Commit | Line | Data |
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6fa70da6 CM |
1 | #ifndef _LINUX_XLIST_H |
2 | #define _LINUX_XLIST_H | |
3 | ||
4 | #include <linux/stddef.h> | |
5 | #include <linux/poison.h> | |
6 | #include <linux/prefetch.h> | |
7 | #include <asm/system.h> | |
8 | ||
9 | struct xlist_head { | |
10 | struct xlist_head *next; | |
11 | }; | |
12 | ||
fbf4d7e3 AG |
13 | static inline void INIT_XLIST_HEAD(struct xlist_head *list) |
14 | { | |
15 | list->next = NULL; | |
16 | } | |
17 | ||
18 | static inline int xlist_empty(struct xlist_head *head) | |
19 | { | |
20 | return head->next == NULL; | |
21 | } | |
6fa70da6 | 22 | |
fbf4d7e3 AG |
23 | static inline void xlist_add(struct xlist_head *new, struct xlist_head *tail, |
24 | struct xlist_head *head) | |
6fa70da6 CM |
25 | { |
26 | struct xlist_head *cur; | |
27 | struct xlist_head *check; | |
28 | ||
29 | while (1) { | |
30 | cur = head->next; | |
31 | tail->next = cur; | |
32 | check = cmpxchg(&head->next, cur, new); | |
33 | if (check == cur) | |
34 | break; | |
35 | } | |
36 | } | |
37 | ||
6fa70da6 CM |
38 | static inline struct xlist_head *xlist_del_head(struct xlist_head *head) |
39 | { | |
40 | struct xlist_head *cur; | |
41 | struct xlist_head *check; | |
42 | struct xlist_head *next; | |
43 | ||
44 | while (1) { | |
45 | cur = head->next; | |
46 | if (!cur) | |
47 | goto out; | |
48 | ||
6fa70da6 CM |
49 | next = cur->next; |
50 | check = cmpxchg(&head->next, cur, next); | |
51 | if (check == cur) | |
52 | goto out; | |
53 | } | |
54 | out: | |
55 | return cur; | |
56 | } | |
57 | ||
58 | static inline struct xlist_head *xlist_del_head_fast(struct xlist_head *head) | |
59 | { | |
60 | struct xlist_head *cur; | |
61 | ||
62 | cur = head->next; | |
fbf4d7e3 | 63 | if (!cur) |
6fa70da6 CM |
64 | return NULL; |
65 | ||
66 | head->next = cur->next; | |
67 | return cur; | |
68 | } | |
69 | ||
70 | static inline void xlist_splice(struct xlist_head *list, | |
71 | struct xlist_head *head) | |
72 | { | |
73 | struct xlist_head *cur; | |
74 | ||
75 | WARN_ON(head->next); | |
76 | cur = xchg(&list->next, NULL); | |
77 | head->next = cur; | |
78 | } | |
79 | ||
6fa70da6 | 80 | #endif |