genirq: Provide irq_enter/exit_rcu()

irq_enter()/exit() currently include RCU handling. To properly separate the RCU
handling code, provide variants which contain only the non-RCU related
functionality.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20200521202117.567023613@linutronix.de
This commit is contained in:
Thomas Gleixner 2020-05-21 22:05:21 +02:00
parent 9ee01e0f69
commit 8a6bc4787f
2 changed files with 38 additions and 10 deletions

View File

@ -40,7 +40,11 @@ static __always_inline void rcu_irq_enter_check_tick(void)
/*
* Enter irq context (on NO_HZ, update jiffies):
*/
extern void irq_enter(void);
void irq_enter(void);
/*
* Like irq_enter(), but RCU is already watching.
*/
void irq_enter_rcu(void);
/*
* Exit irq context without processing softirqs:
@ -55,7 +59,12 @@ extern void irq_enter(void);
/*
* Exit irq context and process softirqs if needed:
*/
extern void irq_exit(void);
void irq_exit(void);
/*
* Like irq_exit(), but return with RCU watching.
*/
void irq_exit_rcu(void);
#ifndef arch_nmi_enter
#define arch_nmi_enter() do { } while (0)

View File

@ -339,12 +339,11 @@ asmlinkage __visible void do_softirq(void)
local_irq_restore(flags);
}
/*
* Enter an interrupt context.
/**
* irq_enter_rcu - Enter an interrupt context with RCU watching
*/
void irq_enter(void)
void irq_enter_rcu(void)
{
rcu_irq_enter();
if (is_idle_task(current) && !in_interrupt()) {
/*
* Prevent raise_softirq from needlessly waking up ksoftirqd
@ -354,10 +353,18 @@ void irq_enter(void)
tick_irq_enter();
_local_bh_enable();
}
__irq_enter();
}
/**
* irq_enter - Enter an interrupt context including RCU update
*/
void irq_enter(void)
{
rcu_irq_enter();
irq_enter_rcu();
}
static inline void invoke_softirq(void)
{
if (ksoftirqd_running(local_softirq_pending()))
@ -397,10 +404,12 @@ static inline void tick_irq_exit(void)
#endif
}
/*
* Exit an interrupt context. Process softirqs if needed and possible:
/**
* irq_exit_rcu() - Exit an interrupt context without updating RCU
*
* Also processes softirqs if needed and possible.
*/
void irq_exit(void)
void irq_exit_rcu(void)
{
#ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED
local_irq_disable();
@ -413,6 +422,16 @@ void irq_exit(void)
invoke_softirq();
tick_irq_exit();
}
/**
* irq_exit - Exit an interrupt context, update RCU and lockdep
*
* Also processes softirqs if needed and possible.
*/
void irq_exit(void)
{
irq_exit_rcu();
rcu_irq_exit();
/* must be last! */
lockdep_hardirq_exit();