From: Ingo Molnar <mingo@elte.hu>

Clean up the fastack concept by turning it into fasteoi and introducing the
->eoi() method for chips.

This also allows the cleanup of an i386 EOI quirk - now the quirk is
cleanly separated from the pure ACK implementation.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 include/linux/irq.h |    6 ++++--
 kernel/irq/chip.c   |   25 ++++++++++++-------------
 2 files changed, 16 insertions(+), 15 deletions(-)

diff -puN include/linux/irq.h~genirq-add-chip-eoi-fastack-fasteoi-core include/linux/irq.h
--- a/include/linux/irq.h~genirq-add-chip-eoi-fastack-fasteoi-core
+++ a/include/linux/irq.h
@@ -74,7 +74,8 @@ struct proc_dir_entry;
  * @mask:		mask an interrupt source
  * @mask_ack:		ack and mask an interrupt source
  * @unmask:		unmask an interrupt source
- * @end:		end of interrupt
+ * @eoi:		end of interrupt - chip level
+ * @end:		end of interrupt - flow level
  * @set_affinity:	set the CPU affinity on SMP machines
  * @retrigger:		resend an IRQ to the CPU
  * @set_type:		set the flow type (IRQ_TYPE_LEVEL/etc.) of an IRQ
@@ -94,6 +95,7 @@ struct irq_chip {
 	void		(*mask)(unsigned int irq);
 	void		(*mask_ack)(unsigned int irq);
 	void		(*unmask)(unsigned int irq);
+	void		(*eoi)(unsigned int irq);
 
 	void		(*end)(unsigned int irq);
 	void		(*set_affinity)(unsigned int irq, cpumask_t dest);
@@ -288,7 +290,7 @@ extern int handle_IRQ_event(unsigned int
 extern void fastcall
 handle_level_irq(unsigned int irq, struct irq_desc *desc, struct pt_regs *regs);
 extern void fastcall
-handle_fastack_irq(unsigned int irq, struct irq_desc *desc,
+handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc,
 			 struct pt_regs *regs);
 extern void fastcall
 handle_edge_irq(unsigned int irq, struct irq_desc *desc, struct pt_regs *regs);
diff -puN kernel/irq/chip.c~genirq-add-chip-eoi-fastack-fasteoi-core kernel/irq/chip.c
--- a/kernel/irq/chip.c~genirq-add-chip-eoi-fastack-fasteoi-core
+++ a/kernel/irq/chip.c
@@ -280,18 +280,18 @@ out:
 }
 
 /**
- *	handle_fastack_irq - irq handler for transparent controllers
+ *	handle_fasteoi_irq - irq handler for transparent controllers
  *	@irq:	the interrupt number
  *	@desc:	the interrupt description structure for this irq
  *	@regs:	pointer to a register structure
  *
- *	Only a single callback will be issued to the chip: an ->ack()
+ *	Only a single callback will be issued to the chip: an ->eoi()
  *	call when the interrupt has been serviced. This enables support
  *	for modern forms of interrupt handlers, which handle the flow
  *	details in hardware, transparently.
  */
 void fastcall
-handle_fastack_irq(unsigned int irq, struct irq_desc *desc,
+handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc,
 		   struct pt_regs *regs)
 {
 	unsigned int cpu = smp_processor_id();
@@ -327,10 +327,9 @@ handle_fastack_irq(unsigned int irq, str
 	spin_lock(&desc->lock);
 	desc->status &= ~IRQ_INPROGRESS;
 out:
-	if (!(desc->status & IRQ_DISABLED))
-		desc->chip->ack(irq);
-	else
+	if (unlikely(desc->status & IRQ_DISABLED))
 		desc->chip->mask(irq);
+	desc->chip->eoi(irq);
 
 	spin_unlock(&desc->lock);
 }
@@ -510,19 +509,19 @@ handle_irq_name(void fastcall (*handle)(
 					struct pt_regs *))
 {
 	if (handle == handle_level_irq)
-		return "level ";
-	if (handle == handle_fastack_irq)
-		return "level ";
+		return "level  ";
+	if (handle == handle_fasteoi_irq)
+		return "fasteoi";
 	if (handle == handle_edge_irq)
-		return "edge  ";
+		return "edge   ";
 	if (handle == handle_simple_irq)
-		return "simple";
+		return "simple ";
 #ifdef CONFIG_SMP
 	if (handle == handle_percpu_irq)
-		return "percpu";
+		return "percpu ";
 #endif
 	if (handle == handle_bad_irq)
-		return "bad   ";
+		return "bad    ";
 
 	return NULL;
 }
_