liblttng-ust/lttng-filter.c

   1 /*
   2  * lttng-filter.c
   3  *
   4  * LTTng UST filter code.
   5  *
   6  * Copyright (C) 2010-2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  24  * SOFTWARE.
  25  */
  26
  27 #define _LGPL_SOURCE
  28 #include <urcu/rculist.h>
  29 #include "lttng-filter.h"
  30
  31 static const char *opnames[] = {
  32         [ FILTER_OP_UNKNOWN ] = "UNKNOWN",
  33
  34         [ FILTER_OP_RETURN ] = "RETURN",
  35
  36         /* binary */
  37         [ FILTER_OP_MUL ] = "MUL",
  38         [ FILTER_OP_DIV ] = "DIV",
  39         [ FILTER_OP_MOD ] = "MOD",
  40         [ FILTER_OP_PLUS ] = "PLUS",
  41         [ FILTER_OP_MINUS ] = "MINUS",
  42         [ FILTER_OP_BIT_RSHIFT ] = "BIT_RSHIFT",
  43         [ FILTER_OP_BIT_LSHIFT ] = "BIT_LSHIFT",
  44         [ FILTER_OP_BIT_AND ] = "BIT_AND",
  45         [ FILTER_OP_BIT_OR ] = "BIT_OR",
  46         [ FILTER_OP_BIT_XOR ] = "BIT_XOR",
  47
  48         /* binary comparators */
  49         [ FILTER_OP_EQ ] = "EQ",
  50         [ FILTER_OP_NE ] = "NE",
  51         [ FILTER_OP_GT ] = "GT",
  52         [ FILTER_OP_LT ] = "LT",
  53         [ FILTER_OP_GE ] = "GE",
  54         [ FILTER_OP_LE ] = "LE",
  55
  56         /* string binary comparators */
  57         [ FILTER_OP_EQ_STRING ] = "EQ_STRING",
  58         [ FILTER_OP_NE_STRING ] = "NE_STRING",
  59         [ FILTER_OP_GT_STRING ] = "GT_STRING",
  60         [ FILTER_OP_LT_STRING ] = "LT_STRING",
  61         [ FILTER_OP_GE_STRING ] = "GE_STRING",
  62         [ FILTER_OP_LE_STRING ] = "LE_STRING",
  63
  64         /* s64 binary comparators */
  65         [ FILTER_OP_EQ_S64 ] = "EQ_S64",
  66         [ FILTER_OP_NE_S64 ] = "NE_S64",
  67         [ FILTER_OP_GT_S64 ] = "GT_S64",
  68         [ FILTER_OP_LT_S64 ] = "LT_S64",
  69         [ FILTER_OP_GE_S64 ] = "GE_S64",
  70         [ FILTER_OP_LE_S64 ] = "LE_S64",
  71
  72         /* double binary comparators */
  73         [ FILTER_OP_EQ_DOUBLE ] = "EQ_DOUBLE",
  74         [ FILTER_OP_NE_DOUBLE ] = "NE_DOUBLE",
  75         [ FILTER_OP_GT_DOUBLE ] = "GT_DOUBLE",
  76         [ FILTER_OP_LT_DOUBLE ] = "LT_DOUBLE",
  77         [ FILTER_OP_GE_DOUBLE ] = "GE_DOUBLE",
  78         [ FILTER_OP_LE_DOUBLE ] = "LE_DOUBLE",
  79
  80         /* Mixed S64-double binary comparators */
  81         [ FILTER_OP_EQ_DOUBLE_S64 ] = "EQ_DOUBLE_S64",
  82         [ FILTER_OP_NE_DOUBLE_S64 ] = "NE_DOUBLE_S64",
  83         [ FILTER_OP_GT_DOUBLE_S64 ] = "GT_DOUBLE_S64",
  84         [ FILTER_OP_LT_DOUBLE_S64 ] = "LT_DOUBLE_S64",
  85         [ FILTER_OP_GE_DOUBLE_S64 ] = "GE_DOUBLE_S64",
  86         [ FILTER_OP_LE_DOUBLE_S64 ] = "LE_DOUBLE_S64",
  87
  88         [ FILTER_OP_EQ_S64_DOUBLE ] = "EQ_S64_DOUBLE",
  89         [ FILTER_OP_NE_S64_DOUBLE ] = "NE_S64_DOUBLE",
  90         [ FILTER_OP_GT_S64_DOUBLE ] = "GT_S64_DOUBLE",
  91         [ FILTER_OP_LT_S64_DOUBLE ] = "LT_S64_DOUBLE",
  92         [ FILTER_OP_GE_S64_DOUBLE ] = "GE_S64_DOUBLE",
  93         [ FILTER_OP_LE_S64_DOUBLE ] = "LE_S64_DOUBLE",
  94
  95         /* unary */
  96         [ FILTER_OP_UNARY_PLUS ] = "UNARY_PLUS",
  97         [ FILTER_OP_UNARY_MINUS ] = "UNARY_MINUS",
  98         [ FILTER_OP_UNARY_NOT ] = "UNARY_NOT",
  99         [ FILTER_OP_UNARY_PLUS_S64 ] = "UNARY_PLUS_S64",
 100         [ FILTER_OP_UNARY_MINUS_S64 ] = "UNARY_MINUS_S64",
 101         [ FILTER_OP_UNARY_NOT_S64 ] = "UNARY_NOT_S64",
 102         [ FILTER_OP_UNARY_PLUS_DOUBLE ] = "UNARY_PLUS_DOUBLE",
 103         [ FILTER_OP_UNARY_MINUS_DOUBLE ] = "UNARY_MINUS_DOUBLE",
 104         [ FILTER_OP_UNARY_NOT_DOUBLE ] = "UNARY_NOT_DOUBLE",
 105
 106         /* logical */
 107         [ FILTER_OP_AND ] = "AND",
 108         [ FILTER_OP_OR ] = "OR",
 109
 110         /* load field ref */
 111         [ FILTER_OP_LOAD_FIELD_REF ] = "LOAD_FIELD_REF",
 112         [ FILTER_OP_LOAD_FIELD_REF_STRING ] = "LOAD_FIELD_REF_STRING",
 113         [ FILTER_OP_LOAD_FIELD_REF_SEQUENCE ] = "LOAD_FIELD_REF_SEQUENCE",
 114         [ FILTER_OP_LOAD_FIELD_REF_S64 ] = "LOAD_FIELD_REF_S64",
 115         [ FILTER_OP_LOAD_FIELD_REF_DOUBLE ] = "LOAD_FIELD_REF_DOUBLE",
 116
 117         /* load from immediate operand */
 118         [ FILTER_OP_LOAD_STRING ] = "LOAD_STRING",
 119         [ FILTER_OP_LOAD_S64 ] = "LOAD_S64",
 120         [ FILTER_OP_LOAD_DOUBLE ] = "LOAD_DOUBLE",
 121
 122         /* cast */
 123         [ FILTER_OP_CAST_TO_S64 ] = "CAST_TO_S64",
 124         [ FILTER_OP_CAST_DOUBLE_TO_S64 ] = "CAST_DOUBLE_TO_S64",
 125         [ FILTER_OP_CAST_NOP ] = "CAST_NOP",
 126
 127         /* get context ref */
 128         [ FILTER_OP_GET_CONTEXT_REF ] = "GET_CONTEXT_REF",
 129         [ FILTER_OP_GET_CONTEXT_REF_STRING ] = "GET_CONTEXT_REF_STRING",
 130         [ FILTER_OP_GET_CONTEXT_REF_S64 ] = "GET_CONTEXT_REF_S64",
 131         [ FILTER_OP_GET_CONTEXT_REF_DOUBLE ] = "GET_CONTEXT_REF_DOUBLE",
 132
 133         /* load userspace field ref */
 134         [ FILTER_OP_LOAD_FIELD_REF_USER_STRING ] = "LOAD_FIELD_REF_USER_STRING",
 135         [ FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE ] = "LOAD_FIELD_REF_USER_SEQUENCE",
 136
 137         /*
 138          * load immediate star globbing pattern (literal string)
 139          * from immediate.
 140          */
 141         [ FILTER_OP_LOAD_STAR_GLOB_STRING ] = "LOAD_STAR_GLOB_STRING",
 142
 143         /* globbing pattern binary operator: apply to */
 144         [ FILTER_OP_EQ_STAR_GLOB_STRING ] = "EQ_STAR_GLOB_STRING",
 145         [ FILTER_OP_NE_STAR_GLOB_STRING ] = "NE_STAR_GLOB_STRING",
 146
 147         /*
 148          * Instructions for recursive traversal through composed types.
 149          */
 150         [ FILTER_OP_GET_CONTEXT_ROOT ] = "GET_CONTEXT_ROOT",
 151         [ FILTER_OP_GET_APP_CONTEXT_ROOT ] = "GET_APP_CONTEXT_ROOT",
 152         [ FILTER_OP_GET_PAYLOAD_ROOT ] = "GET_PAYLOAD_ROOT",
 153
 154         [ FILTER_OP_GET_SYMBOL ] = "GET_SYMBOL",
 155         [ FILTER_OP_GET_SYMBOL_FIELD ] = "GET_SYMBOL_FIELD",
 156         [ FILTER_OP_GET_INDEX_U16 ] = "GET_INDEX_U16",
 157         [ FILTER_OP_GET_INDEX_U64 ] = "GET_INDEX_U64",
 158
 159         [ FILTER_OP_LOAD_FIELD ] = "LOAD_FIELD",
 160         [ FILTER_OP_LOAD_FIELD_S8 ] = "LOAD_FIELD_S8",
 161         [ FILTER_OP_LOAD_FIELD_S16 ] = "LOAD_FIELD_S16",
 162         [ FILTER_OP_LOAD_FIELD_S32 ] = "LOAD_FIELD_S32",
 163         [ FILTER_OP_LOAD_FIELD_S64 ] = "LOAD_FIELD_S64",
 164         [ FILTER_OP_LOAD_FIELD_U8 ] = "LOAD_FIELD_U8",
 165         [ FILTER_OP_LOAD_FIELD_U16 ] = "LOAD_FIELD_U16",
 166         [ FILTER_OP_LOAD_FIELD_U32 ] = "LOAD_FIELD_U32",
 167         [ FILTER_OP_LOAD_FIELD_U64 ] = "LOAD_FIELD_U64",
 168         [ FILTER_OP_LOAD_FIELD_STRING ] = "LOAD_FIELD_STRING",
 169         [ FILTER_OP_LOAD_FIELD_SEQUENCE ] = "LOAD_FIELD_SEQUENCE",
 170         [ FILTER_OP_LOAD_FIELD_DOUBLE ] = "LOAD_FIELD_DOUBLE",
 171
 172         [ FILTER_OP_UNARY_BIT_NOT ] = "UNARY_BIT_NOT",
 173
 174         [ FILTER_OP_RETURN_S64 ] = "RETURN_S64",
 175 };
 176
 177 const char *print_op(enum filter_op op)
 178 {
 179         if (op >= NR_FILTER_OPS)
 180                 return "UNKNOWN";
 181         else
 182                 return opnames[op];
 183 }
 184
 185 static
 186 int apply_field_reloc(struct lttng_event *event,
 187                 struct bytecode_runtime *runtime,
 188                 uint32_t runtime_len,
 189                 uint32_t reloc_offset,
 190                 const char *field_name,
 191                 enum filter_op filter_op)
 192 {
 193         const struct lttng_event_desc *desc;
 194         const struct lttng_event_field *fields, *field = NULL;
 195         unsigned int nr_fields, i;
 196         struct load_op *op;
 197         uint32_t field_offset = 0;
 198
 199         dbg_printf("Apply field reloc: %u %s\n", reloc_offset, field_name);
 200
 201         /* Lookup event by name */
 202         desc = event->desc;
 203         if (!desc)
 204                 return -EINVAL;
 205         fields = desc->fields;
 206         if (!fields)
 207                 return -EINVAL;
 208         nr_fields = desc->nr_fields;
 209         for (i = 0; i < nr_fields; i++) {
 210                 if (!strcmp(fields[i].name, field_name)) {
 211                         field = &fields[i];
 212                         break;
 213                 }
 214                 /* compute field offset */
 215                 switch (fields[i].type.atype) {
 216                 case atype_integer:
 217                 case atype_enum:
 218                         field_offset += sizeof(int64_t);
 219                         break;
 220                 case atype_array:
 221                 case atype_sequence:
 222                         field_offset += sizeof(unsigned long);
 223                         field_offset += sizeof(void *);
 224                         break;
 225                 case atype_string:
 226                         field_offset += sizeof(void *);
 227                         break;
 228                 case atype_float:
 229                         field_offset += sizeof(double);
 230                         break;
 231                 default:
 232                         return -EINVAL;
 233                 }
 234         }
 235         if (!field)
 236                 return -EINVAL;
 237
 238         /* Check if field offset is too large for 16-bit offset */
 239         if (field_offset > FILTER_BYTECODE_MAX_LEN - 1)
 240                 return -EINVAL;
 241
 242         /* set type */
 243         op = (struct load_op *) &runtime->code[reloc_offset];
 244
 245         switch (filter_op) {
 246         case FILTER_OP_LOAD_FIELD_REF:
 247         {
 248                 struct field_ref *field_ref;
 249
 250                 field_ref = (struct field_ref *) op->data;
 251                 switch (field->type.atype) {
 252                 case atype_integer:
 253                 case atype_enum:
 254                         op->op = FILTER_OP_LOAD_FIELD_REF_S64;
 255                         break;
 256                 case atype_array:
 257                 case atype_sequence:
 258                         op->op = FILTER_OP_LOAD_FIELD_REF_SEQUENCE;
 259                         break;
 260                 case atype_string:
 261                         op->op = FILTER_OP_LOAD_FIELD_REF_STRING;
 262                         break;
 263                 case atype_float:
 264                         op->op = FILTER_OP_LOAD_FIELD_REF_DOUBLE;
 265                         break;
 266                 default:
 267                         return -EINVAL;
 268                 }
 269                 /* set offset */
 270                 field_ref->offset = (uint16_t) field_offset;
 271                 break;
 272         }
 273         default:
 274                 return -EINVAL;
 275         }
 276         return 0;
 277 }
 278
 279 static
 280 int apply_context_reloc(struct lttng_event *event,
 281                 struct bytecode_runtime *runtime,
 282                 uint32_t runtime_len,
 283                 uint32_t reloc_offset,
 284                 const char *context_name,
 285                 enum filter_op filter_op)
 286 {
 287         struct load_op *op;
 288         struct lttng_ctx_field *ctx_field;
 289         int idx;
 290         struct lttng_session *session = runtime->p.session;
 291
 292         dbg_printf("Apply context reloc: %u %s\n", reloc_offset, context_name);
 293
 294         /* Get context index */
 295         idx = lttng_get_context_index(session->ctx, context_name);
 296         if (idx < 0) {
 297                 if (lttng_context_is_app(context_name)) {
 298                         int ret;
 299
 300                         ret = lttng_ust_add_app_context_to_ctx_rcu(context_name,
 301                                         &session->ctx);
 302                         if (ret)
 303                                 return ret;
 304                         idx = lttng_get_context_index(session->ctx,
 305                                 context_name);
 306                         if (idx < 0)
 307                                 return -ENOENT;
 308                 } else {
 309                         return -ENOENT;
 310                 }
 311         }
 312         /* Check if idx is too large for 16-bit offset */
 313         if (idx > FILTER_BYTECODE_MAX_LEN - 1)
 314                 return -EINVAL;
 315
 316         /* Get context return type */
 317         ctx_field = &session->ctx->fields[idx];
 318         op = (struct load_op *) &runtime->code[reloc_offset];
 319
 320         switch (filter_op) {
 321         case FILTER_OP_GET_CONTEXT_REF:
 322         {
 323                 struct field_ref *field_ref;
 324
 325                 field_ref = (struct field_ref *) op->data;
 326                 switch (ctx_field->event_field.type.atype) {
 327                 case atype_integer:
 328                 case atype_enum:
 329                         op->op = FILTER_OP_GET_CONTEXT_REF_S64;
 330                         break;
 331                         /* Sequence and array supported as string */
 332                 case atype_string:
 333                 case atype_array:
 334                 case atype_sequence:
 335                         op->op = FILTER_OP_GET_CONTEXT_REF_STRING;
 336                         break;
 337                 case atype_float:
 338                         op->op = FILTER_OP_GET_CONTEXT_REF_DOUBLE;
 339                         break;
 340                 case atype_dynamic:
 341                         op->op = FILTER_OP_GET_CONTEXT_REF;
 342                         break;
 343                 default:
 344                         return -EINVAL;
 345                 }
 346                 /* set offset to context index within channel contexts */
 347                 field_ref->offset = (uint16_t) idx;
 348                 break;
 349         }
 350         default:
 351                 return -EINVAL;
 352         }
 353         return 0;
 354 }
 355
 356 static
 357 int apply_reloc(struct lttng_event *event,
 358                 struct bytecode_runtime *runtime,
 359                 uint32_t runtime_len,
 360                 uint32_t reloc_offset,
 361                 const char *name)
 362 {
 363         struct load_op *op;
 364
 365         dbg_printf("Apply reloc: %u %s\n", reloc_offset, name);
 366
 367         /* Ensure that the reloc is within the code */
 368         if (runtime_len - reloc_offset < sizeof(uint16_t))
 369                 return -EINVAL;
 370
 371         op = (struct load_op *) &runtime->code[reloc_offset];
 372         switch (op->op) {
 373         case FILTER_OP_LOAD_FIELD_REF:
 374                 return apply_field_reloc(event, runtime, runtime_len,
 375                         reloc_offset, name, op->op);
 376         case FILTER_OP_GET_CONTEXT_REF:
 377                 return apply_context_reloc(event, runtime, runtime_len,
 378                         reloc_offset, name, op->op);
 379         case FILTER_OP_GET_SYMBOL:
 380         case FILTER_OP_GET_SYMBOL_FIELD:
 381                 /*
 382                  * Will be handled by load specialize phase or
 383                  * dynamically by interpreter.
 384                  */
 385                 return 0;
 386         default:
 387                 ERR("Unknown reloc op type %u\n", op->op);
 388                 return -EINVAL;
 389         }
 390         return 0;
 391 }
 392
 393 static
 394 int bytecode_is_linked(struct lttng_ust_filter_bytecode_node *filter_bytecode,
 395                 struct lttng_event *event)
 396 {
 397         struct lttng_bytecode_runtime *bc_runtime;
 398
 399         cds_list_for_each_entry(bc_runtime,
 400                         &event->bytecode_runtime_head, node) {
 401                 if (bc_runtime->bc == filter_bytecode)
 402                         return 1;
 403         }
 404         return 0;
 405 }
 406
 407 /*
 408  * Take a bytecode with reloc table and link it to an event to create a
 409  * bytecode runtime.
 410  */
 411 static
 412 int _lttng_filter_event_link_bytecode(struct lttng_event *event,
 413                 struct lttng_ust_filter_bytecode_node *filter_bytecode,
 414                 struct cds_list_head *insert_loc)
 415 {
 416         int ret, offset, next_offset;
 417         struct bytecode_runtime *runtime = NULL;
 418         size_t runtime_alloc_len;
 419
 420         if (!filter_bytecode)
 421                 return 0;
 422         /* Bytecode already linked */
 423         if (bytecode_is_linked(filter_bytecode, event))
 424                 return 0;
 425
 426         dbg_printf("Linking...\n");
 427
 428         /* We don't need the reloc table in the runtime */
 429         runtime_alloc_len = sizeof(*runtime) + filter_bytecode->bc.reloc_offset;
 430         runtime = zmalloc(runtime_alloc_len);
 431         if (!runtime) {
 432                 ret = -ENOMEM;
 433                 goto alloc_error;
 434         }
 435         runtime->p.bc = filter_bytecode;
 436         runtime->p.session = event->chan->session;
 437         runtime->p.event = event;
 438         runtime->len = filter_bytecode->bc.reloc_offset;
 439         /* copy original bytecode */
 440         memcpy(runtime->code, filter_bytecode->bc.data, runtime->len);
 441         /*
 442          * apply relocs. Those are a uint16_t (offset in bytecode)
 443          * followed by a string (field name).
 444          */
 445         for (offset = filter_bytecode->bc.reloc_offset;
 446                         offset < filter_bytecode->bc.len;
 447                         offset = next_offset) {
 448                 uint16_t reloc_offset =
 449                         *(uint16_t *) &filter_bytecode->bc.data[offset];
 450                 const char *name =
 451                         (const char *) &filter_bytecode->bc.data[offset + sizeof(uint16_t)];
 452
 453                 ret = apply_reloc(event, runtime, runtime->len, reloc_offset, name);
 454                 if (ret) {
 455                         goto link_error;
 456                 }
 457                 next_offset = offset + sizeof(uint16_t) + strlen(name) + 1;
 458         }
 459         /* Validate bytecode */
 460         ret = lttng_filter_validate_bytecode(runtime);
 461         if (ret) {
 462                 goto link_error;
 463         }
 464         /* Specialize bytecode */
 465         ret = lttng_filter_specialize_bytecode(event, runtime);
 466         if (ret) {
 467                 goto link_error;
 468         }
 469         runtime->p.filter = lttng_filter_interpret_bytecode;
 470         runtime->p.link_failed = 0;
 471         cds_list_add_rcu(&runtime->p.node, insert_loc);
 472         dbg_printf("Linking successful.\n");
 473         return 0;
 474
 475 link_error:
 476         runtime->p.filter = lttng_filter_false;
 477         runtime->p.link_failed = 1;
 478         cds_list_add_rcu(&runtime->p.node, insert_loc);
 479 alloc_error:
 480         dbg_printf("Linking failed.\n");
 481         return ret;
 482 }
 483
 484 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime)
 485 {
 486         struct lttng_ust_filter_bytecode_node *bc = runtime->bc;
 487
 488         if (!bc->enabler->enabled || runtime->link_failed)
 489                 runtime->filter = lttng_filter_false;
 490         else
 491                 runtime->filter = lttng_filter_interpret_bytecode;
 492 }
 493
 494 /*
 495  * Link bytecode for all enablers referenced by an event.
 496  */
 497 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 498                 struct lttng_enabler *enabler)
 499 {
 500         struct lttng_ust_filter_bytecode_node *bc;
 501         struct lttng_bytecode_runtime *runtime;
 502
 503         /* Can only be called for events with desc attached */
 504         assert(event->desc);
 505
 506         /* Link each bytecode. */
 507         cds_list_for_each_entry(bc, &enabler->filter_bytecode_head, node) {
 508                 int found = 0, ret;
 509                 struct cds_list_head *insert_loc;
 510
 511                 cds_list_for_each_entry(runtime,
 512                                 &event->bytecode_runtime_head, node) {
 513                         if (runtime->bc == bc) {
 514                                 found = 1;
 515                                 break;
 516                         }
 517                 }
 518                 /* Skip bytecode already linked */
 519                 if (found)
 520                         continue;
 521
 522                 /*
 523                  * Insert at specified priority (seqnum) in increasing
 524                  * order.
 525                  */
 526                 cds_list_for_each_entry_reverse(runtime,
 527                                 &event->bytecode_runtime_head, node) {
 528                         if (runtime->bc->bc.seqnum < bc->bc.seqnum) {
 529                                 /* insert here */
 530                                 insert_loc = &runtime->node;
 531                                 goto add_within;
 532                         }
 533                 }
 534                 /* Add to head to list */
 535                 insert_loc = &event->bytecode_runtime_head;
 536         add_within:
 537                 dbg_printf("linking bytecode\n");
 538                 ret = _lttng_filter_event_link_bytecode(event, bc,
 539                                 insert_loc);
 540                 if (ret) {
 541                         dbg_printf("[lttng filter] warning: cannot link event bytecode\n");
 542                 }
 543         }
 544 }
 545
 546 /*
 547  * We own the filter_bytecode if we return success.
 548  */
 549 int lttng_filter_enabler_attach_bytecode(struct lttng_enabler *enabler,
 550                 struct lttng_ust_filter_bytecode_node *filter_bytecode)
 551 {
 552         cds_list_add(&filter_bytecode->node, &enabler->filter_bytecode_head);
 553         return 0;
 554 }
 555
 556 void lttng_free_enabler_filter_bytecode(struct lttng_enabler *enabler)
 557 {
 558         struct lttng_ust_filter_bytecode_node *filter_bytecode, *tmp;
 559
 560         cds_list_for_each_entry_safe(filter_bytecode, tmp,
 561                         &enabler->filter_bytecode_head, node) {
 562                 free(filter_bytecode);
 563         }
 564 }
 565
 566 void lttng_free_event_filter_runtime(struct lttng_event *event)
 567 {
 568         struct bytecode_runtime *runtime, *tmp;
 569
 570         cds_list_for_each_entry_safe(runtime, tmp,
 571                         &event->bytecode_runtime_head, p.node) {
 572                 free(runtime->data);
 573                 free(runtime);
 574         }
 575 }