Merge XtraDB from Percona-Server-5.5.20-24.1 into MariaDB 5.5.

1 files changed, 39 insertions, 29 deletions

diff --git a/storage/xtradb/include/buf0buf.h b/storage/xtradb/include/buf0buf.h
index d85dac5cc91..0ea74fb9eb2 100644
--- a/storage/xtradb/include/buf0buf.h
+++ b/storage/xtradb/include/buf0buf.h
@@ -244,13 +244,11 @@ buf_pool_free(
 	ulint	n_instances);	/*!< in: numbere of instances to free */
 
 /********************************************************************//**
-Drops the adaptive hash index.  To prevent a livelock, this function
-is only to be called while holding btr_search_latch and while
-btr_search_enabled == FALSE. */
+Clears the adaptive hash index on all pages in the buffer pool. */
 UNIV_INTERN
 void
-buf_pool_drop_hash_index(void);
-/*==========================*/
+buf_pool_clear_hash_index(void);
+/*===========================*/
 
 /********************************************************************//**
 Relocate a buffer control block.  Relocates the block on the LRU list
@@ -583,17 +581,6 @@ buf_page_peek_if_too_old(
 /*=====================*/
 	const buf_page_t*	bpage);	/*!< in: block to make younger */
 /********************************************************************//**
-Returns the current state of is_hashed of a page. FALSE if the page is
-not in the pool. NOTE that this operation does not fix the page in the
-pool if it is found there.
-@return	TRUE if page hash index is built in search system */
-UNIV_INTERN
-ibool
-buf_page_peek_if_search_hashed(
-/*===========================*/
-	ulint	space,	/*!< in: space id */
-	ulint	offset);/*!< in: page number */
-/********************************************************************//**
 Gets the youngest modification log sequence number for a frame.
 Returns zero if not file page or no modification occurred yet.
 @return	newest modification to page */
@@ -952,7 +939,27 @@ buf_block_set_io_fix(
 /*=================*/
 	buf_block_t*	block,	/*!< in/out: control block */
 	enum buf_io_fix	io_fix);/*!< in: io_fix state */
-
+/*********************************************************************//**
+Makes a block sticky. A sticky block implies that even after we release
+the buf_pool->mutex and the block->mutex:
+* it cannot be removed from the flush_list
+* the block descriptor cannot be relocated
+* it cannot be removed from the LRU list
+Note that:
+* the block can still change its position in the LRU list
+* the next and previous pointers can change. */
+UNIV_INLINE
+void
+buf_page_set_sticky(
+/*================*/
+	buf_page_t*	bpage);	/*!< in/out: control block */
+/*********************************************************************//**
+Removes stickiness of a block. */
+UNIV_INLINE
+void
+buf_page_unset_sticky(
+/*==================*/
+	buf_page_t*	bpage);	/*!< in/out: control block */
 /********************************************************************//**
 Determine if a buffer block can be relocated in memory.  The block
 can be dirty, but it must not be I/O-fixed or bufferfixed. */
@@ -1569,13 +1576,16 @@ struct buf_block_struct{
 	/* @} */
 
 	/** @name Hash search fields
-	These 6 fields may only be modified when we have
+	These 5 fields may only be modified when we have
 	an x-latch on btr_search_latch AND
 	- we are holding an s-latch or x-latch on buf_block_struct::lock or
 	- we know that buf_block_struct::buf_fix_count == 0.
 
 	An exception to this is when we init or create a page
-	in the buffer pool in buf0buf.c. */
+	in the buffer pool in buf0buf.c.
+
+	Another exception is that assigning block->index = NULL
+	is allowed whenever holding an x-latch on btr_search_latch. */
 
 	/* @{ */
 
@@ -1584,21 +1594,21 @@ struct buf_block_struct{
 					pointers in the adaptive hash index
 					pointing to this frame */
 #endif /* UNIV_AHI_DEBUG || UNIV_DEBUG */
-	volatile unsigned	is_hashed:1;	/*!< TRUE if hash index has
-					already been built on this
-					page; note that it does not
-					guarantee that the index is
-					complete, though: there may
-					have been hash collisions,
-					record deletions, etc. */
 	unsigned	curr_n_fields:10;/*!< prefix length for hash indexing:
 					number of full fields */
 	unsigned	curr_n_bytes:15;/*!< number of bytes in hash
 					indexing */
 	unsigned	curr_left_side:1;/*!< TRUE or FALSE in hash indexing */
-	dict_index_t*	index;		/*!< Index for which the adaptive
-					hash index has been created. */
-	volatile rw_lock_t*	btr_search_latch;
+	dict_index_t*	index;		/*!< Index for which the
+					adaptive hash index has been
+					created, or NULL if the page
+					does not exist in the
+					index. Note that it does not
+					guarantee that the index is
+					complete, though: there may
+					have been hash collisions,
+					record deletions, etc. */
+	volatile rw_lock_t*     btr_search_latch;
 	/* @} */
 # ifdef UNIV_SYNC_DEBUG
 	/** @name Debug fields */