*
* The old entry will be replaced with the new entry atomically.
*/
-static inline void list_replace_rcu(struct list_head *old, struct list_head *new){
+static inline void list_replace_rcu(struct list_head *old,
+ struct list_head *new)
+{
new->next = old->next;
new->prev = old->prev;
smp_wmb();
new->next->prev = new;
new->prev->next = new;
+ old->prev = LIST_POISON2;
}
/**
* as long as the traversal is guarded by rcu_read_lock().
*/
#define list_for_each_rcu(pos, head) \
- for (pos = (head)->next; prefetch(pos->next), pos != (head); \
- pos = rcu_dereference(pos->next))
+ for (pos = (head)->next; \
+ prefetch(rcu_dereference(pos)->next), pos != (head); \
+ pos = pos->next)
#define __list_for_each_rcu(pos, head) \
- for (pos = (head)->next; pos != (head); \
- pos = rcu_dereference(pos->next))
+ for (pos = (head)->next; \
+ rcu_dereference(pos) != (head); \
+ pos = pos->next)
/**
* list_for_each_safe_rcu - iterate over an rcu-protected list safe
* as long as the traversal is guarded by rcu_read_lock().
*/
#define list_for_each_safe_rcu(pos, n, head) \
- for (pos = (head)->next, n = pos->next; pos != (head); \
- pos = rcu_dereference(n), n = pos->next)
+ for (pos = (head)->next; \
+ n = rcu_dereference(pos)->next, pos != (head); \
+ pos = n)
/**
* list_for_each_entry_rcu - iterate over rcu list of given type
* the _rcu list-mutation primitives such as list_add_rcu()
* as long as the traversal is guarded by rcu_read_lock().
*/
-#define list_for_each_entry_rcu(pos, head, member) \
- for (pos = list_entry((head)->next, typeof(*pos), member); \
- prefetch(pos->member.next), &pos->member != (head); \
- pos = rcu_dereference(list_entry(pos->member.next, \
- typeof(*pos), member)))
+#define list_for_each_entry_rcu(pos, head, member) \
+ for (pos = list_entry((head)->next, typeof(*pos), member); \
+ prefetch(rcu_dereference(pos)->member.next), \
+ &pos->member != (head); \
+ pos = list_entry(pos->member.next, typeof(*pos), member))
/**
* as long as the traversal is guarded by rcu_read_lock().
*/
#define list_for_each_continue_rcu(pos, head) \
- for ((pos) = (pos)->next; prefetch((pos)->next), (pos) != (head); \
- (pos) = rcu_dereference((pos)->next))
+ for ((pos) = (pos)->next; \
+ prefetch(rcu_dereference((pos))->next), (pos) != (head); \
+ (pos) = (pos)->next)
/*
* Double linked lists with a single pointer list head.
}
}
+/*
+ * hlist_replace_rcu - replace old entry by new one
+ * @old : the element to be replaced
+ * @new : the new element to insert
+ *
+ * The old entry will be replaced with the new entry atomically.
+ */
+static inline void hlist_replace_rcu(struct hlist_node *old,
+ struct hlist_node *new)
+{
+ struct hlist_node *next = old->next;
+
+ new->next = next;
+ new->pprev = old->pprev;
+ smp_wmb();
+ if (next)
+ new->next->pprev = &new->next;
+ *new->pprev = new;
+ old->pprev = LIST_POISON2;
+}
+
static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
{
struct hlist_node *first = h->first;
* or hlist_del_rcu(), running on this same list.
* However, it is perfectly legal to run concurrently with
* the _rcu list-traversal primitives, such as
- * hlist_for_each_rcu(), used to prevent memory-consistency
+ * hlist_for_each_entry_rcu(), used to prevent memory-consistency
* problems on Alpha CPUs. Regardless of the type of CPU, the
* list-traversal primitive must be guarded by rcu_read_lock().
*/
* or hlist_del_rcu(), running on this same list.
* However, it is perfectly legal to run concurrently with
* the _rcu list-traversal primitives, such as
- * hlist_for_each_rcu(), used to prevent memory-consistency
+ * hlist_for_each_entry_rcu(), used to prevent memory-consistency
* problems on Alpha CPUs.
*/
static inline void hlist_add_before_rcu(struct hlist_node *n,
* or hlist_del_rcu(), running on this same list.
* However, it is perfectly legal to run concurrently with
* the _rcu list-traversal primitives, such as
- * hlist_for_each_rcu(), used to prevent memory-consistency
+ * hlist_for_each_entry_rcu(), used to prevent memory-consistency
* problems on Alpha CPUs.
*/
static inline void hlist_add_after_rcu(struct hlist_node *prev,
for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \
pos = n)
-#define hlist_for_each_rcu(pos, head) \
- for ((pos) = (head)->first; pos && ({ prefetch((pos)->next); 1; }); \
- (pos) = rcu_dereference((pos)->next))
-
/**
* hlist_for_each_entry - iterate over list of given type
* @tpos: the type * to use as a loop counter.
/**
* hlist_for_each_entry_rcu - iterate over rcu list of given type
- * @pos: the type * to use as a loop counter.
+ * @tpos: the type * to use as a loop counter.
* @pos: the &struct hlist_node to use as a loop counter.
* @head: the head for your list.
* @member: the name of the hlist_node within the struct.
*/
#define hlist_for_each_entry_rcu(tpos, pos, head, member) \
for (pos = (head)->first; \
- pos && ({ prefetch(pos->next); 1;}) && \
+ rcu_dereference(pos) && ({ prefetch(pos->next); 1;}) && \
({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
- pos = rcu_dereference(pos->next))
+ pos = pos->next)
#else
#warning "don't include kernel headers in userspace"
git.openpandora.org / pandora-kernel.git / blobdiff