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