diff options
| -rw-r--r-- | include/linux/rculist.h | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/include/linux/rculist.h b/include/linux/rculist.h index 8214cdc715f2..67867e0d4cec 100644 --- a/include/linux/rculist.h +++ b/include/linux/rculist.h @@ -506,6 +506,27 @@ static inline void hlist_replace_rcu(struct hlist_node *old, WRITE_ONCE(old->pprev, LIST_POISON2); } +/** + * hlists_swap_heads_rcu - swap the lists the hlist heads point to + * @left: The hlist head on the left + * @right: The hlist head on the right + * + * The lists start out as [@left ][node1 ... ] and + [@right ][node2 ... ] + * The lists end up as [@left ][node2 ... ] + * [@right ][node1 ... ] + */ +static inline void hlists_swap_heads_rcu(struct hlist_head *left, struct hlist_head *right) +{ + struct hlist_node *node1 = left->first; + struct hlist_node *node2 = right->first; + + rcu_assign_pointer(left->first, node2); + rcu_assign_pointer(right->first, node1); + WRITE_ONCE(node2->pprev, &left->first); + WRITE_ONCE(node1->pprev, &right->first); +} + /* * return the first or the next element in an RCU protected hlist */ |