--- /dev/null
+#ifndef _URCU_RCUJA_H
+#define _URCU_RCUJA_H
+
+/*
+ * urcu/rcuja.h
+ *
+ * Userspace RCU library - RCU Judy Array
+ *
+ * Copyright 2012-2013 - 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 this file _after_ including your URCU flavor.
+ */
+
+#include <urcu/compiler.h>
+#include <urcu-call-rcu.h>
+#include <urcu-flavor.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Duplicate nodes with the same key are chained into a singly-linked
+ * list. The last item of this list has a NULL next pointer.
+ */
+struct cds_ja_node {
+ struct cds_ja_node *next;
+};
+
+struct cds_ja;
+
+/*
+ * cds_ja_node_init - initialize a judy array node
+ * @node: the node to initialize.
+ *
+ * This function is kept to be eventually used for debugging purposes
+ * (detection of memory corruption).
+ */
+static inline
+void cds_ja_node_init(struct cds_ja_node *node)
+{
+}
+
+/*
+ * Note: key UINT64_MAX is reserved internally for iteration.
+ */
+
+/*
+ * cds_ja_lookup - look up by key.
+ * @ja: the Judy array.
+ * @key: key to look up.
+ *
+ * Returns the first node of a duplicate chain if a match is found, else
+ * returns NULL.
+ * A RCU read-side lock should be held across call to this function and
+ * use of its return value.
+ */
+struct cds_ja_node *cds_ja_lookup(struct cds_ja *ja, uint64_t key);
+
+/*
+ * cds_ja_lookup_below_equal - look up first node with key <= @key.
+ * @ja: the Judy array.
+ * @key: key to look up.
+ * @result_key: key found.
+ *
+ * Returns the first node of a duplicate chain if a node is present in
+ * the tree which has a key below or equal to @key, else returns NULL.
+ * A RCU read-side lock should be held across call to this function and
+ * use of its return value.
+ */
+struct cds_ja_node *cds_ja_lookup_below_equal(struct cds_ja *ja,
+ uint64_t key, uint64_t *result_key);
+
+/*
+ * cds_ja_lookup_above_equal - look up first node with key >= @key.
+ * @ja: the Judy array.
+ * @key: key to look up.
+ * @result_key: key found.
+ *
+ * Returns the first node of a duplicate chain if a node is present in
+ * the tree which has a key above or equal to @key, else returns NULL.
+ * A RCU read-side lock should be held across call to this function and
+ * use of its return value.
+ */
+struct cds_ja_node *cds_ja_lookup_above_equal(struct cds_ja *ja,
+ uint64_t key, uint64_t *result_key);
+
+/*
+ * cds_ja_add - Add @node at @key, allowing duplicates.
+ * @ja: the Judy array.
+ * @key: key at which @node should be added.
+ * @node: node to add.
+ *
+ * Returns 0 on success, negative error value on error.
+ * A RCU read-side lock should be held across call to this function.
+ */
+int cds_ja_add(struct cds_ja *ja, uint64_t key,
+ struct cds_ja_node *node);
+
+/*
+ * cds_ja_add_unique - Add @node at @key, without duplicates.
+ * @ja: the Judy array.
+ * @key: key at which @node should be added.
+ * @node: node to add.
+ *
+ * Returns @node if successfully added, else returns the already
+ * existing node (acts as a RCU lookup).
+ * A RCU read-side lock should be held across call to this function and
+ * use of its return value.
+ */
+struct cds_ja_node *cds_ja_add_unique(struct cds_ja *ja, uint64_t key,
+ struct cds_ja_node *node);
+
+/*
+ * cds_ja_del - Remove @node at @key.
+ * @ja: the Judy array.
+ * @key: key at which @node is expected.
+ * @node: node to remove.
+ *
+ * Returns 0 on success, negative error value on error.
+ * A RCU read-side lock should be held across call to this function.
+ */
+int cds_ja_del(struct cds_ja *ja, uint64_t key,
+ struct cds_ja_node *node);
+
+struct cds_ja *_cds_ja_new(unsigned int key_bits,
+ const struct rcu_flavor_struct *flavor);
+
+/*
+ * cds_ja_new - Create a Judy array.
+ * @key_bits: Number of bits for key.
+ *
+ * Returns non-NULL pointer on success, else NULL on error. @key_bits
+ * needs to be multiple of 8, either: 8, 16, 24, 32, 40, 48, 56, or 64.
+ */
+static inline
+struct cds_ja *cds_ja_new(unsigned int key_bits)
+{
+ return _cds_ja_new(key_bits, &rcu_flavor);
+}
+
+/*
+ * cds_ja_destroy - Destroy a Judy array.
+ * @ja: the Judy array.
+ *
+ * Returns 0 on success, negative error value on error.
+ * There should be no more concurrent add, delete, nor look-up performed
+ * on the Judy array while it is being destroyed (ensured by the caller).
+ * RCU read-side lock should _not_ be held when calling this function,
+ * however, QSBR threads need to be online.
+ */
+int cds_ja_destroy(struct cds_ja *ja);
+
+/*
+ * cds_ja_for_each_duplicate_rcu: Iterate through duplicates.
+ * @pos: struct cds_ja_node *, start of duplicate list and loop cursor.
+ *
+ * Iterate through duplicates returned by cds_ja_lookup*()
+ * This must be done while rcu_read_lock() is held.
+ * Receives a struct cds_ja_node * as parameter, which is used as start
+ * of duplicate list and loop cursor.
+ * _NOT_ safe against node removal within iteration.
+ */
+#define cds_ja_for_each_duplicate_rcu(pos) \
+ for (; (pos) != NULL; (pos) = rcu_dereference((pos)->next))
+
+/*
+ * cds_ja_for_each_duplicate_safe: Iterate through duplicates.
+ * @pos: struct cds_ja_node *, start of duplicate list and loop cursor.
+ * @p: struct cds_ja_node *, temporary pointer to next.
+ *
+ * Iterate through duplicates returned by cds_ja_lookup*().
+ * Safe against node removal within iteration.
+ * This must be done while rcu_read_lock() is held.
+ */
+#define cds_ja_for_each_duplicate_safe_rcu(pos, p) \
+ for (; (pos) != NULL ? \
+ ((p) = rcu_dereference((pos)->next), 1) : 0; \
+ (pos) = (p))
+
+/*
+ * cds_ja_for_each_key_rcu: Iterate over all keys in ascending order.
+ * @ja: Judy array on which iteration should be done.
+ * @key: Key cursor, needs to be a uint64_t.
+ * @pos: struct cds_ja_node *, used as loop cursor.
+ *
+ * Iterate over all keys of a RCU Judy array (_not_ duplicates) in
+ * ascending order.
+ * This must be done while rcu_read_lock() is held.
+ * Safe against node removal during iteration.
+ */
+#define cds_ja_for_each_key_rcu(ja, key, pos) \
+ for ((key) = 0; \
+ ((key) != UINT64_MAX ? \
+ ((pos) = cds_ja_lookup_above_equal(ja, key, &(key))) : 0); \
+ (key)++)
+
+/*
+ * cds_ja_for_each_key_prev_rcu: Iterate over all keys in descending order.
+ * @ja: Judy array on which iteration should be done.
+ * @key: Key cursor, needs to be a uint64_t.
+ * @pos: struct cds_ja_node *, used as loop cursor.
+ *
+ * Iterate over all keys of a RCU Judy array (_not_ duplicates) in
+ * descending order.
+ * This must be done while rcu_read_lock() is held.
+ * Safe against node removal during iteration.
+ */
+#define cds_ja_for_each_key_prev_rcu(ja, key, pos) \
+ for ((key) = UINT64_MAX - 1; \
+ ((key) != UINT64_MAX ? \
+ ((pos) = cds_ja_lookup_below_equal(ja, key, &(key))) : 0); \
+ (key)--)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _URCU_RCUJA_H */
projects / userspace-rcu.git / blobdiff