/**************************************************************
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 *
 *************************************************************/


#ifndef INCLUDED_RTL_ALLOC_CACHE_H
#define INCLUDED_RTL_ALLOC_CACHE_H

#include "sal/types.h"
#include "rtl/alloc.h"
#include "alloc_impl.h"

#ifdef __cplusplus
extern "C" {
#endif

/** rtl_cache_stat_type
 *  @internal
 */
typedef struct rtl_cache_stat_st rtl_cache_stat_type;
struct rtl_cache_stat_st
{
	sal_uInt64 m_alloc;
	sal_uInt64 m_free;

	sal_Size   m_mem_total;
	sal_Size   m_mem_alloc;
};


/** rtl_cache_bufctl_type
 *  @internal
 */
typedef struct rtl_cache_bufctl_st rtl_cache_bufctl_type;
struct rtl_cache_bufctl_st
{
	rtl_cache_bufctl_type * m_next; /* linkage */

	sal_uIntPtr             m_addr; /* buffer address  */
	sal_uIntPtr             m_slab; /* parent slab address */
};


/** rtl_cache_slab_type
 *  @internal
 */
typedef struct rtl_cache_slab_st rtl_cache_slab_type;
struct rtl_cache_slab_st
{
	rtl_cache_slab_type *   m_slab_next; /* slab linkage */
	rtl_cache_slab_type *   m_slab_prev; /* slab linkage */

	sal_Size                m_ntypes;    /* number of buffers used */
	sal_uIntPtr             m_data;      /* buffer start addr */

	sal_uIntPtr             m_bp;        /* free buffer linkage 'base pointer'  */
	rtl_cache_bufctl_type * m_sp;        /* free buffer linkage 'stack pointer' */
};


/** rtl_cache_magazine_type
 *  @internal
 */
#define RTL_CACHE_MAGAZINE_SIZE 61

typedef struct rtl_cache_magazine_st rtl_cache_magazine_type;
struct rtl_cache_magazine_st
{
	rtl_cache_magazine_type * m_mag_next; /* depot linkage */

	sal_Size                  m_mag_size;
	sal_Size                  m_mag_used;

	void *                    m_objects[RTL_CACHE_MAGAZINE_SIZE];
};


/** rtl_cache_depot_type
 *  @internal
 */
typedef struct rtl_cache_depot_st rtl_cache_depot_type;
struct rtl_cache_depot_st
{
	/* magazine list */
	rtl_cache_magazine_type * m_mag_next;  /* linkage */
	sal_Size                  m_mag_count; /* count */

	/* working set parameters */
	sal_Size                  m_curr_min;
	sal_Size                  m_prev_min;
};


/** rtl_cache_type
 *  @internal
 */
#define RTL_CACHE_HASH_SIZE        8

#define RTL_CACHE_FEATURE_HASH        1
#define RTL_CACHE_FEATURE_BULKDESTROY 2
#define RTL_CACHE_FEATURE_RESCALE     4 /* within hash rescale operation */

struct rtl_cache_st
{
	/* linkage */
	rtl_cache_type *          m_cache_next;
	rtl_cache_type *          m_cache_prev;

	/* properties */
	char                      m_name[RTL_CACHE_NAME_LENGTH + 1];
	long                      m_features;

	sal_Size                  m_type_size;   /* const */
	sal_Size                  m_type_align;  /* const */
	sal_Size                  m_type_shift;  /* log2(m_type_size); const */

	int  (SAL_CALL * m_constructor)(void * obj, void * userarg); /* const */
	void (SAL_CALL * m_destructor) (void * obj, void * userarg); /* const */
	void (SAL_CALL * m_reclaim)    (void * userarg);             /* const */
	void *                    m_userarg;

	/* slab layer */
	rtl_memory_lock_type      m_slab_lock;
	rtl_cache_stat_type       m_slab_stats;

	rtl_arena_type *          m_source;     /* slab supplier; const */
	sal_Size                  m_slab_size;  /* const */
	sal_Size                  m_ntypes;     /* number of buffers per slab; const */
	sal_Size                  m_ncolor;     /* next slab color */
	sal_Size                  m_ncolor_max; /* max. slab color */

	rtl_cache_slab_type       m_free_head;
	rtl_cache_slab_type       m_used_head;

	rtl_cache_bufctl_type **  m_hash_table;
	rtl_cache_bufctl_type *   m_hash_table_0[RTL_CACHE_HASH_SIZE];
	sal_Size                  m_hash_size;  /* m_hash_mask + 1   */
	sal_Size                  m_hash_shift; /* log2(m_hash_size) */

	/* depot layer */
	rtl_memory_lock_type      m_depot_lock;

	rtl_cache_depot_type      m_depot_empty;
	rtl_cache_depot_type      m_depot_full;

	rtl_cache_type *          m_magazine_cache; /* magazine supplier; const */

	/* cpu layer */
	rtl_cache_magazine_type * m_cpu_curr;
	rtl_cache_magazine_type * m_cpu_prev;

	rtl_cache_stat_type       m_cpu_stats;
};


#ifdef __cplusplus
}
#endif

#endif /* INCLUDED_RTL_ALLOC_CACHE_H */