xref: /openbmc/linux/include/linux/irq_work.h (revision b03afaa8)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_IRQ_WORK_H
3 #define _LINUX_IRQ_WORK_H
4 
5 #include <linux/smp_types.h>
6 
7 /*
8  * An entry can be in one of four states:
9  *
10  * free	     NULL, 0 -> {claimed}       : free to be used
11  * claimed   NULL, 3 -> {pending}       : claimed to be enqueued
12  * pending   next, 3 -> {busy}          : queued, pending callback
13  * busy      NULL, 2 -> {free, claimed} : callback in progress, can be claimed
14  */
15 
16 struct irq_work {
17 	union {
18 		struct __call_single_node node;
19 		struct {
20 			struct llist_node llnode;
21 			atomic_t flags;
22 		};
23 	};
24 	void (*func)(struct irq_work *);
25 };
26 
27 static inline
28 void init_irq_work(struct irq_work *work, void (*func)(struct irq_work *))
29 {
30 	atomic_set(&work->flags, 0);
31 	work->func = func;
32 }
33 
34 #define DEFINE_IRQ_WORK(name, _f) struct irq_work name = {	\
35 		.flags = ATOMIC_INIT(0),			\
36 		.func  = (_f)					\
37 }
38 
39 
40 bool irq_work_queue(struct irq_work *work);
41 bool irq_work_queue_on(struct irq_work *work, int cpu);
42 
43 void irq_work_tick(void);
44 void irq_work_sync(struct irq_work *work);
45 
46 #ifdef CONFIG_IRQ_WORK
47 #include <asm/irq_work.h>
48 
49 void irq_work_run(void);
50 bool irq_work_needs_cpu(void);
51 void irq_work_single(void *arg);
52 #else
53 static inline bool irq_work_needs_cpu(void) { return false; }
54 static inline void irq_work_run(void) { }
55 static inline void irq_work_single(void *arg) { }
56 #endif
57 
58 #endif /* _LINUX_IRQ_WORK_H */
59