tools/perf/builtin-probe.c

   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 <subcmd/parse-options.h>
  41 #include "util/probe-finder.h"
  42 #include "util/probe-event.h"
  43 #include "util/probe-file.h"
  44
  45 #define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*"
  46 #define DEFAULT_FUNC_FILTER "!_*"
  47 #define DEFAULT_LIST_FILTER "*"
  48
  49 /* Session management structure */
  50 static struct {
  51         int command;    /* Command short_name */
  52         bool list_events;
  53         bool uprobes;
  54         bool quiet;
  55         bool target_used;
  56         int nevents;
  57         struct perf_probe_event events[MAX_PROBES];
  58         struct line_range line_range;
  59         char *target;
  60         struct strfilter *filter;
  61         struct nsinfo *nsi;
  62 } params;
  63
  64 /* Parse an event definition. Note that any error must die. */
  65 static int parse_probe_event(const char *str)
  66 {
  67         struct perf_probe_event *pev = &params.events[params.nevents];
  68         int ret;
  69
  70         pr_debug("probe-definition(%d): %s\n", params.nevents, str);
  71         if (++params.nevents == MAX_PROBES) {
  72                 pr_err("Too many probes (> %d) were specified.", MAX_PROBES);
  73                 return -1;
  74         }
  75
  76         pev->uprobes = params.uprobes;
  77         if (params.target) {
  78                 pev->target = strdup(params.target);
  79                 if (!pev->target)
  80                         return -ENOMEM;
  81                 params.target_used = true;
  82         }
  83
  84         if (params.nsi)
  85                 pev->nsi = nsinfo__get(params.nsi);
  86
  87         /* Parse a perf-probe command into event */
  88         ret = parse_perf_probe_command(str, pev);
  89         pr_debug("%d arguments\n", pev->nargs);
  90
  91         return ret;
  92 }
  93
  94 static int params_add_filter(const char *str)
  95 {
  96         const char *err = NULL;
  97         int ret = 0;
  98
  99         pr_debug2("Add filter: %s\n", str);
 100         if (!params.filter) {
 101                 params.filter = strfilter__new(str, &err);
 102                 if (!params.filter)
 103                         ret = err ? -EINVAL : -ENOMEM;
 104         } else
 105                 ret = strfilter__or(params.filter, str, &err);
 106
 107         if (ret == -EINVAL) {
 108                 pr_err("Filter parse error at %td.\n", err - str + 1);
 109                 pr_err("Source: \"%s\"\n", str);
 110                 pr_err("         %*c\n", (int)(err - str + 1), '^');
 111         }
 112
 113         return ret;
 114 }
 115
 116 static int set_target(const char *ptr)
 117 {
 118         int found = 0;
 119         const char *buf;
 120
 121         /*
 122          * The first argument after options can be an absolute path
 123          * to an executable / library or kernel module.
 124          *
 125          * TODO: Support relative path, and $PATH, $LD_LIBRARY_PATH,
 126          * short module name.
 127          */
 128         if (!params.target && ptr && *ptr == '/') {
 129                 params.target = strdup(ptr);
 130                 if (!params.target)
 131                         return -ENOMEM;
 132                 params.target_used = false;
 133
 134                 found = 1;
 135                 buf = ptr + (strlen(ptr) - 3);
 136
 137                 if (strcmp(buf, ".ko"))
 138                         params.uprobes = true;
 139
 140         }
 141
 142         return found;
 143 }
 144
 145 static int parse_probe_event_argv(int argc, const char **argv)
 146 {
 147         int i, len, ret, found_target;
 148         char *buf;
 149
 150         found_target = set_target(argv[0]);
 151         if (found_target < 0)
 152                 return found_target;
 153
 154         if (found_target && argc == 1)
 155                 return 0;
 156
 157         /* Bind up rest arguments */
 158         len = 0;
 159         for (i = 0; i < argc; i++) {
 160                 if (i == 0 && found_target)
 161                         continue;
 162
 163                 len += strlen(argv[i]) + 1;
 164         }
 165         buf = zalloc(len + 1);
 166         if (buf == NULL)
 167                 return -ENOMEM;
 168         len = 0;
 169         for (i = 0; i < argc; i++) {
 170                 if (i == 0 && found_target)
 171                         continue;
 172
 173                 len += sprintf(&buf[len], "%s ", argv[i]);
 174         }
 175         ret = parse_probe_event(buf);
 176         free(buf);
 177         return ret;
 178 }
 179
 180 static int opt_set_target(const struct option *opt, const char *str,
 181                         int unset __maybe_unused)
 182 {
 183         int ret = -ENOENT;
 184         char *tmp;
 185
 186         if  (str) {
 187                 if (!strcmp(opt->long_name, "exec"))
 188                         params.uprobes = true;
 189                 else if (!strcmp(opt->long_name, "module"))
 190                         params.uprobes = false;
 191                 else
 192                         return ret;
 193
 194                 /* Expand given path to absolute path, except for modulename */
 195                 if (params.uprobes || strchr(str, '/')) {
 196                         tmp = nsinfo__realpath(str, params.nsi);
 197                         if (!tmp) {
 198                                 pr_warning("Failed to get the absolute path of %s: %m\n", str);
 199                                 return ret;
 200                         }
 201                 } else {
 202                         tmp = strdup(str);
 203                         if (!tmp)
 204                                 return -ENOMEM;
 205                 }
 206                 free(params.target);
 207                 params.target = tmp;
 208                 params.target_used = false;
 209                 ret = 0;
 210         }
 211
 212         return ret;
 213 }
 214
 215 static int opt_set_target_ns(const struct option *opt __maybe_unused,
 216                              const char *str, int unset __maybe_unused)
 217 {
 218         int ret = -ENOENT;
 219         pid_t ns_pid;
 220         struct nsinfo *nsip;
 221
 222         if (str) {
 223                 errno = 0;
 224                 ns_pid = (pid_t)strtol(str, NULL, 10);
 225                 if (errno != 0) {
 226                         ret = -errno;
 227                         pr_warning("Failed to parse %s as a pid: %s\n", str,
 228                                    strerror(errno));
 229                         return ret;
 230                 }
 231                 nsip = nsinfo__new(ns_pid);
 232                 if (nsip && nsip->need_setns)
 233                         params.nsi = nsinfo__get(nsip);
 234                 nsinfo__put(nsip);
 235
 236                 ret = 0;
 237         }
 238
 239         return ret;
 240 }
 241
 242
 243 /* Command option callbacks */
 244
 245 #ifdef HAVE_DWARF_SUPPORT
 246 static int opt_show_lines(const struct option *opt,
 247                           const char *str, int unset __maybe_unused)
 248 {
 249         int ret = 0;
 250
 251         if (!str)
 252                 return 0;
 253
 254         if (params.command == 'L') {
 255                 pr_warning("Warning: more than one --line options are"
 256                            " detected. Only the first one is valid.\n");
 257                 return 0;
 258         }
 259
 260         params.command = opt->short_name;
 261         ret = parse_line_range_desc(str, &params.line_range);
 262
 263         return ret;
 264 }
 265
 266 static int opt_show_vars(const struct option *opt,
 267                          const char *str, int unset __maybe_unused)
 268 {
 269         struct perf_probe_event *pev = &params.events[params.nevents];
 270         int ret;
 271
 272         if (!str)
 273                 return 0;
 274
 275         ret = parse_probe_event(str);
 276         if (!ret && pev->nargs != 0) {
 277                 pr_err("  Error: '--vars' doesn't accept arguments.\n");
 278                 return -EINVAL;
 279         }
 280         params.command = opt->short_name;
 281
 282         return ret;
 283 }
 284 #else
 285 # define opt_show_lines NULL
 286 # define opt_show_vars NULL
 287 #endif
 288 static int opt_add_probe_event(const struct option *opt,
 289                               const char *str, int unset __maybe_unused)
 290 {
 291         if (str) {
 292                 params.command = opt->short_name;
 293                 return parse_probe_event(str);
 294         }
 295
 296         return 0;
 297 }
 298
 299 static int opt_set_filter_with_command(const struct option *opt,
 300                                        const char *str, int unset)
 301 {
 302         if (!unset)
 303                 params.command = opt->short_name;
 304
 305         if (str)
 306                 return params_add_filter(str);
 307
 308         return 0;
 309 }
 310
 311 static int opt_set_filter(const struct option *opt __maybe_unused,
 312                           const char *str, int unset __maybe_unused)
 313 {
 314         if (str)
 315                 return params_add_filter(str);
 316
 317         return 0;
 318 }
 319
 320 static int init_params(void)
 321 {
 322         return line_range__init(&params.line_range);
 323 }
 324
 325 static void cleanup_params(void)
 326 {
 327         int i;
 328
 329         for (i = 0; i < params.nevents; i++)
 330                 clear_perf_probe_event(params.events + i);
 331         line_range__clear(&params.line_range);
 332         free(params.target);
 333         strfilter__delete(params.filter);
 334         nsinfo__put(params.nsi);
 335         memset(&params, 0, sizeof(params));
 336 }
 337
 338 static void pr_err_with_code(const char *msg, int err)
 339 {
 340         char sbuf[STRERR_BUFSIZE];
 341
 342         pr_err("%s", msg);
 343         pr_debug(" Reason: %s (Code: %d)",
 344                  str_error_r(-err, sbuf, sizeof(sbuf)), err);
 345         pr_err("\n");
 346 }
 347
 348 static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
 349 {
 350         int ret;
 351         int i, k;
 352         const char *event = NULL, *group = NULL;
 353
 354         ret = init_probe_symbol_maps(pevs->uprobes);
 355         if (ret < 0)
 356                 return ret;
 357
 358         ret = convert_perf_probe_events(pevs, npevs);
 359         if (ret < 0)
 360                 goto out_cleanup;
 361
 362         if (params.command == 'D') {    /* it shows definition */
 363                 ret = show_probe_trace_events(pevs, npevs);
 364                 goto out_cleanup;
 365         }
 366
 367         ret = apply_perf_probe_events(pevs, npevs);
 368         if (ret < 0)
 369                 goto out_cleanup;
 370
 371         for (i = k = 0; i < npevs; i++)
 372                 k += pevs[i].ntevs;
 373
 374         pr_info("Added new event%s\n", (k > 1) ? "s:" : ":");
 375         for (i = 0; i < npevs; i++) {
 376                 struct perf_probe_event *pev = &pevs[i];
 377
 378                 for (k = 0; k < pev->ntevs; k++) {
 379                         struct probe_trace_event *tev = &pev->tevs[k];
 380
 381                         /* We use tev's name for showing new events */
 382                         show_perf_probe_event(tev->group, tev->event, pev,
 383                                               tev->point.module, false);
 384
 385                         /* Save the last valid name */
 386                         event = tev->event;
 387                         group = tev->group;
 388                 }
 389         }
 390
 391         /* Note that it is possible to skip all events because of blacklist */
 392         if (event) {
 393                 /* Show how to use the event. */
 394                 pr_info("\nYou can now use it in all perf tools, such as:\n\n");
 395                 pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group, event);
 396         }
 397
 398 out_cleanup:
 399         cleanup_perf_probe_events(pevs, npevs);
 400         exit_probe_symbol_maps();
 401         return ret;
 402 }
 403
 404 static int del_perf_probe_caches(struct strfilter *filter)
 405 {
 406         struct probe_cache *cache;
 407         struct strlist *bidlist;
 408         struct str_node *nd;
 409         int ret;
 410
 411         bidlist = build_id_cache__list_all(false);
 412         if (!bidlist) {
 413                 ret = -errno;
 414                 pr_debug("Failed to get buildids: %d\n", ret);
 415                 return ret ?: -ENOMEM;
 416         }
 417
 418         strlist__for_each_entry(nd, bidlist) {
 419                 cache = probe_cache__new(nd->s, NULL);
 420                 if (!cache)
 421                         continue;
 422                 if (probe_cache__filter_purge(cache, filter) < 0 ||
 423                     probe_cache__commit(cache) < 0)
 424                         pr_warning("Failed to remove entries for %s\n", nd->s);
 425                 probe_cache__delete(cache);
 426         }
 427         return 0;
 428 }
 429
 430 static int perf_del_probe_events(struct strfilter *filter)
 431 {
 432         int ret, ret2, ufd = -1, kfd = -1;
 433         char *str = strfilter__string(filter);
 434         struct strlist *klist = NULL, *ulist = NULL;
 435         struct str_node *ent;
 436
 437         if (!str)
 438                 return -EINVAL;
 439
 440         pr_debug("Delete filter: \'%s\'\n", str);
 441
 442         if (probe_conf.cache)
 443                 return del_perf_probe_caches(filter);
 444
 445         /* Get current event names */
 446         ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
 447         if (ret < 0)
 448                 goto out;
 449
 450         klist = strlist__new(NULL, NULL);
 451         ulist = strlist__new(NULL, NULL);
 452         if (!klist || !ulist) {
 453                 ret = -ENOMEM;
 454                 goto out;
 455         }
 456
 457         ret = probe_file__get_events(kfd, filter, klist);
 458         if (ret == 0) {
 459                 strlist__for_each_entry(ent, klist)
 460                         pr_info("Removed event: %s\n", ent->s);
 461
 462                 ret = probe_file__del_strlist(kfd, klist);
 463                 if (ret < 0)
 464                         goto error;
 465         }
 466
 467         ret2 = probe_file__get_events(ufd, filter, ulist);
 468         if (ret2 == 0) {
 469                 strlist__for_each_entry(ent, ulist)
 470                         pr_info("Removed event: %s\n", ent->s);
 471
 472                 ret2 = probe_file__del_strlist(ufd, ulist);
 473                 if (ret2 < 0)
 474                         goto error;
 475         }
 476
 477         if (ret == -ENOENT && ret2 == -ENOENT)
 478                 pr_warning("\"%s\" does not hit any event.\n", str);
 479         else
 480                 ret = 0;
 481
 482 error:
 483         if (kfd >= 0)
 484                 close(kfd);
 485         if (ufd >= 0)
 486                 close(ufd);
 487 out:
 488         strlist__delete(klist);
 489         strlist__delete(ulist);
 490         free(str);
 491
 492         return ret;
 493 }
 494
 495 #ifdef HAVE_DWARF_SUPPORT
 496 #define PROBEDEF_STR    \
 497         "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
 498 #else
 499 #define PROBEDEF_STR    "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
 500 #endif
 501
 502
 503 static int
 504 __cmd_probe(int argc, const char **argv)
 505 {
 506         const char * const probe_usage[] = {
 507                 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
 508                 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
 509                 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
 510                 "perf probe --list [GROUP:]EVENT ...",
 511 #ifdef HAVE_DWARF_SUPPORT
 512                 "perf probe [<options>] --line 'LINEDESC'",
 513                 "perf probe [<options>] --vars 'PROBEPOINT'",
 514 #endif
 515                 "perf probe [<options>] --funcs",
 516                 NULL
 517         };
 518         struct option options[] = {
 519         OPT_INCR('v', "verbose", &verbose,
 520                     "be more verbose (show parsed arguments, etc)"),
 521         OPT_BOOLEAN('q', "quiet", &params.quiet,
 522                     "be quiet (do not show any messages)"),
 523         OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
 524                              "list up probe events",
 525                              opt_set_filter_with_command, DEFAULT_LIST_FILTER),
 526         OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
 527                      opt_set_filter_with_command),
 528         OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,
 529                 "probe point definition, where\n"
 530                 "\t\tGROUP:\tGroup name (optional)\n"
 531                 "\t\tEVENT:\tEvent name\n"
 532                 "\t\tFUNC:\tFunction name\n"
 533                 "\t\tOFF:\tOffset from function entry (in byte)\n"
 534                 "\t\t%return:\tPut the probe at function return\n"
 535 #ifdef HAVE_DWARF_SUPPORT
 536                 "\t\tSRC:\tSource code path\n"
 537                 "\t\tRL:\tRelative line number from function entry.\n"
 538                 "\t\tAL:\tAbsolute line number in file.\n"
 539                 "\t\tPT:\tLazy expression of line code.\n"
 540                 "\t\tARG:\tProbe argument (local variable name or\n"
 541                 "\t\t\tkprobe-tracer argument format.)\n",
 542 #else
 543                 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
 544 #endif
 545                 opt_add_probe_event),
 546         OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,
 547                 "Show trace event definition of given traceevent for k/uprobe_events.",
 548                 opt_add_probe_event),
 549         OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
 550                     " with existing name"),
 551         OPT_CALLBACK('L', "line", NULL,
 552                      "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
 553                      "Show source code lines.", opt_show_lines),
 554         OPT_CALLBACK('V', "vars", NULL,
 555                      "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
 556                      "Show accessible variables on PROBEDEF", opt_show_vars),
 557         OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
 558                     "Show external variables too (with --vars only)"),
 559         OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
 560                 "Show variables location range in scope (with --vars only)"),
 561         OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
 562                    "file", "vmlinux pathname"),
 563         OPT_STRING('s', "source", &symbol_conf.source_prefix,
 564                    "directory", "path to kernel source"),
 565         OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
 566                 "Don't search inlined functions"),
 567         OPT__DRY_RUN(&probe_event_dry_run),
 568         OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
 569                  "Set how many probe points can be found for a probe."),
 570         OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
 571                              "Show potential probe-able functions.",
 572                              opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
 573         OPT_CALLBACK('\0', "filter", NULL,
 574                      "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
 575                      "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
 576                      "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
 577                      opt_set_filter),
 578         OPT_CALLBACK('x', "exec", NULL, "executable|path",
 579                         "target executable name or path", opt_set_target),
 580         OPT_CALLBACK('m', "module", NULL, "modname|path",
 581                 "target module name (for online) or path (for offline)",
 582                 opt_set_target),
 583         OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
 584                     "Enable symbol demangling"),
 585         OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
 586                     "Enable kernel symbol demangling"),
 587         OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
 588         OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
 589                    "Look for files with symbols relative to this directory"),
 590         OPT_CALLBACK(0, "target-ns", NULL, "pid",
 591                      "target pid for namespace contexts", opt_set_target_ns),
 592         OPT_END()
 593         };
 594         int ret;
 595
 596         set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
 597         set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
 598         set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);
 599         set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
 600 #ifdef HAVE_DWARF_SUPPORT
 601         set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
 602         set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
 603 #else
 604 # define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_DWARF=1", c)
 605         set_nobuild('L', "line", false);
 606         set_nobuild('V', "vars", false);
 607         set_nobuild('\0', "externs", false);
 608         set_nobuild('\0', "range", false);
 609         set_nobuild('k', "vmlinux", true);
 610         set_nobuild('s', "source", true);
 611         set_nobuild('\0', "no-inlines", true);
 612 # undef set_nobuild
 613 #endif
 614         set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);
 615
 616         argc = parse_options(argc, argv, options, probe_usage,
 617                              PARSE_OPT_STOP_AT_NON_OPTION);
 618         if (argc > 0) {
 619                 if (strcmp(argv[0], "-") == 0) {
 620                         usage_with_options_msg(probe_usage, options,
 621                                 "'-' is not supported.\n");
 622                 }
 623                 if (params.command && params.command != 'a') {
 624                         usage_with_options_msg(probe_usage, options,
 625                                 "another command except --add is set.\n");
 626                 }
 627                 ret = parse_probe_event_argv(argc, argv);
 628                 if (ret < 0) {
 629                         pr_err_with_code("  Error: Command Parse Error.", ret);
 630                         return ret;
 631                 }
 632                 params.command = 'a';
 633         }
 634
 635         if (params.quiet) {
 636                 if (verbose != 0) {
 637                         pr_err("  Error: -v and -q are exclusive.\n");
 638                         return -EINVAL;
 639                 }
 640                 verbose = -1;
 641         }
 642
 643         if (probe_conf.max_probes == 0)
 644                 probe_conf.max_probes = MAX_PROBES;
 645
 646         /*
 647          * Only consider the user's kernel image path if given.
 648          */
 649         symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
 650
 651         /*
 652          * Except for --list, --del and --add, other command doesn't depend
 653          * nor change running kernel. So if user gives offline vmlinux,
 654          * ignore its buildid.
 655          */
 656         if (!strchr("lda", params.command) && symbol_conf.vmlinux_name)
 657                 symbol_conf.ignore_vmlinux_buildid = true;
 658
 659         switch (params.command) {
 660         case 'l':
 661                 if (params.uprobes) {
 662                         pr_err("  Error: Don't use --list with --exec.\n");
 663                         parse_options_usage(probe_usage, options, "l", true);
 664                         parse_options_usage(NULL, options, "x", true);
 665                         return -EINVAL;
 666                 }
 667                 ret = show_perf_probe_events(params.filter);
 668                 if (ret < 0)
 669                         pr_err_with_code("  Error: Failed to show event list.", ret);
 670                 return ret;
 671         case 'F':
 672                 ret = show_available_funcs(params.target, params.nsi,
 673                                            params.filter, params.uprobes);
 674                 if (ret < 0)
 675                         pr_err_with_code("  Error: Failed to show functions.", ret);
 676                 return ret;
 677 #ifdef HAVE_DWARF_SUPPORT
 678         case 'L':
 679                 ret = show_line_range(&params.line_range, params.target,
 680                                       params.nsi, params.uprobes);
 681                 if (ret < 0)
 682                         pr_err_with_code("  Error: Failed to show lines.", ret);
 683                 return ret;
 684         case 'V':
 685                 if (!params.filter)
 686                         params.filter = strfilter__new(DEFAULT_VAR_FILTER,
 687                                                        NULL);
 688
 689                 ret = show_available_vars(params.events, params.nevents,
 690                                           params.filter);
 691                 if (ret < 0)
 692                         pr_err_with_code("  Error: Failed to show vars.", ret);
 693                 return ret;
 694 #endif
 695         case 'd':
 696                 ret = perf_del_probe_events(params.filter);
 697                 if (ret < 0) {
 698                         pr_err_with_code("  Error: Failed to delete events.", ret);
 699                         return ret;
 700                 }
 701                 break;
 702         case 'D':
 703         case 'a':
 704
 705                 /* Ensure the last given target is used */
 706                 if (params.target && !params.target_used) {
 707                         pr_err("  Error: -x/-m must follow the probe definitions.\n");
 708                         parse_options_usage(probe_usage, options, "m", true);
 709                         parse_options_usage(NULL, options, "x", true);
 710                         return -EINVAL;
 711                 }
 712
 713                 ret = perf_add_probe_events(params.events, params.nevents);
 714                 if (ret < 0) {
 715                         pr_err_with_code("  Error: Failed to add events.", ret);
 716                         return ret;
 717                 }
 718                 break;
 719         default:
 720                 usage_with_options(probe_usage, options);
 721         }
 722         return 0;
 723 }
 724
 725 int cmd_probe(int argc, const char **argv)
 726 {
 727         int ret;
 728
 729         ret = init_params();
 730         if (!ret) {
 731                 ret = __cmd_probe(argc, argv);
 732                 cleanup_params();
 733         }
 734
 735         return ret < 0 ? ret : 0;
 736 }