buf0buddy.h

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/** @file include/buf0buddy.h
 Binary buddy allocator for compressed pages
 
 Created December 2006 by Marko Makela
 *******************************************************/
 
#ifndef buf0buddy_h
#define buf0buddy_h
 
#include "buf0types.h"
#include "univ.i"
 
/** Allocate a block. This function should only be used for allocating
compressed page frames. The thread calling this function must hold
buf_pool->LRU_list_mutex and must not hold buf_pool->zip_mutex or any
block->mutex.
@param[in,out]  buf_pool        buffer pool in which the page resides
@param[in]      size            compressed page size, between
                                UNIV_ZIP_SIZE_MIN and UNIV_PAGE_SIZE
@return allocated block, never NULL */
static inline byte *buf_buddy_alloc(buf_pool_t *buf_pool, ulint size)
    MY_ATTRIBUTE((malloc));
 
/** Deallocate a block.
@param[in,out]  buf_pool        buffer pool in which the block resides
@param[in]      buf             block to be freed, must not be pointed to
                                by the buffer pool
@param[in]      size            block size, up to UNIV_PAGE_SIZE */
static inline void buf_buddy_free(buf_pool_t *buf_pool, void *buf, ulint size);
 
/** Try to reallocate a block.
@param[in]      buf_pool        buffer pool instance
@param[in]      buf             block to be reallocated, must be pointed
to by the buffer pool
@param[in]      size            block size, up to UNIV_PAGE_SIZE
@retval true    if succeeded or if failed because the block was fixed
@retval false   if failed because of no free blocks. */
bool buf_buddy_realloc(buf_pool_t *buf_pool, void *buf, ulint size);
 
/** Combine all pairs of free buddies.
@param[in]      buf_pool        buffer pool instance */
void buf_buddy_condense_free(buf_pool_t *buf_pool);
 
#include "buf0buddy.ic"
 
#endif /* buf0buddy_h */