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 <stddef.h>
  29 #include <stdint.h>
  30
  31 #include <urcu/rculist.h>
  32
  33 #include "lttng-filter.h"
  34
  35 static const char *opnames[] = {
  36         [ FILTER_OP_UNKNOWN ] = "UNKNOWN",
  37
  38         [ FILTER_OP_RETURN ] = "RETURN",
  39
  40         /* binary */
  41         [ FILTER_OP_MUL ] = "MUL",
  42         [ FILTER_OP_DIV ] = "DIV",
  43         [ FILTER_OP_MOD ] = "MOD",
  44         [ FILTER_OP_PLUS ] = "PLUS",
  45         [ FILTER_OP_MINUS ] = "MINUS",
  46         [ FILTER_OP_BIT_RSHIFT ] = "BIT_RSHIFT",
  47         [ FILTER_OP_BIT_LSHIFT ] = "BIT_LSHIFT",
  48         [ FILTER_OP_BIT_AND ] = "BIT_AND",
  49         [ FILTER_OP_BIT_OR ] = "BIT_OR",
  50         [ FILTER_OP_BIT_XOR ] = "BIT_XOR",
  51
  52         /* binary comparators */
  53         [ FILTER_OP_EQ ] = "EQ",
  54         [ FILTER_OP_NE ] = "NE",
  55         [ FILTER_OP_GT ] = "GT",
  56         [ FILTER_OP_LT ] = "LT",
  57         [ FILTER_OP_GE ] = "GE",
  58         [ FILTER_OP_LE ] = "LE",
  59
  60         /* string binary comparators */
  61         [ FILTER_OP_EQ_STRING ] = "EQ_STRING",
  62         [ FILTER_OP_NE_STRING ] = "NE_STRING",
  63         [ FILTER_OP_GT_STRING ] = "GT_STRING",
  64         [ FILTER_OP_LT_STRING ] = "LT_STRING",
  65         [ FILTER_OP_GE_STRING ] = "GE_STRING",
  66         [ FILTER_OP_LE_STRING ] = "LE_STRING",
  67
  68         /* s64 binary comparators */
  69         [ FILTER_OP_EQ_S64 ] = "EQ_S64",
  70         [ FILTER_OP_NE_S64 ] = "NE_S64",
  71         [ FILTER_OP_GT_S64 ] = "GT_S64",
  72         [ FILTER_OP_LT_S64 ] = "LT_S64",
  73         [ FILTER_OP_GE_S64 ] = "GE_S64",
  74         [ FILTER_OP_LE_S64 ] = "LE_S64",
  75
  76         /* double binary comparators */
  77         [ FILTER_OP_EQ_DOUBLE ] = "EQ_DOUBLE",
  78         [ FILTER_OP_NE_DOUBLE ] = "NE_DOUBLE",
  79         [ FILTER_OP_GT_DOUBLE ] = "GT_DOUBLE",
  80         [ FILTER_OP_LT_DOUBLE ] = "LT_DOUBLE",
  81         [ FILTER_OP_GE_DOUBLE ] = "GE_DOUBLE",
  82         [ FILTER_OP_LE_DOUBLE ] = "LE_DOUBLE",
  83
  84         /* Mixed S64-double binary comparators */
  85         [ FILTER_OP_EQ_DOUBLE_S64 ] = "EQ_DOUBLE_S64",
  86         [ FILTER_OP_NE_DOUBLE_S64 ] = "NE_DOUBLE_S64",
  87         [ FILTER_OP_GT_DOUBLE_S64 ] = "GT_DOUBLE_S64",
  88         [ FILTER_OP_LT_DOUBLE_S64 ] = "LT_DOUBLE_S64",
  89         [ FILTER_OP_GE_DOUBLE_S64 ] = "GE_DOUBLE_S64",
  90         [ FILTER_OP_LE_DOUBLE_S64 ] = "LE_DOUBLE_S64",
  91
  92         [ FILTER_OP_EQ_S64_DOUBLE ] = "EQ_S64_DOUBLE",
  93         [ FILTER_OP_NE_S64_DOUBLE ] = "NE_S64_DOUBLE",
  94         [ FILTER_OP_GT_S64_DOUBLE ] = "GT_S64_DOUBLE",
  95         [ FILTER_OP_LT_S64_DOUBLE ] = "LT_S64_DOUBLE",
  96         [ FILTER_OP_GE_S64_DOUBLE ] = "GE_S64_DOUBLE",
  97         [ FILTER_OP_LE_S64_DOUBLE ] = "LE_S64_DOUBLE",
  98
  99         /* unary */
 100         [ FILTER_OP_UNARY_PLUS ] = "UNARY_PLUS",
 101         [ FILTER_OP_UNARY_MINUS ] = "UNARY_MINUS",
 102         [ FILTER_OP_UNARY_NOT ] = "UNARY_NOT",
 103         [ FILTER_OP_UNARY_PLUS_S64 ] = "UNARY_PLUS_S64",
 104         [ FILTER_OP_UNARY_MINUS_S64 ] = "UNARY_MINUS_S64",
 105         [ FILTER_OP_UNARY_NOT_S64 ] = "UNARY_NOT_S64",
 106         [ FILTER_OP_UNARY_PLUS_DOUBLE ] = "UNARY_PLUS_DOUBLE",
 107         [ FILTER_OP_UNARY_MINUS_DOUBLE ] = "UNARY_MINUS_DOUBLE",
 108         [ FILTER_OP_UNARY_NOT_DOUBLE ] = "UNARY_NOT_DOUBLE",
 109
 110         /* logical */
 111         [ FILTER_OP_AND ] = "AND",
 112         [ FILTER_OP_OR ] = "OR",
 113
 114         /* load field ref */
 115         [ FILTER_OP_LOAD_FIELD_REF ] = "LOAD_FIELD_REF",
 116         [ FILTER_OP_LOAD_FIELD_REF_STRING ] = "LOAD_FIELD_REF_STRING",
 117         [ FILTER_OP_LOAD_FIELD_REF_SEQUENCE ] = "LOAD_FIELD_REF_SEQUENCE",
 118         [ FILTER_OP_LOAD_FIELD_REF_S64 ] = "LOAD_FIELD_REF_S64",
 119         [ FILTER_OP_LOAD_FIELD_REF_DOUBLE ] = "LOAD_FIELD_REF_DOUBLE",
 120
 121         /* load from immediate operand */
 122         [ FILTER_OP_LOAD_STRING ] = "LOAD_STRING",
 123         [ FILTER_OP_LOAD_S64 ] = "LOAD_S64",
 124         [ FILTER_OP_LOAD_DOUBLE ] = "LOAD_DOUBLE",
 125
 126         /* cast */
 127         [ FILTER_OP_CAST_TO_S64 ] = "CAST_TO_S64",
 128         [ FILTER_OP_CAST_DOUBLE_TO_S64 ] = "CAST_DOUBLE_TO_S64",
 129         [ FILTER_OP_CAST_NOP ] = "CAST_NOP",
 130
 131         /* get context ref */
 132         [ FILTER_OP_GET_CONTEXT_REF ] = "GET_CONTEXT_REF",
 133         [ FILTER_OP_GET_CONTEXT_REF_STRING ] = "GET_CONTEXT_REF_STRING",
 134         [ FILTER_OP_GET_CONTEXT_REF_S64 ] = "GET_CONTEXT_REF_S64",
 135         [ FILTER_OP_GET_CONTEXT_REF_DOUBLE ] = "GET_CONTEXT_REF_DOUBLE",
 136
 137         /* load userspace field ref */
 138         [ FILTER_OP_LOAD_FIELD_REF_USER_STRING ] = "LOAD_FIELD_REF_USER_STRING",
 139         [ FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE ] = "LOAD_FIELD_REF_USER_SEQUENCE",
 140
 141         /*
 142          * load immediate star globbing pattern (literal string)
 143          * from immediate.
 144          */
 145         [ FILTER_OP_LOAD_STAR_GLOB_STRING ] = "LOAD_STAR_GLOB_STRING",
 146
 147         /* globbing pattern binary operator: apply to */
 148         [ FILTER_OP_EQ_STAR_GLOB_STRING ] = "EQ_STAR_GLOB_STRING",
 149         [ FILTER_OP_NE_STAR_GLOB_STRING ] = "NE_STAR_GLOB_STRING",
 150
 151         /*
 152          * Instructions for recursive traversal through composed types.
 153          */
 154         [ FILTER_OP_GET_CONTEXT_ROOT ] = "GET_CONTEXT_ROOT",
 155         [ FILTER_OP_GET_APP_CONTEXT_ROOT ] = "GET_APP_CONTEXT_ROOT",
 156         [ FILTER_OP_GET_PAYLOAD_ROOT ] = "GET_PAYLOAD_ROOT",
 157
 158         [ FILTER_OP_GET_SYMBOL ] = "GET_SYMBOL",
 159         [ FILTER_OP_GET_SYMBOL_FIELD ] = "GET_SYMBOL_FIELD",
 160         [ FILTER_OP_GET_INDEX_U16 ] = "GET_INDEX_U16",
 161         [ FILTER_OP_GET_INDEX_U64 ] = "GET_INDEX_U64",
 162
 163         [ FILTER_OP_LOAD_FIELD ] = "LOAD_FIELD",
 164         [ FILTER_OP_LOAD_FIELD_S8 ] = "LOAD_FIELD_S8",
 165         [ FILTER_OP_LOAD_FIELD_S16 ] = "LOAD_FIELD_S16",
 166         [ FILTER_OP_LOAD_FIELD_S32 ] = "LOAD_FIELD_S32",
 167         [ FILTER_OP_LOAD_FIELD_S64 ] = "LOAD_FIELD_S64",
 168         [ FILTER_OP_LOAD_FIELD_U8 ] = "LOAD_FIELD_U8",
 169         [ FILTER_OP_LOAD_FIELD_U16 ] = "LOAD_FIELD_U16",
 170         [ FILTER_OP_LOAD_FIELD_U32 ] = "LOAD_FIELD_U32",
 171         [ FILTER_OP_LOAD_FIELD_U64 ] = "LOAD_FIELD_U64",
 172         [ FILTER_OP_LOAD_FIELD_STRING ] = "LOAD_FIELD_STRING",
 173         [ FILTER_OP_LOAD_FIELD_SEQUENCE ] = "LOAD_FIELD_SEQUENCE",
 174         [ FILTER_OP_LOAD_FIELD_DOUBLE ] = "LOAD_FIELD_DOUBLE",
 175
 176         [ FILTER_OP_UNARY_BIT_NOT ] = "UNARY_BIT_NOT",
 177
 178         [ FILTER_OP_RETURN_S64 ] = "RETURN_S64",
 179 };
 180
 181 const char *print_op(enum filter_op op)
 182 {
 183         if (op >= NR_FILTER_OPS)
 184                 return "UNKNOWN";
 185         else
 186                 return opnames[op];
 187 }
 188
 189 static
 190 int apply_field_reloc(struct lttng_event *event,
 191                 struct bytecode_runtime *runtime,
 192                 uint32_t runtime_len,
 193                 uint32_t reloc_offset,
 194                 const char *field_name,
 195                 enum filter_op filter_op)
 196 {
 197         const struct lttng_event_desc *desc;
 198         const struct lttng_event_field *fields, *field = NULL;
 199         unsigned int nr_fields, i;
 200         struct load_op *op;
 201         uint32_t field_offset = 0;
 202
 203         dbg_printf("Apply field reloc: %u %s\n", reloc_offset, field_name);
 204
 205         /* Lookup event by name */
 206         desc = event->desc;
 207         if (!desc)
 208                 return -EINVAL;
 209         fields = desc->fields;
 210         if (!fields)
 211                 return -EINVAL;
 212         nr_fields = desc->nr_fields;
 213         for (i = 0; i < nr_fields; i++) {
 214                 if (!strcmp(fields[i].name, field_name)) {
 215                         field = &fields[i];
 216                         break;
 217                 }
 218                 /* compute field offset */
 219                 switch (fields[i].type.atype) {
 220                 case atype_integer:
 221                 case atype_enum:
 222                         field_offset += sizeof(int64_t);
 223                         break;
 224                 case atype_array:
 225                 case atype_sequence:
 226                         field_offset += sizeof(unsigned long);
 227                         field_offset += sizeof(void *);
 228                         break;
 229                 case atype_string:
 230                         field_offset += sizeof(void *);
 231                         break;
 232                 case atype_float:
 233                         field_offset += sizeof(double);
 234                         break;
 235                 default:
 236                         return -EINVAL;
 237                 }
 238         }
 239         if (!field)
 240                 return -EINVAL;
 241
 242         /* Check if field offset is too large for 16-bit offset */
 243         if (field_offset > FILTER_BYTECODE_MAX_LEN - 1)
 244                 return -EINVAL;
 245
 246         /* set type */
 247         op = (struct load_op *) &runtime->code[reloc_offset];
 248
 249         switch (filter_op) {
 250         case FILTER_OP_LOAD_FIELD_REF:
 251         {
 252                 struct field_ref *field_ref;
 253
 254                 field_ref = (struct field_ref *) op->data;
 255                 switch (field->type.atype) {
 256                 case atype_integer:
 257                 case atype_enum:
 258                         op->op = FILTER_OP_LOAD_FIELD_REF_S64;
 259                         break;
 260                 case atype_array:
 261                 case atype_sequence:
 262                         op->op = FILTER_OP_LOAD_FIELD_REF_SEQUENCE;
 263                         break;
 264                 case atype_string:
 265                         op->op = FILTER_OP_LOAD_FIELD_REF_STRING;
 266                         break;
 267                 case atype_float:
 268                         op->op = FILTER_OP_LOAD_FIELD_REF_DOUBLE;
 269                         break;
 270                 default:
 271                         return -EINVAL;
 272                 }
 273                 /* set offset */
 274                 field_ref->offset = (uint16_t) field_offset;
 275                 break;
 276         }
 277         default:
 278                 return -EINVAL;
 279         }
 280         return 0;
 281 }
 282
 283 static
 284 int apply_context_reloc(struct lttng_event *event,
 285                 struct bytecode_runtime *runtime,
 286                 uint32_t runtime_len,
 287                 uint32_t reloc_offset,
 288                 const char *context_name,
 289                 enum filter_op filter_op)
 290 {
 291         struct load_op *op;
 292         struct lttng_ctx_field *ctx_field;
 293         int idx;
 294         struct lttng_session *session = runtime->p.session;
 295
 296         dbg_printf("Apply context reloc: %u %s\n", reloc_offset, context_name);
 297
 298         /* Get context index */
 299         idx = lttng_get_context_index(session->ctx, context_name);
 300         if (idx < 0) {
 301                 if (lttng_context_is_app(context_name)) {
 302                         int ret;
 303
 304                         ret = lttng_ust_add_app_context_to_ctx_rcu(context_name,
 305                                         &session->ctx);
 306                         if (ret)
 307                                 return ret;
 308                         idx = lttng_get_context_index(session->ctx,
 309                                 context_name);
 310                         if (idx < 0)
 311                                 return -ENOENT;
 312                 } else {
 313                         return -ENOENT;
 314                 }
 315         }
 316         /* Check if idx is too large for 16-bit offset */
 317         if (idx > FILTER_BYTECODE_MAX_LEN - 1)
 318                 return -EINVAL;
 319
 320         /* Get context return type */
 321         ctx_field = &session->ctx->fields[idx];
 322         op = (struct load_op *) &runtime->code[reloc_offset];
 323
 324         switch (filter_op) {
 325         case FILTER_OP_GET_CONTEXT_REF:
 326         {
 327                 struct field_ref *field_ref;
 328
 329                 field_ref = (struct field_ref *) op->data;
 330                 switch (ctx_field->event_field.type.atype) {
 331                 case atype_integer:
 332                 case atype_enum:
 333                         op->op = FILTER_OP_GET_CONTEXT_REF_S64;
 334                         break;
 335                         /* Sequence and array supported as string */
 336                 case atype_string:
 337                 case atype_array:
 338                 case atype_sequence:
 339                         op->op = FILTER_OP_GET_CONTEXT_REF_STRING;
 340                         break;
 341                 case atype_float:
 342                         op->op = FILTER_OP_GET_CONTEXT_REF_DOUBLE;
 343                         break;
 344                 case atype_dynamic:
 345                         op->op = FILTER_OP_GET_CONTEXT_REF;
 346                         break;
 347                 default:
 348                         return -EINVAL;
 349                 }
 350                 /* set offset to context index within channel contexts */
 351                 field_ref->offset = (uint16_t) idx;
 352                 break;
 353         }
 354         default:
 355                 return -EINVAL;
 356         }
 357         return 0;
 358 }
 359
 360 static
 361 int apply_reloc(struct lttng_event *event,
 362                 struct bytecode_runtime *runtime,
 363                 uint32_t runtime_len,
 364                 uint32_t reloc_offset,
 365                 const char *name)
 366 {
 367         struct load_op *op;
 368
 369         dbg_printf("Apply reloc: %u %s\n", reloc_offset, name);
 370
 371         /* Ensure that the reloc is within the code */
 372         if (runtime_len - reloc_offset < sizeof(uint16_t))
 373                 return -EINVAL;
 374
 375         op = (struct load_op *) &runtime->code[reloc_offset];
 376         switch (op->op) {
 377         case FILTER_OP_LOAD_FIELD_REF:
 378                 return apply_field_reloc(event, runtime, runtime_len,
 379                         reloc_offset, name, op->op);
 380         case FILTER_OP_GET_CONTEXT_REF:
 381                 return apply_context_reloc(event, runtime, runtime_len,
 382                         reloc_offset, name, op->op);
 383         case FILTER_OP_GET_SYMBOL:
 384         case FILTER_OP_GET_SYMBOL_FIELD:
 385                 /*
 386                  * Will be handled by load specialize phase or
 387                  * dynamically by interpreter.
 388                  */
 389                 return 0;
 390         default:
 391                 ERR("Unknown reloc op type %u\n", op->op);
 392                 return -EINVAL;
 393         }
 394         return 0;
 395 }
 396
 397 static
 398 int bytecode_is_linked(struct lttng_ust_filter_bytecode_node *filter_bytecode,
 399                 struct lttng_event *event)
 400 {
 401         struct lttng_bytecode_runtime *bc_runtime;
 402
 403         cds_list_for_each_entry(bc_runtime,
 404                         &event->bytecode_runtime_head, node) {
 405                 if (bc_runtime->bc == filter_bytecode)
 406                         return 1;
 407         }
 408         return 0;
 409 }
 410
 411 /*
 412  * Take a bytecode with reloc table and link it to an event to create a
 413  * bytecode runtime.
 414  */
 415 static
 416 int _lttng_filter_event_link_bytecode(struct lttng_event *event,
 417                 struct lttng_ust_filter_bytecode_node *filter_bytecode,
 418                 struct cds_list_head *insert_loc)
 419 {
 420         int ret, offset, next_offset;
 421         struct bytecode_runtime *runtime = NULL;
 422         size_t runtime_alloc_len;
 423
 424         if (!filter_bytecode)
 425                 return 0;
 426         /* Bytecode already linked */
 427         if (bytecode_is_linked(filter_bytecode, event))
 428                 return 0;
 429
 430         dbg_printf("Linking...\n");
 431
 432         /* We don't need the reloc table in the runtime */
 433         runtime_alloc_len = sizeof(*runtime) + filter_bytecode->bc.reloc_offset;
 434         runtime = zmalloc(runtime_alloc_len);
 435         if (!runtime) {
 436                 ret = -ENOMEM;
 437                 goto alloc_error;
 438         }
 439         runtime->p.bc = filter_bytecode;
 440         runtime->p.session = event->chan->session;
 441         runtime->p.event = event;
 442         runtime->len = filter_bytecode->bc.reloc_offset;
 443         /* copy original bytecode */
 444         memcpy(runtime->code, filter_bytecode->bc.data, runtime->len);
 445         /*
 446          * apply relocs. Those are a uint16_t (offset in bytecode)
 447          * followed by a string (field name).
 448          */
 449         for (offset = filter_bytecode->bc.reloc_offset;
 450                         offset < filter_bytecode->bc.len;
 451                         offset = next_offset) {
 452                 uint16_t reloc_offset =
 453                         *(uint16_t *) &filter_bytecode->bc.data[offset];
 454                 const char *name =
 455                         (const char *) &filter_bytecode->bc.data[offset + sizeof(uint16_t)];
 456
 457                 ret = apply_reloc(event, runtime, runtime->len, reloc_offset, name);
 458                 if (ret) {
 459                         goto link_error;
 460                 }
 461                 next_offset = offset + sizeof(uint16_t) + strlen(name) + 1;
 462         }
 463         /* Validate bytecode */
 464         ret = lttng_filter_validate_bytecode(runtime);
 465         if (ret) {
 466                 goto link_error;
 467         }
 468         /* Specialize bytecode */
 469         ret = lttng_filter_specialize_bytecode(event, runtime);
 470         if (ret) {
 471                 goto link_error;
 472         }
 473         runtime->p.filter = lttng_filter_interpret_bytecode;
 474         runtime->p.link_failed = 0;
 475         cds_list_add_rcu(&runtime->p.node, insert_loc);
 476         dbg_printf("Linking successful.\n");
 477         return 0;
 478
 479 link_error:
 480         runtime->p.filter = lttng_filter_false;
 481         runtime->p.link_failed = 1;
 482         cds_list_add_rcu(&runtime->p.node, insert_loc);
 483 alloc_error:
 484         dbg_printf("Linking failed.\n");
 485         return ret;
 486 }
 487
 488 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime)
 489 {
 490         struct lttng_ust_filter_bytecode_node *bc = runtime->bc;
 491
 492         if (!bc->enabler->enabled || runtime->link_failed)
 493                 runtime->filter = lttng_filter_false;
 494         else
 495                 runtime->filter = lttng_filter_interpret_bytecode;
 496 }
 497
 498 /*
 499  * Link bytecode for all enablers referenced by an event.
 500  */
 501 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 502                 struct lttng_enabler *enabler)
 503 {
 504         struct lttng_ust_filter_bytecode_node *bc;
 505         struct lttng_bytecode_runtime *runtime;
 506
 507         /* Can only be called for events with desc attached */
 508         assert(event->desc);
 509
 510         /* Link each bytecode. */
 511         cds_list_for_each_entry(bc, &enabler->filter_bytecode_head, node) {
 512                 int found = 0, ret;
 513                 struct cds_list_head *insert_loc;
 514
 515                 cds_list_for_each_entry(runtime,
 516                                 &event->bytecode_runtime_head, node) {
 517                         if (runtime->bc == bc) {
 518                                 found = 1;
 519                                 break;
 520                         }
 521                 }
 522                 /* Skip bytecode already linked */
 523                 if (found)
 524                         continue;
 525
 526                 /*
 527                  * Insert at specified priority (seqnum) in increasing
 528                  * order.
 529                  */
 530                 cds_list_for_each_entry_reverse(runtime,
 531                                 &event->bytecode_runtime_head, node) {
 532                         if (runtime->bc->bc.seqnum < bc->bc.seqnum) {
 533                                 /* insert here */
 534                                 insert_loc = &runtime->node;
 535                                 goto add_within;
 536                         }
 537                 }
 538                 /* Add to head to list */
 539                 insert_loc = &event->bytecode_runtime_head;
 540         add_within:
 541                 dbg_printf("linking bytecode\n");
 542                 ret = _lttng_filter_event_link_bytecode(event, bc,
 543                                 insert_loc);
 544                 if (ret) {
 545                         dbg_printf("[lttng filter] warning: cannot link event bytecode\n");
 546                 }
 547         }
 548 }
 549
 550 /*
 551  * We own the filter_bytecode if we return success.
 552  */
 553 int lttng_filter_enabler_attach_bytecode(struct lttng_enabler *enabler,
 554                 struct lttng_ust_filter_bytecode_node *filter_bytecode)
 555 {
 556         cds_list_add(&filter_bytecode->node, &enabler->filter_bytecode_head);
 557         return 0;
 558 }
 559
 560 void lttng_free_enabler_filter_bytecode(struct lttng_enabler *enabler)
 561 {
 562         struct lttng_ust_filter_bytecode_node *filter_bytecode, *tmp;
 563
 564         cds_list_for_each_entry_safe(filter_bytecode, tmp,
 565                         &enabler->filter_bytecode_head, node) {
 566                 free(filter_bytecode);
 567         }
 568 }
 569
 570 void lttng_free_event_filter_runtime(struct lttng_event *event)
 571 {
 572         struct bytecode_runtime *runtime, *tmp;
 573
 574         cds_list_for_each_entry_safe(runtime, tmp,
 575                         &event->bytecode_runtime_head, p.node) {
 576                 free(runtime->data);
 577                 free(runtime);
 578         }
 579 }