#include <linux/stddef.h>
#include <linux/prefetch.h>
+#include <linux/kernel.h>
#include <asm/system.h>
+#include <asm/bug.h>
/*
* These are non-NULL pointers that will result in page faults
#define LIST_HEAD(name) \
struct list_head name = LIST_HEAD_INIT(name)
-#define INIT_LIST_HEAD(ptr) do { \
- (ptr)->next = (ptr); (ptr)->prev = (ptr); \
-} while (0)
+static inline void INIT_LIST_HEAD(struct list_head *list)
+{
+ list->next = list;
+ list->prev = list;
+}
/*
* Insert a new entry between two known consecutive entries.
struct list_head *prev,
struct list_head *next)
{
+ if (next->prev != prev) {
+ printk("List corruption. next->prev should be %p, but was %p\n",
+ prev, next->prev);
+ BUG();
+ }
+ if (prev->next != next) {
+ printk("List corruption. prev->next should be %p, but was %p\n",
+ next, prev->next);
+ BUG();
+ }
next->prev = new;
new->next = next;
new->prev = prev;
*/
static inline void list_del(struct list_head *entry)
{
+ if (entry->prev->next != entry) {
+ printk("List corruption. prev->next should be %p, but was %p\n",
+ entry, entry->prev->next);
+ BUG();
+ }
+ if (entry->next->prev != entry) {
+ printk("List corruption. next->prev should be %p, but was %p\n",
+ entry, entry->next->prev);
+ BUG();
+ }
__list_del(entry->prev, entry->next);
entry->next = LIST_POISON1;
entry->prev = LIST_POISON2;
* list_for_each_entry_rcu().
*
* Note that the caller is not permitted to immediately free
- * the newly deleted entry. Instead, either synchronize_kernel()
+ * the newly deleted entry. Instead, either synchronize_rcu()
* or call_rcu() must be used to defer freeing until an RCU
* grace period has elapsed.
*/
*
* 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;
}
/**
prefetch(pos->member.next), &pos->member != (head); \
pos = list_entry(pos->member.next, typeof(*pos), member))
+/**
+ * list_for_each_entry_from - iterate over list of given type
+ * continuing from existing point
+ * @pos: the type * to use as a loop counter.
+ * @head: the head for your list.
+ * @member: the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_from(pos, head, member) \
+ for (; prefetch(pos->member.next), &pos->member != (head); \
+ pos = list_entry(pos->member.next, typeof(*pos), member))
+
/**
* list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
* @pos: the type * to use as a loop counter.
&pos->member != (head); \
pos = n, n = list_entry(n->member.next, typeof(*n), member))
+/**
+ * list_for_each_entry_safe_continue - iterate over list of given type
+ * continuing after existing point safe against removal of list entry
+ * @pos: the type * to use as a loop counter.
+ * @n: another type * to use as temporary storage
+ * @head: the head for your list.
+ * @member: the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_safe_continue(pos, n, head, member) \
+ for (pos = list_entry(pos->member.next, typeof(*pos), member), \
+ n = list_entry(pos->member.next, typeof(*pos), member); \
+ &pos->member != (head); \
+ pos = n, n = list_entry(n->member.next, typeof(*n), member))
+
+/**
+ * list_for_each_entry_safe_from - iterate over list of given type
+ * from existing point safe against removal of list entry
+ * @pos: the type * to use as a loop counter.
+ * @n: another type * to use as temporary storage
+ * @head: the head for your list.
+ * @member: the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_safe_from(pos, n, head, member) \
+ for (n = list_entry(pos->member.next, typeof(*pos), member); \
+ &pos->member != (head); \
+ pos = n, n = list_entry(n->member.next, typeof(*n), member))
+
+/**
+ * list_for_each_entry_safe_reverse - iterate backwards over list of given type safe against
+ * removal of list entry
+ * @pos: the type * to use as a loop counter.
+ * @n: another type * to use as temporary storage
+ * @head: the head for your list.
+ * @member: the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_safe_reverse(pos, n, head, member) \
+ for (pos = list_entry((head)->prev, typeof(*pos), member), \
+ n = list_entry(pos->member.prev, typeof(*pos), member); \
+ &pos->member != (head); \
+ pos = n, n = list_entry(n->member.prev, typeof(*n), member))
+
/**
* list_for_each_rcu - iterate over an rcu-protected list
* @pos: the &struct list_head to use as a loop counter.
* 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.
#define HLIST_HEAD_INIT { .first = NULL }
#define HLIST_HEAD(name) struct hlist_head name = { .first = NULL }
#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL)
-#define INIT_HLIST_NODE(ptr) ((ptr)->next = NULL, (ptr)->pprev = NULL)
+static inline void INIT_HLIST_NODE(struct hlist_node *h)
+{
+ h->next = NULL;
+ h->pprev = NULL;
+}
static inline int hlist_unhashed(const struct hlist_node *h)
{
static inline void hlist_del_init(struct hlist_node *n)
{
- if (n->pprev) {
+ if (!hlist_unhashed(n)) {
__hlist_del(n);
INIT_HLIST_NODE(n);
}
}
+/*
+ * 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().
*/
next->next->pprev = &next->next;
}
+/**
+ * hlist_add_before_rcu - adds the specified element to the specified hlist
+ * before the specified node while permitting racing traversals.
+ * @n: the new element to add to the hash list.
+ * @next: the existing element to add the new element before.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as hlist_add_head_rcu()
+ * 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_entry_rcu(), used to prevent memory-consistency
+ * problems on Alpha CPUs.
+ */
+static inline void hlist_add_before_rcu(struct hlist_node *n,
+ struct hlist_node *next)
+{
+ n->pprev = next->pprev;
+ n->next = next;
+ smp_wmb();
+ next->pprev = &n->next;
+ *(n->pprev) = n;
+}
+
+/**
+ * hlist_add_after_rcu - adds the specified element to the specified hlist
+ * after the specified node while permitting racing traversals.
+ * @prev: the existing element to add the new element after.
+ * @n: the new element to add to the hash list.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as hlist_add_head_rcu()
+ * 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_entry_rcu(), used to prevent memory-consistency
+ * problems on Alpha CPUs.
+ */
+static inline void hlist_add_after_rcu(struct hlist_node *prev,
+ struct hlist_node *n)
+{
+ n->next = prev->next;
+ n->pprev = &prev->next;
+ smp_wmb();
+ prev->next = n;
+ if (n->next)
+ n->next->pprev = &n->next;
+}
+
#define hlist_entry(ptr, type, member) container_of(ptr,type,member)
#define hlist_for_each(pos, head) \
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://git.onelab.eu / linux-2.6.git / blobdiff