xref: /openbmc/linux/include/linux/irq_work.h (revision 9cfc5c90)
1 #ifndef _LINUX_IRQ_WORK_H
2 #define _LINUX_IRQ_WORK_H
3 
4 #include <linux/llist.h>
5 
6 /*
7  * An entry can be in one of four states:
8  *
9  * free	     NULL, 0 -> {claimed}       : free to be used
10  * claimed   NULL, 3 -> {pending}       : claimed to be enqueued
11  * pending   next, 3 -> {busy}          : queued, pending callback
12  * busy      NULL, 2 -> {free, claimed} : callback in progress, can be claimed
13  */
14 
15 #define IRQ_WORK_PENDING	1UL
16 #define IRQ_WORK_BUSY		2UL
17 #define IRQ_WORK_FLAGS		3UL
18 #define IRQ_WORK_LAZY		4UL /* Doesn't want IPI, wait for tick */
19 
20 struct irq_work {
21 	unsigned long flags;
22 	struct llist_node llnode;
23 	void (*func)(struct irq_work *);
24 };
25 
26 static inline
27 void init_irq_work(struct irq_work *work, void (*func)(struct irq_work *))
28 {
29 	work->flags = 0;
30 	work->func = func;
31 }
32 
33 #define DEFINE_IRQ_WORK(name, _f) struct irq_work name = { .func = (_f), }
34 
35 bool irq_work_queue(struct irq_work *work);
36 
37 #ifdef CONFIG_SMP
38 bool irq_work_queue_on(struct irq_work *work, int cpu);
39 #endif
40 
41 void irq_work_tick(void);
42 void irq_work_sync(struct irq_work *work);
43 
44 #ifdef CONFIG_IRQ_WORK
45 #include <asm/irq_work.h>
46 
47 void irq_work_run(void);
48 bool irq_work_needs_cpu(void);
49 #else
50 static inline bool irq_work_needs_cpu(void) { return false; }
51 static inline void irq_work_run(void) { }
52 #endif
53 
54 #endif /* _LINUX_IRQ_WORK_H */
55