#include <pthread.h>
#ifdef DEBUG
-#define dbg_printf(fmt, args...) printf(fmt, ## args)
+#define dbg_printf(fmt, args...) printf("[debug rculfhash] " fmt, ## args)
#else
#define dbg_printf(fmt, args...)
#endif
uint32_t chain_len)
{
if (chain_len > 100)
- dbg_printf("rculfhash: WARNING: large chain length: %u.\n",
+ dbg_printf("WARNING: large chain length: %u.\n",
chain_len);
if (chain_len >= CHAIN_LEN_RESIZE_THRESHOLD)
ht_resize_lazy(ht, t,
{
unsigned long i, end_order;
- dbg_printf("rculfhash: init table: first_order %lu end_order %lu\n",
+ dbg_printf("init table: first_order %lu end_order %lu\n",
first_order, first_order + len_order);
end_order = first_order + len_order;
t->size = !first_order ? 0 : (1UL << (first_order - 1));
unsigned long j, len;
len = !i ? 1 : 1UL << (i - 1);
- dbg_printf("rculfhash: init order %lu len: %lu\n", i, len);
+ dbg_printf("init order %lu len: %lu\n", i, len);
t->tbl[i] = calloc(len, sizeof(struct _rcu_ht_node));
for (j = 0; j < len; j++) {
- dbg_printf("rculfhash: init entry: i %lu j %lu hash %lu\n",
+ dbg_printf("init entry: i %lu j %lu hash %lu\n",
i, j, !i ? 0 : (1UL << (i - 1)) + j);
struct rcu_ht_node *new_node =
(struct rcu_ht_node *) &t->tbl[i][j];
}
/* Update table size */
t->size = !i ? 1 : (1UL << i);
- dbg_printf("rculfhash: init new size: %lu\n", t->size);
+ dbg_printf("init new size: %lu\n", t->size);
if (CMM_LOAD_SHARED(ht->in_progress_destroy))
break;
}
index = hash & (t->size - 1);
order = get_count_order_ulong(index + 1);
lookup = &t->tbl[order][index & ((1UL << (order - 1)) - 1)];
- dbg_printf("rculfhash: lookup hash %lu index %lu order %lu aridx %lu\n",
+ dbg_printf("lookup hash %lu index %lu order %lu aridx %lu\n",
hash, index, order, index & ((1UL << (order - 1)) - 1));
node = (struct rcu_ht_node *) lookup;
for (;;) {
len = !order ? 1 : 1UL << (order - 1);
for (i = 0; i < len; i++) {
- dbg_printf("rculfhash: delete order %lu i %lu hash %lu\n",
+ dbg_printf("delete order %lu i %lu hash %lu\n",
order, i,
bit_reverse_ulong(t->tbl[order][i].reverse_hash));
assert(is_dummy(t->tbl[order][i].next));
(nr_dummy)++;
node = clear_flag(next);
} while (node);
- dbg_printf("rculfhash: number of dummy nodes: %lu\n", nr_dummy);
+ dbg_printf("number of dummy nodes: %lu\n", nr_dummy);
}
static
if (old_size == new_size)
return;
new_order = get_count_order_ulong(new_size) + 1;
- printf("rculfhash: resize from %lu (order %lu) to %lu (order %lu) buckets\n",
+ dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
old_size, old_order, new_size, new_order);
new_t = malloc(sizeof(struct rcu_table)
+ (new_order * sizeof(struct _rcu_ht_node *)));
struct rcu_table *t = rcu_dereference(ht->t);
unsigned long target_size;
+ if (growth < 0) {
+ /*
+ * Silently refuse to shrink hash table. (not supported)
+ */
+ dbg_printf("shrinking hash table not supported.\n");
+ return;
+ }
+
target_size = resize_target_update(t, growth);
if (t->size < target_size) {
CMM_STORE_SHARED(t->resize_initiated, 1);
#ifndef _URCU_RCULFHASH_H
#define _URCU_RCULFHASH_H
+/*
+ * urcu/rculfhash.h
+ *
+ * Userspace RCU library - Lock-Free RCU Hash Table
+ *
+ * Copyright 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.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 <stdint.h>
#include <urcu-call-rcu.h>
typedef unsigned long (*ht_compare_fct)(void *key1, size_t key1_len,
void *key2, size_t key2_len);
+/*
+ * ht_node_init - initialize a hash table node
+ */
static inline
void ht_node_init(struct rcu_ht_node *node, void *key,
size_t key_len)
}
/*
+ * ht_new - allocate a hash table.
+ *
* init_size must be power of two.
*/
struct rcu_ht *ht_new(ht_hash_fct hash_fct,
void (*ht_call_rcu)(struct rcu_head *head,
void (*func)(struct rcu_head *head)));
+/*
+ * ht_destroy - destroy a hash table.
+ */
int ht_destroy(struct rcu_ht *ht);
-/* Count the number of nodes in the hash table. Call with rcu_read_lock held. */
+
+/*
+ * ht_count_nodes - count the number of nodes in the hash table.
+ *
+ * Call with rcu_read_lock held.
+ */
void ht_count_nodes(struct rcu_ht *ht,
unsigned long *count,
unsigned long *removed);
-/* Call with rcu_read_lock held. */
+/*
+ * ht_lookup - lookup a node by key.
+ *
+ * Returns NULL if not found.
+ * Call with rcu_read_lock held.
+ */
struct rcu_ht_node *ht_lookup(struct rcu_ht *ht, void *key, size_t key_len);
-/* Call with rcu_read_lock held. */
-void ht_add(struct rcu_ht *ht, struct rcu_ht_node *node);
+/*
+ * ht_next - get the next item with same key (after a lookup).
+ *
+ * Returns NULL if no following node exists with same key.
+ * RCU read-side lock must be held across ht_lookup and ht_next calls, and also
+ * between ht_next calls using the node returned by a previous ht_next.
+ * Call with rcu_read_lock held.
+ */
+struct rcu_ht_node *ht_next(struct rcu_ht *ht, struct rcu_ht_node *node);
/*
+ * ht_add - add a node to the hash table.
+ *
* Call with rcu_read_lock held.
+ */
+void ht_add(struct rcu_ht *ht, struct rcu_ht_node *node);
+
+/*
+ * ht_add_unique - add a node to hash table, if key is not present.
+ *
* Returns the node added upon success.
* Returns the unique node already present upon failure. If ht_add_unique fails,
* the node passed as parameter should be freed by the caller.
+ * Call with rcu_read_lock held.
*/
struct rcu_ht_node *ht_add_unique(struct rcu_ht *ht, struct rcu_ht_node *node);
-/* Call with rcu_read_lock held. */
+/*
+ * ht_remove - remove node from hash table.
+ *
+ * Node can be looked up with ht_lookup. RCU read-side lock must be held between
+ * lookup and removal.
+ * Call with rcu_read_lock held.
+ */
int ht_remove(struct rcu_ht *ht, struct rcu_ht_node *node);
+/*
+ * ht_resize - Force a hash table resize
+ * @growth: growth order (current size is multiplied by 2^growth)
+ *
+ * Currently, only expand operation is supported (growth >= 0).
+ */
void ht_resize(struct rcu_ht *ht, int growth);
#ifdef __cplusplus