Revert "genirq: Add fasteoi IPI flow"

handle_percpu_devid_fasteoi_ipi() has no more users, and
handle_percpu_devid_irq() can do all that it was supposed to do. Get rid of
it.

This reverts commit c5e5ec03.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201109094121.29975-6-valentin.schneider@arm.com

include/linux/irq.h

@@ -647,7 +647,6 @@ static inline int irq_set_parent(int irq, int parent_irq)
  */
 extern void handle_level_irq(struct irq_desc *desc);
 extern void handle_fasteoi_irq(struct irq_desc *desc);
-extern void handle_percpu_devid_fasteoi_ipi(struct irq_desc *desc);
 extern void handle_edge_irq(struct irq_desc *desc);
 extern void handle_edge_eoi_irq(struct irq_desc *desc);
 extern void handle_simple_irq(struct irq_desc *desc);

kernel/irq/chip.c

@@ -944,33 +944,6 @@ void handle_percpu_devid_irq(struct irq_desc *desc)
 		chip->irq_eoi(&desc->irq_data);
 }
 
-/**
- * handle_percpu_devid_fasteoi_ipi - Per CPU local IPI handler with per cpu
- *				     dev ids
- * @desc:	the interrupt description structure for this irq
- *
- * The biggest difference with the IRQ version is that the interrupt is
- * EOIed early, as the IPI could result in a context switch, and we need to
- * make sure the IPI can fire again. We also assume that the arch code has
- * registered an action. If not, we are positively doomed.
- */
-void handle_percpu_devid_fasteoi_ipi(struct irq_desc *desc)
-{
-	struct irq_chip *chip = irq_desc_get_chip(desc);
-	struct irqaction *action = desc->action;
-	unsigned int irq = irq_desc_get_irq(desc);
-	irqreturn_t res;
-
-	__kstat_incr_irqs_this_cpu(desc);
-
-	if (chip->irq_eoi)
-		chip->irq_eoi(&desc->irq_data);
-
-	trace_irq_handler_entry(irq, action);
-	res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id));
-	trace_irq_handler_exit(irq, action, res);
-}
-
 /**
  * handle_percpu_devid_fasteoi_nmi - Per CPU local NMI handler with per cpu
  *				     dev ids