1 /* 2 * builtin-probe.c 3 * 4 * Builtin probe command: Set up probe events by C expression 5 * 6 * Written by Masami Hiramatsu <mhiramat@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 "util/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 int nevents; 58 struct perf_probe_event events[MAX_PROBES]; 59 struct strlist *dellist; 60 struct line_range line_range; 61 const char *target; 62 int max_probe_points; 63 struct strfilter *filter; 64 } params; 65 66 /* Parse an event definition. Note that any error must die. */ 67 static int parse_probe_event(const char *str) 68 { 69 struct perf_probe_event *pev = ¶ms.events[params.nevents]; 70 int ret; 71 72 pr_debug("probe-definition(%d): %s\n", params.nevents, str); 73 if (++params.nevents == MAX_PROBES) { 74 pr_err("Too many probes (> %d) were specified.", MAX_PROBES); 75 return -1; 76 } 77 78 /* Parse a perf-probe command into event */ 79 ret = parse_perf_probe_command(str, pev); 80 pr_debug("%d arguments\n", pev->nargs); 81 82 return ret; 83 } 84 85 static int parse_probe_event_argv(int argc, const char **argv) 86 { 87 int i, len, ret; 88 char *buf; 89 90 /* Bind up rest arguments */ 91 len = 0; 92 for (i = 0; i < argc; i++) 93 len += strlen(argv[i]) + 1; 94 buf = zalloc(len + 1); 95 if (buf == NULL) 96 return -ENOMEM; 97 len = 0; 98 for (i = 0; i < argc; i++) 99 len += sprintf(&buf[len], "%s ", argv[i]); 100 params.mod_events = true; 101 ret = parse_probe_event(buf); 102 free(buf); 103 return ret; 104 } 105 106 static int opt_add_probe_event(const struct option *opt __used, 107 const char *str, int unset __used) 108 { 109 if (str) { 110 params.mod_events = true; 111 return parse_probe_event(str); 112 } else 113 return 0; 114 } 115 116 static int opt_del_probe_event(const struct option *opt __used, 117 const char *str, int unset __used) 118 { 119 if (str) { 120 params.mod_events = true; 121 if (!params.dellist) 122 params.dellist = strlist__new(true, NULL); 123 strlist__add(params.dellist, str); 124 } 125 return 0; 126 } 127 128 #ifdef DWARF_SUPPORT 129 static int opt_show_lines(const struct option *opt __used, 130 const char *str, int unset __used) 131 { 132 int ret = 0; 133 134 if (!str) 135 return 0; 136 137 if (params.show_lines) { 138 pr_warning("Warning: more than one --line options are" 139 " detected. Only the first one is valid.\n"); 140 return 0; 141 } 142 143 params.show_lines = true; 144 ret = parse_line_range_desc(str, ¶ms.line_range); 145 INIT_LIST_HEAD(¶ms.line_range.line_list); 146 147 return ret; 148 } 149 150 static int opt_show_vars(const struct option *opt __used, 151 const char *str, int unset __used) 152 { 153 struct perf_probe_event *pev = ¶ms.events[params.nevents]; 154 int ret; 155 156 if (!str) 157 return 0; 158 159 ret = parse_probe_event(str); 160 if (!ret && pev->nargs != 0) { 161 pr_err(" Error: '--vars' doesn't accept arguments.\n"); 162 return -EINVAL; 163 } 164 params.show_vars = true; 165 166 return ret; 167 } 168 #endif 169 170 static int opt_set_filter(const struct option *opt __used, 171 const char *str, int unset __used) 172 { 173 const char *err; 174 175 if (str) { 176 pr_debug2("Set filter: %s\n", str); 177 if (params.filter) 178 strfilter__delete(params.filter); 179 params.filter = strfilter__new(str, &err); 180 if (!params.filter) { 181 pr_err("Filter parse error at %td.\n", err - str + 1); 182 pr_err("Source: \"%s\"\n", str); 183 pr_err(" %*c\n", (int)(err - str + 1), '^'); 184 return -EINVAL; 185 } 186 } 187 188 return 0; 189 } 190 191 static const char * const probe_usage[] = { 192 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]", 193 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]", 194 "perf probe [<options>] --del '[GROUP:]EVENT' ...", 195 "perf probe --list", 196 #ifdef DWARF_SUPPORT 197 "perf probe [<options>] --line 'LINEDESC'", 198 "perf probe [<options>] --vars 'PROBEPOINT'", 199 #endif 200 NULL 201 }; 202 203 static const struct option options[] = { 204 OPT_INCR('v', "verbose", &verbose, 205 "be more verbose (show parsed arguments, etc)"), 206 OPT_BOOLEAN('l', "list", ¶ms.list_events, 207 "list up current probe events"), 208 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.", 209 opt_del_probe_event), 210 OPT_CALLBACK('a', "add", NULL, 211 #ifdef DWARF_SUPPORT 212 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT" 213 " [[NAME=]ARG ...]", 214 #else 215 "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]", 216 #endif 217 "probe point definition, where\n" 218 "\t\tGROUP:\tGroup name (optional)\n" 219 "\t\tEVENT:\tEvent name\n" 220 "\t\tFUNC:\tFunction name\n" 221 "\t\tOFF:\tOffset from function entry (in byte)\n" 222 "\t\t%return:\tPut the probe at function return\n" 223 #ifdef DWARF_SUPPORT 224 "\t\tSRC:\tSource code path\n" 225 "\t\tRL:\tRelative line number from function entry.\n" 226 "\t\tAL:\tAbsolute line number in file.\n" 227 "\t\tPT:\tLazy expression of line code.\n" 228 "\t\tARG:\tProbe argument (local variable name or\n" 229 "\t\t\tkprobe-tracer argument format.)\n", 230 #else 231 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n", 232 #endif 233 opt_add_probe_event), 234 OPT_BOOLEAN('f', "force", ¶ms.force_add, "forcibly add events" 235 " with existing name"), 236 #ifdef DWARF_SUPPORT 237 OPT_CALLBACK('L', "line", NULL, 238 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]", 239 "Show source code lines.", opt_show_lines), 240 OPT_CALLBACK('V', "vars", NULL, 241 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT", 242 "Show accessible variables on PROBEDEF", opt_show_vars), 243 OPT_BOOLEAN('\0', "externs", ¶ms.show_ext_vars, 244 "Show external variables too (with --vars only)"), 245 OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name, 246 "file", "vmlinux pathname"), 247 OPT_STRING('s', "source", &symbol_conf.source_prefix, 248 "directory", "path to kernel source"), 249 OPT_STRING('m', "module", ¶ms.target, 250 "modname|path", 251 "target module name (for online) or path (for offline)"), 252 #endif 253 OPT__DRY_RUN(&probe_event_dry_run), 254 OPT_INTEGER('\0', "max-probes", ¶ms.max_probe_points, 255 "Set how many probe points can be found for a probe."), 256 OPT_BOOLEAN('F', "funcs", ¶ms.show_funcs, 257 "Show potential probe-able functions."), 258 OPT_CALLBACK('\0', "filter", NULL, 259 "[!]FILTER", "Set a filter (with --vars/funcs only)\n" 260 "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n" 261 "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)", 262 opt_set_filter), 263 OPT_END() 264 }; 265 266 int cmd_probe(int argc, const char **argv, const char *prefix __used) 267 { 268 int ret; 269 270 argc = parse_options(argc, argv, options, probe_usage, 271 PARSE_OPT_STOP_AT_NON_OPTION); 272 if (argc > 0) { 273 if (strcmp(argv[0], "-") == 0) { 274 pr_warning(" Error: '-' is not supported.\n"); 275 usage_with_options(probe_usage, options); 276 } 277 ret = parse_probe_event_argv(argc, argv); 278 if (ret < 0) { 279 pr_err(" Error: Parse Error. (%d)\n", ret); 280 return ret; 281 } 282 } 283 284 if (params.max_probe_points == 0) 285 params.max_probe_points = MAX_PROBES; 286 287 if ((!params.nevents && !params.dellist && !params.list_events && 288 !params.show_lines && !params.show_funcs)) 289 usage_with_options(probe_usage, options); 290 291 /* 292 * Only consider the user's kernel image path if given. 293 */ 294 symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL); 295 296 if (params.list_events) { 297 if (params.mod_events) { 298 pr_err(" Error: Don't use --list with --add/--del.\n"); 299 usage_with_options(probe_usage, options); 300 } 301 if (params.show_lines) { 302 pr_err(" Error: Don't use --list with --line.\n"); 303 usage_with_options(probe_usage, options); 304 } 305 if (params.show_vars) { 306 pr_err(" Error: Don't use --list with --vars.\n"); 307 usage_with_options(probe_usage, options); 308 } 309 if (params.show_funcs) { 310 pr_err(" Error: Don't use --list with --funcs.\n"); 311 usage_with_options(probe_usage, options); 312 } 313 ret = show_perf_probe_events(); 314 if (ret < 0) 315 pr_err(" Error: Failed to show event list. (%d)\n", 316 ret); 317 return ret; 318 } 319 if (params.show_funcs) { 320 if (params.nevents != 0 || params.dellist) { 321 pr_err(" Error: Don't use --funcs with" 322 " --add/--del.\n"); 323 usage_with_options(probe_usage, options); 324 } 325 if (params.show_lines) { 326 pr_err(" Error: Don't use --funcs with --line.\n"); 327 usage_with_options(probe_usage, options); 328 } 329 if (params.show_vars) { 330 pr_err(" Error: Don't use --funcs with --vars.\n"); 331 usage_with_options(probe_usage, options); 332 } 333 if (!params.filter) 334 params.filter = strfilter__new(DEFAULT_FUNC_FILTER, 335 NULL); 336 ret = show_available_funcs(params.target, 337 params.filter); 338 strfilter__delete(params.filter); 339 if (ret < 0) 340 pr_err(" Error: Failed to show functions." 341 " (%d)\n", ret); 342 return ret; 343 } 344 345 #ifdef DWARF_SUPPORT 346 if (params.show_lines) { 347 if (params.mod_events) { 348 pr_err(" Error: Don't use --line with" 349 " --add/--del.\n"); 350 usage_with_options(probe_usage, options); 351 } 352 if (params.show_vars) { 353 pr_err(" Error: Don't use --line with --vars.\n"); 354 usage_with_options(probe_usage, options); 355 } 356 357 ret = show_line_range(¶ms.line_range, params.target); 358 if (ret < 0) 359 pr_err(" Error: Failed to show lines. (%d)\n", ret); 360 return ret; 361 } 362 if (params.show_vars) { 363 if (params.mod_events) { 364 pr_err(" Error: Don't use --vars with" 365 " --add/--del.\n"); 366 usage_with_options(probe_usage, options); 367 } 368 if (!params.filter) 369 params.filter = strfilter__new(DEFAULT_VAR_FILTER, 370 NULL); 371 372 ret = show_available_vars(params.events, params.nevents, 373 params.max_probe_points, 374 params.target, 375 params.filter, 376 params.show_ext_vars); 377 strfilter__delete(params.filter); 378 if (ret < 0) 379 pr_err(" Error: Failed to show vars. (%d)\n", ret); 380 return ret; 381 } 382 #endif 383 384 if (params.dellist) { 385 ret = del_perf_probe_events(params.dellist); 386 strlist__delete(params.dellist); 387 if (ret < 0) { 388 pr_err(" Error: Failed to delete events. (%d)\n", ret); 389 return ret; 390 } 391 } 392 393 if (params.nevents) { 394 ret = add_perf_probe_events(params.events, params.nevents, 395 params.max_probe_points, 396 params.target, 397 params.force_add); 398 if (ret < 0) { 399 pr_err(" Error: Failed to add events. (%d)\n", ret); 400 return ret; 401 } 402 } 403 return 0; 404 } 405