xref: /openbmc/linux/include/linux/timerqueue.h (revision 2f117484) 
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_TIMERQUEUE_H
3 #define _LINUX_TIMERQUEUE_H
4 
5 #include <linux/rbtree.h>
6 #include <linux/ktime.h>
7 
8 
9 struct timerqueue_node {
10 	struct rb_node node;
11 	ktime_t expires;
12 };
13 
14 struct timerqueue_head {
15 	struct rb_root_cached rb_root;
16 };
17 
18 
19 extern bool timerqueue_add(struct timerqueue_head *head,
20 			   struct timerqueue_node *node);
21 extern bool timerqueue_del(struct timerqueue_head *head,
22 			   struct timerqueue_node *node);
23 extern struct timerqueue_node *timerqueue_iterate_next(
24 						struct timerqueue_node *node);
25 
26 /**
27  * timerqueue_getnext - Returns the timer with the earliest expiration time
28  *
29  * @head: head of timerqueue
30  *
31  * Returns a pointer to the timer node that has the earliest expiration time.
32  */
33 static inline
timerqueue_getnext(struct timerqueue_head * head)34 struct timerqueue_node *timerqueue_getnext(struct timerqueue_head *head)
35 {
36 	struct rb_node *leftmost = rb_first_cached(&head->rb_root);
37 
38 	return rb_entry_safe(leftmost, struct timerqueue_node, node);
39 }
40 
timerqueue_init(struct timerqueue_node * node)41 static inline void timerqueue_init(struct timerqueue_node *node)
42 {
43 	RB_CLEAR_NODE(&node->node);
44 }
45 
timerqueue_node_queued(struct timerqueue_node * node)46 static inline bool timerqueue_node_queued(struct timerqueue_node *node)
47 {
48 	return !RB_EMPTY_NODE(&node->node);
49 }
50 
timerqueue_node_expires(struct timerqueue_node * node)51 static inline bool timerqueue_node_expires(struct timerqueue_node *node)
52 {
53 	return node->expires;
54 }
55 
timerqueue_init_head(struct timerqueue_head * head)56 static inline void timerqueue_init_head(struct timerqueue_head *head)
57 {
58 	head->rb_root = RB_ROOT_CACHED;
59 }
60 #endif /* _LINUX_TIMERQUEUE_H */
61