linux/net/rds/xlist.h

81 lines
1.4 KiB
C

#ifndef _LINUX_XLIST_H
#define _LINUX_XLIST_H
#include <linux/stddef.h>
#include <linux/poison.h>
#include <linux/prefetch.h>
#include <asm/system.h>
struct xlist_head {
struct xlist_head *next;
};
static inline void INIT_XLIST_HEAD(struct xlist_head *list)
{
list->next = NULL;
}
static inline int xlist_empty(struct xlist_head *head)
{
return head->next == NULL;
}
static inline void xlist_add(struct xlist_head *new, struct xlist_head *tail,
struct xlist_head *head)
{
struct xlist_head *cur;
struct xlist_head *check;
while (1) {
cur = head->next;
tail->next = cur;
check = cmpxchg(&head->next, cur, new);
if (check == cur)
break;
}
}
static inline struct xlist_head *xlist_del_head(struct xlist_head *head)
{
struct xlist_head *cur;
struct xlist_head *check;
struct xlist_head *next;
while (1) {
cur = head->next;
if (!cur)
goto out;
next = cur->next;
check = cmpxchg(&head->next, cur, next);
if (check == cur)
goto out;
}
out:
return cur;
}
static inline struct xlist_head *xlist_del_head_fast(struct xlist_head *head)
{
struct xlist_head *cur;
cur = head->next;
if (!cur)
return NULL;
head->next = cur->next;
return cur;
}
static inline void xlist_splice(struct xlist_head *list,
struct xlist_head *head)
{
struct xlist_head *cur;
WARN_ON(head->next);
cur = xchg(&list->next, NULL);
head->next = cur;
}
#endif