Example #1
0
/********************************************************************//**
Test and dump block metadata to dump file if necessary. */
UNIV_INTERN
void
fc_flush_test_and_dump_blkmeta(
/*==========================*/
	ulint last_time) /*!< in: the last time when
						dump the block metadata */
{
	ulint curr_time = 0;

	curr_time = ut_time_ms();
	if (((curr_time - FLASH_CACHE_DUMP_BLOCK_META_PERIOD) > last_time)) {
		/*FIXME: seal with a function*/
		flash_cache_mutex_enter();
		rw_lock_s_lock(&fc->hash_rwlock);
		fc_dump();
		rw_lock_s_unlock(&fc->hash_rwlock);
		
		flash_cache_log_mutex_enter();
		fc_log_update(FALSE, FLASH_CACHE_LOG_UPDATE_DUMP);
		fc_log_update_commit_status();
		
		flash_cache_mutex_exit();
	
		fc_log_commit();
		flash_cache_log_mutex_exit();

		srv_fc_flush_last_dump = ut_time_ms();
	}
}
Example #2
0
/*******************************************************************//**
Issue a shared/read lock on the tables cache. */
UNIV_INTERN
void
trx_i_s_cache_start_read(
/*=====================*/
	trx_i_s_cache_t*	cache)	/*!< in: cache */
{
	rw_lock_s_lock(&cache->rw_lock);
}
Example #3
0
/*************************************************************************
Checks if possible foreign key constraints hold after a delete of the record
under pcur. NOTE that this function will temporarily commit mtr and lose
pcur position! */
static
ulint
row_upd_check_references_constraints(
/*=================================*/
				/* out: DB_SUCCESS, DB_LOCK_WAIT, or an error
				code */
	btr_pcur_t*	pcur,	/* in: cursor positioned on a record; NOTE: the
				cursor position is lost in this function! */
	dict_table_t*	table,	/* in: table in question */
	dict_index_t*	index,	/* in: index of the cursor */
	que_thr_t*	thr,	/* in: query thread */
	mtr_t*		mtr)	/* in: mtr */
{
	dict_foreign_t*	foreign;
	mem_heap_t*	heap;
	dtuple_t*	entry;
	rec_t*		rec;
	ulint		err;

	rec = btr_pcur_get_rec(pcur);

	heap = mem_heap_create(500);

	entry = row_rec_to_index_entry(ROW_COPY_DATA, index, rec, heap);

	mtr_commit(mtr);	

	mtr_start(mtr);	
	
	rw_lock_s_lock(&dict_foreign_key_check_lock);	

	foreign = UT_LIST_GET_FIRST(table->referenced_list);

	while (foreign) {
		if (foreign->referenced_index == index) {

			err = row_ins_check_foreign_constraint(FALSE, foreign,
						table, index, entry, thr);
			if (err != DB_SUCCESS) {
				rw_lock_s_unlock(&dict_foreign_key_check_lock);	
				mem_heap_free(heap);

				return(err);
			}
		}

		foreign = UT_LIST_GET_NEXT(referenced_list, foreign);
	}

	rw_lock_s_unlock(&dict_foreign_key_check_lock);	
	mem_heap_free(heap);
	
	return(DB_SUCCESS);
}
Example #4
0
/*****************************************************************//**
Returns the value of ref_count. The value is protected by
btr_search_latch.
@return	ref_count value. */
UNIV_INTERN
ulint
btr_search_info_get_ref_count(
/*==========================*/
	btr_search_t*   info)	/*!< in: search info. */
{
	ulint ret;

	ut_ad(info);

#ifdef UNIV_SYNC_DEBUG
	ut_ad(!rw_lock_own(&btr_search_latch, RW_LOCK_SHARED));
	ut_ad(!rw_lock_own(&btr_search_latch, RW_LOCK_EX));
#endif /* UNIV_SYNC_DEBUG */

	rw_lock_s_lock(&btr_search_latch);
	ret = info->ref_count;
	rw_lock_s_unlock(&btr_search_latch);

	return(ret);
}
Example #5
0
/********************************************************************//**
Applies linear read-ahead if in the buf_pool the page is a border page of
a linear read-ahead area and all the pages in the area have been accessed.
Does not read any page if the read-ahead mechanism is not activated. Note
that the algorithm looks at the 'natural' adjacent successor and
predecessor of the page, which on the leaf level of a B-tree are the next
and previous page in the chain of leaves. To know these, the page specified
in (space, offset) must already be present in the buf_pool. Thus, the
natural way to use this function is to call it when a page in the buf_pool
is accessed the first time, calling this function just after it has been
bufferfixed.
NOTE 1: as this function looks at the natural predecessor and successor
fields on the page, what happens, if these are not initialized to any
sensible value? No problem, before applying read-ahead we check that the
area to read is within the span of the space, if not, read-ahead is not
applied. An uninitialized value may result in a useless read operation, but
only very improbably.
NOTE 2: the calling thread may own latches on pages: to avoid deadlocks this
function must be written such that it cannot end up waiting for these
latches!
NOTE 3: the calling thread must want access to the page given: this rule is
set to prevent unintended read-aheads performed by ibuf routines, a situation
which could result in a deadlock if the OS does not support asynchronous io.
@return	number of page read requests issued */
UNIV_INTERN
ulint
buf_read_ahead_linear(
/*==================*/
	ulint	space,		/*!< in: space id */
	ulint	zip_size,	/*!< in: compressed page size in bytes, or 0 */
	ulint	offset,		/*!< in: page number; see NOTE 3 above */
	ibool	inside_ibuf,	/*!< in: TRUE if we are inside ibuf routine */
	trx_t*	trx)
{
	buf_pool_t*	buf_pool = buf_pool_get(space, offset);
	ib_int64_t	tablespace_version;
	buf_page_t*	bpage;
	buf_frame_t*	frame;
	buf_page_t*	pred_bpage	= NULL;
	ulint		pred_offset;
	ulint		succ_offset;
	ulint		count;
	int		asc_or_desc;
	ulint		new_offset;
	ulint		fail_count;
	ulint		ibuf_mode;
	ulint		low, high;
	ulint		err;
	ulint		i;
	const ulint	buf_read_ahead_linear_area
		= BUF_READ_AHEAD_AREA(buf_pool);
	ulint		threshold;

	if (!(srv_read_ahead & 2)) {
		return(0);
	}

	if (UNIV_UNLIKELY(srv_startup_is_before_trx_rollback_phase)) {
		/* No read-ahead to avoid thread deadlocks */
		return(0);
	}

	low  = (offset / buf_read_ahead_linear_area)
		* buf_read_ahead_linear_area;
	high = (offset / buf_read_ahead_linear_area + 1)
		* buf_read_ahead_linear_area;

	if ((offset != low) && (offset != high - 1)) {
		/* This is not a border page of the area: return */

		return(0);
	}

	if (ibuf_bitmap_page(zip_size, offset)
	    || trx_sys_hdr_page(space, offset)) {

		/* If it is an ibuf bitmap page or trx sys hdr, we do
		no read-ahead, as that could break the ibuf page access
		order */

		return(0);
	}

	/* Remember the tablespace version before we ask te tablespace size
	below: if DISCARD + IMPORT changes the actual .ibd file meanwhile, we
	do not try to read outside the bounds of the tablespace! */

	tablespace_version = fil_space_get_version(space);

	buf_pool_mutex_enter(buf_pool);

	if (high > fil_space_get_size(space)) {
		buf_pool_mutex_exit(buf_pool);
		/* The area is not whole, return */

		return(0);
	}

	if (buf_pool->n_pend_reads
	    > buf_pool->curr_size / BUF_READ_AHEAD_PEND_LIMIT) {
		buf_pool_mutex_exit(buf_pool);

		return(0);
	}
	buf_pool_mutex_exit(buf_pool);

	/* Check that almost all pages in the area have been accessed; if
	offset == low, the accesses must be in a descending order, otherwise,
	in an ascending order. */

	asc_or_desc = 1;

	if (offset == low) {
		asc_or_desc = -1;
	}

	/* How many out of order accessed pages can we ignore
	when working out the access pattern for linear readahead */
	threshold = ut_min((64 - srv_read_ahead_threshold),
			   BUF_READ_AHEAD_AREA(buf_pool));

	fail_count = 0;

	rw_lock_s_lock(&buf_pool->page_hash_latch);
	for (i = low; i < high; i++) {
		bpage = buf_page_hash_get(buf_pool, space, i);

		if (bpage == NULL || !buf_page_is_accessed(bpage)) {
			/* Not accessed */
			fail_count++;

		} else if (pred_bpage) {
			/* Note that buf_page_is_accessed() returns
			the time of the first access.  If some blocks
			of the extent existed in the buffer pool at
			the time of a linear access pattern, the first
			access times may be nonmonotonic, even though
			the latest access times were linear.  The
			threshold (srv_read_ahead_factor) should help
			a little against this. */
			int res = ut_ulint_cmp(
				buf_page_is_accessed(bpage),
				buf_page_is_accessed(pred_bpage));
			/* Accesses not in the right order */
			if (res != 0 && res != asc_or_desc) {
				fail_count++;
			}
		}

		if (fail_count > threshold) {
			/* Too many failures: return */
			//buf_pool_mutex_exit(buf_pool);
			rw_lock_s_unlock(&buf_pool->page_hash_latch);
			return(0);
		}

		if (bpage && buf_page_is_accessed(bpage)) {
			pred_bpage = bpage;
		}
	}

	/* If we got this far, we know that enough pages in the area have
	been accessed in the right order: linear read-ahead can be sensible */

	bpage = buf_page_hash_get(buf_pool, space, offset);

	if (bpage == NULL) {
		//buf_pool_mutex_exit(buf_pool);
		rw_lock_s_unlock(&buf_pool->page_hash_latch);

		return(0);
	}

	switch (buf_page_get_state(bpage)) {
	case BUF_BLOCK_ZIP_PAGE:
		frame = bpage->zip.data;
		break;
	case BUF_BLOCK_FILE_PAGE:
		frame = ((buf_block_t*) bpage)->frame;
		break;
	default:
		ut_error;
		break;
	}

	/* Read the natural predecessor and successor page addresses from
	the page; NOTE that because the calling thread may have an x-latch
	on the page, we do not acquire an s-latch on the page, this is to
	prevent deadlocks. Even if we read values which are nonsense, the
	algorithm will work. */

	pred_offset = fil_page_get_prev(frame);
	succ_offset = fil_page_get_next(frame);

	//buf_pool_mutex_exit(buf_pool);
	rw_lock_s_unlock(&buf_pool->page_hash_latch);

	if ((offset == low) && (succ_offset == offset + 1)) {

		/* This is ok, we can continue */
		new_offset = pred_offset;

	} else if ((offset == high - 1) && (pred_offset == offset - 1)) {

		/* This is ok, we can continue */
		new_offset = succ_offset;
	} else {
		/* Successor or predecessor not in the right order */

		return(0);
	}

	low  = (new_offset / buf_read_ahead_linear_area)
		* buf_read_ahead_linear_area;
	high = (new_offset / buf_read_ahead_linear_area + 1)
		* buf_read_ahead_linear_area;

	if ((new_offset != low) && (new_offset != high - 1)) {
		/* This is not a border page of the area: return */

		return(0);
	}

	if (high > fil_space_get_size(space)) {
		/* The area is not whole, return */

		return(0);
	}

	/* If we got this far, read-ahead can be sensible: do it */

	ibuf_mode = inside_ibuf
		? BUF_READ_IBUF_PAGES_ONLY | OS_AIO_SIMULATED_WAKE_LATER
		: BUF_READ_ANY_PAGE | OS_AIO_SIMULATED_WAKE_LATER;

	count = 0;

	/* Since Windows XP seems to schedule the i/o handler thread
	very eagerly, and consequently it does not wait for the
	full read batch to be posted, we use special heuristics here */

	os_aio_simulated_put_read_threads_to_sleep();

	for (i = low; i < high; i++) {
		/* It is only sensible to do read-ahead in the non-sync
		aio mode: hence FALSE as the first parameter */

		if (!ibuf_bitmap_page(zip_size, i)) {
			count += buf_read_page_low(
				&err, FALSE,
				ibuf_mode,
				space, zip_size, FALSE, tablespace_version, i, trx);
			if (err == DB_TABLESPACE_DELETED) {
				ut_print_timestamp(stderr);
				fprintf(stderr,
					"  InnoDB: Warning: in"
					" linear readahead trying to access\n"
					"InnoDB: tablespace %lu page %lu,\n"
					"InnoDB: but the tablespace does not"
					" exist or is just being dropped.\n",
					(ulong) space, (ulong) i);
			}
		}
	}

	/* In simulated aio we wake the aio handler threads only after
	queuing all aio requests, in native aio the following call does
	nothing: */

	os_aio_simulated_wake_handler_threads();

	/* Flush pages from the end of the LRU list if necessary */
	buf_flush_free_margin(buf_pool, TRUE);

#ifdef UNIV_DEBUG
	if (buf_debug_prints && (count > 0)) {
		fprintf(stderr,
			"LINEAR read-ahead space %lu offset %lu pages %lu\n",
			(ulong) space, (ulong) offset, (ulong) count);
	}
#endif /* UNIV_DEBUG */

	/* Read ahead is considered one I/O operation for the purpose of
	LRU policy decision. */
	buf_LRU_stat_inc_io();

	buf_pool->stat.n_ra_pages_read += count;
	return(count);
}
Example #6
0
/*****************************************************************//**
Constructs the last committed version of a clustered index record,
which should be seen by a semi-consistent read.
@return	DB_SUCCESS or DB_MISSING_HISTORY */
UNIV_INTERN
ulint
row_vers_build_for_semi_consistent_read(
/*====================================*/
	const rec_t*	rec,	/*!< in: record in a clustered index; the
				caller must have a latch on the page; this
				latch locks the top of the stack of versions
				of this records */
	mtr_t*		mtr,	/*!< in: mtr holding the latch on rec */
	dict_index_t*	index,	/*!< in: the clustered index */
	ulint**		offsets,/*!< in/out: offsets returned by
				rec_get_offsets(rec, index) */
	mem_heap_t**	offset_heap,/*!< in/out: memory heap from which
				the offsets are allocated */
	mem_heap_t*	in_heap,/*!< in: memory heap from which the memory for
				*old_vers is allocated; memory for possible
				intermediate versions is allocated and freed
				locally within the function */
	const rec_t**	old_vers)/*!< out: rec, old version, or NULL if the
				record does not exist in the view, that is,
				it was freshly inserted afterwards */
{
	const rec_t*	version;
	mem_heap_t*	heap		= NULL;
	byte*		buf;
	ulint		err;
	trx_id_t	rec_trx_id	= ut_dulint_zero;

	ut_ad(dict_index_is_clust(index));
	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX)
	      || mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_S_FIX));
#ifdef UNIV_SYNC_DEBUG
	ut_ad(!rw_lock_own(&(purge_sys->latch), RW_LOCK_SHARED));
#endif /* UNIV_SYNC_DEBUG */

	ut_ad(rec_offs_validate(rec, index, *offsets));

	rw_lock_s_lock(&(purge_sys->latch));
	/* The S-latch on purge_sys prevents the purge view from
	changing.  Thus, if we have an uncommitted transaction at
	this point, then purge cannot remove its undo log even if
	the transaction could commit now. */

	version = rec;

	for (;;) {
		trx_t*		version_trx;
		mem_heap_t*	heap2;
		rec_t*		prev_version;
		trx_id_t	version_trx_id;

		version_trx_id = row_get_rec_trx_id(version, index, *offsets);
		if (rec == version) {
			rec_trx_id = version_trx_id;
		}

		mutex_enter(&kernel_mutex);
		version_trx = trx_get_on_id(version_trx_id);
		if (version_trx
		    && (version_trx->conc_state == TRX_COMMITTED_IN_MEMORY
			|| version_trx->conc_state == TRX_NOT_STARTED)) {

			version_trx = NULL;
		}
		mutex_exit(&kernel_mutex);

		if (!version_trx) {

			/* We found a version that belongs to a
			committed transaction: return it. */

#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
			ut_a(!rec_offs_any_null_extern(version, *offsets));
#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */

			if (rec == version) {
				*old_vers = rec;
				err = DB_SUCCESS;
				break;
			}

			/* We assume that a rolled-back transaction stays in
			TRX_ACTIVE state until all the changes have been
			rolled back and the transaction is removed from
			the global list of transactions. */

			if (!ut_dulint_cmp(rec_trx_id, version_trx_id)) {
				/* The transaction was committed while
				we searched for earlier versions.
				Return the current version as a
				semi-consistent read. */

				version = rec;
				*offsets = rec_get_offsets(version,
							   index, *offsets,
							   ULINT_UNDEFINED,
							   offset_heap);
			}

			buf = mem_heap_alloc(in_heap, rec_offs_size(*offsets));
			*old_vers = rec_copy(buf, version, *offsets);
			rec_offs_make_valid(*old_vers, index, *offsets);
			err = DB_SUCCESS;

			break;
		}

		heap2 = heap;
		heap = mem_heap_create(1024);

		err = trx_undo_prev_version_build(rec, mtr, version, index,
						  *offsets, heap,
						  &prev_version);
		if (heap2) {
			mem_heap_free(heap2); /* free version */
		}

		if (UNIV_UNLIKELY(err != DB_SUCCESS)) {
			break;
		}

		if (prev_version == NULL) {
			/* It was a freshly inserted version */
			*old_vers = NULL;
			err = DB_SUCCESS;

			break;
		}

		version = prev_version;
		*offsets = rec_get_offsets(version, index, *offsets,
					   ULINT_UNDEFINED, offset_heap);
#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
		ut_a(!rec_offs_any_null_extern(version, *offsets));
#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
	}/* for (;;) */

	if (heap) {
		mem_heap_free(heap);
	}
	rw_lock_s_unlock(&(purge_sys->latch));

	return(err);
}
Example #7
0
/*****************************************************************//**
Constructs the version of a clustered index record which a consistent
read should see. We assume that the trx id stored in rec is such that
the consistent read should not see rec in its present version.
@return	DB_SUCCESS or DB_MISSING_HISTORY */
UNIV_INTERN
ulint
row_vers_build_for_consistent_read(
/*===============================*/
	const rec_t*	rec,	/*!< in: record in a clustered index; the
				caller must have a latch on the page; this
				latch locks the top of the stack of versions
				of this records */
	mtr_t*		mtr,	/*!< in: mtr holding the latch on rec */
	dict_index_t*	index,	/*!< in: the clustered index */
	ulint**		offsets,/*!< in/out: offsets returned by
				rec_get_offsets(rec, index) */
	read_view_t*	view,	/*!< in: the consistent read view */
	mem_heap_t**	offset_heap,/*!< in/out: memory heap from which
				the offsets are allocated */
	mem_heap_t*	in_heap,/*!< in: memory heap from which the memory for
				*old_vers is allocated; memory for possible
				intermediate versions is allocated and freed
				locally within the function */
	rec_t**		old_vers)/*!< out, own: old version, or NULL if the
				record does not exist in the view, that is,
				it was freshly inserted afterwards */
{
	const rec_t*	version;
	rec_t*		prev_version;
	trx_id_t	trx_id;
	mem_heap_t*	heap		= NULL;
	byte*		buf;
	ulint		err;

	ut_ad(dict_index_is_clust(index));
	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX)
	      || mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_S_FIX));
#ifdef UNIV_SYNC_DEBUG
	ut_ad(!rw_lock_own(&(purge_sys->latch), RW_LOCK_SHARED));
#endif /* UNIV_SYNC_DEBUG */

	ut_ad(rec_offs_validate(rec, index, *offsets));

	trx_id = row_get_rec_trx_id(rec, index, *offsets);

	ut_ad(!read_view_sees_trx_id(view, trx_id));

	rw_lock_s_lock(&(purge_sys->latch));
	version = rec;

	for (;;) {
		mem_heap_t*	heap2	= heap;
		trx_undo_rec_t* undo_rec;
		roll_ptr_t	roll_ptr;
		undo_no_t	undo_no;
		heap = mem_heap_create(1024);

		/* If we have high-granularity consistent read view and
		creating transaction of the view is the same as trx_id in
		the record we see this record only in the case when
		undo_no of the record is < undo_no in the view. */

		if (view->type == VIEW_HIGH_GRANULARITY
		    && ut_dulint_cmp(view->creator_trx_id, trx_id) == 0) {

			roll_ptr = row_get_rec_roll_ptr(version, index,
							*offsets);
			undo_rec = trx_undo_get_undo_rec_low(roll_ptr, heap);
			undo_no = trx_undo_rec_get_undo_no(undo_rec);
			mem_heap_empty(heap);

			if (ut_dulint_cmp(view->undo_no, undo_no) > 0) {
				/* The view already sees this version: we can
				copy it to in_heap and return */

#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
				ut_a(!rec_offs_any_null_extern(
					     version, *offsets));
#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */

				buf = mem_heap_alloc(in_heap,
						     rec_offs_size(*offsets));
				*old_vers = rec_copy(buf, version, *offsets);
				rec_offs_make_valid(*old_vers, index,
						    *offsets);
				err = DB_SUCCESS;

				break;
			}
		}

		err = trx_undo_prev_version_build(rec, mtr, version, index,
						  *offsets, heap,
						  &prev_version);
		if (heap2) {
			mem_heap_free(heap2); /* free version */
		}

		if (err != DB_SUCCESS) {
			break;
		}

		if (prev_version == NULL) {
			/* It was a freshly inserted version */
			*old_vers = NULL;
			err = DB_SUCCESS;

			break;
		}

		*offsets = rec_get_offsets(prev_version, index, *offsets,
					   ULINT_UNDEFINED, offset_heap);

#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
		ut_a(!rec_offs_any_null_extern(prev_version, *offsets));
#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */

		trx_id = row_get_rec_trx_id(prev_version, index, *offsets);

		if (read_view_sees_trx_id(view, trx_id)) {

			/* The view already sees this version: we can copy
			it to in_heap and return */

			buf = mem_heap_alloc(in_heap, rec_offs_size(*offsets));
			*old_vers = rec_copy(buf, prev_version, *offsets);
			rec_offs_make_valid(*old_vers, index, *offsets);
			err = DB_SUCCESS;

			break;
		}

		version = prev_version;
	}/* for (;;) */

	mem_heap_free(heap);
	rw_lock_s_unlock(&(purge_sys->latch));

	return(err);
}
Example #8
0
/*************************************************************************
Checks if index currently is mentioned as a referenced index in a foreign
key constraint. This function also loads into the dictionary cache the
possible referencing table. */
static
ibool
row_upd_index_is_referenced(
/*========================*/
				/* out: TRUE if referenced; NOTE that since
				we do not hold dict_foreign_key_check_lock
				when leaving the function, it may be that
				the referencing table has been dropped when
				we leave this function: this function is only
				for heuristic use! */
	dict_index_t*	index)	/* in: index */
{
	dict_table_t*	table	= index->table;
	dict_foreign_t*	foreign;
	ulint		phase	= 1;

try_again:	
	if (!UT_LIST_GET_FIRST(table->referenced_list)) {

		return(FALSE);
	}

	if (phase == 2) {
		mutex_enter(&(dict_sys->mutex));
	}

	rw_lock_s_lock(&dict_foreign_key_check_lock);

	foreign = UT_LIST_GET_FIRST(table->referenced_list);

	while (foreign) {
		if (foreign->referenced_index == index) {
			if (foreign->foreign_table == NULL) {
				if (phase == 2) {
					dict_table_get_low(foreign->
							foreign_table_name);
				} else {
					phase = 2;
					rw_lock_s_unlock(
						&dict_foreign_key_check_lock);
					goto try_again;
				}
			}

			rw_lock_s_unlock(&dict_foreign_key_check_lock);

			if (phase == 2) {
				mutex_exit(&(dict_sys->mutex));
			}

			return(TRUE);
		}

		foreign = UT_LIST_GET_NEXT(referenced_list, foreign);
	}
	
	rw_lock_s_unlock(&dict_foreign_key_check_lock);

	if (phase == 2) {
		mutex_exit(&(dict_sys->mutex));
	}

	return(FALSE);
}