Merge branch 'master' into urcu/ht

[urcu.git] / urcu / rculfhash.h

diff --git a/urcu/rculfhash.h b/urcu/rculfhash.h
index ed75431f9864e08b9668e29b86f10496f8110253..40fe4df6bd763f81240b4d08d8bfa7047e344ec1 100644 (file)
--- a/urcu/rculfhash.h
+++ b/urcu/rculfhash.h
@@ -4,14 +4,26 @@
 #include <stdint.h>
 #include <urcu-call-rcu.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * struct rcu_ht_node and struct _rcu_ht_node should be aligned on
+ * 4-bytes boundaries because the two lower bits are used as flags.
+ */
+
+struct _rcu_ht_node {
+       struct rcu_ht_node *next;       /* ptr | DUMMY_FLAG | REMOVED_FLAG */
+       unsigned long reverse_hash;
+};
+
 struct rcu_ht_node {
-       struct rcu_ht_node *next;
+       /* cache-hot for iteration */
+       struct _rcu_ht_node p;          /* needs to be first field */
        void *key;
-       size_t key_len;
-       unsigned long hash;
-       unsigned long reverse_hash;
-       unsigned int dummy;
-       void *value;
+       unsigned int key_len;
+       /* cache-cold for iteration */
        struct rcu_head head;
 };
 
@@ -29,12 +41,10 @@ typedef unsigned long (*ht_compare_fct)(void *key1, size_t key1_len,
 
 static inline
 void ht_node_init(struct rcu_ht_node *node, void *key,
-                 size_t key_len, void *value)
+                 size_t key_len)
 {
        node->key = key;
        node->key_len = key_len;
-       node->value = value;
-       node->dummy = 0;
 }
 
 /*
@@ -48,6 +58,10 @@ struct rcu_ht *ht_new(ht_hash_fct hash_fct,
                                void (*func)(struct rcu_head *head)));
 
 int ht_destroy(struct rcu_ht *ht);
+/* 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. */
 struct rcu_ht_node *ht_lookup(struct rcu_ht *ht, void *key, size_t key_len);
@@ -55,12 +69,21 @@ 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);
 
-/* Call with rcu_read_lock held. */
-int ht_add_unique(struct rcu_ht *ht, struct rcu_ht_node *node);
+/*
+ * Call with rcu_read_lock held.
+ * 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.
+ */
+struct rcu_ht_node *ht_add_unique(struct rcu_ht *ht, struct rcu_ht_node *node);
 
 /* Call with rcu_read_lock held. */
 int ht_remove(struct rcu_ht *ht, struct rcu_ht_node *node);
 
 void ht_resize(struct rcu_ht *ht, int growth);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* _URCU_RCULFHASH_H */