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: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Guo Ren <guoren@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Mark Rutland 2021-10-20 11:24:06 +01:00
parent 76adc5be6f
commit a1b0950197
2 changed files with 19 additions and 0 deletions

View File

@ -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) \

View File

@ -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