mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git
synced 2026-11-12 04:22:27 +01:00
Peter Zijlstra
02cea39586
For things like netpoll there is a need to disable an interrupt from atomic context. Currently netpoll uses disable_irq() which will sleep-wait on threaded handlers and thus forced_irqthreads breaks things. Provide disable_hardirq(), which uses synchronize_hardirq() to only wait for active hardirq handlers; also change synchronize_hardirq() to return the status of threaded handlers. This will allow one to try-disable an interrupt from atomic context, or in case of request_threaded_irq() to only wait for the hardirq part. Suggested-by: Sabrina Dubroca <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: David Miller <[email protected]> Cc: Eyal Perry <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Quentin Lambert <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Russell King <[email protected]> Link: http://lkml.kernel.org/r/[email protected] [ Fixed typos and such. ] Signed-off-by: Ingo Molnar <[email protected]>
83 lines
1.7 KiB
C
83 lines
1.7 KiB
C
#ifndef LINUX_HARDIRQ_H
|
|
#define LINUX_HARDIRQ_H
|
|
|
|
#include <linux/preempt_mask.h>
|
|
#include <linux/lockdep.h>
|
|
#include <linux/ftrace_irq.h>
|
|
#include <linux/vtime.h>
|
|
#include <asm/hardirq.h>
|
|
|
|
|
|
extern void synchronize_irq(unsigned int irq);
|
|
extern bool synchronize_hardirq(unsigned int irq);
|
|
|
|
#if defined(CONFIG_TINY_RCU)
|
|
|
|
static inline void rcu_nmi_enter(void)
|
|
{
|
|
}
|
|
|
|
static inline void rcu_nmi_exit(void)
|
|
{
|
|
}
|
|
|
|
#else
|
|
extern void rcu_nmi_enter(void);
|
|
extern void rcu_nmi_exit(void);
|
|
#endif
|
|
|
|
/*
|
|
* It is safe to do non-atomic ops on ->hardirq_context,
|
|
* because NMI handlers may not preempt and the ops are
|
|
* always balanced, so the interrupted value of ->hardirq_context
|
|
* will always be restored.
|
|
*/
|
|
#define __irq_enter() \
|
|
do { \
|
|
account_irq_enter_time(current); \
|
|
preempt_count_add(HARDIRQ_OFFSET); \
|
|
trace_hardirq_enter(); \
|
|
} while (0)
|
|
|
|
/*
|
|
* Enter irq context (on NO_HZ, update jiffies):
|
|
*/
|
|
extern void irq_enter(void);
|
|
|
|
/*
|
|
* Exit irq context without processing softirqs:
|
|
*/
|
|
#define __irq_exit() \
|
|
do { \
|
|
trace_hardirq_exit(); \
|
|
account_irq_exit_time(current); \
|
|
preempt_count_sub(HARDIRQ_OFFSET); \
|
|
} while (0)
|
|
|
|
/*
|
|
* Exit irq context and process softirqs if needed:
|
|
*/
|
|
extern void irq_exit(void);
|
|
|
|
#define nmi_enter() \
|
|
do { \
|
|
lockdep_off(); \
|
|
ftrace_nmi_enter(); \
|
|
BUG_ON(in_nmi()); \
|
|
preempt_count_add(NMI_OFFSET + HARDIRQ_OFFSET); \
|
|
rcu_nmi_enter(); \
|
|
trace_hardirq_enter(); \
|
|
} while (0)
|
|
|
|
#define nmi_exit() \
|
|
do { \
|
|
trace_hardirq_exit(); \
|
|
rcu_nmi_exit(); \
|
|
BUG_ON(!in_nmi()); \
|
|
preempt_count_sub(NMI_OFFSET + HARDIRQ_OFFSET); \
|
|
ftrace_nmi_exit(); \
|
|
lockdep_on(); \
|
|
} while (0)
|
|
|
|
#endif /* LINUX_HARDIRQ_H */
|