libosmocore  0.6.3
Osmocom core library
linuxlist.h
1 #ifndef _LINUX_LLIST_H
2 #define _LINUX_LLIST_H
3 
4 #include <stddef.h>
5 
6 #ifndef inline
7 #define inline __inline__
8 #endif
9 
10 static inline void prefetch(const void *x) {;}
11 
20 #define container_of(ptr, type, member) ({ \
21  const typeof( ((type *)0)->member ) *__mptr = (typeof( ((type *)0)->member ) *)(ptr); \
22  (type *)( (char *)__mptr - offsetof(type, member) );})
23 
24 
25 /*
26  * These are non-NULL pointers that will result in page faults
27  * under normal circumstances, used to verify that nobody uses
28  * non-initialized llist entries.
29  */
30 #define LLIST_POISON1 ((void *) 0x00100100)
31 #define LLIST_POISON2 ((void *) 0x00200200)
32 
33 /*
34  * Simple doubly linked llist implementation.
35  *
36  * Some of the internal functions ("__xxx") are useful when
37  * manipulating whole llists rather than single entries, as
38  * sometimes we already know the next/prev entries and we can
39  * generate better code by using them directly rather than
40  * using the generic single-entry routines.
41  */
42 
43 struct llist_head {
44  struct llist_head *next, *prev;
45 };
46 
47 #define LLIST_HEAD_INIT(name) { &(name), &(name) }
48 
49 #define LLIST_HEAD(name) \
50  struct llist_head name = LLIST_HEAD_INIT(name)
51 
52 #define INIT_LLIST_HEAD(ptr) do { \
53  (ptr)->next = (ptr); (ptr)->prev = (ptr); \
54 } while (0)
55 
56 /*
57  * Insert a new entry between two known consecutive entries.
58  *
59  * This is only for internal llist manipulation where we know
60  * the prev/next entries already!
61  */
62 static inline void __llist_add(struct llist_head *_new,
63  struct llist_head *prev,
64  struct llist_head *next)
65 {
66  next->prev = _new;
67  _new->next = next;
68  _new->prev = prev;
69  prev->next = _new;
70 }
71 
80 static inline void llist_add(struct llist_head *_new, struct llist_head *head)
81 {
82  __llist_add(_new, head, head->next);
83 }
84 
93 static inline void llist_add_tail(struct llist_head *_new, struct llist_head *head)
94 {
95  __llist_add(_new, head->prev, head);
96 }
97 
98 /*
99  * Delete a llist entry by making the prev/next entries
100  * point to each other.
101  *
102  * This is only for internal llist manipulation where we know
103  * the prev/next entries already!
104  */
105 static inline void __llist_del(struct llist_head * prev, struct llist_head * next)
106 {
107  next->prev = prev;
108  prev->next = next;
109 }
110 
117 static inline void llist_del(struct llist_head *entry)
118 {
119  __llist_del(entry->prev, entry->next);
120  entry->next = (struct llist_head *)LLIST_POISON1;
121  entry->prev = (struct llist_head *)LLIST_POISON2;
122 }
123 
128 static inline void llist_del_init(struct llist_head *entry)
129 {
130  __llist_del(entry->prev, entry->next);
131  INIT_LLIST_HEAD(entry);
132 }
133 
139 static inline void llist_move(struct llist_head *llist, struct llist_head *head)
140 {
141  __llist_del(llist->prev, llist->next);
142  llist_add(llist, head);
143 }
144 
150 static inline void llist_move_tail(struct llist_head *llist,
151  struct llist_head *head)
152 {
153  __llist_del(llist->prev, llist->next);
154  llist_add_tail(llist, head);
155 }
156 
161 static inline int llist_empty(const struct llist_head *head)
162 {
163  return head->next == head;
164 }
165 
166 static inline void __llist_splice(struct llist_head *llist,
167  struct llist_head *head)
168 {
169  struct llist_head *first = llist->next;
170  struct llist_head *last = llist->prev;
171  struct llist_head *at = head->next;
172 
173  first->prev = head;
174  head->next = first;
175 
176  last->next = at;
177  at->prev = last;
178 }
179 
185 static inline void llist_splice(struct llist_head *llist, struct llist_head *head)
186 {
187  if (!llist_empty(llist))
188  __llist_splice(llist, head);
189 }
190 
198 static inline void llist_splice_init(struct llist_head *llist,
199  struct llist_head *head)
200 {
201  if (!llist_empty(llist)) {
202  __llist_splice(llist, head);
203  INIT_LLIST_HEAD(llist);
204  }
205 }
206 
213 #define llist_entry(ptr, type, member) \
214  container_of(ptr, type, member)
215 
221 #define llist_for_each(pos, head) \
222  for (pos = (head)->next, prefetch(pos->next); pos != (head); \
223  pos = pos->next, prefetch(pos->next))
224 
235 #define __llist_for_each(pos, head) \
236  for (pos = (head)->next; pos != (head); pos = pos->next)
237 
243 #define llist_for_each_prev(pos, head) \
244  for (pos = (head)->prev, prefetch(pos->prev); pos != (head); \
245  pos = pos->prev, prefetch(pos->prev))
246 
253 #define llist_for_each_safe(pos, n, head) \
254  for (pos = (head)->next, n = pos->next; pos != (head); \
255  pos = n, n = pos->next)
256 
263 #define llist_for_each_entry(pos, head, member) \
264  for (pos = llist_entry((head)->next, typeof(*pos), member), \
265  prefetch(pos->member.next); \
266  &pos->member != (head); \
267  pos = llist_entry(pos->member.next, typeof(*pos), member), \
268  prefetch(pos->member.next))
269 
276 #define llist_for_each_entry_reverse(pos, head, member) \
277  for (pos = llist_entry((head)->prev, typeof(*pos), member), \
278  prefetch(pos->member.prev); \
279  &pos->member != (head); \
280  pos = llist_entry(pos->member.prev, typeof(*pos), member), \
281  prefetch(pos->member.prev))
282 
290 #define llist_for_each_entry_continue(pos, head, member) \
291  for (pos = llist_entry(pos->member.next, typeof(*pos), member), \
292  prefetch(pos->member.next); \
293  &pos->member != (head); \
294  pos = llist_entry(pos->member.next, typeof(*pos), member), \
295  prefetch(pos->member.next))
296 
304 #define llist_for_each_entry_safe(pos, n, head, member) \
305  for (pos = llist_entry((head)->next, typeof(*pos), member), \
306  n = llist_entry(pos->member.next, typeof(*pos), member); \
307  &pos->member != (head); \
308  pos = n, n = llist_entry(n->member.next, typeof(*n), member))
309 
315 #define llist_for_each_rcu(pos, head) \
316  for (pos = (head)->next, prefetch(pos->next); pos != (head); \
317  pos = pos->next, ({ smp_read_barrier_depends(); 0;}), prefetch(pos->next))
318 
319 #define __llist_for_each_rcu(pos, head) \
320  for (pos = (head)->next; pos != (head); \
321  pos = pos->next, ({ smp_read_barrier_depends(); 0;}))
322 
330 #define llist_for_each_safe_rcu(pos, n, head) \
331  for (pos = (head)->next, n = pos->next; pos != (head); \
332  pos = n, ({ smp_read_barrier_depends(); 0;}), n = pos->next)
333 
340 #define llist_for_each_entry_rcu(pos, head, member) \
341  for (pos = llist_entry((head)->next, typeof(*pos), member), \
342  prefetch(pos->member.next); \
343  &pos->member != (head); \
344  pos = llist_entry(pos->member.next, typeof(*pos), member), \
345  ({ smp_read_barrier_depends(); 0;}), \
346  prefetch(pos->member.next))
347 
348 
355 #define llist_for_each_continue_rcu(pos, head) \
356  for ((pos) = (pos)->next, prefetch((pos)->next); (pos) != (head); \
357  (pos) = (pos)->next, ({ smp_read_barrier_depends(); 0;}), prefetch((pos)->next))
358 
359 
360 #endif