--- /dev/null
+#ifndef _URCU_RCULFHASH_INTERNAL_H
+#define _URCU_RCULFHASH_INTERNAL_H
+
+/*
+ * urcu/rculfhash-internal.h
+ *
+ * Internal header for Lock-Free RCU Hash Table
+ *
+ * Copyright 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright 2011 - Lai Jiangshan <laijs@cn.fujitsu.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "rculfhash.h"
+
+#ifdef DEBUG
+#define dbg_printf(fmt, args...) printf("[debug rculfhash] " fmt, ## args)
+#else
+#define dbg_printf(fmt, args...)
+#endif
+
+#if (CAA_BITS_PER_LONG == 32)
+#define MAX_TABLE_ORDER 32
+#else
+#define MAX_TABLE_ORDER 64
+#endif
+
+#define MAX_CHUNK_TABLE (1UL << 10)
+
+#ifndef min
+#define min(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
+#ifndef max
+#define max(a, b) ((a) > (b) ? (a) : (b))
+#endif
+
+struct ht_items_count;
+
+/*
+ * cds_lfht: Top-level data structure representing a lock-free hash
+ * table. Defined in the implementation file to make it be an opaque
+ * cookie to users.
+ *
+ * The fields used in fast-paths are placed near the end of the
+ * structure, because we need to have a variable-sized union to contain
+ * the mm plugin fields, which are used in the fast path.
+ */
+struct cds_lfht {
+ /* Initial configuration items */
+ unsigned long max_nr_buckets;
+ const struct cds_lfht_mm_type *mm; /* memory management plugin */
+ const struct rcu_flavor_struct *flavor; /* RCU flavor */
+
+ long count; /* global approximate item count */
+
+ /*
+ * We need to put the work threads offline (QSBR) when taking this
+ * mutex, because we use synchronize_rcu within this mutex critical
+ * section, which waits on read-side critical sections, and could
+ * therefore cause grace-period deadlock if we hold off RCU G.P.
+ * completion.
+ */
+ pthread_mutex_t resize_mutex; /* resize mutex: add/del mutex */
+ pthread_attr_t *resize_attr; /* Resize threads attributes */
+ unsigned int in_progress_resize, in_progress_destroy;
+ unsigned long resize_target;
+ int resize_initiated;
+
+ /*
+ * Variables needed for add and remove fast-paths.
+ */
+ int flags;
+ unsigned long min_alloc_buckets_order;
+ unsigned long min_nr_alloc_buckets;
+ struct ht_items_count *split_count; /* split item count */
+
+ /*
+ * Variables needed for the lookup, add and remove fast-paths.
+ */
+ unsigned long size; /* always a power of 2, shared (RCU) */
+ /*
+ * bucket_at pointer is kept here to skip the extra level of
+ * dereference needed to get to "mm" (this is a fast-path).
+ */
+ struct cds_lfht_node *(*bucket_at)(struct cds_lfht *ht,
+ unsigned long index);
+ /*
+ * Dynamic length "tbl_chunk" needs to be at the end of
+ * cds_lfht.
+ */
+ union {
+ /*
+ * Contains the per order-index-level bucket node table.
+ * The size of each bucket node table is half the number
+ * of hashes contained in this order (except for order 0).
+ * The minimum allocation buckets size parameter allows
+ * combining the bucket node arrays of the lowermost
+ * levels to improve cache locality for small index orders.
+ */
+ struct cds_lfht_node *tbl_order[MAX_TABLE_ORDER];
+
+ /*
+ * Contains the bucket node chunks. The size of each
+ * bucket node chunk is ->min_alloc_size (we avoid to
+ * allocate chunks with different size). Chunks improve
+ * cache locality for small index orders, and are more
+ * friendly with environments where allocation of large
+ * contiguous memory areas is challenging due to memory
+ * fragmentation concerns or inability to use virtual
+ * memory addressing.
+ */
+ struct cds_lfht_node *tbl_chunk[0];
+
+ /*
+ * Memory mapping with room for all possible buckets.
+ * Their memory is allocated when needed.
+ */
+ struct cds_lfht_node *tbl_mmap;
+ };
+ /*
+ * End of variables needed for the lookup, add and remove
+ * fast-paths.
+ */
+};
+
+extern unsigned int cds_lfht_fls_ulong(unsigned long x);
+extern int cds_lfht_get_count_order_ulong(unsigned long x);
+
+#ifdef POISON_FREE
+#define poison_free(ptr) \
+ do { \
+ if (ptr) { \
+ memset(ptr, 0x42, sizeof(*(ptr))); \
+ free(ptr); \
+ } \
+ } while (0)
+#else
+#define poison_free(ptr) free(ptr)
+#endif
+
+static inline
+struct cds_lfht *__default_alloc_cds_lfht(
+ const struct cds_lfht_mm_type *mm,
+ unsigned long cds_lfht_size,
+ unsigned long min_nr_alloc_buckets,
+ unsigned long max_nr_buckets)
+{
+ struct cds_lfht *ht;
+
+ ht = calloc(1, cds_lfht_size);
+ assert(ht);
+
+ ht->mm = mm;
+ ht->bucket_at = mm->bucket_at;
+ ht->min_nr_alloc_buckets = min_nr_alloc_buckets;
+ ht->min_alloc_buckets_order =
+ cds_lfht_get_count_order_ulong(min_nr_alloc_buckets);
+ ht->max_nr_buckets = max_nr_buckets;
+
+ return ht;
+}
+
+#endif /* _URCU_RCULFHASH_INTERNAL_H */
projects / lttng-tools.git / blobdiff