4 * Chunk based memory management for Lock-Free RCU Hash Table
6 * Copyright 2011 - Lai Jiangshan <laijs@cn.fujitsu.com>
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 #include "rculfhash-internal.h"
29 void cds_lfht_alloc_bucket_table(struct cds_lfht
*ht
, unsigned long order
)
32 ht
->tbl_chunk
[0] = calloc(ht
->min_nr_alloc_buckets
,
33 sizeof(struct cds_lfht_node
));
34 assert(ht
->tbl_chunk
[0]);
35 } else if (order
> ht
->min_alloc_buckets_order
) {
36 unsigned long i
, len
= 1UL << (order
- 1 - ht
->min_alloc_buckets_order
);
38 for (i
= len
; i
< 2 * len
; i
++) {
39 ht
->tbl_chunk
[i
] = calloc(ht
->min_nr_alloc_buckets
,
40 sizeof(struct cds_lfht_node
));
41 assert(ht
->tbl_chunk
[i
]);
44 /* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
48 * cds_lfht_free_bucket_table() should be called with decreasing order.
49 * When cds_lfht_free_bucket_table(0) is called, it means the whole
53 void cds_lfht_free_bucket_table(struct cds_lfht
*ht
, unsigned long order
)
56 poison_free(ht
->tbl_chunk
[0]);
57 else if (order
> ht
->min_alloc_buckets_order
) {
58 unsigned long i
, len
= 1UL << (order
- 1 - ht
->min_alloc_buckets_order
);
60 for (i
= len
; i
< 2 * len
; i
++)
61 poison_free(ht
->tbl_chunk
[i
]);
63 /* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
67 struct cds_lfht_node
*bucket_at(struct cds_lfht
*ht
, unsigned long index
)
69 unsigned long chunk
, offset
;
71 chunk
= index
>> ht
->min_alloc_buckets_order
;
72 offset
= index
& (ht
->min_nr_alloc_buckets
- 1);
73 return &ht
->tbl_chunk
[chunk
][offset
];
77 struct cds_lfht
*alloc_cds_lfht(unsigned long min_nr_alloc_buckets
,
78 unsigned long max_nr_buckets
)
80 unsigned long nr_chunks
, cds_lfht_size
;
82 min_nr_alloc_buckets
= max(min_nr_alloc_buckets
,
83 max_nr_buckets
/ MAX_CHUNK_TABLE
);
84 nr_chunks
= max_nr_buckets
/ min_nr_alloc_buckets
;
85 cds_lfht_size
= offsetof(struct cds_lfht
, tbl_chunk
) +
86 sizeof(struct cds_lfht_node
*) * nr_chunks
;
87 cds_lfht_size
= max(cds_lfht_size
, sizeof(struct cds_lfht
));
89 return __default_alloc_cds_lfht(
90 &cds_lfht_mm_chunk
, cds_lfht_size
,
91 min_nr_alloc_buckets
, max_nr_buckets
);
94 const struct cds_lfht_mm_type cds_lfht_mm_chunk
= {
95 .alloc_cds_lfht
= alloc_cds_lfht
,
96 .alloc_bucket_table
= cds_lfht_alloc_bucket_table
,
97 .free_bucket_table
= cds_lfht_free_bucket_table
,
98 .bucket_at
= bucket_at
,