gm_lookaside.c File Reference

#include "gm_call_trace.h"
#include "gm_debug.h"
#include "gm_internal.h"
#include "gm_malloc_debug.h"
#include "gm_struct_lock.h"

Functions
GM_ENTRY_POINT void *	gm_lookaside_alloc (struct gm_lookaside *l)
GM_ENTRY_POINT void *	gm_lookaside_zalloc (struct gm_lookaside *l)
GM_ENTRY_POINT void	gm_lookaside_free (void *ptr)
GM_ENTRY_POINT struct gm_lookaside *	gm_create_lookaside (gm_size_t entry_len, gm_size_t min_entry_cnt)
GM_ENTRY_POINT void	gm_destroy_lookaside (struct gm_lookaside *l)

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Detailed Description

This file contains the GM API functions gm_create_lookaside(), gm_destroy_lookaside(), gm_lookaside_alloc(), gm_lookaside_zalloc(), and gm_lookaside_free().

This file implements a lookaside list. It is mainly intended to allow efficient memory allocation of small structures in kernels where the minimum memory allocation is a page, but is not kernel-specific.

GM implements a lookaside list, which may be used to manage small fixed-length blocks more efficiently than gm_malloc() and gm_free(). Lookaside lists can also be used to ensure that at least a minimum number of blocks are available for allocation at all times.

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Function Documentation

GM_ENTRY_POINT void* gm_lookaside_alloc (  struct gm_lookaside *  l  )

gm_lookaside_alloc() allocates an entry from the lookaside table, with debugging. It returns a buffer of size ENTRY_LEN specified when the entry list L was created, or `0' if the buffer could not be allocated. Return values: ptr  Buffer of size ENTRY_LEN. Parameters: l  (IN) Handle to the gm_lookaside list. Author: Glenn Brown Version: GM_API_VERSION (as defined in gm.h)

GM_ENTRY_POINT void* gm_lookaside_zalloc (  struct gm_lookaside *  l  )

gm_lookaside_zalloc() allocates and clear an entry from the lookaside table. Return values: ptr  Parameters: l  (IN) Handle to the gm_lookaside list. Author: Glenn Brown Version: GM_API_VERSION (as defined in gm.h)

GM_ENTRY_POINT void gm_lookaside_free (  void *  ptr  )

gm_lookaside_free() schedules an allocated entry to be freed, and actually performs any scheduled free. It frees a block of memory previously allocated by a call to gm_lookaside_alloc(). The contents of the block of memory are guaranteed to be unchanged until the next operation is performed on the lookaside list. Parameters: ptr  (IN) Pointer to the entry to be freed. Author: Glenn Brown Version: GM_API_VERSION (as defined in gm.h)

GM_ENTRY_POINT struct gm_lookaside* gm_create_lookaside (  gm_size_t  entry_len, gm_size_t  min_entry_cnt )

gm_create_lookaside() returns a newly created lookaside list to be used to allocate blocks of ENTRY_LEN bytes. MIN_ENTRY_CNT entries are preallocated. Return values: gm_lookaside  Handle to the lookaside table. Parameters: entry_len  (IN) min_entry_cnt  (IN) Author: Glenn Brown Version: GM_API_VERSION (as defined in gm.h)

GM_ENTRY_POINT void gm_destroy_lookaside (  struct gm_lookaside *  l  )

gm_destroy_lookaside() frees a lookaside list and all associated resources, including any buffers currently allocated from the lookaside list. Parameters: l  (IN) Handle to the lookaside table. Author: Glenn Brown Version: GM_API_VERSION (as defined in gm.h)

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