Commit a1b09501 authored by Mark Rutland's avatar Mark Rutland
Browse files

irq: add generic_handle_arch_irq() 



Several architectures select GENERIC_IRQ_MULTI_HANDLER and branch to
handle_arch_irq() without performing any entry accounting.

Add a generic wrapper to handle the common irqentry work when invoking
handle_arch_irq(). Where an architecture needs to perform some entry
accounting itself, it will need to invoke handle_arch_irq() itself.

In subsequent patches it will become the responsibilty of the entry code
to set the irq regs when entering an IRQ (rather than deferring this to
an irqchip handler), so generic_handle_arch_irq() is made to set the irq
regs now. This can be redundant in some cases, but is never harmful as
saving/restoring the old regs nests safely.

Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
Reviewed-by: default avatarMarc Zyngier <maz@kernel.org>
Reviewed-by: default avatarGuo Ren <guoren@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
parent 76adc5be

include/linux/irq.h

+1 −0
Original line number Diff line number Diff line
@@ -1261,6 +1261,7 @@ int __init set_handle_irq(void (*handle_irq)(struct pt_regs *)); 
 * top-level IRQ handler.

 */

extern void (*handle_arch_irq)(struct pt_regs *) __ro_after_init;

asmlinkage void generic_handle_arch_irq(struct pt_regs *regs);

#else

#ifndef set_handle_irq

#define set_handle_irq(handle_irq)		\

kernel/irq/handle.c

+18 −0
Original line number Diff line number Diff line
@@ -14,6 +14,8 @@ 
#include <linux/interrupt.h>

#include <linux/kernel_stat.h>



#include <asm/irq_regs.h>



#include <trace/events/irq.h>



#include "internals.h"
@@ -226,4 +228,20 @@ int __init set_handle_irq(void (*handle_irq)(struct pt_regs *)) 
	handle_arch_irq = handle_irq;

	return 0;

}



/**

 * generic_handle_arch_irq - root irq handler for architectures which do no

 *                           entry accounting themselves

 * @regs:	Register file coming from the low-level handling code

 */

asmlinkage void noinstr generic_handle_arch_irq(struct pt_regs *regs)

{

	struct pt_regs *old_regs;



	irq_enter();

	old_regs = set_irq_regs(regs);

	handle_arch_irq(regs);

	set_irq_regs(old_regs);

	irq_exit();

}

#endif