From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Sat, 18 Oct 2014 16:33:39 +0000 (+0200)
Subject: rculist: allow reverse RCU traversal
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=bf02499bae889e418cfda14a0bab9f65c72410bb;p=userspace-rcu.git

rculist: allow reverse RCU traversal

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

diff --git a/urcu/rculist.h b/urcu/rculist.h
index 1fd2df3..9a01dad 100644
--- a/urcu/rculist.h
+++ b/urcu/rculist.h
@@ -35,8 +35,8 @@ void cds_list_add_rcu(struct cds_list_head *newp, struct cds_list_head *head)
 {
 	newp->next = head->next;
 	newp->prev = head;
-	head->next->prev = newp;
-	rcu_assign_pointer(head->next, newp);
+	rcu_assign_pointer(head->next->prev, newp);
+	CMM_STORE_SHARED(head->next, newp);
 }
 
 /* Add new element at the tail of the list. */
@@ -47,7 +47,7 @@ void cds_list_add_tail_rcu(struct cds_list_head *newp,
 	newp->next = head;
 	newp->prev = head->prev;
 	rcu_assign_pointer(head->prev->next, newp);
-	head->prev = newp;
+	CMM_STORE_SHARED(head->prev, newp);
 }
 
 /*
@@ -61,14 +61,14 @@ void cds_list_replace_rcu(struct cds_list_head *old, struct cds_list_head *_new)
 	_new->next = old->next;
 	_new->prev = old->prev;
 	rcu_assign_pointer(_new->prev->next, _new);
-	_new->next->prev = _new;
+	CMM_STORE_SHARED(_new->next->prev, _new);
 }
 
 /* Remove element from list. */
 static inline
 void cds_list_del_rcu(struct cds_list_head *elem)
 {
-	elem->next->prev = elem->prev;
+	CMM_STORE_SHARED(elem->next->prev, elem->prev);
 	CMM_STORE_SHARED(elem->prev->next, elem->next);
 }