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
24 #include "rculfhash-internal.h"
27 void lttng_ust_lfht_alloc_bucket_table(struct lttng_ust_lfht
*ht
, unsigned long order
)
30 ht
->tbl_chunk
[0] = calloc(ht
->min_nr_alloc_buckets
,
31 sizeof(struct lttng_ust_lfht_node
));
32 assert(ht
->tbl_chunk
[0]);
33 } else if (order
> ht
->min_alloc_buckets_order
) {
34 unsigned long i
, len
= 1UL << (order
- 1 - ht
->min_alloc_buckets_order
);
36 for (i
= len
; i
< 2 * len
; i
++) {
37 ht
->tbl_chunk
[i
] = calloc(ht
->min_nr_alloc_buckets
,
38 sizeof(struct lttng_ust_lfht_node
));
39 assert(ht
->tbl_chunk
[i
]);
42 /* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
46 * lttng_ust_lfht_free_bucket_table() should be called with decreasing order.
47 * When lttng_ust_lfht_free_bucket_table(0) is called, it means the whole
51 void lttng_ust_lfht_free_bucket_table(struct lttng_ust_lfht
*ht
, unsigned long order
)
54 poison_free(ht
->tbl_chunk
[0]);
55 else if (order
> ht
->min_alloc_buckets_order
) {
56 unsigned long i
, len
= 1UL << (order
- 1 - ht
->min_alloc_buckets_order
);
58 for (i
= len
; i
< 2 * len
; i
++)
59 poison_free(ht
->tbl_chunk
[i
]);
61 /* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
65 struct lttng_ust_lfht_node
*bucket_at(struct lttng_ust_lfht
*ht
, unsigned long index
)
67 unsigned long chunk
, offset
;
69 chunk
= index
>> ht
->min_alloc_buckets_order
;
70 offset
= index
& (ht
->min_nr_alloc_buckets
- 1);
71 return &ht
->tbl_chunk
[chunk
][offset
];
75 struct lttng_ust_lfht
*alloc_lttng_ust_lfht(unsigned long min_nr_alloc_buckets
,
76 unsigned long max_nr_buckets
)
78 unsigned long nr_chunks
, lttng_ust_lfht_size
;
80 min_nr_alloc_buckets
= max(min_nr_alloc_buckets
,
81 max_nr_buckets
/ MAX_CHUNK_TABLE
);
82 nr_chunks
= max_nr_buckets
/ min_nr_alloc_buckets
;
83 lttng_ust_lfht_size
= offsetof(struct lttng_ust_lfht
, tbl_chunk
) +
84 sizeof(struct lttng_ust_lfht_node
*) * nr_chunks
;
85 lttng_ust_lfht_size
= max(lttng_ust_lfht_size
, sizeof(struct lttng_ust_lfht
));
87 return __default_alloc_lttng_ust_lfht(
88 <tng_ust_lfht_mm_chunk
, lttng_ust_lfht_size
,
89 min_nr_alloc_buckets
, max_nr_buckets
);
92 const struct lttng_ust_lfht_mm_type lttng_ust_lfht_mm_chunk
= {
93 .alloc_lttng_ust_lfht
= alloc_lttng_ust_lfht
,
94 .alloc_bucket_table
= lttng_ust_lfht_alloc_bucket_table
,
95 .free_bucket_table
= lttng_ust_lfht_free_bucket_table
,
96 .bucket_at
= bucket_at
,