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