include/linux/irq_work.h

   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 /* flags share CSD_FLAG_ space */
  17
  18 #define IRQ_WORK_PENDING        BIT(0)
  19 #define IRQ_WORK_BUSY           BIT(1)
  20
  21 /* Doesn't want IPI, wait for tick: */
  22 #define IRQ_WORK_LAZY           BIT(2)
  23 /* Run hard IRQ context, even on RT */
  24 #define IRQ_WORK_HARD_IRQ       BIT(3)
  25
  26 #define IRQ_WORK_CLAIMED        (IRQ_WORK_PENDING | IRQ_WORK_BUSY)
  27
  28 /*
  29  * structure shares layout with single_call_data_t.
  30  */
  31 struct irq_work {
  32         struct llist_node llnode;
  33         atomic_t flags;
  34         void (*func)(struct irq_work *);
  35 };
  36
  37 static inline
  38 void init_irq_work(struct irq_work *work, void (*func)(struct irq_work *))
  39 {
  40         atomic_set(&work->flags, 0);
  41         work->func = func;
  42 }
  43
  44 #define DEFINE_IRQ_WORK(name, _f) struct irq_work name = {      \
  45                 .flags = ATOMIC_INIT(0),                        \
  46                 .func  = (_f)                                   \
  47 }
  48
  49
  50 bool irq_work_queue(struct irq_work *work);
  51 bool irq_work_queue_on(struct irq_work *work, int cpu);
  52
  53 void irq_work_tick(void);
  54 void irq_work_sync(struct irq_work *work);
  55
  56 #ifdef CONFIG_IRQ_WORK
  57 #include <asm/irq_work.h>
  58
  59 void irq_work_run(void);
  60 bool irq_work_needs_cpu(void);
  61 void irq_work_single(void *arg);
  62 #else
  63 static inline bool irq_work_needs_cpu(void) { return false; }
  64 static inline void irq_work_run(void) { }
  65 static inline void irq_work_single(void *arg) { }
  66 #endif
  67
  68 #endif /* _LINUX_IRQ_WORK_H */