While SPIs are shared between CPU, it is not possible to receive the
same interrupts on a different CPU while the interrupt is in active
state. The deactivation of the interrupt is done at the end of the
handling.
This means the _IRQ_PENDING logic is unecessary on Arm as a same
interrupt can never come up while in the loop. So remove it to
simplify the interrupt handle code.
Signed-off-by: Julien Grall <julien.grall@xxxxxxx>
---
xen/arch/arm/irq.c | 32 ++++++++++----------------------
1 file changed, 10 insertions(+), 22 deletions(-)
diff --git a/xen/arch/arm/irq.c b/xen/arch/arm/irq.c
index c51cf333ce..3877657a52 100644
--- a/xen/arch/arm/irq.c
+++ b/xen/arch/arm/irq.c
@@ -199,6 +199,7 @@ int request_irq(unsigned int irq, unsigned int irqflags,
void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq)
{
struct irq_desc *desc = irq_to_desc(irq);
+ struct irqaction *action;
perfc_incr(irqs);
@@ -242,35 +243,22 @@ void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq)
goto out_no_end;
}
- set_bit(_IRQ_PENDING, &desc->status);
-
- /*
- * Since we set PENDING, if another processor is handling a different
- * instance of this same irq, the other processor will take care of it.
- */
- if ( test_bit(_IRQ_DISABLED, &desc->status) ||
- test_bit(_IRQ_INPROGRESS, &desc->status) )
+ if ( test_bit(_IRQ_DISABLED, &desc->status) )
goto out;
set_bit(_IRQ_INPROGRESS, &desc->status);
- while ( test_bit(_IRQ_PENDING, &desc->status) )
- {
- struct irqaction *action;
+ action = desc->action;
- clear_bit(_IRQ_PENDING, &desc->status);
- action = desc->action;
+ spin_unlock_irq(&desc->lock);
- spin_unlock_irq(&desc->lock);
-
- do
- {
- action->handler(irq, action->dev_id, regs);
- action = action->next;
- } while ( action );
+ do
+ {
+ action->handler(irq, action->dev_id, regs);
+ action = action->next;
+ } while ( action );
- spin_lock_irq(&desc->lock);
- }
+ spin_lock_irq(&desc->lock);
clear_bit(_IRQ_INPROGRESS, &desc->status);
