xref: /openbmc/linux/include/linux/irq_work.h (revision 68198dca)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_IRQ_WORK_H
3 #define _LINUX_IRQ_WORK_H
4 
5 #include <linux/llist.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 #define IRQ_WORK_PENDING	1UL
17 #define IRQ_WORK_BUSY		2UL
18 #define IRQ_WORK_FLAGS		3UL
19 #define IRQ_WORK_LAZY		4UL /* Doesn't want IPI, wait for tick */
20 
21 struct irq_work {
22 	unsigned long flags;
23 	struct llist_node llnode;
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 	work->flags = 0;
31 	work->func = func;
32 }
33 
34 #define DEFINE_IRQ_WORK(name, _f) struct irq_work name = { .func = (_f), }
35 
36 bool irq_work_queue(struct irq_work *work);
37 bool irq_work_queue_on(struct irq_work *work, int cpu);
38 
39 void irq_work_tick(void);
40 void irq_work_sync(struct irq_work *work);
41 
42 #ifdef CONFIG_IRQ_WORK
43 #include <asm/irq_work.h>
44 
45 void irq_work_run(void);
46 bool irq_work_needs_cpu(void);
47 #else
48 static inline bool irq_work_needs_cpu(void) { return false; }
49 static inline void irq_work_run(void) { }
50 #endif
51 
52 #endif /* _LINUX_IRQ_WORK_H */
53