linux-stable/include/linux/irq_work.h
Sebastian Andrzej Siewior 49915ac35c lockdep: Annotate irq_work
Mark irq_work items with IRQ_WORK_HARD_IRQ which should be invoked in
hardirq context even on PREEMPT_RT. IRQ_WORK without this flag will be
invoked in softirq context on PREEMPT_RT.

Set ->irq_config to 1 for the IRQ_WORK items which are invoked in softirq
context so lockdep knows that these can safely acquire a spinlock_t.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.643576700@linutronix.de
2020-03-21 16:00:24 +01:00

61 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_IRQ_WORK_H
#define _LINUX_IRQ_WORK_H
#include <linux/llist.h>
/*
* An entry can be in one of four states:
*
* free NULL, 0 -> {claimed} : free to be used
* claimed NULL, 3 -> {pending} : claimed to be enqueued
* pending next, 3 -> {busy} : queued, pending callback
* busy NULL, 2 -> {free, claimed} : callback in progress, can be claimed
*/
#define IRQ_WORK_PENDING BIT(0)
#define IRQ_WORK_BUSY BIT(1)
/* Doesn't want IPI, wait for tick: */
#define IRQ_WORK_LAZY BIT(2)
/* Run hard IRQ context, even on RT */
#define IRQ_WORK_HARD_IRQ BIT(3)
#define IRQ_WORK_CLAIMED (IRQ_WORK_PENDING | IRQ_WORK_BUSY)
struct irq_work {
atomic_t flags;
struct llist_node llnode;
void (*func)(struct irq_work *);
};
static inline
void init_irq_work(struct irq_work *work, void (*func)(struct irq_work *))
{
atomic_set(&work->flags, 0);
work->func = func;
}
#define DEFINE_IRQ_WORK(name, _f) struct irq_work name = { \
.flags = ATOMIC_INIT(0), \
.func = (_f) \
}
bool irq_work_queue(struct irq_work *work);
bool irq_work_queue_on(struct irq_work *work, int cpu);
void irq_work_tick(void);
void irq_work_sync(struct irq_work *work);
#ifdef CONFIG_IRQ_WORK
#include <asm/irq_work.h>
void irq_work_run(void);
bool irq_work_needs_cpu(void);
#else
static inline bool irq_work_needs_cpu(void) { return false; }
static inline void irq_work_run(void) { }
#endif
#endif /* _LINUX_IRQ_WORK_H */