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_RSHIFT ] = "RSHIFT",
  43         [ FILTER_OP_LSHIFT ] = "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
 173 const char *print_op(enum filter_op op)
 174 {
 175         if (op >= NR_FILTER_OPS)
 176                 return "UNKNOWN";
 177         else
 178                 return opnames[op];
 179 }
 180
 181 static
 182 int apply_field_reloc(struct lttng_event *event,
 183                 struct bytecode_runtime *runtime,
 184                 uint32_t runtime_len,
 185                 uint32_t reloc_offset,
 186                 const char *field_name,
 187                 enum filter_op filter_op)
 188 {
 189         const struct lttng_event_desc *desc;
 190         const struct lttng_event_field *fields, *field = NULL;
 191         unsigned int nr_fields, i;
 192         struct load_op *op;
 193         uint32_t field_offset = 0;
 194
 195         dbg_printf("Apply field reloc: %u %s\n", reloc_offset, field_name);
 196
 197         /* Lookup event by name */
 198         desc = event->desc;
 199         if (!desc)
 200                 return -EINVAL;
 201         fields = desc->fields;
 202         if (!fields)
 203                 return -EINVAL;
 204         nr_fields = desc->nr_fields;
 205         for (i = 0; i < nr_fields; i++) {
 206                 if (!strcmp(fields[i].name, field_name)) {
 207                         field = &fields[i];
 208                         break;
 209                 }
 210                 /* compute field offset */
 211                 switch (fields[i].type.atype) {
 212                 case atype_integer:
 213                 case atype_enum:
 214                         field_offset += sizeof(int64_t);
 215                         break;
 216                 case atype_array:
 217                 case atype_sequence:
 218                         field_offset += sizeof(unsigned long);
 219                         field_offset += sizeof(void *);
 220                         break;
 221                 case atype_string:
 222                         field_offset += sizeof(void *);
 223                         break;
 224                 case atype_float:
 225                         field_offset += sizeof(double);
 226                         break;
 227                 default:
 228                         return -EINVAL;
 229                 }
 230         }
 231         if (!field)
 232                 return -EINVAL;
 233
 234         /* Check if field offset is too large for 16-bit offset */
 235         if (field_offset > FILTER_BYTECODE_MAX_LEN - 1)
 236                 return -EINVAL;
 237
 238         /* set type */
 239         op = (struct load_op *) &runtime->code[reloc_offset];
 240
 241         switch (filter_op) {
 242         case FILTER_OP_LOAD_FIELD_REF:
 243         {
 244                 struct field_ref *field_ref;
 245
 246                 field_ref = (struct field_ref *) op->data;
 247                 switch (field->type.atype) {
 248                 case atype_integer:
 249                 case atype_enum:
 250                         op->op = FILTER_OP_LOAD_FIELD_REF_S64;
 251                         break;
 252                 case atype_array:
 253                 case atype_sequence:
 254                         op->op = FILTER_OP_LOAD_FIELD_REF_SEQUENCE;
 255                         break;
 256                 case atype_string:
 257                         op->op = FILTER_OP_LOAD_FIELD_REF_STRING;
 258                         break;
 259                 case atype_float:
 260                         op->op = FILTER_OP_LOAD_FIELD_REF_DOUBLE;
 261                         break;
 262                 default:
 263                         return -EINVAL;
 264                 }
 265                 /* set offset */
 266                 field_ref->offset = (uint16_t) field_offset;
 267                 break;
 268         }
 269         default:
 270                 return -EINVAL;
 271         }
 272         return 0;
 273 }
 274
 275 static
 276 int apply_context_reloc(struct lttng_event *event,
 277                 struct bytecode_runtime *runtime,
 278                 uint32_t runtime_len,
 279                 uint32_t reloc_offset,
 280                 const char *context_name,
 281                 enum filter_op filter_op)
 282 {
 283         struct load_op *op;
 284         struct lttng_ctx_field *ctx_field;
 285         int idx;
 286         struct lttng_session *session = runtime->p.session;
 287
 288         dbg_printf("Apply context reloc: %u %s\n", reloc_offset, context_name);
 289
 290         /* Get context index */
 291         idx = lttng_get_context_index(session->ctx, context_name);
 292         if (idx < 0) {
 293                 if (lttng_context_is_app(context_name)) {
 294                         int ret;
 295
 296                         ret = lttng_ust_add_app_context_to_ctx_rcu(context_name,
 297                                         &session->ctx);
 298                         if (ret)
 299                                 return ret;
 300                         idx = lttng_get_context_index(session->ctx,
 301                                 context_name);
 302                         if (idx < 0)
 303                                 return -ENOENT;
 304                 } else {
 305                         return -ENOENT;
 306                 }
 307         }
 308         /* Check if idx is too large for 16-bit offset */
 309         if (idx > FILTER_BYTECODE_MAX_LEN - 1)
 310                 return -EINVAL;
 311
 312         /* Get context return type */
 313         ctx_field = &session->ctx->fields[idx];
 314         op = (struct load_op *) &runtime->code[reloc_offset];
 315
 316         switch (filter_op) {
 317         case FILTER_OP_GET_CONTEXT_REF:
 318         {
 319                 struct field_ref *field_ref;
 320
 321                 field_ref = (struct field_ref *) op->data;
 322                 switch (ctx_field->event_field.type.atype) {
 323                 case atype_integer:
 324                 case atype_enum:
 325                         op->op = FILTER_OP_GET_CONTEXT_REF_S64;
 326                         break;
 327                         /* Sequence and array supported as string */
 328                 case atype_string:
 329                 case atype_array:
 330                 case atype_sequence:
 331                         op->op = FILTER_OP_GET_CONTEXT_REF_STRING;
 332                         break;
 333                 case atype_float:
 334                         op->op = FILTER_OP_GET_CONTEXT_REF_DOUBLE;
 335                         break;
 336                 case atype_dynamic:
 337                         op->op = FILTER_OP_GET_CONTEXT_REF;
 338                         break;
 339                 default:
 340                         return -EINVAL;
 341                 }
 342                 /* set offset to context index within channel contexts */
 343                 field_ref->offset = (uint16_t) idx;
 344                 break;
 345         }
 346         default:
 347                 return -EINVAL;
 348         }
 349         return 0;
 350 }
 351
 352 static
 353 int apply_reloc(struct lttng_event *event,
 354                 struct bytecode_runtime *runtime,
 355                 uint32_t runtime_len,
 356                 uint32_t reloc_offset,
 357                 const char *name)
 358 {
 359         struct load_op *op;
 360
 361         dbg_printf("Apply reloc: %u %s\n", reloc_offset, name);
 362
 363         /* Ensure that the reloc is within the code */
 364         if (runtime_len - reloc_offset < sizeof(uint16_t))
 365                 return -EINVAL;
 366
 367         op = (struct load_op *) &runtime->code[reloc_offset];
 368         switch (op->op) {
 369         case FILTER_OP_LOAD_FIELD_REF:
 370                 return apply_field_reloc(event, runtime, runtime_len,
 371                         reloc_offset, name, op->op);
 372         case FILTER_OP_GET_CONTEXT_REF:
 373                 return apply_context_reloc(event, runtime, runtime_len,
 374                         reloc_offset, name, op->op);
 375         case FILTER_OP_GET_SYMBOL:
 376         case FILTER_OP_GET_SYMBOL_FIELD:
 377                 /*
 378                  * Will be handled by load specialize phase or
 379                  * dynamically by interpreter.
 380                  */
 381                 return 0;
 382         default:
 383                 ERR("Unknown reloc op type %u\n", op->op);
 384                 return -EINVAL;
 385         }
 386         return 0;
 387 }
 388
 389 static
 390 int bytecode_is_linked(struct lttng_ust_filter_bytecode_node *filter_bytecode,
 391                 struct lttng_event *event)
 392 {
 393         struct lttng_bytecode_runtime *bc_runtime;
 394
 395         cds_list_for_each_entry(bc_runtime,
 396                         &event->bytecode_runtime_head, node) {
 397                 if (bc_runtime->bc == filter_bytecode)
 398                         return 1;
 399         }
 400         return 0;
 401 }
 402
 403 /*
 404  * Take a bytecode with reloc table and link it to an event to create a
 405  * bytecode runtime.
 406  */
 407 static
 408 int _lttng_filter_event_link_bytecode(struct lttng_event *event,
 409                 struct lttng_ust_filter_bytecode_node *filter_bytecode,
 410                 struct cds_list_head *insert_loc)
 411 {
 412         int ret, offset, next_offset;
 413         struct bytecode_runtime *runtime = NULL;
 414         size_t runtime_alloc_len;
 415
 416         if (!filter_bytecode)
 417                 return 0;
 418         /* Bytecode already linked */
 419         if (bytecode_is_linked(filter_bytecode, event))
 420                 return 0;
 421
 422         dbg_printf("Linking...\n");
 423
 424         /* We don't need the reloc table in the runtime */
 425         runtime_alloc_len = sizeof(*runtime) + filter_bytecode->bc.reloc_offset;
 426         runtime = zmalloc(runtime_alloc_len);
 427         if (!runtime) {
 428                 ret = -ENOMEM;
 429                 goto alloc_error;
 430         }
 431         runtime->p.bc = filter_bytecode;
 432         runtime->p.session = event->chan->session;
 433         runtime->p.event = event;
 434         runtime->len = filter_bytecode->bc.reloc_offset;
 435         /* copy original bytecode */
 436         memcpy(runtime->code, filter_bytecode->bc.data, runtime->len);
 437         /*
 438          * apply relocs. Those are a uint16_t (offset in bytecode)
 439          * followed by a string (field name).
 440          */
 441         for (offset = filter_bytecode->bc.reloc_offset;
 442                         offset < filter_bytecode->bc.len;
 443                         offset = next_offset) {
 444                 uint16_t reloc_offset =
 445                         *(uint16_t *) &filter_bytecode->bc.data[offset];
 446                 const char *name =
 447                         (const char *) &filter_bytecode->bc.data[offset + sizeof(uint16_t)];
 448
 449                 ret = apply_reloc(event, runtime, runtime->len, reloc_offset, name);
 450                 if (ret) {
 451                         goto link_error;
 452                 }
 453                 next_offset = offset + sizeof(uint16_t) + strlen(name) + 1;
 454         }
 455         /* Validate bytecode */
 456         ret = lttng_filter_validate_bytecode(runtime);
 457         if (ret) {
 458                 goto link_error;
 459         }
 460         /* Specialize bytecode */
 461         ret = lttng_filter_specialize_bytecode(event, runtime);
 462         if (ret) {
 463                 goto link_error;
 464         }
 465         runtime->p.filter = lttng_filter_interpret_bytecode;
 466         runtime->p.link_failed = 0;
 467         cds_list_add_rcu(&runtime->p.node, insert_loc);
 468         dbg_printf("Linking successful.\n");
 469         return 0;
 470
 471 link_error:
 472         runtime->p.filter = lttng_filter_false;
 473         runtime->p.link_failed = 1;
 474         cds_list_add_rcu(&runtime->p.node, insert_loc);
 475 alloc_error:
 476         dbg_printf("Linking failed.\n");
 477         return ret;
 478 }
 479
 480 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime)
 481 {
 482         struct lttng_ust_filter_bytecode_node *bc = runtime->bc;
 483
 484         if (!bc->enabler->enabled || runtime->link_failed)
 485                 runtime->filter = lttng_filter_false;
 486         else
 487                 runtime->filter = lttng_filter_interpret_bytecode;
 488 }
 489
 490 /*
 491  * Link bytecode for all enablers referenced by an event.
 492  */
 493 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 494                 struct lttng_enabler *enabler)
 495 {
 496         struct lttng_ust_filter_bytecode_node *bc;
 497         struct lttng_bytecode_runtime *runtime;
 498
 499         /* Can only be called for events with desc attached */
 500         assert(event->desc);
 501
 502         /* Link each bytecode. */
 503         cds_list_for_each_entry(bc, &enabler->filter_bytecode_head, node) {
 504                 int found = 0, ret;
 505                 struct cds_list_head *insert_loc;
 506
 507                 cds_list_for_each_entry(runtime,
 508                                 &event->bytecode_runtime_head, node) {
 509                         if (runtime->bc == bc) {
 510                                 found = 1;
 511                                 break;
 512                         }
 513                 }
 514                 /* Skip bytecode already linked */
 515                 if (found)
 516                         continue;
 517
 518                 /*
 519                  * Insert at specified priority (seqnum) in increasing
 520                  * order.
 521                  */
 522                 cds_list_for_each_entry_reverse(runtime,
 523                                 &event->bytecode_runtime_head, node) {
 524                         if (runtime->bc->bc.seqnum < bc->bc.seqnum) {
 525                                 /* insert here */
 526                                 insert_loc = &runtime->node;
 527                                 goto add_within;
 528                         }
 529                 }
 530                 /* Add to head to list */
 531                 insert_loc = &event->bytecode_runtime_head;
 532         add_within:
 533                 dbg_printf("linking bytecode\n");
 534                 ret = _lttng_filter_event_link_bytecode(event, bc,
 535                                 insert_loc);
 536                 if (ret) {
 537                         dbg_printf("[lttng filter] warning: cannot link event bytecode\n");
 538                 }
 539         }
 540 }
 541
 542 /*
 543  * We own the filter_bytecode if we return success.
 544  */
 545 int lttng_filter_enabler_attach_bytecode(struct lttng_enabler *enabler,
 546                 struct lttng_ust_filter_bytecode_node *filter_bytecode)
 547 {
 548         cds_list_add(&filter_bytecode->node, &enabler->filter_bytecode_head);
 549         return 0;
 550 }
 551
 552 void lttng_free_enabler_filter_bytecode(struct lttng_enabler *enabler)
 553 {
 554         struct lttng_ust_filter_bytecode_node *filter_bytecode, *tmp;
 555
 556         cds_list_for_each_entry_safe(filter_bytecode, tmp,
 557                         &enabler->filter_bytecode_head, node) {
 558                 free(filter_bytecode);
 559         }
 560 }
 561
 562 void lttng_free_event_filter_runtime(struct lttng_event *event)
 563 {
 564         struct bytecode_runtime *runtime, *tmp;
 565
 566         cds_list_for_each_entry_safe(runtime, tmp,
 567                         &event->bytecode_runtime_head, p.node) {
 568                 free(runtime->data);
 569                 free(runtime);
 570         }
 571 }