From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Mon, 27 May 2013 17:13:55 +0000 (-0400)
Subject: rcuja fix: list prev pointer vs recompaction
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=ade342cbaeff2436d44eb17899765cb64a1271ca;p=urcu.git

rcuja fix: list prev pointer vs recompaction

We should update the list prev pointer (for the first node) when a
recompaction changes the address of the list head. Currently a
work-around.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/rcuja/rcuja.c b/rcuja/rcuja.c
index d24aaad..9c90fdc 100644
--- a/rcuja/rcuja.c
+++ b/rcuja/rcuja.c
@@ -1419,6 +1419,10 @@ int ja_unchain_node(struct cds_ja *ja,
 	 * list (while holding lock).
 	 */
 	cds_hlist_for_each_rcu(hlist_node, &hlist_head) {
+		if (count == 0) {
+			/* FIXME: currently a work-around */
+			hlist_node->prev = (struct cds_hlist_node *) node_flag_ptr;
+		}
 		count++;
 		if (hlist_node == &node->list)
 			found++;
@@ -1429,6 +1433,10 @@ int ja_unchain_node(struct cds_ja *ja,
 		goto end;
 	}
 	cds_hlist_del_rcu(&node->list);
+	/*
+	 * Validate that we indeed removed the node from linked list.
+	 */
+	assert(ja_node_ptr(*node_flag_ptr) != (struct cds_ja_inode *) node);
 end:
 	rcuja_shadow_unlock(shadow_node);
 	return ret;