rculfhash-internal.h

   1 #ifndef _URCU_RCULFHASH_INTERNAL_H
   2 #define _URCU_RCULFHASH_INTERNAL_H
   3
   4 /*
   5  * urcu/rculfhash-internal.h
   6  *
   7  * Internal header for Lock-Free RCU Hash Table
   8  *
   9  * Copyright 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  10  * Copyright 2011 - Lai Jiangshan <laijs@cn.fujitsu.com>
  11  *
  12  * This library is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU Lesser General Public
  14  * License as published by the Free Software Foundation; either
  15  * version 2.1 of the License, or (at your option) any later version.
  16  *
  17  * This library is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  * Lesser General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public
  23  * License along with this library; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  25  */
  26
  27 #include <urcu/rculfhash.h>
  28
  29 #ifdef DEBUG
  30 #define dbg_printf(fmt, args...)     printf("[debug rculfhash] " fmt, ## args)
  31 #else
  32 #define dbg_printf(fmt, args...)
  33 #endif
  34
  35 #if (CAA_BITS_PER_LONG == 32)
  36 #define MAX_TABLE_ORDER                 32
  37 #else
  38 #define MAX_TABLE_ORDER                 64
  39 #endif
  40
  41 #ifndef min
  42 #define min(a, b)       ((a) < (b) ? (a) : (b))
  43 #endif
  44
  45 #ifndef max
  46 #define max(a, b)       ((a) > (b) ? (a) : (b))
  47 #endif
  48
  49 struct ht_items_count;
  50
  51 /*
  52  * cds_lfht: Top-level data structure representing a lock-free hash
  53  * table. Defined in the implementation file to make it be an opaque
  54  * cookie to users.
  55  */
  56 struct cds_lfht {
  57         unsigned long size;     /* always a power of 2, shared (RCU) */
  58         int flags;
  59
  60         /*
  61          * We need to put the work threads offline (QSBR) when taking this
  62          * mutex, because we use synchronize_rcu within this mutex critical
  63          * section, which waits on read-side critical sections, and could
  64          * therefore cause grace-period deadlock if we hold off RCU G.P.
  65          * completion.
  66          */
  67         pthread_mutex_t resize_mutex;   /* resize mutex: add/del mutex */
  68         pthread_attr_t *resize_attr;    /* Resize threads attributes */
  69         unsigned int in_progress_resize, in_progress_destroy;
  70         unsigned long resize_target;
  71         int resize_initiated;
  72         const struct rcu_flavor_struct *flavor;
  73
  74         long count;                     /* global approximate item count */
  75         struct ht_items_count *split_count;     /* split item count */
  76
  77         /* memory management related fields are located at the end */
  78         const struct cds_lfht_mm_type *mm;
  79
  80         unsigned long min_alloc_buckets_order;
  81         unsigned long min_nr_alloc_buckets;
  82         unsigned long max_nr_buckets;
  83
  84         struct cds_lfht_node *(*bucket_at)(struct cds_lfht *ht,
  85                         unsigned long index);
  86
  87         union {
  88                 /*
  89                  * Contains the per order-index-level bucket node table.
  90                  * The size of each bucket node table is half the number
  91                  * of hashes contained in this order (except for order 0).
  92                  * The minimum allocation buckets size parameter allows
  93                  * combining the bucket node arrays of the lowermost
  94                  * levels to improve cache locality for small index orders.
  95                  */
  96                 struct cds_lfht_node *tbl_order[MAX_TABLE_ORDER];
  97         };
  98 };
  99
 100 extern unsigned int fls_ulong(unsigned long x);
 101 extern int get_count_order_ulong(unsigned long x);
 102
 103 #ifdef POISON_FREE
 104 #define poison_free(ptr)                                        \
 105         do {                                                    \
 106                 if (ptr) {                                      \
 107                         memset(ptr, 0x42, sizeof(*(ptr)));      \
 108                         free(ptr);                              \
 109                 }                                               \
 110         } while (0)
 111 #else
 112 #define poison_free(ptr)        free(ptr)
 113 #endif
 114
 115 #endif /* _URCU_RCULFHASH_INTERNAL_H */