X-Git-Url: https://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=rculfhash.c;h=be995dfeaf5ef70795a6fd74a7bc34f4ced558c6;hp=d733d6bd53da2cab4b849e343656ce53df4326f7;hb=3fb86f26cfea354e44be1099642fc88436e3edf3;hpb=960c9e4ff8e6028f5a0d4b1c1d747b20f08c5177

diff --git a/rculfhash.c b/rculfhash.c
index d733d6b..be995df 100644
--- a/rculfhash.c
+++ b/rculfhash.c
@@ -724,7 +724,12 @@ struct _cds_lfht_node *lookup_bucket(struct cds_lfht *ht, unsigned long size,
 
 	assert(size > 0);
 	index = hash & (size - 1);
-	order = get_count_order_ulong(index + 1);
+	/*
+	 * equivalent to get_count_order_ulong(index + 1), but optimizes
+	 * away the non-existing 0 special-case for
+	 * get_count_order_ulong.
+	 */
+	order = fls_ulong(index);
 
 	dbg_printf("lookup hash %lu index %lu order %lu aridx %lu\n",
 		   hash, index, order, index & (!order ? 0 : ((1UL << (order - 1)) - 1)));
@@ -782,10 +787,10 @@ void _cds_lfht_gc_bucket(struct cds_lfht_node *dummy, struct cds_lfht_node *node
 static
 int _cds_lfht_replace(struct cds_lfht *ht, unsigned long size,
 		struct cds_lfht_node *old_node,
-		struct cds_lfht_node *ret_next,
+		struct cds_lfht_node *old_next,
 		struct cds_lfht_node *new_node)
 {
-	struct cds_lfht_node *dummy, *old_next;
+	struct cds_lfht_node *dummy, *ret_next;
 	struct _cds_lfht_node *lookup;
 	int flagged = 0;
 
@@ -797,9 +802,8 @@ int _cds_lfht_replace(struct cds_lfht *ht, unsigned long size,
 	assert(!is_removed(new_node));
 	assert(!is_dummy(new_node));
 	assert(new_node != old_node);
-	do {
+	for (;;) {
 		/* Insert after node to be replaced */
-		old_next = ret_next;
 		if (is_removed(old_next)) {
 			/*
 			 * Too late, the old node has been removed under us
@@ -822,7 +826,10 @@ int _cds_lfht_replace(struct cds_lfht *ht, unsigned long size,
 		 */
 		ret_next = uatomic_cmpxchg(&old_node->p.next,
 			      old_next, flag_removed(new_node));
-	} while (ret_next != old_next);
+		if (ret_next == old_next)
+			break;
+		old_next = ret_next;
+	}
 
 	/* We performed the replacement. */
 	flagged = 1;
@@ -882,11 +889,15 @@ struct cds_lfht_node *_cds_lfht_add(struct cds_lfht *ht,
 				goto insert;
 			if (likely(clear_flag(iter)->p.reverse_hash > node->p.reverse_hash))
 				goto insert;
+			/* dummy node is the first node of the identical-hash-value chain */
+			if (dummy && clear_flag(iter)->p.reverse_hash == node->p.reverse_hash)
+				goto insert;
 			next = rcu_dereference(clear_flag(iter)->p.next);
 			if (unlikely(is_removed(next)))
 				goto gc_node;
 			if ((mode == ADD_UNIQUE || mode == ADD_REPLACE)
 			    && !is_dummy(next)
+			    && clear_flag(iter)->p.reverse_hash == node->p.reverse_hash
 			    && !ht->compare_fct(node->key, node->key_len,
 						clear_flag(iter)->key,
 						clear_flag(iter)->key_len)) {
@@ -1336,6 +1347,7 @@ void cds_lfht_lookup(struct cds_lfht *ht, void *key, size_t key_len,
 		next = rcu_dereference(node->p.next);
 		if (likely(!is_removed(next))
 		    && !is_dummy(next)
+		    && clear_flag(node)->p.reverse_hash == reverse_hash
 		    && likely(!ht->compare_fct(node->key, node->key_len, key, key_len))) {
 				break;
 		}