X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=urcu-ht.c;h=7213c39ce1414d788149dc864f9114bcb814acb0;hb=3df2df75972d2ccaa1a1fa01bad06b0eda7f76f2;hp=500b8d36fff51dffaa3d2b8548b70f83be60518e;hpb=e0ba718a906a70053d699a25c1d59b5bbdbf8715;p=urcu.git

diff --git a/urcu-ht.c b/urcu-ht.c
index 500b8d3..7213c39 100644
--- a/urcu-ht.c
+++ b/urcu-ht.c
@@ -17,13 +17,16 @@
 #include <urcu/jhash.h>
 #include <urcu-ht.h>
 
+/* node flags */
+#define	NODE_STOLEN	(1 << 0)
+
 struct rcu_ht_node;
 
 struct rcu_ht_node {
 	struct rcu_ht_node *next;
 	void *key;
 	void *data;
-	int stolen;
+	unsigned int flags;
 };
 
 struct rcu_ht {
@@ -95,7 +98,7 @@ int ht_add(struct rcu_ht *ht, void *key, void *data)
 	new_head = calloc(1, sizeof(struct rcu_ht_node));
 	new_head->key = key;
 	new_head->data = data;
-	new_head->stolen = 0;
+	new_head->flags = 0;
 	/* here comes the fun and tricky part.
 	 * Add at the beginning with a cmpxchg.
 	 * Hold a read lock between the moment the first element is read
@@ -174,9 +177,15 @@ retry:
 		node = rcu_dereference(*prev);
 	}
 
-	/* Another concurrent thread stole it ? If so, let it deal with this. */
-	if (cmpxchg(&node->stolen, 0, 1) != 0)
-		goto error;
+	if (!del_node) {
+		/*
+		 * Another concurrent thread stole it ? If so, let it deal with
+		 * this. Assume NODE_STOLEN is the only flag. If this changes,
+		 * read flags before cmpxchg.
+		 */
+		if (cmpxchg(&node->flags, 0, NODE_STOLEN) != 0)
+			goto error;
+	}
 
 	/* Found it ! pointer to object is in "prev" */
 	if (rcu_cmpxchg_pointer(prev, node, node->next) == node)