/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 1998-2016. All Rights Reserved.
*
* Licensed 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.
*
* %CopyrightEnd%
*/
#ifndef _DB_HASH_H
#define _DB_HASH_H
#include "erl_db_util.h" /* DbTerm & DbTableCommon */
typedef struct fixed_deletion {
int slot;
struct fixed_deletion *next;
} FixedDeletion;
typedef struct hash_db_term {
struct hash_db_term* next; /* next bucket */
HashValue hvalue; /* stored hash value */
DbTerm dbterm; /* The actual term */
} HashDbTerm;
#ifdef ERTS_DB_HASH_LOCK_CNT
#define DB_HASH_LOCK_CNT ERTS_DB_HASH_LOCK_CNT
#else
#define DB_HASH_LOCK_CNT 64
#endif
typedef struct db_table_hash_fine_locks {
union {
erts_smp_rwmtx_t lck;
byte _cache_line_alignment[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_smp_rwmtx_t))];
}lck_vec[DB_HASH_LOCK_CNT];
} DbTableHashFineLocks;
typedef struct db_table_hash {
DbTableCommon common;
erts_smp_atomic_t segtab; /* The segment table (struct segment**) */
struct segment* first_segtab[1];
erts_smp_atomic_t szm; /* current size mask. */
/* SMP: nslots and nsegs are protected by is_resizing or table write lock */
int nslots; /* Total number of slots */
int nsegs; /* Size of segment table */
/* List of slots where elements have been deleted while table was fixed */
erts_smp_atomic_t fixdel; /* (FixedDeletion*) */
erts_smp_atomic_t nactive; /* Number of "active" slots */
#ifdef ERTS_SMP
erts_smp_atomic_t is_resizing; /* grow/shrink in progress */
DbTableHashFineLocks* locks;
#endif
} DbTableHash;
/*
** Function prototypes, looks the same (except the suffix) for all
** table types. The process is always an [in out] parameter.
*/
void db_initialize_hash(void);
void db_unfix_table_hash(DbTableHash *tb /* [in out] */);
Uint db_kept_items_hash(DbTableHash *tb);
/* Interface for meta pid table */
int db_create_hash(Process *p,
DbTable *tbl /* [in out] */);
int db_put_hash(DbTable *tbl, Eterm obj, int key_clash_fail);
int db_get_hash(Process *p, DbTable *tbl, Eterm key, Eterm *ret);
int db_erase_hash(DbTable *tbl, Eterm key, Eterm *ret);
int db_get_element_array(DbTable *tbl,
Eterm key,
int ndex,
Eterm *ret,
int *num_ret);
int db_erase_bag_exact2(DbTable *tbl, Eterm key, Eterm value);
/* not yet in method table */
int db_mark_all_deleted_hash(DbTable *tbl);
typedef struct {
float avg_chain_len;
float std_dev_chain_len;
float std_dev_expected;
int max_chain_len;
int min_chain_len;
int kept_items;
}DbHashStats;
void db_calc_stats_hash(DbTableHash* tb, DbHashStats*);
Eterm erts_ets_hash_get_memstate(Process*, DbTableHash* tb);
Eterm erts_ets_hash_restore_memstate(DbTableHash* tb, Eterm memstate);
#endif /* _DB_HASH_H */
