[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 <stdint.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>
fb31eb73 FD	29	#include <stdint.h>
fb31eb73 FD	30
f488575f	31	#include <urcu/rculist.h>
fb31eb73	32
97b58163	33	#include "lttng-filter.h"
cd54f6d9 MD	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",
0039e2d8 MD	46	[ FILTER_OP_BIT_RSHIFT ] = "BIT_RSHIFT",
0039e2d8 MD	47	[ FILTER_OP_BIT_LSHIFT ] = "BIT_LSHIFT",
47e5f13e MD	48	[ FILTER_OP_BIT_AND ] = "BIT_AND",
	49	[ FILTER_OP_BIT_OR ] = "BIT_OR",
	50	[ FILTER_OP_BIT_XOR ] = "BIT_XOR",
226106c0 MD	51
226106c0 MD	52	/* binary comparators */
cd54f6d9 MD	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
226106c0 MD	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
1e5f62b4 MD	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",
226106c0	98
cd54f6d9 MD	99	/* unary */
	100	[ FILTER_OP_UNARY_PLUS ] = "UNARY_PLUS",
	101	[ FILTER_OP_UNARY_MINUS ] = "UNARY_MINUS",
	102	[ FILTER_OP_UNARY_NOT ] = "UNARY_NOT",
226106c0 MD	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",
cd54f6d9 MD	109
	110	/* logical */
	111	[ FILTER_OP_AND ] = "AND",
	112	[ FILTER_OP_OR ] = "OR",
	113
77aa5901	114	/* load field ref */
cd54f6d9	115	[ FILTER_OP_LOAD_FIELD_REF ] = "LOAD_FIELD_REF",
2f0145d1 MD	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
77aa5901	121	/* load from immediate operand */
cd54f6d9 MD	122	[ FILTER_OP_LOAD_STRING ] = "LOAD_STRING",
cd54f6d9 MD	123	[ FILTER_OP_LOAD_S64 ] = "LOAD_S64",
da6eed25	124	[ FILTER_OP_LOAD_DOUBLE ] = "LOAD_DOUBLE",
49905038 MD	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",
77aa5901 MD	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",
f6753f2d MD	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",
47e5f13e MD	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",
0039e2d8 MD	175
0039e2d8 MD	176	[ FILTER_OP_UNARY_BIT_NOT ] = "UNARY_BIT_NOT",
93c591bb MD	177
93c591bb MD	178	[ FILTER_OP_RETURN_S64 ] = "RETURN_S64",
cd54f6d9 MD	179	};
cd54f6d9 MD	180
cd54f6d9 MD	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
cd54f6d9	189	static
7dd08bec	190	int apply_field_reloc(struct lttng_event *event,
cd54f6d9 MD	191	struct bytecode_runtime *runtime,
	192	uint32_t runtime_len,
	193	uint32_t reloc_offset,
47e5f13e MD	194	const char *field_name,
47e5f13e MD	195	enum filter_op filter_op)
cd54f6d9 MD	196	{
	197	const struct lttng_event_desc *desc;
	198	const struct lttng_event_field fields, field = NULL;
	199	unsigned int nr_fields, i;
2f0145d1	200	struct load_op *op;
cd54f6d9 MD	201	uint32_t field_offset = 0;
cd54f6d9 MD	202
77aa5901	203	dbg_printf("Apply field reloc: %u %s\n", reloc_offset, field_name);
cd54f6d9 MD	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);
da6eed25	234	break;
cd54f6d9 MD	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 */
5b4839a8	243	if (field_offset > FILTER_BYTECODE_MAX_LEN - 1)
cd54f6d9 MD	244	return -EINVAL;
	245
	246	/* set type */
47e5f13e MD	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;
da6eed25	275	break;
47e5f13e	276	}
cd54f6d9 MD	277	default:
	278	return -EINVAL;
	279	}
2d78951a MD	280	return 0;
	281	}
	282
77aa5901 MD	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,
47e5f13e MD	288	const char *context_name,
47e5f13e MD	289	enum filter_op filter_op)
77aa5901	290	{
77aa5901 MD	291	struct load_op *op;
	292	struct lttng_ctx_field *ctx_field;
	293	int idx;
53569322	294	struct lttng_session *session = runtime->p.session;
77aa5901 MD	295
	296	dbg_printf("Apply context reloc: %u %s\n", reloc_offset, context_name);
	297
	298	/* Get context index */
53569322 MD	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	}
77aa5901 MD	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 */
53569322	321	ctx_field = &session->ctx->fields[idx];
47e5f13e MD	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;
53569322	352	break;
47e5f13e	353	}
77aa5901 MD	354	default:
	355	return -EINVAL;
	356	}
77aa5901 MD	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
47e5f13e	375	op = (struct load_op *) &runtime->code[reloc_offset];
77aa5901 MD	376	switch (op->op) {
	377	case FILTER_OP_LOAD_FIELD_REF:
	378	return apply_field_reloc(event, runtime, runtime_len,
47e5f13e	379	reloc_offset, name, op->op);
77aa5901 MD	380	case FILTER_OP_GET_CONTEXT_REF:
77aa5901 MD	381	return apply_context_reloc(event, runtime, runtime_len,
47e5f13e MD	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;
77aa5901 MD	390	default:
	391	ERR("Unknown reloc op type %u\n", op->op);
	392	return -EINVAL;
	393	}
	394	return 0;
	395	}
	396
f488575f MD	397	static
f488575f MD	398	int bytecode_is_linked(struct lttng_ust_filter_bytecode_node *filter_bytecode,
7dd08bec	399	struct lttng_event *event)
f488575f MD	400	{
	401	struct lttng_bytecode_runtime *bc_runtime;
	402
e58095ef MD	403	cds_list_for_each_entry(bc_runtime,
e58095ef MD	404	&event->bytecode_runtime_head, node) {
f488575f MD	405	if (bc_runtime->bc == filter_bytecode)
	406	return 1;
	407	}
	408	return 0;
	409	}
	410
cd54f6d9 MD	411	/*
	412	* Take a bytecode with reloc table and link it to an event to create a
	413	* bytecode runtime.
	414	*/
2d78951a	415	static
7dd08bec	416	int _lttng_filter_event_link_bytecode(struct lttng_event *event,
e58095ef MD	417	struct lttng_ust_filter_bytecode_node *filter_bytecode,
e58095ef MD	418	struct cds_list_head *insert_loc)
2d78951a	419	{
cd54f6d9 MD	420	int ret, offset, next_offset;
	421	struct bytecode_runtime *runtime = NULL;
	422	size_t runtime_alloc_len;
	423
2d78951a MD	424	if (!filter_bytecode)
2d78951a MD	425	return 0;
cd54f6d9	426	/* Bytecode already linked */
f488575f	427	if (bytecode_is_linked(filter_bytecode, event))
cd54f6d9	428	return 0;
2d78951a	429
f488575f	430	dbg_printf("Linking...\n");
cd54f6d9 MD	431
cd54f6d9 MD	432	/* We don't need the reloc table in the runtime */
f488575f	433	runtime_alloc_len = sizeof(*runtime) + filter_bytecode->bc.reloc_offset;
cd54f6d9 MD	434	runtime = zmalloc(runtime_alloc_len);
	435	if (!runtime) {
	436	ret = -ENOMEM;
e0a7d7ab	437	goto alloc_error;
cd54f6d9	438	}
f488575f	439	runtime->p.bc = filter_bytecode;
53569322	440	runtime->p.session = event->chan->session;
47e5f13e	441	runtime->p.event = event;
f488575f	442	runtime->len = filter_bytecode->bc.reloc_offset;
cd54f6d9	443	/* copy original bytecode */
47e5f13e	444	memcpy(runtime->code, filter_bytecode->bc.data, runtime->len);
cd54f6d9 MD	445	/*
	446	* apply relocs. Those are a uint16_t (offset in bytecode)
	447	* followed by a string (field name).
	448	*/
f488575f MD	449	for (offset = filter_bytecode->bc.reloc_offset;
f488575f MD	450	offset < filter_bytecode->bc.len;
cd54f6d9 MD	451	offset = next_offset) {
cd54f6d9 MD	452	uint16_t reloc_offset =
f488575f	453	(uint16_t ) &filter_bytecode->bc.data[offset];
77aa5901	454	const char *name =
f488575f	455	(const char *) &filter_bytecode->bc.data[offset + sizeof(uint16_t)];
cd54f6d9	456
77aa5901	457	ret = apply_reloc(event, runtime, runtime->len, reloc_offset, name);
cd54f6d9 MD	458	if (ret) {
	459	goto link_error;
	460	}
77aa5901	461	next_offset = offset + sizeof(uint16_t) + strlen(name) + 1;
cd54f6d9	462	}
9522a886 MD	463	/* Validate bytecode */
	464	ret = lttng_filter_validate_bytecode(runtime);
	465	if (ret) {
	466	goto link_error;
	467	}
08c84b15	468	/* Specialize bytecode */
47e5f13e	469	ret = lttng_filter_specialize_bytecode(event, runtime);
08c84b15 MD	470	if (ret) {
	471	goto link_error;
	472	}
f488575f	473	runtime->p.filter = lttng_filter_interpret_bytecode;
21af05a9	474	runtime->p.link_failed = 0;
e58095ef	475	cds_list_add_rcu(&runtime->p.node, insert_loc);
f488575f	476	dbg_printf("Linking successful.\n");
2d78951a	477	return 0;
cd54f6d9 MD	478
cd54f6d9 MD	479	link_error:
f488575f	480	runtime->p.filter = lttng_filter_false;
21af05a9	481	runtime->p.link_failed = 1;
e58095ef	482	cds_list_add_rcu(&runtime->p.node, insert_loc);
e0a7d7ab	483	alloc_error:
f488575f	484	dbg_printf("Linking failed.\n");
cd54f6d9	485	return ret;
2d78951a MD	486	}
2d78951a MD	487
e58095ef	488	void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime)
2d78951a	489	{
e58095ef	490	struct lttng_ust_filter_bytecode_node *bc = runtime->bc;
f488575f	491
21af05a9	492	if (!bc->enabler->enabled \|\| runtime->link_failed)
e58095ef	493	runtime->filter = lttng_filter_false;
21af05a9 MD	494	else
21af05a9 MD	495	runtime->filter = lttng_filter_interpret_bytecode;
2d78951a MD	496	}
	497
	498	/*
e58095ef	499	* Link bytecode for all enablers referenced by an event.
2d78951a	500	*/
e58095ef MD	501	void lttng_enabler_event_link_bytecode(struct lttng_event *event,
e58095ef MD	502	struct lttng_enabler *enabler)
2d78951a	503	{
e58095ef MD	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:
f488575f	541	dbg_printf("linking bytecode\n");
e58095ef MD	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	}
2d78951a	547	}
2d78951a MD	548	}
	549
	550	/*
e58095ef	551	* We own the filter_bytecode if we return success.
2d78951a	552	*/
e58095ef	553	int lttng_filter_enabler_attach_bytecode(struct lttng_enabler *enabler,
f488575f	554	struct lttng_ust_filter_bytecode_node *filter_bytecode)
2d78951a	555	{
e58095ef	556	cds_list_add(&filter_bytecode->node, &enabler->filter_bytecode_head);
2d78951a MD	557	return 0;
2d78951a MD	558	}
f488575f	559
e58095ef	560	void lttng_free_enabler_filter_bytecode(struct lttng_enabler *enabler)
f488575f MD	561	{
	562	struct lttng_ust_filter_bytecode_node filter_bytecode, tmp;
	563
	564	cds_list_for_each_entry_safe(filter_bytecode, tmp,
e58095ef	565	&enabler->filter_bytecode_head, node) {
f488575f MD	566	free(filter_bytecode);
	567	}
	568	}
	569
7dd08bec	570	void lttng_free_event_filter_runtime(struct lttng_event *event)
f488575f MD	571	{
	572	struct bytecode_runtime runtime, tmp;
	573
	574	cds_list_for_each_entry_safe(runtime, tmp,
e58095ef	575	&event->bytecode_runtime_head, p.node) {
47e5f13e	576	free(runtime->data);
f488575f MD	577	free(runtime);
	578	}
	579	}