[lttng-ust.git] / liblttng-ust / lttng-filter.c

/*
 * lttng-filter.c
 *
 * LTTng UST filter code.
 *
 * Copyright (C) 2010-2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#define _LGPL_SOURCE
#include <stddef.h>
#include <urcu/rculist.h>
#include "lttng-filter.h"

static const char *opnames[] = {
	[ FILTER_OP_UNKNOWN ] = "UNKNOWN",

	[ FILTER_OP_RETURN ] = "RETURN",

	/* binary */
	[ FILTER_OP_MUL ] = "MUL",
	[ FILTER_OP_DIV ] = "DIV",
	[ FILTER_OP_MOD ] = "MOD",
	[ FILTER_OP_PLUS ] = "PLUS",
	[ FILTER_OP_MINUS ] = "MINUS",
	[ FILTER_OP_BIT_RSHIFT ] = "BIT_RSHIFT",
	[ FILTER_OP_BIT_LSHIFT ] = "BIT_LSHIFT",
	[ FILTER_OP_BIT_AND ] = "BIT_AND",
	[ FILTER_OP_BIT_OR ] = "BIT_OR",
	[ FILTER_OP_BIT_XOR ] = "BIT_XOR",

	/* binary comparators */
	[ FILTER_OP_EQ ] = "EQ",
	[ FILTER_OP_NE ] = "NE",
	[ FILTER_OP_GT ] = "GT",
	[ FILTER_OP_LT ] = "LT",
	[ FILTER_OP_GE ] = "GE",
	[ FILTER_OP_LE ] = "LE",

	/* string binary comparators */
	[ FILTER_OP_EQ_STRING ] = "EQ_STRING",
	[ FILTER_OP_NE_STRING ] = "NE_STRING",
	[ FILTER_OP_GT_STRING ] = "GT_STRING",
	[ FILTER_OP_LT_STRING ] = "LT_STRING",
	[ FILTER_OP_GE_STRING ] = "GE_STRING",
	[ FILTER_OP_LE_STRING ] = "LE_STRING",

	/* s64 binary comparators */
	[ FILTER_OP_EQ_S64 ] = "EQ_S64",
	[ FILTER_OP_NE_S64 ] = "NE_S64",
	[ FILTER_OP_GT_S64 ] = "GT_S64",
	[ FILTER_OP_LT_S64 ] = "LT_S64",
	[ FILTER_OP_GE_S64 ] = "GE_S64",
	[ FILTER_OP_LE_S64 ] = "LE_S64",

	/* double binary comparators */
	[ FILTER_OP_EQ_DOUBLE ] = "EQ_DOUBLE",
	[ FILTER_OP_NE_DOUBLE ] = "NE_DOUBLE",
	[ FILTER_OP_GT_DOUBLE ] = "GT_DOUBLE",
	[ FILTER_OP_LT_DOUBLE ] = "LT_DOUBLE",
	[ FILTER_OP_GE_DOUBLE ] = "GE_DOUBLE",
	[ FILTER_OP_LE_DOUBLE ] = "LE_DOUBLE",

	/* Mixed S64-double binary comparators */
	[ FILTER_OP_EQ_DOUBLE_S64 ] = "EQ_DOUBLE_S64",
	[ FILTER_OP_NE_DOUBLE_S64 ] = "NE_DOUBLE_S64",
	[ FILTER_OP_GT_DOUBLE_S64 ] = "GT_DOUBLE_S64",
	[ FILTER_OP_LT_DOUBLE_S64 ] = "LT_DOUBLE_S64",
	[ FILTER_OP_GE_DOUBLE_S64 ] = "GE_DOUBLE_S64",
	[ FILTER_OP_LE_DOUBLE_S64 ] = "LE_DOUBLE_S64",

	[ FILTER_OP_EQ_S64_DOUBLE ] = "EQ_S64_DOUBLE",
	[ FILTER_OP_NE_S64_DOUBLE ] = "NE_S64_DOUBLE",
	[ FILTER_OP_GT_S64_DOUBLE ] = "GT_S64_DOUBLE",
	[ FILTER_OP_LT_S64_DOUBLE ] = "LT_S64_DOUBLE",
	[ FILTER_OP_GE_S64_DOUBLE ] = "GE_S64_DOUBLE",
	[ FILTER_OP_LE_S64_DOUBLE ] = "LE_S64_DOUBLE",

	/* unary */
	[ FILTER_OP_UNARY_PLUS ] = "UNARY_PLUS",
	[ FILTER_OP_UNARY_MINUS ] = "UNARY_MINUS",
	[ FILTER_OP_UNARY_NOT ] = "UNARY_NOT",
	[ FILTER_OP_UNARY_PLUS_S64 ] = "UNARY_PLUS_S64",
	[ FILTER_OP_UNARY_MINUS_S64 ] = "UNARY_MINUS_S64",
	[ FILTER_OP_UNARY_NOT_S64 ] = "UNARY_NOT_S64",
	[ FILTER_OP_UNARY_PLUS_DOUBLE ] = "UNARY_PLUS_DOUBLE",
	[ FILTER_OP_UNARY_MINUS_DOUBLE ] = "UNARY_MINUS_DOUBLE",
	[ FILTER_OP_UNARY_NOT_DOUBLE ] = "UNARY_NOT_DOUBLE",

	/* logical */
	[ FILTER_OP_AND ] = "AND",
	[ FILTER_OP_OR ] = "OR",

	/* load field ref */
	[ FILTER_OP_LOAD_FIELD_REF ] = "LOAD_FIELD_REF",
	[ FILTER_OP_LOAD_FIELD_REF_STRING ] = "LOAD_FIELD_REF_STRING",
	[ FILTER_OP_LOAD_FIELD_REF_SEQUENCE ] = "LOAD_FIELD_REF_SEQUENCE",
	[ FILTER_OP_LOAD_FIELD_REF_S64 ] = "LOAD_FIELD_REF_S64",
	[ FILTER_OP_LOAD_FIELD_REF_DOUBLE ] = "LOAD_FIELD_REF_DOUBLE",

	/* load from immediate operand */
	[ FILTER_OP_LOAD_STRING ] = "LOAD_STRING",
	[ FILTER_OP_LOAD_S64 ] = "LOAD_S64",
	[ FILTER_OP_LOAD_DOUBLE ] = "LOAD_DOUBLE",

	/* cast */
	[ FILTER_OP_CAST_TO_S64 ] = "CAST_TO_S64",
	[ FILTER_OP_CAST_DOUBLE_TO_S64 ] = "CAST_DOUBLE_TO_S64",
	[ FILTER_OP_CAST_NOP ] = "CAST_NOP",

	/* get context ref */
	[ FILTER_OP_GET_CONTEXT_REF ] = "GET_CONTEXT_REF",
	[ FILTER_OP_GET_CONTEXT_REF_STRING ] = "GET_CONTEXT_REF_STRING",
	[ FILTER_OP_GET_CONTEXT_REF_S64 ] = "GET_CONTEXT_REF_S64",
	[ FILTER_OP_GET_CONTEXT_REF_DOUBLE ] = "GET_CONTEXT_REF_DOUBLE",

	/* load userspace field ref */
	[ FILTER_OP_LOAD_FIELD_REF_USER_STRING ] = "LOAD_FIELD_REF_USER_STRING",
	[ FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE ] = "LOAD_FIELD_REF_USER_SEQUENCE",

	/*
	 * load immediate star globbing pattern (literal string)
	 * from immediate.
	 */
	[ FILTER_OP_LOAD_STAR_GLOB_STRING ] = "LOAD_STAR_GLOB_STRING",

	/* globbing pattern binary operator: apply to */
	[ FILTER_OP_EQ_STAR_GLOB_STRING ] = "EQ_STAR_GLOB_STRING",
	[ FILTER_OP_NE_STAR_GLOB_STRING ] = "NE_STAR_GLOB_STRING",

	/*
	 * Instructions for recursive traversal through composed types.
	 */
	[ FILTER_OP_GET_CONTEXT_ROOT ] = "GET_CONTEXT_ROOT",
	[ FILTER_OP_GET_APP_CONTEXT_ROOT ] = "GET_APP_CONTEXT_ROOT",
	[ FILTER_OP_GET_PAYLOAD_ROOT ] = "GET_PAYLOAD_ROOT",

	[ FILTER_OP_GET_SYMBOL ] = "GET_SYMBOL",
	[ FILTER_OP_GET_SYMBOL_FIELD ] = "GET_SYMBOL_FIELD",
	[ FILTER_OP_GET_INDEX_U16 ] = "GET_INDEX_U16",
	[ FILTER_OP_GET_INDEX_U64 ] = "GET_INDEX_U64",

	[ FILTER_OP_LOAD_FIELD ] = "LOAD_FIELD",
	[ FILTER_OP_LOAD_FIELD_S8 ] = "LOAD_FIELD_S8",
	[ FILTER_OP_LOAD_FIELD_S16 ] = "LOAD_FIELD_S16",
	[ FILTER_OP_LOAD_FIELD_S32 ] = "LOAD_FIELD_S32",
	[ FILTER_OP_LOAD_FIELD_S64 ] = "LOAD_FIELD_S64",
	[ FILTER_OP_LOAD_FIELD_U8 ] = "LOAD_FIELD_U8",
	[ FILTER_OP_LOAD_FIELD_U16 ] = "LOAD_FIELD_U16",
	[ FILTER_OP_LOAD_FIELD_U32 ] = "LOAD_FIELD_U32",
	[ FILTER_OP_LOAD_FIELD_U64 ] = "LOAD_FIELD_U64",
	[ FILTER_OP_LOAD_FIELD_STRING ] = "LOAD_FIELD_STRING",
	[ FILTER_OP_LOAD_FIELD_SEQUENCE ] = "LOAD_FIELD_SEQUENCE",
	[ FILTER_OP_LOAD_FIELD_DOUBLE ] = "LOAD_FIELD_DOUBLE",

	[ FILTER_OP_UNARY_BIT_NOT ] = "UNARY_BIT_NOT",

	[ FILTER_OP_RETURN_S64 ] = "RETURN_S64",
};

const char *print_op(enum filter_op op)
{
	if (op >= NR_FILTER_OPS)
		return "UNKNOWN";
	else
		return opnames[op];
}

static
int apply_field_reloc(struct lttng_event *event,
		struct bytecode_runtime *runtime,
		uint32_t runtime_len,
		uint32_t reloc_offset,
		const char *field_name,
		enum filter_op filter_op)
{
	const struct lttng_event_desc *desc;
	const struct lttng_event_field *fields, *field = NULL;
	unsigned int nr_fields, i;
	struct load_op *op;
	uint32_t field_offset = 0;

	dbg_printf("Apply field reloc: %u %s\n", reloc_offset, field_name);

	/* Lookup event by name */
	desc = event->desc;
	if (!desc)
		return -EINVAL;
	fields = desc->fields;
	if (!fields)
		return -EINVAL;
	nr_fields = desc->nr_fields;
	for (i = 0; i < nr_fields; i++) {
		if (!strcmp(fields[i].name, field_name)) {
			field = &fields[i];
			break;
		}
		/* compute field offset */
		switch (fields[i].type.atype) {
		case atype_integer:
		case atype_enum:
			field_offset += sizeof(int64_t);
			break;
		case atype_array:
		case atype_sequence:
			field_offset += sizeof(unsigned long);
			field_offset += sizeof(void *);
			break;
		case atype_string:
			field_offset += sizeof(void *);
			break;
		case atype_float:
			field_offset += sizeof(double);
			break;
		default:
			return -EINVAL;
		}
	}
	if (!field)
		return -EINVAL;

	/* Check if field offset is too large for 16-bit offset */
	if (field_offset > FILTER_BYTECODE_MAX_LEN - 1)
		return -EINVAL;

	/* set type */
	op = (struct load_op *) &runtime->code[reloc_offset];

	switch (filter_op) {
	case FILTER_OP_LOAD_FIELD_REF:
	{
		struct field_ref *field_ref;

		field_ref = (struct field_ref *) op->data;
		switch (field->type.atype) {
		case atype_integer:
		case atype_enum:
			op->op = FILTER_OP_LOAD_FIELD_REF_S64;
			break;
		case atype_array:
		case atype_sequence:
			op->op = FILTER_OP_LOAD_FIELD_REF_SEQUENCE;
			break;
		case atype_string:
			op->op = FILTER_OP_LOAD_FIELD_REF_STRING;
			break;
		case atype_float:
			op->op = FILTER_OP_LOAD_FIELD_REF_DOUBLE;
			break;
		default:
			return -EINVAL;
		}
		/* set offset */
		field_ref->offset = (uint16_t) field_offset;
		break;
	}
	default:
		return -EINVAL;
	}
	return 0;
}

static
int apply_context_reloc(struct lttng_event *event,
		struct bytecode_runtime *runtime,
		uint32_t runtime_len,
		uint32_t reloc_offset,
		const char *context_name,
		enum filter_op filter_op)
{
	struct load_op *op;
	struct lttng_ctx_field *ctx_field;
	int idx;
	struct lttng_session *session = runtime->p.session;

	dbg_printf("Apply context reloc: %u %s\n", reloc_offset, context_name);

	/* Get context index */
	idx = lttng_get_context_index(session->ctx, context_name);
	if (idx < 0) {
		if (lttng_context_is_app(context_name)) {
			int ret;

			ret = lttng_ust_add_app_context_to_ctx_rcu(context_name,
					&session->ctx);
			if (ret)
				return ret;
			idx = lttng_get_context_index(session->ctx,
				context_name);
			if (idx < 0)
				return -ENOENT;
		} else {
			return -ENOENT;
		}
	}
	/* Check if idx is too large for 16-bit offset */
	if (idx > FILTER_BYTECODE_MAX_LEN - 1)
		return -EINVAL;

	/* Get context return type */
	ctx_field = &session->ctx->fields[idx];
	op = (struct load_op *) &runtime->code[reloc_offset];

	switch (filter_op) {
	case FILTER_OP_GET_CONTEXT_REF:
	{
		struct field_ref *field_ref;

		field_ref = (struct field_ref *) op->data;
		switch (ctx_field->event_field.type.atype) {
		case atype_integer:
		case atype_enum:
			op->op = FILTER_OP_GET_CONTEXT_REF_S64;
			break;
			/* Sequence and array supported as string */
		case atype_string:
		case atype_array:
		case atype_sequence:
			op->op = FILTER_OP_GET_CONTEXT_REF_STRING;
			break;
		case atype_float:
			op->op = FILTER_OP_GET_CONTEXT_REF_DOUBLE;
			break;
		case atype_dynamic:
			op->op = FILTER_OP_GET_CONTEXT_REF;
			break;
		default:
			return -EINVAL;
		}
		/* set offset to context index within channel contexts */
		field_ref->offset = (uint16_t) idx;
		break;
	}
	default:
		return -EINVAL;
	}
	return 0;
}

static
int apply_reloc(struct lttng_event *event,
		struct bytecode_runtime *runtime,
		uint32_t runtime_len,
		uint32_t reloc_offset,
		const char *name)
{
	struct load_op *op;

	dbg_printf("Apply reloc: %u %s\n", reloc_offset, name);

	/* Ensure that the reloc is within the code */
	if (runtime_len - reloc_offset < sizeof(uint16_t))
		return -EINVAL;

	op = (struct load_op *) &runtime->code[reloc_offset];
	switch (op->op) {
	case FILTER_OP_LOAD_FIELD_REF:
		return apply_field_reloc(event, runtime, runtime_len,
			reloc_offset, name, op->op);
	case FILTER_OP_GET_CONTEXT_REF:
		return apply_context_reloc(event, runtime, runtime_len,
			reloc_offset, name, op->op);
	case FILTER_OP_GET_SYMBOL:
	case FILTER_OP_GET_SYMBOL_FIELD:
		/*
		 * Will be handled by load specialize phase or
		 * dynamically by interpreter.
		 */
		return 0;
	default:
		ERR("Unknown reloc op type %u\n", op->op);
		return -EINVAL;
	}
	return 0;
}

static
int bytecode_is_linked(struct lttng_ust_filter_bytecode_node *filter_bytecode,
		struct lttng_event *event)
{
	struct lttng_bytecode_runtime *bc_runtime;

	cds_list_for_each_entry(bc_runtime,
			&event->bytecode_runtime_head, node) {
		if (bc_runtime->bc == filter_bytecode)
			return 1;
	}
	return 0;
}

/*
 * Take a bytecode with reloc table and link it to an event to create a
 * bytecode runtime.
 */
static
int _lttng_filter_event_link_bytecode(struct lttng_event *event,
		struct lttng_ust_filter_bytecode_node *filter_bytecode,
		struct cds_list_head *insert_loc)
{
	int ret, offset, next_offset;
	struct bytecode_runtime *runtime = NULL;
	size_t runtime_alloc_len;

	if (!filter_bytecode)
		return 0;
	/* Bytecode already linked */
	if (bytecode_is_linked(filter_bytecode, event))
		return 0;

	dbg_printf("Linking...\n");

	/* We don't need the reloc table in the runtime */
	runtime_alloc_len = sizeof(*runtime) + filter_bytecode->bc.reloc_offset;
	runtime = zmalloc(runtime_alloc_len);
	if (!runtime) {
		ret = -ENOMEM;
		goto alloc_error;
	}
	runtime->p.bc = filter_bytecode;
	runtime->p.session = event->chan->session;
	runtime->p.event = event;
	runtime->len = filter_bytecode->bc.reloc_offset;
	/* copy original bytecode */
	memcpy(runtime->code, filter_bytecode->bc.data, runtime->len);
	/*
	 * apply relocs. Those are a uint16_t (offset in bytecode)
	 * followed by a string (field name).
	 */
	for (offset = filter_bytecode->bc.reloc_offset;
			offset < filter_bytecode->bc.len;
			offset = next_offset) {
		uint16_t reloc_offset =
			*(uint16_t *) &filter_bytecode->bc.data[offset];
		const char *name =
			(const char *) &filter_bytecode->bc.data[offset + sizeof(uint16_t)];

		ret = apply_reloc(event, runtime, runtime->len, reloc_offset, name);
		if (ret) {
			goto link_error;
		}
		next_offset = offset + sizeof(uint16_t) + strlen(name) + 1;
	}
	/* Validate bytecode */
	ret = lttng_filter_validate_bytecode(runtime);
	if (ret) {
		goto link_error;
	}
	/* Specialize bytecode */
	ret = lttng_filter_specialize_bytecode(event, runtime);
	if (ret) {
		goto link_error;
	}
	runtime->p.filter = lttng_filter_interpret_bytecode;
	runtime->p.link_failed = 0;
	cds_list_add_rcu(&runtime->p.node, insert_loc);
	dbg_printf("Linking successful.\n");
	return 0;

link_error:
	runtime->p.filter = lttng_filter_false;
	runtime->p.link_failed = 1;
	cds_list_add_rcu(&runtime->p.node, insert_loc);
alloc_error:
	dbg_printf("Linking failed.\n");
	return ret;
}

void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime)
{
	struct lttng_ust_filter_bytecode_node *bc = runtime->bc;

	if (!bc->enabler->enabled || runtime->link_failed)
		runtime->filter = lttng_filter_false;
	else
		runtime->filter = lttng_filter_interpret_bytecode;
}

/*
 * Link bytecode for all enablers referenced by an event.
 */
void lttng_enabler_event_link_bytecode(struct lttng_event *event,
		struct lttng_enabler *enabler)
{
	struct lttng_ust_filter_bytecode_node *bc;
	struct lttng_bytecode_runtime *runtime;

	/* Can only be called for events with desc attached */
	assert(event->desc);

	/* Link each bytecode. */
	cds_list_for_each_entry(bc, &enabler->filter_bytecode_head, node) {
		int found = 0, ret;
		struct cds_list_head *insert_loc;

		cds_list_for_each_entry(runtime,
				&event->bytecode_runtime_head, node) {
			if (runtime->bc == bc) {
				found = 1;
				break;
			}
		}
		/* Skip bytecode already linked */
		if (found)
			continue;

		/*
		 * Insert at specified priority (seqnum) in increasing
		 * order.
		 */
		cds_list_for_each_entry_reverse(runtime,
				&event->bytecode_runtime_head, node) {
			if (runtime->bc->bc.seqnum < bc->bc.seqnum) {
				/* insert here */
				insert_loc = &runtime->node;
				goto add_within;
			}
		}
		/* Add to head to list */
		insert_loc = &event->bytecode_runtime_head;
	add_within:
		dbg_printf("linking bytecode\n");
		ret = _lttng_filter_event_link_bytecode(event, bc,
				insert_loc);
		if (ret) {
			dbg_printf("[lttng filter] warning: cannot link event bytecode\n");
		}
	}
}

/*
 * We own the filter_bytecode if we return success.
 */
int lttng_filter_enabler_attach_bytecode(struct lttng_enabler *enabler,
		struct lttng_ust_filter_bytecode_node *filter_bytecode)
{
	cds_list_add(&filter_bytecode->node, &enabler->filter_bytecode_head);
	return 0;
}

void lttng_free_enabler_filter_bytecode(struct lttng_enabler *enabler)
{
	struct lttng_ust_filter_bytecode_node *filter_bytecode, *tmp;

	cds_list_for_each_entry_safe(filter_bytecode, tmp,
			&enabler->filter_bytecode_head, node) {
		free(filter_bytecode);
	}
}

void lttng_free_event_filter_runtime(struct lttng_event *event)
{
	struct bytecode_runtime *runtime, *tmp;

	cds_list_for_each_entry_safe(runtime, tmp,
			&event->bytecode_runtime_head, p.node) {
		free(runtime->data);
		free(runtime);
	}
}
Commit	Line	Data
2d78951a MD	1	/*
	2	* lttng-filter.c
	3	*
	4	* LTTng UST filter code.
	5	*
7e50015d	6	* Copyright (C) 2010-2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
2d78951a	7	*
7e50015d MD	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:
2d78951a	14	*
7e50015d MD	15	* The above copyright notice and this permission notice shall be included in
7e50015d MD	16	* all copies or substantial portions of the Software.
2d78951a	17	*
7e50015d MD	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.
2d78951a MD	25	*/
2d78951a MD	26
3fbec7dc	27	#define _LGPL_SOURCE
b4051ad8	28	#include <stddef.h>
f488575f	29	#include <urcu/rculist.h>
97b58163	30	#include "lttng-filter.h"
cd54f6d9 MD	31
	32	static const char *opnames[] = {
	33	[ FILTER_OP_UNKNOWN ] = "UNKNOWN",
	34
	35	[ FILTER_OP_RETURN ] = "RETURN",
	36
	37	/* binary */
	38	[ FILTER_OP_MUL ] = "MUL",
	39	[ FILTER_OP_DIV ] = "DIV",
	40	[ FILTER_OP_MOD ] = "MOD",
	41	[ FILTER_OP_PLUS ] = "PLUS",
	42	[ FILTER_OP_MINUS ] = "MINUS",
0039e2d8 MD	43	[ FILTER_OP_BIT_RSHIFT ] = "BIT_RSHIFT",
0039e2d8 MD	44	[ FILTER_OP_BIT_LSHIFT ] = "BIT_LSHIFT",
47e5f13e MD	45	[ FILTER_OP_BIT_AND ] = "BIT_AND",
	46	[ FILTER_OP_BIT_OR ] = "BIT_OR",
	47	[ FILTER_OP_BIT_XOR ] = "BIT_XOR",
226106c0 MD	48
226106c0 MD	49	/* binary comparators */
cd54f6d9 MD	50	[ FILTER_OP_EQ ] = "EQ",
	51	[ FILTER_OP_NE ] = "NE",
	52	[ FILTER_OP_GT ] = "GT",
	53	[ FILTER_OP_LT ] = "LT",
	54	[ FILTER_OP_GE ] = "GE",
	55	[ FILTER_OP_LE ] = "LE",
	56
226106c0 MD	57	/* string binary comparators */
	58	[ FILTER_OP_EQ_STRING ] = "EQ_STRING",
	59	[ FILTER_OP_NE_STRING ] = "NE_STRING",
	60	[ FILTER_OP_GT_STRING ] = "GT_STRING",
	61	[ FILTER_OP_LT_STRING ] = "LT_STRING",
	62	[ FILTER_OP_GE_STRING ] = "GE_STRING",
	63	[ FILTER_OP_LE_STRING ] = "LE_STRING",
	64
	65	/* s64 binary comparators */
	66	[ FILTER_OP_EQ_S64 ] = "EQ_S64",
	67	[ FILTER_OP_NE_S64 ] = "NE_S64",
	68	[ FILTER_OP_GT_S64 ] = "GT_S64",
	69	[ FILTER_OP_LT_S64 ] = "LT_S64",
	70	[ FILTER_OP_GE_S64 ] = "GE_S64",
	71	[ FILTER_OP_LE_S64 ] = "LE_S64",
	72
	73	/* double binary comparators */
	74	[ FILTER_OP_EQ_DOUBLE ] = "EQ_DOUBLE",
	75	[ FILTER_OP_NE_DOUBLE ] = "NE_DOUBLE",
	76	[ FILTER_OP_GT_DOUBLE ] = "GT_DOUBLE",
	77	[ FILTER_OP_LT_DOUBLE ] = "LT_DOUBLE",
	78	[ FILTER_OP_GE_DOUBLE ] = "GE_DOUBLE",
	79	[ FILTER_OP_LE_DOUBLE ] = "LE_DOUBLE",
	80
1e5f62b4 MD	81	/* Mixed S64-double binary comparators */
	82	[ FILTER_OP_EQ_DOUBLE_S64 ] = "EQ_DOUBLE_S64",
	83	[ FILTER_OP_NE_DOUBLE_S64 ] = "NE_DOUBLE_S64",
	84	[ FILTER_OP_GT_DOUBLE_S64 ] = "GT_DOUBLE_S64",
	85	[ FILTER_OP_LT_DOUBLE_S64 ] = "LT_DOUBLE_S64",
	86	[ FILTER_OP_GE_DOUBLE_S64 ] = "GE_DOUBLE_S64",
	87	[ FILTER_OP_LE_DOUBLE_S64 ] = "LE_DOUBLE_S64",
	88
	89	[ FILTER_OP_EQ_S64_DOUBLE ] = "EQ_S64_DOUBLE",
	90	[ FILTER_OP_NE_S64_DOUBLE ] = "NE_S64_DOUBLE",
	91	[ FILTER_OP_GT_S64_DOUBLE ] = "GT_S64_DOUBLE",
	92	[ FILTER_OP_LT_S64_DOUBLE ] = "LT_S64_DOUBLE",
	93	[ FILTER_OP_GE_S64_DOUBLE ] = "GE_S64_DOUBLE",
	94	[ FILTER_OP_LE_S64_DOUBLE ] = "LE_S64_DOUBLE",
226106c0	95
cd54f6d9 MD	96	/* unary */
	97	[ FILTER_OP_UNARY_PLUS ] = "UNARY_PLUS",
	98	[ FILTER_OP_UNARY_MINUS ] = "UNARY_MINUS",
	99	[ FILTER_OP_UNARY_NOT ] = "UNARY_NOT",
226106c0 MD	100	[ FILTER_OP_UNARY_PLUS_S64 ] = "UNARY_PLUS_S64",
	101	[ FILTER_OP_UNARY_MINUS_S64 ] = "UNARY_MINUS_S64",
	102	[ FILTER_OP_UNARY_NOT_S64 ] = "UNARY_NOT_S64",
	103	[ FILTER_OP_UNARY_PLUS_DOUBLE ] = "UNARY_PLUS_DOUBLE",
	104	[ FILTER_OP_UNARY_MINUS_DOUBLE ] = "UNARY_MINUS_DOUBLE",
	105	[ FILTER_OP_UNARY_NOT_DOUBLE ] = "UNARY_NOT_DOUBLE",
cd54f6d9 MD	106
	107	/* logical */
	108	[ FILTER_OP_AND ] = "AND",
	109	[ FILTER_OP_OR ] = "OR",
	110
77aa5901	111	/* load field ref */
cd54f6d9	112	[ FILTER_OP_LOAD_FIELD_REF ] = "LOAD_FIELD_REF",
2f0145d1 MD	113	[ FILTER_OP_LOAD_FIELD_REF_STRING ] = "LOAD_FIELD_REF_STRING",
	114	[ FILTER_OP_LOAD_FIELD_REF_SEQUENCE ] = "LOAD_FIELD_REF_SEQUENCE",
	115	[ FILTER_OP_LOAD_FIELD_REF_S64 ] = "LOAD_FIELD_REF_S64",
	116	[ FILTER_OP_LOAD_FIELD_REF_DOUBLE ] = "LOAD_FIELD_REF_DOUBLE",
	117
77aa5901	118	/* load from immediate operand */
cd54f6d9 MD	119	[ FILTER_OP_LOAD_STRING ] = "LOAD_STRING",
cd54f6d9 MD	120	[ FILTER_OP_LOAD_S64 ] = "LOAD_S64",
da6eed25	121	[ FILTER_OP_LOAD_DOUBLE ] = "LOAD_DOUBLE",
49905038 MD	122
	123	/* cast */
	124	[ FILTER_OP_CAST_TO_S64 ] = "CAST_TO_S64",
	125	[ FILTER_OP_CAST_DOUBLE_TO_S64 ] = "CAST_DOUBLE_TO_S64",
	126	[ FILTER_OP_CAST_NOP ] = "CAST_NOP",
77aa5901 MD	127
	128	/* get context ref */
	129	[ FILTER_OP_GET_CONTEXT_REF ] = "GET_CONTEXT_REF",
	130	[ FILTER_OP_GET_CONTEXT_REF_STRING ] = "GET_CONTEXT_REF_STRING",
	131	[ FILTER_OP_GET_CONTEXT_REF_S64 ] = "GET_CONTEXT_REF_S64",
	132	[ FILTER_OP_GET_CONTEXT_REF_DOUBLE ] = "GET_CONTEXT_REF_DOUBLE",
f6753f2d MD	133
	134	/* load userspace field ref */
	135	[ FILTER_OP_LOAD_FIELD_REF_USER_STRING ] = "LOAD_FIELD_REF_USER_STRING",
	136	[ FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE ] = "LOAD_FIELD_REF_USER_SEQUENCE",
	137
	138	/*
	139	* load immediate star globbing pattern (literal string)
	140	* from immediate.
	141	*/
	142	[ FILTER_OP_LOAD_STAR_GLOB_STRING ] = "LOAD_STAR_GLOB_STRING",
	143
	144	/* globbing pattern binary operator: apply to */
	145	[ FILTER_OP_EQ_STAR_GLOB_STRING ] = "EQ_STAR_GLOB_STRING",
	146	[ FILTER_OP_NE_STAR_GLOB_STRING ] = "NE_STAR_GLOB_STRING",
47e5f13e MD	147
	148	/*
	149	* Instructions for recursive traversal through composed types.
	150	*/
	151	[ FILTER_OP_GET_CONTEXT_ROOT ] = "GET_CONTEXT_ROOT",
	152	[ FILTER_OP_GET_APP_CONTEXT_ROOT ] = "GET_APP_CONTEXT_ROOT",
	153	[ FILTER_OP_GET_PAYLOAD_ROOT ] = "GET_PAYLOAD_ROOT",
	154
	155	[ FILTER_OP_GET_SYMBOL ] = "GET_SYMBOL",
	156	[ FILTER_OP_GET_SYMBOL_FIELD ] = "GET_SYMBOL_FIELD",
	157	[ FILTER_OP_GET_INDEX_U16 ] = "GET_INDEX_U16",
	158	[ FILTER_OP_GET_INDEX_U64 ] = "GET_INDEX_U64",
	159
	160	[ FILTER_OP_LOAD_FIELD ] = "LOAD_FIELD",
	161	[ FILTER_OP_LOAD_FIELD_S8 ] = "LOAD_FIELD_S8",
	162	[ FILTER_OP_LOAD_FIELD_S16 ] = "LOAD_FIELD_S16",
	163	[ FILTER_OP_LOAD_FIELD_S32 ] = "LOAD_FIELD_S32",
	164	[ FILTER_OP_LOAD_FIELD_S64 ] = "LOAD_FIELD_S64",
	165	[ FILTER_OP_LOAD_FIELD_U8 ] = "LOAD_FIELD_U8",
	166	[ FILTER_OP_LOAD_FIELD_U16 ] = "LOAD_FIELD_U16",
	167	[ FILTER_OP_LOAD_FIELD_U32 ] = "LOAD_FIELD_U32",
	168	[ FILTER_OP_LOAD_FIELD_U64 ] = "LOAD_FIELD_U64",
	169	[ FILTER_OP_LOAD_FIELD_STRING ] = "LOAD_FIELD_STRING",
	170	[ FILTER_OP_LOAD_FIELD_SEQUENCE ] = "LOAD_FIELD_SEQUENCE",
	171	[ FILTER_OP_LOAD_FIELD_DOUBLE ] = "LOAD_FIELD_DOUBLE",
0039e2d8 MD	172
0039e2d8 MD	173	[ FILTER_OP_UNARY_BIT_NOT ] = "UNARY_BIT_NOT",
93c591bb MD	174
93c591bb MD	175	[ FILTER_OP_RETURN_S64 ] = "RETURN_S64",
cd54f6d9 MD	176	};
cd54f6d9 MD	177
cd54f6d9 MD	178	const char *print_op(enum filter_op op)
	179	{
	180	if (op >= NR_FILTER_OPS)
	181	return "UNKNOWN";
	182	else
	183	return opnames[op];
	184	}
	185
cd54f6d9	186	static
7dd08bec	187	int apply_field_reloc(struct lttng_event *event,
cd54f6d9 MD	188	struct bytecode_runtime *runtime,
	189	uint32_t runtime_len,
	190	uint32_t reloc_offset,
47e5f13e MD	191	const char *field_name,
47e5f13e MD	192	enum filter_op filter_op)
cd54f6d9 MD	193	{
	194	const struct lttng_event_desc *desc;
	195	const struct lttng_event_field fields, field = NULL;
	196	unsigned int nr_fields, i;
2f0145d1	197	struct load_op *op;
cd54f6d9 MD	198	uint32_t field_offset = 0;
cd54f6d9 MD	199
77aa5901	200	dbg_printf("Apply field reloc: %u %s\n", reloc_offset, field_name);
cd54f6d9 MD	201
	202	/* Lookup event by name */
	203	desc = event->desc;
	204	if (!desc)
	205	return -EINVAL;
	206	fields = desc->fields;
	207	if (!fields)
	208	return -EINVAL;
	209	nr_fields = desc->nr_fields;
	210	for (i = 0; i < nr_fields; i++) {
	211	if (!strcmp(fields[i].name, field_name)) {
	212	field = &fields[i];
	213	break;
	214	}
	215	/* compute field offset */
	216	switch (fields[i].type.atype) {
	217	case atype_integer:
	218	case atype_enum:
	219	field_offset += sizeof(int64_t);
	220	break;
	221	case atype_array:
	222	case atype_sequence:
	223	field_offset += sizeof(unsigned long);
	224	field_offset += sizeof(void *);
	225	break;
	226	case atype_string:
	227	field_offset += sizeof(void *);
	228	break;
	229	case atype_float:
	230	field_offset += sizeof(double);
da6eed25	231	break;
cd54f6d9 MD	232	default:
	233	return -EINVAL;
	234	}
	235	}
	236	if (!field)
	237	return -EINVAL;
	238
	239	/* Check if field offset is too large for 16-bit offset */
5b4839a8	240	if (field_offset > FILTER_BYTECODE_MAX_LEN - 1)
cd54f6d9 MD	241	return -EINVAL;
	242
	243	/* set type */
47e5f13e MD	244	op = (struct load_op *) &runtime->code[reloc_offset];
	245
	246	switch (filter_op) {
	247	case FILTER_OP_LOAD_FIELD_REF:
	248	{
	249	struct field_ref *field_ref;
	250
	251	field_ref = (struct field_ref *) op->data;
	252	switch (field->type.atype) {
	253	case atype_integer:
	254	case atype_enum:
	255	op->op = FILTER_OP_LOAD_FIELD_REF_S64;
	256	break;
	257	case atype_array:
	258	case atype_sequence:
	259	op->op = FILTER_OP_LOAD_FIELD_REF_SEQUENCE;
	260	break;
	261	case atype_string:
	262	op->op = FILTER_OP_LOAD_FIELD_REF_STRING;
	263	break;
	264	case atype_float:
	265	op->op = FILTER_OP_LOAD_FIELD_REF_DOUBLE;
	266	break;
	267	default:
	268	return -EINVAL;
	269	}
	270	/* set offset */
	271	field_ref->offset = (uint16_t) field_offset;
da6eed25	272	break;
47e5f13e	273	}
cd54f6d9 MD	274	default:
	275	return -EINVAL;
	276	}
2d78951a MD	277	return 0;
	278	}
	279
77aa5901 MD	280	static
	281	int apply_context_reloc(struct lttng_event *event,
	282	struct bytecode_runtime *runtime,
	283	uint32_t runtime_len,
	284	uint32_t reloc_offset,
47e5f13e MD	285	const char *context_name,
47e5f13e MD	286	enum filter_op filter_op)
77aa5901	287	{
77aa5901 MD	288	struct load_op *op;
	289	struct lttng_ctx_field *ctx_field;
	290	int idx;
53569322	291	struct lttng_session *session = runtime->p.session;
77aa5901 MD	292
	293	dbg_printf("Apply context reloc: %u %s\n", reloc_offset, context_name);
	294
	295	/* Get context index */
53569322 MD	296	idx = lttng_get_context_index(session->ctx, context_name);
	297	if (idx < 0) {
	298	if (lttng_context_is_app(context_name)) {
	299	int ret;
	300
	301	ret = lttng_ust_add_app_context_to_ctx_rcu(context_name,
	302	&session->ctx);
	303	if (ret)
	304	return ret;
	305	idx = lttng_get_context_index(session->ctx,
	306	context_name);
	307	if (idx < 0)
	308	return -ENOENT;
	309	} else {
	310	return -ENOENT;
	311	}
	312	}
77aa5901 MD	313	/* Check if idx is too large for 16-bit offset */
	314	if (idx > FILTER_BYTECODE_MAX_LEN - 1)
	315	return -EINVAL;
	316
	317	/* Get context return type */
53569322	318	ctx_field = &session->ctx->fields[idx];
47e5f13e MD	319	op = (struct load_op *) &runtime->code[reloc_offset];
	320
	321	switch (filter_op) {
	322	case FILTER_OP_GET_CONTEXT_REF:
	323	{
	324	struct field_ref *field_ref;
	325
	326	field_ref = (struct field_ref *) op->data;
	327	switch (ctx_field->event_field.type.atype) {
	328	case atype_integer:
	329	case atype_enum:
	330	op->op = FILTER_OP_GET_CONTEXT_REF_S64;
	331	break;
	332	/* Sequence and array supported as string */
	333	case atype_string:
	334	case atype_array:
	335	case atype_sequence:
	336	op->op = FILTER_OP_GET_CONTEXT_REF_STRING;
	337	break;
	338	case atype_float:
	339	op->op = FILTER_OP_GET_CONTEXT_REF_DOUBLE;
	340	break;
	341	case atype_dynamic:
	342	op->op = FILTER_OP_GET_CONTEXT_REF;
	343	break;
	344	default:
	345	return -EINVAL;
	346	}
	347	/* set offset to context index within channel contexts */
	348	field_ref->offset = (uint16_t) idx;
53569322	349	break;
47e5f13e	350	}
77aa5901 MD	351	default:
	352	return -EINVAL;
	353	}
77aa5901 MD	354	return 0;
	355	}
	356
	357	static
	358	int apply_reloc(struct lttng_event *event,
	359	struct bytecode_runtime *runtime,
	360	uint32_t runtime_len,
	361	uint32_t reloc_offset,
	362	const char *name)
	363	{
	364	struct load_op *op;
	365
	366	dbg_printf("Apply reloc: %u %s\n", reloc_offset, name);
	367
	368	/* Ensure that the reloc is within the code */
	369	if (runtime_len - reloc_offset < sizeof(uint16_t))
	370	return -EINVAL;
	371
47e5f13e	372	op = (struct load_op *) &runtime->code[reloc_offset];
77aa5901 MD	373	switch (op->op) {
	374	case FILTER_OP_LOAD_FIELD_REF:
	375	return apply_field_reloc(event, runtime, runtime_len,
47e5f13e	376	reloc_offset, name, op->op);
77aa5901 MD	377	case FILTER_OP_GET_CONTEXT_REF:
77aa5901 MD	378	return apply_context_reloc(event, runtime, runtime_len,
47e5f13e MD	379	reloc_offset, name, op->op);
	380	case FILTER_OP_GET_SYMBOL:
	381	case FILTER_OP_GET_SYMBOL_FIELD:
	382	/*
	383	* Will be handled by load specialize phase or
	384	* dynamically by interpreter.
	385	*/
	386	return 0;
77aa5901 MD	387	default:
	388	ERR("Unknown reloc op type %u\n", op->op);
	389	return -EINVAL;
	390	}
	391	return 0;
	392	}
	393
f488575f MD	394	static
f488575f MD	395	int bytecode_is_linked(struct lttng_ust_filter_bytecode_node *filter_bytecode,
7dd08bec	396	struct lttng_event *event)
f488575f MD	397	{
	398	struct lttng_bytecode_runtime *bc_runtime;
	399
e58095ef MD	400	cds_list_for_each_entry(bc_runtime,
e58095ef MD	401	&event->bytecode_runtime_head, node) {
f488575f MD	402	if (bc_runtime->bc == filter_bytecode)
	403	return 1;
	404	}
	405	return 0;
	406	}
	407
cd54f6d9 MD	408	/*
	409	* Take a bytecode with reloc table and link it to an event to create a
	410	* bytecode runtime.
	411	*/
2d78951a	412	static
7dd08bec	413	int _lttng_filter_event_link_bytecode(struct lttng_event *event,
e58095ef MD	414	struct lttng_ust_filter_bytecode_node *filter_bytecode,
e58095ef MD	415	struct cds_list_head *insert_loc)
2d78951a	416	{
cd54f6d9 MD	417	int ret, offset, next_offset;
	418	struct bytecode_runtime *runtime = NULL;
	419	size_t runtime_alloc_len;
	420
2d78951a MD	421	if (!filter_bytecode)
2d78951a MD	422	return 0;
cd54f6d9	423	/* Bytecode already linked */
f488575f	424	if (bytecode_is_linked(filter_bytecode, event))
cd54f6d9	425	return 0;
2d78951a	426
f488575f	427	dbg_printf("Linking...\n");
cd54f6d9 MD	428
cd54f6d9 MD	429	/* We don't need the reloc table in the runtime */
f488575f	430	runtime_alloc_len = sizeof(*runtime) + filter_bytecode->bc.reloc_offset;
cd54f6d9 MD	431	runtime = zmalloc(runtime_alloc_len);
	432	if (!runtime) {
	433	ret = -ENOMEM;
e0a7d7ab	434	goto alloc_error;
cd54f6d9	435	}
f488575f	436	runtime->p.bc = filter_bytecode;
53569322	437	runtime->p.session = event->chan->session;
47e5f13e	438	runtime->p.event = event;
f488575f	439	runtime->len = filter_bytecode->bc.reloc_offset;
cd54f6d9	440	/* copy original bytecode */
47e5f13e	441	memcpy(runtime->code, filter_bytecode->bc.data, runtime->len);
cd54f6d9 MD	442	/*
	443	* apply relocs. Those are a uint16_t (offset in bytecode)
	444	* followed by a string (field name).
	445	*/
f488575f MD	446	for (offset = filter_bytecode->bc.reloc_offset;
f488575f MD	447	offset < filter_bytecode->bc.len;
cd54f6d9 MD	448	offset = next_offset) {
cd54f6d9 MD	449	uint16_t reloc_offset =
f488575f	450	(uint16_t ) &filter_bytecode->bc.data[offset];
77aa5901	451	const char *name =
f488575f	452	(const char *) &filter_bytecode->bc.data[offset + sizeof(uint16_t)];
cd54f6d9	453
77aa5901	454	ret = apply_reloc(event, runtime, runtime->len, reloc_offset, name);
cd54f6d9 MD	455	if (ret) {
	456	goto link_error;
	457	}
77aa5901	458	next_offset = offset + sizeof(uint16_t) + strlen(name) + 1;
cd54f6d9	459	}
9522a886 MD	460	/* Validate bytecode */
	461	ret = lttng_filter_validate_bytecode(runtime);
	462	if (ret) {
	463	goto link_error;
	464	}
08c84b15	465	/* Specialize bytecode */
47e5f13e	466	ret = lttng_filter_specialize_bytecode(event, runtime);
08c84b15 MD	467	if (ret) {
	468	goto link_error;
	469	}
f488575f	470	runtime->p.filter = lttng_filter_interpret_bytecode;
21af05a9	471	runtime->p.link_failed = 0;
e58095ef	472	cds_list_add_rcu(&runtime->p.node, insert_loc);
f488575f	473	dbg_printf("Linking successful.\n");
2d78951a	474	return 0;
cd54f6d9 MD	475
cd54f6d9 MD	476	link_error:
f488575f	477	runtime->p.filter = lttng_filter_false;
21af05a9	478	runtime->p.link_failed = 1;
e58095ef	479	cds_list_add_rcu(&runtime->p.node, insert_loc);
e0a7d7ab	480	alloc_error:
f488575f	481	dbg_printf("Linking failed.\n");
cd54f6d9	482	return ret;
2d78951a MD	483	}
2d78951a MD	484
e58095ef	485	void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime)
2d78951a	486	{
e58095ef	487	struct lttng_ust_filter_bytecode_node *bc = runtime->bc;
f488575f	488
21af05a9	489	if (!bc->enabler->enabled \|\| runtime->link_failed)
e58095ef	490	runtime->filter = lttng_filter_false;
21af05a9 MD	491	else
21af05a9 MD	492	runtime->filter = lttng_filter_interpret_bytecode;
2d78951a MD	493	}
	494
	495	/*
e58095ef	496	* Link bytecode for all enablers referenced by an event.
2d78951a	497	*/
e58095ef MD	498	void lttng_enabler_event_link_bytecode(struct lttng_event *event,
e58095ef MD	499	struct lttng_enabler *enabler)
2d78951a	500	{
e58095ef MD	501	struct lttng_ust_filter_bytecode_node *bc;
	502	struct lttng_bytecode_runtime *runtime;
	503
	504	/* Can only be called for events with desc attached */
	505	assert(event->desc);
	506
	507	/* Link each bytecode. */
	508	cds_list_for_each_entry(bc, &enabler->filter_bytecode_head, node) {
	509	int found = 0, ret;
	510	struct cds_list_head *insert_loc;
	511
	512	cds_list_for_each_entry(runtime,
	513	&event->bytecode_runtime_head, node) {
	514	if (runtime->bc == bc) {
	515	found = 1;
	516	break;
	517	}
	518	}
	519	/* Skip bytecode already linked */
	520	if (found)
	521	continue;
	522
	523	/*
	524	* Insert at specified priority (seqnum) in increasing
	525	* order.
	526	*/
	527	cds_list_for_each_entry_reverse(runtime,
	528	&event->bytecode_runtime_head, node) {
	529	if (runtime->bc->bc.seqnum < bc->bc.seqnum) {
	530	/* insert here */
	531	insert_loc = &runtime->node;
	532	goto add_within;
	533	}
	534	}
	535	/* Add to head to list */
	536	insert_loc = &event->bytecode_runtime_head;
	537	add_within:
f488575f	538	dbg_printf("linking bytecode\n");
e58095ef MD	539	ret = _lttng_filter_event_link_bytecode(event, bc,
	540	insert_loc);
	541	if (ret) {
	542	dbg_printf("[lttng filter] warning: cannot link event bytecode\n");
	543	}
2d78951a	544	}
2d78951a MD	545	}
	546
	547	/*
e58095ef	548	* We own the filter_bytecode if we return success.
2d78951a	549	*/
e58095ef	550	int lttng_filter_enabler_attach_bytecode(struct lttng_enabler *enabler,
f488575f	551	struct lttng_ust_filter_bytecode_node *filter_bytecode)
2d78951a	552	{
e58095ef	553	cds_list_add(&filter_bytecode->node, &enabler->filter_bytecode_head);
2d78951a MD	554	return 0;
2d78951a MD	555	}
f488575f	556
e58095ef	557	void lttng_free_enabler_filter_bytecode(struct lttng_enabler *enabler)
f488575f MD	558	{
	559	struct lttng_ust_filter_bytecode_node filter_bytecode, tmp;
	560
	561	cds_list_for_each_entry_safe(filter_bytecode, tmp,
e58095ef	562	&enabler->filter_bytecode_head, node) {
f488575f MD	563	free(filter_bytecode);
	564	}
	565	}
	566
7dd08bec	567	void lttng_free_event_filter_runtime(struct lttng_event *event)
f488575f MD	568	{
	569	struct bytecode_runtime runtime, tmp;
	570
	571	cds_list_for_each_entry_safe(runtime, tmp,
e58095ef	572	&event->bytecode_runtime_head, p.node) {
47e5f13e	573	free(runtime->data);
f488575f MD	574	free(runtime);
	575	}
	576	}