/*
* Copyright (C) 2006 Ondrej Palkovsky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __SLAB_H__
#define __SLAB_H__
#include <list.h>
#include <synch/spinlock.h>
#include <arch/atomic.h>
/** Initial Magazine size (TODO: dynamically growing magazines) */
#define SLAB_MAG_SIZE 4
/** If object size is less, store control structure inside SLAB */
#define SLAB_INSIDE_SIZE (PAGE_SIZE / 6)
/** Maximum wasted space we allow for cache */
#define SLAB_MAX_BADNESS(cache) ((PAGE_SIZE << (cache)->order) / 4)
/* slab_reclaim constants */
#define SLAB_RECLAIM_ALL 0x1 /**< Reclaim all possible memory, because
* we are in memory stress */
/* cache_create flags */
#define SLAB_CACHE_NOMAGAZINE 0x1 /**< Do not use per-cpu cache */
#define SLAB_CACHE_SLINSIDE 0x2 /**< Have control structure inside SLAB */
typedef struct {
link_t link;
count_t busy; /**< Count of full slots in magazine */
count_t size; /**< Number of slots in magazine */
void *objs[0]; /**< Slots in magazine */
}slab_magazine_t;
typedef struct {
char *name;
SPINLOCK_DECLARE(lock);
link_t link;
/* Configuration */
size_t size; /**< Size of SLAB position - align_up(sizeof(obj)) */
int (*constructor)(void *obj, int kmflag);
void (*destructor)(void *obj);
int flags; /**< Flags changing behaviour of cache */
/* Computed values */
__u8 order; /**< Order of frames to be allocated */
int objects; /**< Number of objects that fit in */
/* Statistics */
atomic_t allocated_slabs;
atomic_t allocated_objs;
/* Slabs */
link_t full_slabs; /**< List of full slabs */
link_t partial_slabs; /**< List of partial slabs */
/* Magazines */
link_t magazines; /**< List o full magazines */
/** CPU cache */
struct {
slab_magazine_t *current;
slab_magazine_t *last;
SPINLOCK_DECLARE(lock);
}mag_cache[0];
}slab_cache_t;
extern slab_cache_t * slab_cache_create(char *name,
size_t size,
size_t align,
int (*constructor)(void *obj, int kmflag),
void (*destructor)(void *obj),
int flags);
extern void slab_cache_destroy(slab_cache_t *cache);
extern void * slab_alloc(slab_cache_t *cache, int flags);
extern void slab_free(slab_cache_t *cache, void *obj);
extern count_t slab_reclaim(int flags);
/** Initialize SLAB subsytem */
extern void slab_cache_init(void);
/* KConsole debug */
extern void slab_print_list(void);
#endif