lttng-filter.c

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