#ifdef __KERNEL__
#include <linux/stddef.h>
+#include <linux/poison.h>
#include <linux/prefetch.h>
#include <asm/system.h>
/*
- * These are non-NULL pointers that will result in page faults
- * under normal circumstances, used to verify that nobody uses
- * non-initialized list entries.
- */
-#define LIST_POISON1 ((void *) 0x00100100)
-#define LIST_POISON2 ((void *) 0x00200200)
-
-/*
* Simple doubly linked list implementation.
*
* Some of the internal functions ("__xxx") are useful when
* This is only for internal list manipulation where we know
* the prev/next entries already!
*/
+#ifndef CONFIG_DEBUG_LIST
static inline void __list_add(struct list_head *new,
struct list_head *prev,
struct list_head *next)
new->prev = prev;
prev->next = new;
}
+#else
+extern void __list_add(struct list_head *new,
+ struct list_head *prev,
+ struct list_head *next);
+#endif
/**
* list_add - add a new entry
* Insert a new entry after the specified head.
* This is good for implementing stacks.
*/
+#ifndef CONFIG_DEBUG_LIST
static inline void list_add(struct list_head *new, struct list_head *head)
{
__list_add(new, head, head->next);
}
+#else
+extern void list_add(struct list_head *new, struct list_head *head);
+#endif
+
/**
* list_add_tail - add a new entry
/**
* list_del - deletes entry from list.
* @entry: the element to delete from the list.
- * Note: list_empty on entry does not return true after this, the entry is
+ * Note: list_empty() on entry does not return true after this, the entry is
* in an undefined state.
*/
+#ifndef CONFIG_DEBUG_LIST
static inline void list_del(struct list_head *entry)
{
__list_del(entry->prev, entry->next);
entry->next = LIST_POISON1;
entry->prev = LIST_POISON2;
}
+#else
+extern void list_del(struct list_head *entry);
+#endif
/**
* list_del_rcu - deletes entry from list without re-initialization
* @entry: the element to delete from the list.
*
- * Note: list_empty on entry does not return true after this,
+ * Note: list_empty() on entry does not return true after this,
* the entry is in an undefined state. It is useful for RCU based
* lockfree traversal.
*
* list_replace - replace old entry by new one
* @old : the element to be replaced
* @new : the new element to insert
- * Note: if 'old' was empty, it will be overwritten.
+ *
+ * If @old was empty, it will be overwritten.
*/
static inline void list_replace(struct list_head *old,
struct list_head *new)
INIT_LIST_HEAD(old);
}
-/*
+/**
* list_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.
- * Note: 'old' should not be empty.
+ * The @old entry will be replaced with the @new entry atomically.
+ * Note: @old should not be empty.
*/
static inline void list_replace_rcu(struct list_head *old,
struct list_head *new)
}
/**
+ * list_is_last - tests whether @list is the last entry in list @head
+ * @list: the entry to test
+ * @head: the head of the list
+ */
+static inline int list_is_last(const struct list_head *list,
+ const struct list_head *head)
+{
+ return list->next == head;
+}
+
+/**
* list_empty - tests whether a list is empty
* @head: the list to test.
*/
}
/**
+ * list_splice_init_rcu - splice an RCU-protected list into an existing list.
+ * @list: the RCU-protected list to splice
+ * @head: the place in the list to splice the first list into
+ * @sync: function to sync: synchronize_rcu(), synchronize_sched(), ...
+ *
+ * @head can be RCU-read traversed concurrently with this function.
+ *
+ * Note that this function blocks.
+ *
+ * Important note: the caller must take whatever action is necessary to
+ * prevent any other updates to @head. In principle, it is possible
+ * to modify the list as soon as sync() begins execution.
+ * If this sort of thing becomes necessary, an alternative version
+ * based on call_rcu() could be created. But only if -really-
+ * needed -- there is no shortage of RCU API members.
+ */
+static inline void list_splice_init_rcu(struct list_head *list,
+ struct list_head *head,
+ void (*sync)(void))
+{
+ struct list_head *first = list->next;
+ struct list_head *last = list->prev;
+ struct list_head *at = head->next;
+
+ if (list_empty(head))
+ return;
+
+ /* "first" and "last" tracking list, so initialize it. */
+
+ INIT_LIST_HEAD(list);
+
+ /*
+ * At this point, the list body still points to the source list.
+ * Wait for any readers to finish using the list before splicing
+ * the list body into the new list. Any new readers will see
+ * an empty list.
+ */
+
+ sync();
+
+ /*
+ * Readers are finished with the source list, so perform splice.
+ * The order is important if the new list is global and accessible
+ * to concurrent RCU readers. Note that RCU readers are not
+ * permitted to traverse the prev pointers without excluding
+ * this function.
+ */
+
+ last->next = at;
+ smp_wmb();
+ head->next = first;
+ first->prev = head;
+ at->prev = last;
+}
+
+/**
* list_entry - get the struct for this entry
* @ptr: the &struct list_head pointer.
* @type: the type of the struct this is embedded in.
container_of(ptr, type, member)
/**
+ * list_first_entry - get the first element from a list
+ * @ptr: the list head to take the element from.
+ * @type: the type of the struct this is embedded in.
+ * @member: the name of the list_struct within the struct.
+ *
+ * Note, that list is expected to be not empty.
+ */
+#define list_first_entry(ptr, type, member) \
+ list_entry((ptr)->next, type, member)
+
+/**
* list_for_each - iterate over a list
- * @pos: the &struct list_head to use as a loop counter.
+ * @pos: the &struct list_head to use as a loop cursor.
* @head: the head for your list.
*/
#define list_for_each(pos, head) \
/**
* __list_for_each - iterate over a list
- * @pos: the &struct list_head to use as a loop counter.
+ * @pos: the &struct list_head to use as a loop cursor.
* @head: the head for your list.
*
* This variant differs from list_for_each() in that it's the
/**
* list_for_each_prev - iterate over a list backwards
- * @pos: the &struct list_head to use as a loop counter.
+ * @pos: the &struct list_head to use as a loop cursor.
* @head: the head for your list.
*/
#define list_for_each_prev(pos, head) \
/**
* list_for_each_safe - iterate over a list safe against removal of list entry
- * @pos: the &struct list_head to use as a loop counter.
+ * @pos: the &struct list_head to use as a loop cursor.
* @n: another &struct list_head to use as temporary storage
* @head: the head for your list.
*/
/**
* list_for_each_entry - iterate over list of given type
- * @pos: the type * to use as a loop counter.
+ * @pos: the type * to use as a loop cursor.
* @head: the head for your list.
* @member: the name of the list_struct within the struct.
*/
/**
* list_for_each_entry_reverse - iterate backwards over list of given type.
- * @pos: the type * to use as a loop counter.
+ * @pos: the type * to use as a loop cursor.
* @head: the head for your list.
* @member: the name of the list_struct within the struct.
*/
pos = list_entry(pos->member.prev, typeof(*pos), member))
/**
- * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue
+ * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue()
* @pos: the type * to use as a start point
* @head: the head of the list
* @member: the name of the list_struct within the struct.
*
- * Prepares a pos entry for use as a start point in list_for_each_entry_continue.
+ * Prepares a pos entry for use as a start point in list_for_each_entry_continue().
*/
#define list_prepare_entry(pos, head, member) \
((pos) ? : list_entry(head, typeof(*pos), member))
/**
* list_for_each_entry_continue - continue iteration over list of given type
- * @pos: the type * to use as a loop counter.
+ * @pos: the type * to use as a loop cursor.
* @head: the head for your list.
* @member: the name of the list_struct within the struct.
*
/**
* list_for_each_entry_from - iterate over list of given type from the current point
- * @pos: the type * to use as a loop counter.
+ * @pos: the type * to use as a loop cursor.
* @head: the head for your list.
* @member: the name of the list_struct within the struct.
*
/**
* 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: the type * to use as a loop cursor.
* @n: another type * to use as temporary storage
* @head: the head for your list.
* @member: the name of the list_struct within the struct.
/**
* list_for_each_entry_safe_continue
- * @pos: the type * to use as a loop counter.
+ * @pos: the type * to use as a loop cursor.
* @n: another type * to use as temporary storage
* @head: the head for your list.
* @member: the name of the list_struct within the struct.
/**
* list_for_each_entry_safe_from
- * @pos: the type * to use as a loop counter.
+ * @pos: the type * to use as a loop cursor.
* @n: another type * to use as temporary storage
* @head: the head for your list.
* @member: the name of the list_struct within the struct.
/**
* list_for_each_entry_safe_reverse
- * @pos: the type * to use as a loop counter.
+ * @pos: the type * to use as a loop cursor.
* @n: another type * to use as temporary storage
* @head: the head for your list.
* @member: the name of the list_struct within the struct.
/**
* list_for_each_rcu - iterate over an rcu-protected list
- * @pos: the &struct list_head to use as a loop counter.
+ * @pos: the &struct list_head to use as a loop cursor.
* @head: the head for your list.
*
* This list-traversal primitive may safely run concurrently with
/**
* list_for_each_safe_rcu
- * @pos: the &struct list_head to use as a loop counter.
+ * @pos: the &struct list_head to use as a loop cursor.
* @n: another &struct list_head to use as temporary storage
* @head: the head for your list.
*
/**
* list_for_each_entry_rcu - iterate over rcu list of given type
- * @pos: the type * to use as a loop counter.
+ * @pos: the type * to use as a loop cursor.
* @head: the head for your list.
* @member: the name of the list_struct within the struct.
*
/**
* list_for_each_continue_rcu
- * @pos: the &struct list_head to use as a loop counter.
+ * @pos: the &struct list_head to use as a loop cursor.
* @head: the head for your list.
*
* Iterate over an rcu-protected list, continuing after current point.
}
}
-/*
+/**
* 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.
+ * 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)
/**
* hlist_for_each_entry - iterate over list of given type
- * @tpos: the type * to use as a loop counter.
- * @pos: the &struct hlist_node to use as a loop counter.
+ * @tpos: the type * to use as a loop cursor.
+ * @pos: the &struct hlist_node to use as a loop cursor.
* @head: the head for your list.
* @member: the name of the hlist_node within the struct.
*/
/**
* hlist_for_each_entry_continue - iterate over a hlist continuing after current point
- * @tpos: the type * to use as a loop counter.
- * @pos: the &struct hlist_node to use as a loop counter.
+ * @tpos: the type * to use as a loop cursor.
+ * @pos: the &struct hlist_node to use as a loop cursor.
* @member: the name of the hlist_node within the struct.
*/
#define hlist_for_each_entry_continue(tpos, pos, member) \
/**
* hlist_for_each_entry_from - iterate over a hlist continuing from current point
- * @tpos: the type * to use as a loop counter.
- * @pos: the &struct hlist_node to use as a loop counter.
+ * @tpos: the type * to use as a loop cursor.
+ * @pos: the &struct hlist_node to use as a loop cursor.
* @member: the name of the hlist_node within the struct.
*/
#define hlist_for_each_entry_from(tpos, pos, member) \
/**
* hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry
- * @tpos: the type * to use as a loop counter.
- * @pos: the &struct hlist_node to use as a loop counter.
+ * @tpos: the type * to use as a loop cursor.
+ * @pos: the &struct hlist_node to use as a loop cursor.
* @n: another &struct hlist_node to use as temporary storage
* @head: the head for your list.
* @member: the name of the hlist_node within the struct.
/**
* hlist_for_each_entry_rcu - iterate over rcu list of given type
- * @tpos: the type * to use as a loop counter.
- * @pos: the &struct hlist_node to use as a loop counter.
+ * @tpos: the type * to use as a loop cursor.
+ * @pos: the &struct hlist_node to use as a loop cursor.
* @head: the head for your list.
* @member: the name of the hlist_node within the struct.
*
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