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, "    --loglevel             Tracepoint loglevel\n");
 104         fprintf(ofp, "    --probe [addr | symbol | symbol+offset]\n");
 105         fprintf(ofp, "                           Dynamic probe.\n");
 106         fprintf(ofp, "                           Addr and offset can be octal (0NNN...),\n");
 107         fprintf(ofp, "                           decimal (NNN...) or hexadecimal (0xNNN...)\n");
 108         fprintf(ofp, "    --function [addr | symbol | symbol+offset]\n");
 109         fprintf(ofp, "                           Dynamic function entry/return probe.\n");
 110         fprintf(ofp, "                           Addr and offset can be octal (0NNN...),\n");
 111         fprintf(ofp, "                           decimal (NNN...) or hexadecimal (0xNNN...)\n");
 112 #if 0
 113         fprintf(ofp, "    --function:entry symbol\n");
 114         fprintf(ofp, "                           Function tracer event\n");
 115 #endif
 116         fprintf(ofp, "    --syscall              System call event\n");
 117         fprintf(ofp, "\n");
 118 }
 119
 120 /*
 121  * Parse probe options.
 122  */
 123 static int parse_probe_opts(struct lttng_event *ev, char *opt)
 124 {
 125         int ret;
 126         char s_hex[19];
 127         char name[LTTNG_SYMBOL_NAME_LEN];
 128
 129         if (opt == NULL) {
 130                 ret = -1;
 131                 goto end;
 132         }
 133
 134         /* Check for symbol+offset */
 135         ret = sscanf(opt, "%[^'+']+%s", name, s_hex);
 136         if (ret == 2) {
 137                 strncpy(ev->attr.probe.symbol_name, name, LTTNG_SYMBOL_NAME_LEN);
 138                 ev->attr.probe.symbol_name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 139                 DBG("probe symbol %s", ev->attr.probe.symbol_name);
 140                 if (strlen(s_hex) == 0) {
 141                         ERR("Invalid probe offset %s", s_hex);
 142                         ret = -1;
 143                         goto end;
 144                 }
 145                 ev->attr.probe.offset = strtoul(s_hex, NULL, 0);
 146                 DBG("probe offset %" PRIu64, ev->attr.probe.offset);
 147                 ev->attr.probe.addr = 0;
 148                 goto end;
 149         }
 150
 151         /* Check for symbol */
 152         if (isalpha(name[0])) {
 153                 ret = sscanf(opt, "%s", name);
 154                 if (ret == 1) {
 155                         strncpy(ev->attr.probe.symbol_name, name, LTTNG_SYMBOL_NAME_LEN);
 156                         ev->attr.probe.symbol_name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 157                         DBG("probe symbol %s", ev->attr.probe.symbol_name);
 158                         ev->attr.probe.offset = 0;
 159                         DBG("probe offset %" PRIu64, ev->attr.probe.offset);
 160                         ev->attr.probe.addr = 0;
 161                         goto end;
 162                 }
 163         }
 164
 165         /* Check for address */
 166         ret = sscanf(opt, "%s", s_hex);
 167         if (ret > 0) {
 168                 if (strlen(s_hex) == 0) {
 169                         ERR("Invalid probe address %s", s_hex);
 170                         ret = -1;
 171                         goto end;
 172                 }
 173                 ev->attr.probe.addr = strtoul(s_hex, NULL, 0);
 174                 DBG("probe addr %" PRIu64, ev->attr.probe.addr);
 175                 ev->attr.probe.offset = 0;
 176                 memset(ev->attr.probe.symbol_name, 0, LTTNG_SYMBOL_NAME_LEN);
 177                 goto end;
 178         }
 179
 180         /* No match */
 181         ret = -1;
 182
 183 end:
 184         return ret;
 185 }
 186
 187 /*
 188  * Enabling event using the lttng API.
 189  */
 190 static int enable_events(char *session_name)
 191 {
 192         int err, ret = CMD_SUCCESS;
 193         char *event_name, *channel_name = NULL;
 194         struct lttng_event ev;
 195         struct lttng_domain dom;
 196
 197         if (opt_channel_name == NULL) {
 198                 err = asprintf(&channel_name, DEFAULT_CHANNEL_NAME);
 199                 if (err < 0) {
 200                         ret = CMD_FATAL;
 201                         goto error;
 202                 }
 203         } else {
 204                 channel_name = opt_channel_name;
 205         }
 206
 207         if (opt_kernel && opt_userspace) {
 208                 ERR("Can't use -k/--kernel and -u/--userspace together");
 209                 ret = CMD_FATAL;
 210                 goto error;
 211         }
 212
 213         /* Create lttng domain */
 214         if (opt_kernel) {
 215                 dom.type = LTTNG_DOMAIN_KERNEL;
 216         } else if (opt_pid != 0) {
 217                 dom.type = LTTNG_DOMAIN_UST_PID;
 218                 dom.attr.pid = opt_pid;
 219                 DBG("PID %d set to lttng handle", opt_pid);
 220         } else if (opt_userspace && opt_cmd_name == NULL) {
 221                 dom.type = LTTNG_DOMAIN_UST;
 222         } else if (opt_userspace && opt_cmd_name != NULL) {
 223                 dom.type = LTTNG_DOMAIN_UST_EXEC_NAME;
 224                 strncpy(dom.attr.exec_name, opt_cmd_name, NAME_MAX);
 225         } else {
 226                 ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
 227                 ret = CMD_NOT_IMPLEMENTED;
 228                 goto error;
 229         }
 230
 231         handle = lttng_create_handle(session_name, &dom);
 232         if (handle == NULL) {
 233                 ret = -1;
 234                 goto error;
 235         }
 236
 237         if (opt_enable_all) {
 238                 /* Default setup for enable all */
 239                 ev.name[0] = '\0';
 240                 ev.type = opt_event_type;
 241
 242                 ret = lttng_enable_event(handle, &ev, channel_name);
 243                 if (ret < 0) {
 244                         goto error;
 245                 }
 246
 247                 switch (opt_event_type) {
 248                 case LTTNG_EVENT_TRACEPOINT:
 249                         MSG("All %s tracepoints are enabled in channel %s",
 250                                 opt_kernel ? "kernel" : "UST", channel_name);
 251                         break;
 252                 case LTTNG_EVENT_SYSCALL:
 253                         if (opt_kernel) {
 254                                 MSG("All kernel system calls are enabled in channel %s",
 255                                                 channel_name);
 256                         }
 257                         break;
 258                 case LTTNG_EVENT_ALL:
 259                         MSG("All %s events are enabled in channel %s",
 260                                 opt_kernel ? "kernel" : "UST", channel_name);
 261                         break;
 262                 default:
 263                         /*
 264                          * We should not be here since lttng_enable_event should have
 265                          * failed on the event type.
 266                          */
 267                         goto error;
 268                 }
 269                 goto end;
 270         }
 271
 272         /* Strip event list */
 273         event_name = strtok(opt_event_list, ",");
 274         while (event_name != NULL) {
 275                 /* Copy name and type of the event */
 276                 strncpy(ev.name, event_name, LTTNG_SYMBOL_NAME_LEN);
 277                 ev.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 278                 ev.type = opt_event_type;
 279
 280                 /* Kernel tracer action */
 281                 if (opt_kernel) {
 282                         DBG("Enabling kernel event %s for channel %s",
 283                                         event_name, channel_name);
 284
 285                         switch (opt_event_type) {
 286                         case LTTNG_EVENT_ALL:   /* Default behavior is tracepoint */
 287                                 ev.type = LTTNG_EVENT_TRACEPOINT;
 288                                 /* Fall-through */
 289                         case LTTNG_EVENT_TRACEPOINT:
 290                                 break;
 291                         case LTTNG_EVENT_PROBE:
 292                                 ret = parse_probe_opts(&ev, opt_probe);
 293                                 if (ret < 0) {
 294                                         ERR("Unable to parse probe options");
 295                                         ret = 0;
 296                                         goto error;
 297                                 }
 298                                 break;
 299                         case LTTNG_EVENT_FUNCTION:
 300                                 ret = parse_probe_opts(&ev, opt_function);
 301                                 if (ret < 0) {
 302                                         ERR("Unable to parse function probe options");
 303                                         ret = 0;
 304                                         goto error;
 305                                 }
 306                                 break;
 307                         case LTTNG_EVENT_FUNCTION_ENTRY:
 308                                 strncpy(ev.attr.ftrace.symbol_name, opt_function_entry_symbol,
 309                                                 LTTNG_SYMBOL_NAME_LEN);
 310                                 ev.attr.ftrace.symbol_name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 311                                 break;
 312                         case LTTNG_EVENT_SYSCALL:
 313                                 MSG("per-syscall selection not supported yet. Use \"-a\" "
 314                                                 "for all syscalls.");
 315                         default:
 316                                 ret = CMD_NOT_IMPLEMENTED;
 317                                 goto error;
 318                         }
 319                 } else if (opt_userspace) {             /* User-space tracer action */
 320                         if (opt_cmd_name != NULL || opt_pid) {
 321                                 MSG("Only supporting tracing all UST processes (-u) for now.");
 322                                 ret = CMD_NOT_IMPLEMENTED;
 323                                 goto error;
 324                         }
 325
 326                         DBG("Enabling UST event %s for channel %s", event_name,
 327                                         channel_name);
 328
 329                         switch (opt_event_type) {
 330                         case LTTNG_EVENT_ALL:   /* Default behavior is tracepoint */
 331                                 /* Fall-through */
 332                         case LTTNG_EVENT_TRACEPOINT:
 333                                 /* Copy name and type of the event */
 334                                 ev.type = LTTNG_EVENT_TRACEPOINT;
 335                                 strncpy(ev.name, event_name, LTTNG_SYMBOL_NAME_LEN);
 336                                 ev.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 337                                 break;
 338                         case LTTNG_EVENT_TRACEPOINT_LOGLEVEL:
 339                                 /* Copy name and type of the event */
 340                                 ev.type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
 341                                 strncpy(ev.name, event_name, LTTNG_SYMBOL_NAME_LEN);
 342                                 ev.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 343                                 break;
 344                         case LTTNG_EVENT_PROBE:
 345                         case LTTNG_EVENT_FUNCTION:
 346                         case LTTNG_EVENT_FUNCTION_ENTRY:
 347                         case LTTNG_EVENT_SYSCALL:
 348                         default:
 349                                 ret = CMD_NOT_IMPLEMENTED;
 350                                 goto error;
 351                         }
 352                 } else {
 353                         ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
 354                         goto error;
 355                 }
 356
 357                 ret = lttng_enable_event(handle, &ev, channel_name);
 358                 if (ret == 0) {
 359                         MSG("%s event %s created in channel %s",
 360                                         opt_kernel ? "kernel": "UST", event_name, channel_name);
 361                 }
 362
 363                 /* Next event */
 364                 event_name = strtok(NULL, ",");
 365         }
 366
 367 end:
 368 error:
 369         if (opt_channel_name == NULL) {
 370                 free(channel_name);
 371         }
 372         lttng_destroy_handle(handle);
 373
 374         return ret;
 375 }
 376
 377 /*
 378  * Add event to trace session
 379  */
 380 int cmd_enable_events(int argc, const char **argv)
 381 {
 382         int opt, ret;
 383         static poptContext pc;
 384         char *session_name = NULL;
 385
 386         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 387         poptReadDefaultConfig(pc, 0);
 388
 389         /* Default event type */
 390         opt_event_type = LTTNG_EVENT_ALL;
 391
 392         while ((opt = poptGetNextOpt(pc)) != -1) {
 393                 switch (opt) {
 394                 case OPT_HELP:
 395                         usage(stderr);
 396                         ret = CMD_SUCCESS;
 397                         goto end;
 398                 case OPT_TRACEPOINT:
 399                         opt_event_type = LTTNG_EVENT_TRACEPOINT;
 400                         break;
 401                 case OPT_PROBE:
 402                         opt_event_type = LTTNG_EVENT_PROBE;
 403                         break;
 404                 case OPT_FUNCTION:
 405                         opt_event_type = LTTNG_EVENT_FUNCTION;
 406                         break;
 407                 case OPT_FUNCTION_ENTRY:
 408                         opt_event_type = LTTNG_EVENT_FUNCTION_ENTRY;
 409                         break;
 410                 case OPT_SYSCALL:
 411                         opt_event_type = LTTNG_EVENT_SYSCALL;
 412                         break;
 413                 case OPT_USERSPACE:
 414                         opt_userspace = 1;
 415                         break;
 416                 case OPT_TRACEPOINT_LOGLEVEL:
 417                         opt_event_type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
 418                         break;
 419                 default:
 420                         usage(stderr);
 421                         ret = CMD_UNDEFINED;
 422                         goto end;
 423                 }
 424         }
 425
 426         opt_event_list = (char*) poptGetArg(pc);
 427         if (opt_event_list == NULL && opt_enable_all == 0) {
 428                 ERR("Missing event name(s).\n");
 429                 usage(stderr);
 430                 ret = CMD_SUCCESS;
 431                 goto end;
 432         }
 433
 434         if (!opt_session_name) {
 435                 session_name = get_session_name();
 436                 if (session_name == NULL) {
 437                         ret = -1;
 438                         goto end;
 439                 }
 440         } else {
 441                 session_name = opt_session_name;
 442         }
 443
 444         ret = enable_events(session_name);
 445
 446 end:
 447         if (opt_session_name == NULL) {
 448                 free(session_name);
 449         }
 450
 451         return ret;
 452 }