4 * Order based memory management for Lock-Free RCU Hash Table
6 * Copyright 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
7 * Copyright 2011 - Lai Jiangshan <laijs@cn.fujitsu.com>
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with this library; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 #include <urcu/assert.h>
25 #include <rculfhash-internal.h>
28 void cds_lfht_alloc_bucket_table(struct cds_lfht
*ht
, unsigned long order
)
31 ht
->tbl_order
[0] = calloc(ht
->min_nr_alloc_buckets
,
32 sizeof(struct cds_lfht_node
));
33 urcu_posix_assert(ht
->tbl_order
[0]);
34 } else if (order
> ht
->min_alloc_buckets_order
) {
35 ht
->tbl_order
[order
] = calloc(1UL << (order
-1),
36 sizeof(struct cds_lfht_node
));
37 urcu_posix_assert(ht
->tbl_order
[order
]);
39 /* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
43 * cds_lfht_free_bucket_table() should be called with decreasing order.
44 * When cds_lfht_free_bucket_table(0) is called, it means the whole
48 void cds_lfht_free_bucket_table(struct cds_lfht
*ht
, unsigned long order
)
51 poison_free(ht
->tbl_order
[0]);
52 else if (order
> ht
->min_alloc_buckets_order
)
53 poison_free(ht
->tbl_order
[order
]);
54 /* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
58 struct cds_lfht_node
*bucket_at(struct cds_lfht
*ht
, unsigned long index
)
62 if (index
< ht
->min_nr_alloc_buckets
) {
63 dbg_printf("bucket index %lu order 0 aridx 0\n", index
);
64 return &ht
->tbl_order
[0][index
];
67 * equivalent to cds_lfht_get_count_order_ulong(index + 1), but
68 * optimizes away the non-existing 0 special-case for
69 * cds_lfht_get_count_order_ulong.
71 order
= cds_lfht_fls_ulong(index
);
72 dbg_printf("bucket index %lu order %lu aridx %lu\n",
73 index
, order
, index
& ((1UL << (order
- 1)) - 1));
74 return &ht
->tbl_order
[order
][index
& ((1UL << (order
- 1)) - 1)];
78 struct cds_lfht
*alloc_cds_lfht(unsigned long min_nr_alloc_buckets
,
79 unsigned long max_nr_buckets
)
81 return __default_alloc_cds_lfht(
82 &cds_lfht_mm_order
, sizeof(struct cds_lfht
),
83 min_nr_alloc_buckets
, max_nr_buckets
);
86 const struct cds_lfht_mm_type cds_lfht_mm_order
= {
87 .alloc_cds_lfht
= alloc_cds_lfht
,
88 .alloc_bucket_table
= cds_lfht_alloc_bucket_table
,
89 .free_bucket_table
= cds_lfht_free_bucket_table
,
90 .bucket_at
= bucket_at
,