lttng/commands/enable_events.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; only version 2
   7  * of the License.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <popt.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <sys/stat.h>
  25 #include <sys/types.h>
  26 #include <unistd.h>
  27 #include <inttypes.h>
  28 #include <ctype.h>
  29
  30 #include "../cmd.h"
  31 #include "../conf.h"
  32 #include "../utils.h"
  33
  34 static char *opt_event_list;
  35 static int opt_event_type;
  36 static int opt_kernel;
  37 static char *opt_session_name;
  38 static int opt_userspace;
  39 static char *opt_cmd_name;
  40 static int opt_enable_all;
  41 static pid_t opt_pid;
  42 static char *opt_probe;
  43 static char *opt_function;
  44 static char *opt_function_entry_symbol;
  45 static char *opt_channel_name;
  46
  47 enum {
  48         OPT_HELP = 1,
  49         OPT_TRACEPOINT,
  50         OPT_PROBE,
  51         OPT_FUNCTION,
  52         OPT_FUNCTION_ENTRY,
  53         OPT_SYSCALL,
  54         OPT_USERSPACE,
  55         OPT_TRACEPOINT_LOGLEVEL,
  56 };
  57
  58 static struct lttng_handle *handle;
  59
  60 static struct poptOption long_options[] = {
  61         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  62         {"help",           'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  63         {"session",        's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  64         {"all",            'a', POPT_ARG_VAL, &opt_enable_all, 1, 0, 0},
  65         {"channel",        'c', POPT_ARG_STRING, &opt_channel_name, 0, 0, 0},
  66         {"kernel",         'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
  67         {"userspace",      'u', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_cmd_name, OPT_USERSPACE, 0, 0},
  68         {"pid",            'p', POPT_ARG_INT, &opt_pid, 0, 0, 0},
  69         {"tracepoint",     0,   POPT_ARG_NONE, 0, OPT_TRACEPOINT, 0, 0},
  70         {"probe",          0,   POPT_ARG_STRING, &opt_probe, OPT_PROBE, 0, 0},
  71         {"function",       0,   POPT_ARG_STRING, &opt_function, OPT_FUNCTION, 0, 0},
  72 #if 0
  73         /*
  74          * Currently removed from lttng kernel tracer. Removed from
  75          * lttng UI to discourage its use.
  76          */
  77         {"function:entry", 0,   POPT_ARG_STRING, &opt_function_entry_symbol, OPT_FUNCTION_ENTRY, 0, 0},
  78 #endif
  79         {"syscall",        0,   POPT_ARG_NONE, 0, OPT_SYSCALL, 0, 0},
  80         {"loglevel",     0,     POPT_ARG_NONE, 0, OPT_TRACEPOINT_LOGLEVEL, 0, 0},
  81         {0, 0, 0, 0, 0, 0, 0}
  82 };
  83
  84 /*
  85  * usage
  86  */
  87 static void usage(FILE *ofp)
  88 {
  89         fprintf(ofp, "usage: lttng enable-event NAME[,NAME2,...] [options] [event_options]\n");
  90         fprintf(ofp, "\n");
  91         fprintf(ofp, "  -h, --help               Show this help\n");
  92         fprintf(ofp, "  -s, --session            Apply on session name\n");
  93         fprintf(ofp, "  -c, --channel            Apply on this channel\n");
  94         fprintf(ofp, "  -a, --all                Enable all tracepoints\n");
  95         fprintf(ofp, "  -k, --kernel             Apply for the kernel tracer\n");
  96         fprintf(ofp, "  -u, --userspace [CMD]    Apply for the user-space tracer\n");
  97         fprintf(ofp, "                           If no CMD, the domain used is UST global\n");
  98         fprintf(ofp, "                           or else the domain is UST EXEC_NAME\n");
  99         fprintf(ofp, "  -p, --pid PID            If -u, apply to specific PID (domain: UST PID)\n");
 100         fprintf(ofp, "\n");
 101         fprintf(ofp, "Event options:\n");
 102         fprintf(ofp, "    --tracepoint           Tracepoint event (default)\n");
 103         fprintf(ofp, "                           - userspace tracer supports wildcards at end of string.\n");
 104         fprintf(ofp, "                             Don't forget to quote to deal with bash expansion.\n");
 105         fprintf(ofp, "                             e.g.:\n");
 106         fprintf(ofp, "                               \"*\"\n");
 107         fprintf(ofp, "                               \"app_component:na*\"\n");
 108         fprintf(ofp, "    --loglevel             Tracepoint loglevel\n");
 109         fprintf(ofp, "    --probe [addr | symbol | symbol+offset]\n");
 110         fprintf(ofp, "                           Dynamic probe.\n");
 111         fprintf(ofp, "                           Addr and offset can be octal (0NNN...),\n");
 112         fprintf(ofp, "                           decimal (NNN...) or hexadecimal (0xNNN...)\n");
 113         fprintf(ofp, "    --function [addr | symbol | symbol+offset]\n");
 114         fprintf(ofp, "                           Dynamic function entry/return probe.\n");
 115         fprintf(ofp, "                           Addr and offset can be octal (0NNN...),\n");
 116         fprintf(ofp, "                           decimal (NNN...) or hexadecimal (0xNNN...)\n");
 117 #if 0
 118         fprintf(ofp, "    --function:entry symbol\n");
 119         fprintf(ofp, "                           Function tracer event\n");
 120 #endif
 121         fprintf(ofp, "    --syscall              System call event\n");
 122         fprintf(ofp, "\n");
 123 }
 124
 125 /*
 126  * Parse probe options.
 127  */
 128 static int parse_probe_opts(struct lttng_event *ev, char *opt)
 129 {
 130         int ret;
 131         char s_hex[19];
 132         char name[LTTNG_SYMBOL_NAME_LEN];
 133
 134         if (opt == NULL) {
 135                 ret = -1;
 136                 goto end;
 137         }
 138
 139         /* Check for symbol+offset */
 140         ret = sscanf(opt, "%[^'+']+%s", name, s_hex);
 141         if (ret == 2) {
 142                 strncpy(ev->attr.probe.symbol_name, name, LTTNG_SYMBOL_NAME_LEN);
 143                 ev->attr.probe.symbol_name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 144                 DBG("probe symbol %s", ev->attr.probe.symbol_name);
 145                 if (strlen(s_hex) == 0) {
 146                         ERR("Invalid probe offset %s", s_hex);
 147                         ret = -1;
 148                         goto end;
 149                 }
 150                 ev->attr.probe.offset = strtoul(s_hex, NULL, 0);
 151                 DBG("probe offset %" PRIu64, ev->attr.probe.offset);
 152                 ev->attr.probe.addr = 0;
 153                 goto end;
 154         }
 155
 156         /* Check for symbol */
 157         if (isalpha(name[0])) {
 158                 ret = sscanf(opt, "%s", name);
 159                 if (ret == 1) {
 160                         strncpy(ev->attr.probe.symbol_name, name, LTTNG_SYMBOL_NAME_LEN);
 161                         ev->attr.probe.symbol_name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 162                         DBG("probe symbol %s", ev->attr.probe.symbol_name);
 163                         ev->attr.probe.offset = 0;
 164                         DBG("probe offset %" PRIu64, ev->attr.probe.offset);
 165                         ev->attr.probe.addr = 0;
 166                         goto end;
 167                 }
 168         }
 169
 170         /* Check for address */
 171         ret = sscanf(opt, "%s", s_hex);
 172         if (ret > 0) {
 173                 if (strlen(s_hex) == 0) {
 174                         ERR("Invalid probe address %s", s_hex);
 175                         ret = -1;
 176                         goto end;
 177                 }
 178                 ev->attr.probe.addr = strtoul(s_hex, NULL, 0);
 179                 DBG("probe addr %" PRIu64, ev->attr.probe.addr);
 180                 ev->attr.probe.offset = 0;
 181                 memset(ev->attr.probe.symbol_name, 0, LTTNG_SYMBOL_NAME_LEN);
 182                 goto end;
 183         }
 184
 185         /* No match */
 186         ret = -1;
 187
 188 end:
 189         return ret;
 190 }
 191
 192 /*
 193  * Enabling event using the lttng API.
 194  */
 195 static int enable_events(char *session_name)
 196 {
 197         int err, ret = CMD_SUCCESS;
 198         char *event_name, *channel_name = NULL;
 199         struct lttng_event ev;
 200         struct lttng_domain dom;
 201
 202         if (opt_channel_name == NULL) {
 203                 err = asprintf(&channel_name, DEFAULT_CHANNEL_NAME);
 204                 if (err < 0) {
 205                         ret = CMD_FATAL;
 206                         goto error;
 207                 }
 208         } else {
 209                 channel_name = opt_channel_name;
 210         }
 211
 212         if (opt_kernel && opt_userspace) {
 213                 ERR("Can't use -k/--kernel and -u/--userspace together");
 214                 ret = CMD_FATAL;
 215                 goto error;
 216         }
 217
 218         /* Create lttng domain */
 219         if (opt_kernel) {
 220                 dom.type = LTTNG_DOMAIN_KERNEL;
 221         } else if (opt_pid != 0) {
 222                 dom.type = LTTNG_DOMAIN_UST_PID;
 223                 dom.attr.pid = opt_pid;
 224                 DBG("PID %d set to lttng handle", opt_pid);
 225         } else if (opt_userspace && opt_cmd_name == NULL) {
 226                 dom.type = LTTNG_DOMAIN_UST;
 227         } else if (opt_userspace && opt_cmd_name != NULL) {
 228                 dom.type = LTTNG_DOMAIN_UST_EXEC_NAME;
 229                 strncpy(dom.attr.exec_name, opt_cmd_name, NAME_MAX);
 230         } else {
 231                 ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
 232                 ret = CMD_NOT_IMPLEMENTED;
 233                 goto error;
 234         }
 235
 236         handle = lttng_create_handle(session_name, &dom);
 237         if (handle == NULL) {
 238                 ret = -1;
 239                 goto error;
 240         }
 241
 242         if (opt_enable_all) {
 243                 /* Default setup for enable all */
 244
 245                 if (opt_kernel) {
 246                         ev.type = opt_event_type;
 247                         ev.name[0] = '\0';
 248                 } else {
 249                         ev.type = LTTNG_EVENT_TRACEPOINT;
 250                         strcpy(ev.name, "*");
 251                 }
 252
 253                 ret = lttng_enable_event(handle, &ev, channel_name);
 254                 if (ret < 0) {
 255                         goto error;
 256                 }
 257
 258                 switch (opt_event_type) {
 259                 case LTTNG_EVENT_TRACEPOINT:
 260                         MSG("All %s tracepoints are enabled in channel %s",
 261                                 opt_kernel ? "kernel" : "UST", channel_name);
 262                         break;
 263                 case LTTNG_EVENT_SYSCALL:
 264                         if (opt_kernel) {
 265                                 MSG("All kernel system calls are enabled in channel %s",
 266                                                 channel_name);
 267                         }
 268                         break;
 269                 case LTTNG_EVENT_ALL:
 270                         MSG("All %s events are enabled in channel %s",
 271                                 opt_kernel ? "kernel" : "UST", channel_name);
 272                         break;
 273                 default:
 274                         /*
 275                          * We should not be here since lttng_enable_event should have
 276                          * failed on the event type.
 277                          */
 278                         goto error;
 279                 }
 280                 goto end;
 281         }
 282
 283         /* Strip event list */
 284         event_name = strtok(opt_event_list, ",");
 285         while (event_name != NULL) {
 286                 /* Copy name and type of the event */
 287                 strncpy(ev.name, event_name, LTTNG_SYMBOL_NAME_LEN);
 288                 ev.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 289                 ev.type = opt_event_type;
 290
 291                 /* Kernel tracer action */
 292                 if (opt_kernel) {
 293                         DBG("Enabling kernel event %s for channel %s",
 294                                         event_name, channel_name);
 295
 296                         switch (opt_event_type) {
 297                         case LTTNG_EVENT_ALL:   /* Default behavior is tracepoint */
 298                                 ev.type = LTTNG_EVENT_TRACEPOINT;
 299                                 /* Fall-through */
 300                         case LTTNG_EVENT_TRACEPOINT:
 301                                 break;
 302                         case LTTNG_EVENT_PROBE:
 303                                 ret = parse_probe_opts(&ev, opt_probe);
 304                                 if (ret < 0) {
 305                                         ERR("Unable to parse probe options");
 306                                         ret = 0;
 307                                         goto error;
 308                                 }
 309                                 break;
 310                         case LTTNG_EVENT_FUNCTION:
 311                                 ret = parse_probe_opts(&ev, opt_function);
 312                                 if (ret < 0) {
 313                                         ERR("Unable to parse function probe options");
 314                                         ret = 0;
 315                                         goto error;
 316                                 }
 317                                 break;
 318                         case LTTNG_EVENT_FUNCTION_ENTRY:
 319                                 strncpy(ev.attr.ftrace.symbol_name, opt_function_entry_symbol,
 320                                                 LTTNG_SYMBOL_NAME_LEN);
 321                                 ev.attr.ftrace.symbol_name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 322                                 break;
 323                         case LTTNG_EVENT_SYSCALL:
 324                                 MSG("per-syscall selection not supported yet. Use \"-a\" "
 325                                                 "for all syscalls.");
 326                         default:
 327                                 ret = CMD_NOT_IMPLEMENTED;
 328                                 goto error;
 329                         }
 330                 } else if (opt_userspace) {             /* User-space tracer action */
 331                         if (opt_cmd_name != NULL || opt_pid) {
 332                                 MSG("Only supporting tracing all UST processes (-u) for now.");
 333                                 ret = CMD_NOT_IMPLEMENTED;
 334                                 goto error;
 335                         }
 336
 337                         DBG("Enabling UST event %s for channel %s", event_name,
 338                                         channel_name);
 339
 340                         switch (opt_event_type) {
 341                         case LTTNG_EVENT_ALL:   /* Default behavior is tracepoint */
 342                                 /* Fall-through */
 343                         case LTTNG_EVENT_TRACEPOINT:
 344                                 /* Copy name and type of the event */
 345                                 ev.type = LTTNG_EVENT_TRACEPOINT;
 346                                 strncpy(ev.name, event_name, LTTNG_SYMBOL_NAME_LEN);
 347                                 ev.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 348                                 break;
 349                         case LTTNG_EVENT_TRACEPOINT_LOGLEVEL:
 350                                 /* Copy name and type of the event */
 351                                 ev.type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
 352                                 strncpy(ev.name, event_name, LTTNG_SYMBOL_NAME_LEN);
 353                                 ev.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 354                                 break;
 355                         case LTTNG_EVENT_PROBE:
 356                         case LTTNG_EVENT_FUNCTION:
 357                         case LTTNG_EVENT_FUNCTION_ENTRY:
 358                         case LTTNG_EVENT_SYSCALL:
 359                         default:
 360                                 ret = CMD_NOT_IMPLEMENTED;
 361                                 goto error;
 362                         }
 363                 } else {
 364                         ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
 365                         goto error;
 366                 }
 367
 368                 ret = lttng_enable_event(handle, &ev, channel_name);
 369                 if (ret == 0) {
 370                         MSG("%s event %s created in channel %s",
 371                                         opt_kernel ? "kernel": "UST", event_name, channel_name);
 372                 }
 373
 374                 /* Next event */
 375                 event_name = strtok(NULL, ",");
 376         }
 377
 378 end:
 379 error:
 380         if (opt_channel_name == NULL) {
 381                 free(channel_name);
 382         }
 383         lttng_destroy_handle(handle);
 384
 385         return ret;
 386 }
 387
 388 /*
 389  * Add event to trace session
 390  */
 391 int cmd_enable_events(int argc, const char **argv)
 392 {
 393         int opt, ret;
 394         static poptContext pc;
 395         char *session_name = NULL;
 396
 397         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 398         poptReadDefaultConfig(pc, 0);
 399
 400         /* Default event type */
 401         opt_event_type = LTTNG_EVENT_ALL;
 402
 403         while ((opt = poptGetNextOpt(pc)) != -1) {
 404                 switch (opt) {
 405                 case OPT_HELP:
 406                         usage(stderr);
 407                         ret = CMD_SUCCESS;
 408                         goto end;
 409                 case OPT_TRACEPOINT:
 410                         opt_event_type = LTTNG_EVENT_TRACEPOINT;
 411                         break;
 412                 case OPT_PROBE:
 413                         opt_event_type = LTTNG_EVENT_PROBE;
 414                         break;
 415                 case OPT_FUNCTION:
 416                         opt_event_type = LTTNG_EVENT_FUNCTION;
 417                         break;
 418                 case OPT_FUNCTION_ENTRY:
 419                         opt_event_type = LTTNG_EVENT_FUNCTION_ENTRY;
 420                         break;
 421                 case OPT_SYSCALL:
 422                         opt_event_type = LTTNG_EVENT_SYSCALL;
 423                         break;
 424                 case OPT_USERSPACE:
 425                         opt_userspace = 1;
 426                         break;
 427                 case OPT_TRACEPOINT_LOGLEVEL:
 428                         opt_event_type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
 429                         break;
 430                 default:
 431                         usage(stderr);
 432                         ret = CMD_UNDEFINED;
 433                         goto end;
 434                 }
 435         }
 436
 437         opt_event_list = (char*) poptGetArg(pc);
 438         if (opt_event_list == NULL && opt_enable_all == 0) {
 439                 ERR("Missing event name(s).\n");
 440                 usage(stderr);
 441                 ret = CMD_SUCCESS;
 442                 goto end;
 443         }
 444
 445         if (!opt_session_name) {
 446                 session_name = get_session_name();
 447                 if (session_name == NULL) {
 448                         ret = -1;
 449                         goto end;
 450                 }
 451         } else {
 452                 session_name = opt_session_name;
 453         }
 454
 455         ret = enable_events(session_name);
 456
 457 end:
 458         if (opt_session_name == NULL) {
 459                 free(session_name);
 460         }
 461
 462         return ret;
 463 }