mariadb/include/buf0buddy.ic
marko 8e3e3d16d3 branches/zip: Implement the whole allocation algorithm of compressed pages.
buf_LRU_free_block(): Free compressed-only pages and their
descriptors with buf_buddy_free().

buf_LRU_get_free_only(): New function for returning a block from
buf_pool->free if one is available.  Split from buf_LRU_get_free_block().

buf_buddy_alloc_zip(): Rename from buf_buddy_alloc_low() and make static.
Remove parameter "split".  Always try to split.

buf_buddy_free_block(): Rename to buf_buddy_block_free().

buf_buddy_block_register(): New function for registering buf_block_t
objects reserved by the allocator.

buf_buddy_alloc_from(): New function for allocating an object from a
bigger object, and putting the unused parts on the free list.

buf_buddy_alloc_clean_zip(): New function for allocating memory by
replacing an unmodified compressed page.

buf_buddy_alloc_low(): New function for allocating memory, either from
the free lists of compressed pages, from the global free list, or from
unmodified pages in the buffer pool.
2006-12-11 14:27:43 +00:00

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/******************************************************
Binary buddy allocator for compressed pages
(c) 2006 Innobase Oy
Created December 2006 by Marko Makela
*******************************************************/
#ifdef UNIV_MATERIALIZE
# undef UNIV_INLINE
# define UNIV_INLINE
#endif
#include "buf0buddy.h"
#include "ut0ut.h"
/**************************************************************************
Allocate a block. */
void*
buf_buddy_alloc_low(
/*================*/
/* out: pointer to the start of the block */
ulint i) /* in: index of buf_pool->zip_free[] */
__attribute__((malloc));
/**************************************************************************
Deallocate a block. */
void
buf_buddy_free_low(
/*===============*/
void* buf, /* in: block to free */
ulint i) /* in: index of buf_pool->zip_free[] */
__attribute__((nonnull));
/**************************************************************************
Get the offset of the buddy of a compressed page frame. */
UNIV_INLINE
lint
buf_buddy_get_offset(
/*=================*/
/* out: offset of the buddy relative to page */
const void* page, /* in: compressed page */
ulint size) /* in: page size in bytes */
{
ut_ad(ut_is_2pow(size));
ut_ad(size >= BUF_BUDDY_LOW);
ut_ad(size < BUF_BUDDY_HIGH);
if (((ulint) page) & size) {
return(-(lint) size);
} else {
return((lint) size);
}
}
/**************************************************************************
Get the index of buf_pool->zip_free[] for a given block size. */
UNIV_INLINE
ulint
buf_buddy_get_slot(
/*===============*/
/* out: index of buf_pool->zip_free[] */
ulint size) /* in: block size */
{
ulint i;
ulint s;
for (i = 0, s = BUF_BUDDY_LOW; s < size; i++, s <<= 1);
ut_ad(i < BUF_BUDDY_SIZES);
return(i);
}
/**************************************************************************
Allocate a block. */
UNIV_INLINE
void*
buf_buddy_alloc(
/*============*/
/* out: pointer to the start of the block */
ulint size) /* in: block size, up to UNIV_PAGE_SIZE / 2 */
{
#ifdef UNIV_SYNC_DEBUG
ut_a(mutex_own(&buf_pool->mutex));
#endif /* UNIV_SYNC_DEBUG */
return(buf_buddy_alloc_low(buf_buddy_get_slot(size)));
}
/**************************************************************************
Deallocate a block. */
UNIV_INLINE
void
buf_buddy_free(
/*===========*/
void* buf, /* in: block to free */
ulint size) /* in: block size, up to UNIV_PAGE_SIZE / 2 */
{
#ifdef UNIV_SYNC_DEBUG
ut_a(mutex_own(&buf_pool->mutex));
#endif /* UNIV_SYNC_DEBUG */
buf_buddy_free_low(buf, buf_buddy_get_slot(size));
}
#ifdef UNIV_MATERIALIZE
# undef UNIV_INLINE
# define UNIV_INLINE UNIV_INLINE_ORIGINAL
#endif