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/string.h" 17 #include "util/debugfs.h" 18 19 const char perf_usage_string[] = 20 "perf [--version] [--help] COMMAND [ARGS]"; 21 22 const char perf_more_info_string[] = 23 "See 'perf help COMMAND' for more information on a specific command."; 24 25 static int use_pager = -1; 26 struct pager_config { 27 const char *cmd; 28 int val; 29 }; 30 31 static char debugfs_mntpt[MAXPATHLEN]; 32 33 static int pager_command_config(const char *var, const char *value, void *data) 34 { 35 struct pager_config *c = data; 36 if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd)) 37 c->val = perf_config_bool(var, value); 38 return 0; 39 } 40 41 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */ 42 int check_pager_config(const char *cmd) 43 { 44 struct pager_config c; 45 c.cmd = cmd; 46 c.val = -1; 47 perf_config(pager_command_config, &c); 48 return c.val; 49 } 50 51 static void commit_pager_choice(void) 52 { 53 switch (use_pager) { 54 case 0: 55 setenv("PERF_PAGER", "cat", 1); 56 break; 57 case 1: 58 /* setup_pager(); */ 59 break; 60 default: 61 break; 62 } 63 } 64 65 static void set_debugfs_path(void) 66 { 67 char *path; 68 69 path = getenv(PERF_DEBUGFS_ENVIRONMENT); 70 snprintf(debugfs_path, MAXPATHLEN, "%s/%s", path ?: debugfs_mntpt, 71 "tracing/events"); 72 } 73 74 static int handle_options(const char ***argv, int *argc, int *envchanged) 75 { 76 int handled = 0; 77 78 while (*argc > 0) { 79 const char *cmd = (*argv)[0]; 80 if (cmd[0] != '-') 81 break; 82 83 /* 84 * For legacy reasons, the "version" and "help" 85 * commands can be written with "--" prepended 86 * to make them look like flags. 87 */ 88 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version")) 89 break; 90 91 /* 92 * Check remaining flags. 93 */ 94 if (!prefixcmp(cmd, CMD_EXEC_PATH)) { 95 cmd += strlen(CMD_EXEC_PATH); 96 if (*cmd == '=') 97 perf_set_argv_exec_path(cmd + 1); 98 else { 99 puts(perf_exec_path()); 100 exit(0); 101 } 102 } else if (!strcmp(cmd, "--html-path")) { 103 puts(system_path(PERF_HTML_PATH)); 104 exit(0); 105 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) { 106 use_pager = 1; 107 } else if (!strcmp(cmd, "--no-pager")) { 108 use_pager = 0; 109 if (envchanged) 110 *envchanged = 1; 111 } else if (!strcmp(cmd, "--perf-dir")) { 112 if (*argc < 2) { 113 fprintf(stderr, "No directory given for --perf-dir.\n"); 114 usage(perf_usage_string); 115 } 116 setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1); 117 if (envchanged) 118 *envchanged = 1; 119 (*argv)++; 120 (*argc)--; 121 handled++; 122 } else if (!prefixcmp(cmd, CMD_PERF_DIR)) { 123 setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1); 124 if (envchanged) 125 *envchanged = 1; 126 } else if (!strcmp(cmd, "--work-tree")) { 127 if (*argc < 2) { 128 fprintf(stderr, "No directory given for --work-tree.\n"); 129 usage(perf_usage_string); 130 } 131 setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1); 132 if (envchanged) 133 *envchanged = 1; 134 (*argv)++; 135 (*argc)--; 136 } else if (!prefixcmp(cmd, CMD_WORK_TREE)) { 137 setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1); 138 if (envchanged) 139 *envchanged = 1; 140 } else if (!strcmp(cmd, "--debugfs-dir")) { 141 if (*argc < 2) { 142 fprintf(stderr, "No directory given for --debugfs-dir.\n"); 143 usage(perf_usage_string); 144 } 145 strncpy(debugfs_mntpt, (*argv)[1], MAXPATHLEN); 146 debugfs_mntpt[MAXPATHLEN - 1] = '\0'; 147 if (envchanged) 148 *envchanged = 1; 149 (*argv)++; 150 (*argc)--; 151 } else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) { 152 strncpy(debugfs_mntpt, cmd + strlen(CMD_DEBUGFS_DIR), MAXPATHLEN); 153 debugfs_mntpt[MAXPATHLEN - 1] = '\0'; 154 if (envchanged) 155 *envchanged = 1; 156 } else { 157 fprintf(stderr, "Unknown option: %s\n", cmd); 158 usage(perf_usage_string); 159 } 160 161 (*argv)++; 162 (*argc)--; 163 handled++; 164 } 165 return handled; 166 } 167 168 static int handle_alias(int *argcp, const char ***argv) 169 { 170 int envchanged = 0, ret = 0, saved_errno = errno; 171 int count, option_count; 172 const char **new_argv; 173 const char *alias_command; 174 char *alias_string; 175 176 alias_command = (*argv)[0]; 177 alias_string = alias_lookup(alias_command); 178 if (alias_string) { 179 if (alias_string[0] == '!') { 180 if (*argcp > 1) { 181 struct strbuf buf; 182 183 strbuf_init(&buf, PATH_MAX); 184 strbuf_addstr(&buf, alias_string); 185 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX); 186 free(alias_string); 187 alias_string = buf.buf; 188 } 189 ret = system(alias_string + 1); 190 if (ret >= 0 && WIFEXITED(ret) && 191 WEXITSTATUS(ret) != 127) 192 exit(WEXITSTATUS(ret)); 193 die("Failed to run '%s' when expanding alias '%s'", 194 alias_string + 1, alias_command); 195 } 196 count = split_cmdline(alias_string, &new_argv); 197 if (count < 0) 198 die("Bad alias.%s string", alias_command); 199 option_count = handle_options(&new_argv, &count, &envchanged); 200 if (envchanged) 201 die("alias '%s' changes environment variables\n" 202 "You can use '!perf' in the alias to do this.", 203 alias_command); 204 memmove(new_argv - option_count, new_argv, 205 count * sizeof(char *)); 206 new_argv -= option_count; 207 208 if (count < 1) 209 die("empty alias for %s", alias_command); 210 211 if (!strcmp(alias_command, new_argv[0])) 212 die("recursive alias: %s", alias_command); 213 214 new_argv = realloc(new_argv, sizeof(char *) * 215 (count + *argcp + 1)); 216 /* insert after command name */ 217 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp); 218 new_argv[count + *argcp] = NULL; 219 220 *argv = new_argv; 221 *argcp += count - 1; 222 223 ret = 1; 224 } 225 226 errno = saved_errno; 227 228 return ret; 229 } 230 231 const char perf_version_string[] = PERF_VERSION; 232 233 #define RUN_SETUP (1<<0) 234 #define USE_PAGER (1<<1) 235 /* 236 * require working tree to be present -- anything uses this needs 237 * RUN_SETUP for reading from the configuration file. 238 */ 239 #define NEED_WORK_TREE (1<<2) 240 241 struct cmd_struct { 242 const char *cmd; 243 int (*fn)(int, const char **, const char *); 244 int option; 245 }; 246 247 static int run_builtin(struct cmd_struct *p, int argc, const char **argv) 248 { 249 int status; 250 struct stat st; 251 const char *prefix; 252 253 prefix = NULL; 254 if (p->option & RUN_SETUP) 255 prefix = NULL; /* setup_perf_directory(); */ 256 257 if (use_pager == -1 && p->option & RUN_SETUP) 258 use_pager = check_pager_config(p->cmd); 259 if (use_pager == -1 && p->option & USE_PAGER) 260 use_pager = 1; 261 commit_pager_choice(); 262 set_debugfs_path(); 263 264 status = p->fn(argc, argv, prefix); 265 if (status) 266 return status & 0xff; 267 268 /* Somebody closed stdout? */ 269 if (fstat(fileno(stdout), &st)) 270 return 0; 271 /* Ignore write errors for pipes and sockets.. */ 272 if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode)) 273 return 0; 274 275 /* Check for ENOSPC and EIO errors.. */ 276 if (fflush(stdout)) 277 die("write failure on standard output: %s", strerror(errno)); 278 if (ferror(stdout)) 279 die("unknown write failure on standard output"); 280 if (fclose(stdout)) 281 die("close failed on standard output: %s", strerror(errno)); 282 return 0; 283 } 284 285 static void handle_internal_command(int argc, const char **argv) 286 { 287 const char *cmd = argv[0]; 288 static struct cmd_struct commands[] = { 289 { "buildid-cache", cmd_buildid_cache, 0 }, 290 { "buildid-list", cmd_buildid_list, 0 }, 291 { "diff", cmd_diff, 0 }, 292 { "help", cmd_help, 0 }, 293 { "list", cmd_list, 0 }, 294 { "record", cmd_record, 0 }, 295 { "report", cmd_report, 0 }, 296 { "bench", cmd_bench, 0 }, 297 { "stat", cmd_stat, 0 }, 298 { "timechart", cmd_timechart, 0 }, 299 { "top", cmd_top, 0 }, 300 { "annotate", cmd_annotate, 0 }, 301 { "version", cmd_version, 0 }, 302 { "trace", cmd_trace, 0 }, 303 { "sched", cmd_sched, 0 }, 304 { "probe", cmd_probe, 0 }, 305 { "kmem", cmd_kmem, 0 }, 306 { "lock", cmd_lock, 0 }, 307 }; 308 unsigned int i; 309 static const char ext[] = STRIP_EXTENSION; 310 311 if (sizeof(ext) > 1) { 312 i = strlen(argv[0]) - strlen(ext); 313 if (i > 0 && !strcmp(argv[0] + i, ext)) { 314 char *argv0 = strdup(argv[0]); 315 argv[0] = cmd = argv0; 316 argv0[i] = '\0'; 317 } 318 } 319 320 /* Turn "perf cmd --help" into "perf help cmd" */ 321 if (argc > 1 && !strcmp(argv[1], "--help")) { 322 argv[1] = argv[0]; 323 argv[0] = cmd = "help"; 324 } 325 326 for (i = 0; i < ARRAY_SIZE(commands); i++) { 327 struct cmd_struct *p = commands+i; 328 if (strcmp(p->cmd, cmd)) 329 continue; 330 exit(run_builtin(p, argc, argv)); 331 } 332 } 333 334 static void execv_dashed_external(const char **argv) 335 { 336 struct strbuf cmd = STRBUF_INIT; 337 const char *tmp; 338 int status; 339 340 strbuf_addf(&cmd, "perf-%s", argv[0]); 341 342 /* 343 * argv[0] must be the perf command, but the argv array 344 * belongs to the caller, and may be reused in 345 * subsequent loop iterations. Save argv[0] and 346 * restore it on error. 347 */ 348 tmp = argv[0]; 349 argv[0] = cmd.buf; 350 351 /* 352 * if we fail because the command is not found, it is 353 * OK to return. Otherwise, we just pass along the status code. 354 */ 355 status = run_command_v_opt(argv, 0); 356 if (status != -ERR_RUN_COMMAND_EXEC) { 357 if (IS_RUN_COMMAND_ERR(status)) 358 die("unable to run '%s'", argv[0]); 359 exit(-status); 360 } 361 errno = ENOENT; /* as if we called execvp */ 362 363 argv[0] = tmp; 364 365 strbuf_release(&cmd); 366 } 367 368 static int run_argv(int *argcp, const char ***argv) 369 { 370 int done_alias = 0; 371 372 while (1) { 373 /* See if it's an internal command */ 374 handle_internal_command(*argcp, *argv); 375 376 /* .. then try the external ones */ 377 execv_dashed_external(*argv); 378 379 /* It could be an alias -- this works around the insanity 380 * of overriding "perf log" with "perf show" by having 381 * alias.log = show 382 */ 383 if (done_alias || !handle_alias(argcp, argv)) 384 break; 385 done_alias = 1; 386 } 387 388 return done_alias; 389 } 390 391 /* mini /proc/mounts parser: searching for "^blah /mount/point debugfs" */ 392 static void get_debugfs_mntpt(void) 393 { 394 const char *path = debugfs_mount(NULL); 395 396 if (path) 397 strncpy(debugfs_mntpt, path, sizeof(debugfs_mntpt)); 398 else 399 debugfs_mntpt[0] = '\0'; 400 } 401 402 int main(int argc, const char **argv) 403 { 404 const char *cmd; 405 406 cmd = perf_extract_argv0_path(argv[0]); 407 if (!cmd) 408 cmd = "perf-help"; 409 /* get debugfs mount point from /proc/mounts */ 410 get_debugfs_mntpt(); 411 /* 412 * "perf-xxxx" is the same as "perf xxxx", but we obviously: 413 * 414 * - cannot take flags in between the "perf" and the "xxxx". 415 * - cannot execute it externally (since it would just do 416 * the same thing over again) 417 * 418 * So we just directly call the internal command handler, and 419 * die if that one cannot handle it. 420 */ 421 if (!prefixcmp(cmd, "perf-")) { 422 cmd += 5; 423 argv[0] = cmd; 424 handle_internal_command(argc, argv); 425 die("cannot handle %s internally", cmd); 426 } 427 428 /* Look for flags.. */ 429 argv++; 430 argc--; 431 handle_options(&argv, &argc, NULL); 432 commit_pager_choice(); 433 set_debugfs_path(); 434 if (argc > 0) { 435 if (!prefixcmp(argv[0], "--")) 436 argv[0] += 2; 437 } else { 438 /* The user didn't specify a command; give them help */ 439 printf("\n usage: %s\n\n", perf_usage_string); 440 list_common_cmds_help(); 441 printf("\n %s\n\n", perf_more_info_string); 442 exit(1); 443 } 444 cmd = argv[0]; 445 446 /* 447 * We use PATH to find perf commands, but we prepend some higher 448 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH 449 * environment, and the $(perfexecdir) from the Makefile at build 450 * time. 451 */ 452 setup_path(); 453 454 while (1) { 455 static int done_help; 456 static int was_alias; 457 458 was_alias = run_argv(&argc, &argv); 459 if (errno != ENOENT) 460 break; 461 462 if (was_alias) { 463 fprintf(stderr, "Expansion of alias '%s' failed; " 464 "'%s' is not a perf-command\n", 465 cmd, argv[0]); 466 exit(1); 467 } 468 if (!done_help) { 469 cmd = argv[0] = help_unknown_cmd(cmd); 470 done_help = 1; 471 } else 472 break; 473 } 474 475 fprintf(stderr, "Failed to run command '%s': %s\n", 476 cmd, strerror(errno)); 477 478 return 1; 479 } 480