info_string);
 498                 goto out;
 499         }
 500         cmd = argv[0];
 501
 502         test_attr__init();
 503
 504         /*
 505          * We use PATH to find perf commands, but we prepend some higher
 506          * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
 507          * environment, and the $(perfexecdir) from the Makefile at build
 508          * time.
 509          */
 510         setup_path();
 511         /*
 512          * Block SIGWINCH notifications so that the thread that wants it can
 513          * unblock and get syscalls like select interrupted instead of waiting
 514          * forever while the signal goes to some other non interested thread.
 515          */
 516         pthread__block_sigwinch();
 517
 518         perf_debug_setup();
 519
 520         while (1) {
 521                 static int done_help;
 522
 523                 run_argv(&argc, &argv);
 524
 525                 if (errno != ENOENT)
 526                         break;
 527
 528                 if (!done_help) {
 529                         cmd = argv[0] = help_unknown_cmd(cmd);
 530                         done_help = 1;
 531                 } else
 532                         break;
 533         }
 534
 535         fprintf(stderr, "Failed to run command '%s': %s\n",
 536                 cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
 537 out:
 538         return 1;
 539 }