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