slab.h

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/*
 * 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 <adt/list.h>
#include <synch/spinlock.h>
#include <atomic.h>
#include <mm/frame.h>

#define SLAB_MIN_MALLOC_W 4

#define SLAB_MAX_MALLOC_W 18

#define SLAB_MAG_SIZE  4

#define SLAB_INSIDE_SIZE   (PAGE_SIZE >> 3)

#define SLAB_MAX_BADNESS(cache)   ((PAGE_SIZE << (cache)->order) >> 2)

/* slab_reclaim constants */
#define SLAB_RECLAIM_ALL  0x1 
/* cache_create flags */
#define SLAB_CACHE_NOMAGAZINE 0x1 
#define SLAB_CACHE_SLINSIDE   0x2 
#define SLAB_CACHE_MAGDEFERRED (0x4 | SLAB_CACHE_NOMAGAZINE)

typedef struct {
        link_t link;
        count_t busy;  
        count_t size;  
        void *objs[0]; 
}slab_magazine_t;

typedef struct {
        slab_magazine_t *current;
        slab_magazine_t *last;
        SPINLOCK_DECLARE(lock);
}slab_mag_cache_t;


typedef struct {
        char *name;

        link_t link;
        /* Configuration */
        size_t size;      
        int (*constructor)(void *obj, int kmflag);
        int (*destructor)(void *obj);
        int flags;        
        /* Computed values */
        __u8 order;        
        int objects;      
        /* Statistics */
        atomic_t allocated_slabs;
        atomic_t allocated_objs;
        atomic_t cached_objs;
        atomic_t magazine_counter; 
        /* Slabs */
        link_t full_slabs;     
        link_t partial_slabs;  
        SPINLOCK_DECLARE(slablock);
        /* Magazines  */
        link_t magazines;      
        SPINLOCK_DECLARE(maglock);

        slab_mag_cache_t *mag_cache;
}slab_cache_t;

extern slab_cache_t * slab_cache_create(char *name,
                                        size_t size,
                                        size_t align,
                                        int (*constructor)(void *obj, int kmflag),
                                        int (*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);

extern void slab_cache_init(void);
extern void slab_enable_cpucache(void);

/* kconsole debug */
extern void slab_print_list(void);

/* malloc support */
extern void * malloc(unsigned int size, int flags);
extern void free(void *obj);
#endif

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