1 /* 2 * builtin-probe.c 3 * 4 * Builtin probe command: Set up probe events by C expression 5 * 6 * Written by Masami Hiramatsu <mhiramat (at) redhat.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 21 * 22 */ 23 #include <sys/utsname.h> 24 #include <sys/types.h> 25 #include <sys/stat.h> 26 #include <fcntl.h> 27 #include <errno.h> 28 #include <stdio.h> 29 #include <unistd.h> 30 #include <stdlib.h> 31 #include <string.h> 32 33 #include "perf.h" 34 #include "builtin.h" 35 #include "util/util.h" 36 #include "util/strlist.h" 37 #include "util/strfilter.h" 38 #include "util/symbol.h" 39 #include "util/debug.h" 40 #include <lk/debugfs.h> 41 #include "util/parse-options.h" 42 #include "util/probe-finder.h" 43 #include "util/probe-event.h" 44 45 #define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*" 46 #define DEFAULT_FUNC_FILTER "!_*" 47 48 /* Session management structure */ 49 static struct { 50 bool list_events; 51 bool force_add; 52 bool show_lines; 53 bool show_vars; 54 bool show_ext_vars; 55 bool show_funcs; 56 bool mod_events; 57 bool uprobes; 58 int nevents; 59 struct perf_probe_event events[MAX_PROBES]; 60 struct strlist *dellist; 61 struct line_range line_range; 62 const char *target; 63 int max_probe_points; 64 struct strfilter *filter; 65 } params; 66 67 /* Parse an event definition. Note that any error must die. */ 68 static int parse_probe_event(const char *str) 69 { 70 struct perf_probe_event *pev = ¶ms.events[params.nevents]; 71 int ret; 72 73 pr_debug("probe-definition(%d): %s\n", params.nevents, str); 74 if (++params.nevents == MAX_PROBES) { 75 pr_err("Too many probes (> %d) were specified.", MAX_PROBES); 76 return -1; 77 } 78 79 pev->uprobes = params.uprobes; 80 81 /* Parse a perf-probe command into event */ 82 ret = parse_perf_probe_command(str, pev); 83 pr_debug("%d arguments\n", pev->nargs); 84 85 return ret; 86 } 87 88 static int set_target(const char *ptr) 89 { 90 int found = 0; 91 const char *buf; 92 93 /* 94 * The first argument after options can be an absolute path 95 * to an executable / library or kernel module. 96 * 97 * TODO: Support relative path, and $PATH, $LD_LIBRARY_PATH, 98 * short module name. 99 */ 100 if (!params.target && ptr && *ptr == '/') { 101 params.target = ptr; 102 found = 1; 103 buf = ptr + (strlen(ptr) - 3); 104 105 if (strcmp(buf, ".ko")) 106 params.uprobes = true; 107 108 } 109 110 return found; 111 } 112 113 static int parse_probe_event_argv(int argc, const char **argv) 114 { 115 int i, len, ret, found_target; 116 char *buf; 117 118 found_target = set_target(argv[0]); 119 if (found_target && argc == 1) 120 return 0; 121 122 /* Bind up rest arguments */ 123 len = 0; 124 for (i = 0; i < argc; i++) { 125 if (i == 0 && found_target) 126 continue; 127 128 len += strlen(argv[i]) + 1; 129 } 130 buf = zalloc(len + 1); 131 if (buf == NULL) 132 return -ENOMEM; 133 len = 0; 134 for (i = 0; i < argc; i++) { 135 if (i == 0 && found_target) 136 continue; 137 138 len += sprintf(&buf[len], "%s ", argv[i]); 139 } 140 params.mod_events = true; 141 ret = parse_probe_event(buf); 142 free(buf); 143 return ret; 144 } 145 146 static int opt_add_probe_event(const struct option *opt __maybe_unused, 147 const char *str, int unset __maybe_unused) 148 { 149 if (str) { 150 params.mod_events = true; 151 return parse_probe_event(str); 152 } else 153 return 0; 154 } 155 156 static int opt_del_probe_event(const struct option *opt __maybe_unused, 157 const char *str, int unset __maybe_unused) 158 { 159 if (str) { 160 params.mod_events = true; 161 if (!params.dellist) 162 params.dellist = strlist__new(true, NULL); 163 strlist__add(params.dellist, str); 164 } 165 return 0; 166 } 167 168 static int opt_set_target(const struct option *opt, const char *str, 169 int unset __maybe_unused) 170 { 171 int ret = -ENOENT; 172 173 if (str && !params.target) { 174 if (!strcmp(opt->long_name, "exec")) 175 params.uprobes = true; 176 #ifdef DWARF_SUPPORT 177 else if (!strcmp(opt->long_name, "module")) 178 params.uprobes = false; 179 #endif 180 else 181 return ret; 182 183 params.target = str; 184 ret = 0; 185 } 186 187 return ret; 188 } 189 190 #ifdef DWARF_SUPPORT 191 static int opt_show_lines(const struct option *opt __maybe_unused, 192 const char *str, int unset __maybe_unused) 193 { 194 int ret = 0; 195 196 if (!str) 197 return 0; 198 199 if (params.show_lines) { 200 pr_warning("Warning: more than one --line options are" 201 " detected. Only the first one is valid.\n"); 202 return 0; 203 } 204 205 params.show_lines = true; 206 ret = parse_line_range_desc(str, ¶ms.line_range); 207 INIT_LIST_HEAD(¶ms.line_range.line_list); 208 209 return ret; 210 } 211 212 static int opt_show_vars(const struct option *opt __maybe_unused, 213 const char *str, int unset __maybe_unused) 214 { 215 struct perf_probe_event *pev = ¶ms.events[params.nevents]; 216 int ret; 217 218 if (!str) 219 return 0; 220 221 ret = parse_probe_event(str); 222 if (!ret && pev->nargs != 0) { 223 pr_err(" Error: '--vars' doesn't accept arguments.\n"); 224 return -EINVAL; 225 } 226 params.show_vars = true; 227 228 return ret; 229 } 230 #endif 231 232 static int opt_set_filter(const struct option *opt __maybe_unused, 233 const char *str, int unset __maybe_unused) 234 { 235 const char *err; 236 237 if (str) { 238 pr_debug2("Set filter: %s\n", str); 239 if (params.filter) 240 strfilter__delete(params.filter); 241 params.filter = strfilter__new(str, &err); 242 if (!params.filter) { 243 pr_err("Filter parse error at %td.\n", err - str + 1); 244 pr_err("Source: \"%s\"\n", str); 245 pr_err(" %*c\n", (int)(err - str + 1), '^'); 246 return -EINVAL; 247 } 248 } 249 250 return 0; 251 } 252 253 int cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused) 254 { 255 const char * const probe_usage[] = { 256 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]", 257 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]", 258 "perf probe [<options>] --del '[GROUP:]EVENT' ...", 259 "perf probe --list", 260 #ifdef DWARF_SUPPORT 261 "perf probe [<options>] --line 'LINEDESC'", 262 "perf probe [<options>] --vars 'PROBEPOINT'", 263 #endif 264 NULL 265 }; 266 const struct option options[] = { 267 OPT_INCR('v', "verbose", &verbose, 268 "be more verbose (show parsed arguments, etc)"), 269 OPT_BOOLEAN('l', "list", ¶ms.list_events, 270 "list up current probe events"), 271 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.", 272 opt_del_probe_event), 273 OPT_CALLBACK('a', "add", NULL, 274 #ifdef DWARF_SUPPORT 275 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT" 276 " [[NAME=]ARG ...]", 277 #else 278 "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]", 279 #endif 280 "probe point definition, where\n" 281 "\t\tGROUP:\tGroup name (optional)\n" 282 "\t\tEVENT:\tEvent name\n" 283 "\t\tFUNC:\tFunction name\n" 284 "\t\tOFF:\tOffset from function entry (in byte)\n" 285 "\t\t%return:\tPut the probe at function return\n" 286 #ifdef DWARF_SUPPORT 287 "\t\tSRC:\tSource code path\n" 288 "\t\tRL:\tRelative line number from function entry.\n" 289 "\t\tAL:\tAbsolute line number in file.\n" 290 "\t\tPT:\tLazy expression of line code.\n" 291 "\t\tARG:\tProbe argument (local variable name or\n" 292 "\t\t\tkprobe-tracer argument format.)\n", 293 #else 294 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n", 295 #endif 296 opt_add_probe_event), 297 OPT_BOOLEAN('f', "force", ¶ms.force_add, "forcibly add events" 298 " with existing name"), 299 #ifdef DWARF_SUPPORT 300 OPT_CALLBACK('L', "line", NULL, 301 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]", 302 "Show source code lines.", opt_show_lines), 303 OPT_CALLBACK('V', "vars", NULL, 304 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT", 305 "Show accessible variables on PROBEDEF", opt_show_vars), 306 OPT_BOOLEAN('\0', "externs", ¶ms.show_ext_vars, 307 "Show external variables too (with --vars only)"), 308 OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name, 309 "file", "vmlinux pathname"), 310 OPT_STRING('s', "source", &symbol_conf.source_prefix, 311 "directory", "path to kernel source"), 312 OPT_CALLBACK('m', "module", NULL, "modname|path", 313 "target module name (for online) or path (for offline)", 314 opt_set_target), 315 #endif 316 OPT__DRY_RUN(&probe_event_dry_run), 317 OPT_INTEGER('\0', "max-probes", ¶ms.max_probe_points, 318 "Set how many probe points can be found for a probe."), 319 OPT_BOOLEAN('F', "funcs", ¶ms.show_funcs, 320 "Show potential probe-able functions."), 321 OPT_CALLBACK('\0', "filter", NULL, 322 "[!]FILTER", "Set a filter (with --vars/funcs only)\n" 323 "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n" 324 "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)", 325 opt_set_filter), 326 OPT_CALLBACK('x', "exec", NULL, "executable|path", 327 "target executable name or path", opt_set_target), 328 OPT_END() 329 }; 330 int ret; 331 332 argc = parse_options(argc, argv, options, probe_usage, 333 PARSE_OPT_STOP_AT_NON_OPTION); 334 if (argc > 0) { 335 if (strcmp(argv[0], "-") == 0) { 336 pr_warning(" Error: '-' is not supported.\n"); 337 usage_with_options(probe_usage, options); 338 } 339 ret = parse_probe_event_argv(argc, argv); 340 if (ret < 0) { 341 pr_err(" Error: Parse Error. (%d)\n", ret); 342 return ret; 343 } 344 } 345 346 if (params.max_probe_points == 0) 347 params.max_probe_points = MAX_PROBES; 348 349 if ((!params.nevents && !params.dellist && !params.list_events && 350 !params.show_lines && !params.show_funcs)) 351 usage_with_options(probe_usage, options); 352 353 /* 354 * Only consider the user's kernel image path if given. 355 */ 356 symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL); 357 358 if (params.list_events) { 359 if (params.mod_events) { 360 pr_err(" Error: Don't use --list with --add/--del.\n"); 361 usage_with_options(probe_usage, options); 362 } 363 if (params.show_lines) { 364 pr_err(" Error: Don't use --list with --line.\n"); 365 usage_with_options(probe_usage, options); 366 } 367 if (params.show_vars) { 368 pr_err(" Error: Don't use --list with --vars.\n"); 369 usage_with_options(probe_usage, options); 370 } 371 if (params.show_funcs) { 372 pr_err(" Error: Don't use --list with --funcs.\n"); 373 usage_with_options(probe_usage, options); 374 } 375 if (params.uprobes) { 376 pr_warning(" Error: Don't use --list with --exec.\n"); 377 usage_with_options(probe_usage, options); 378 } 379 ret = show_perf_probe_events(); 380 if (ret < 0) 381 pr_err(" Error: Failed to show event list. (%d)\n", 382 ret); 383 return ret; 384 } 385 if (params.show_funcs) { 386 if (params.nevents != 0 || params.dellist) { 387 pr_err(" Error: Don't use --funcs with" 388 " --add/--del.\n"); 389 usage_with_options(probe_usage, options); 390 } 391 if (params.show_lines) { 392 pr_err(" Error: Don't use --funcs with --line.\n"); 393 usage_with_options(probe_usage, options); 394 } 395 if (params.show_vars) { 396 pr_err(" Error: Don't use --funcs with --vars.\n"); 397 usage_with_options(probe_usage, options); 398 } 399 if (!params.filter) 400 params.filter = strfilter__new(DEFAULT_FUNC_FILTER, 401 NULL); 402 ret = show_available_funcs(params.target, params.filter, 403 params.uprobes); 404 strfilter__delete(params.filter); 405 if (ret < 0) 406 pr_err(" Error: Failed to show functions." 407 " (%d)\n", ret); 408 return ret; 409 } 410 411 #ifdef DWARF_SUPPORT 412 if (params.show_lines && !params.uprobes) { 413 if (params.mod_events) { 414 pr_err(" Error: Don't use --line with" 415 " --add/--del.\n"); 416 usage_with_options(probe_usage, options); 417 } 418 if (params.show_vars) { 419 pr_err(" Error: Don't use --line with --vars.\n"); 420 usage_with_options(probe_usage, options); 421 } 422 423 ret = show_line_range(¶ms.line_range, params.target); 424 if (ret < 0) 425 pr_err(" Error: Failed to show lines. (%d)\n", ret); 426 return ret; 427 } 428 if (params.show_vars) { 429 if (params.mod_events) { 430 pr_err(" Error: Don't use --vars with" 431 " --add/--del.\n"); 432 usage_with_options(probe_usage, options); 433 } 434 if (!params.filter) 435 params.filter = strfilter__new(DEFAULT_VAR_FILTER, 436 NULL); 437 438 ret = show_available_vars(params.events, params.nevents, 439 params.max_probe_points, 440 params.target, 441 params.filter, 442 params.show_ext_vars); 443 strfilter__delete(params.filter); 444 if (ret < 0) 445 pr_err(" Error: Failed to show vars. (%d)\n", ret); 446 return ret; 447 } 448 #endif 449 450 if (params.dellist) { 451 ret = del_perf_probe_events(params.dellist); 452 strlist__delete(params.dellist); 453 if (ret < 0) { 454 pr_err(" Error: Failed to delete events. (%d)\n", ret); 455 return ret; 456 } 457 } 458 459 if (params.nevents) { 460 ret = add_perf_probe_events(params.events, params.nevents, 461 params.max_probe_points, 462 params.target, 463 params.force_add); 464 if (ret < 0) { 465 pr_err(" Error: Failed to add events. (%d)\n", ret); 466 return ret; 467 } 468 } 469 return 0; 470 } 471
