x86: Simplify timer_ack magic in time_32.c

Let the compiler optimize the timer_ack magic away in the 32bit timer
interrupt and put the same code into time_64.c. It's optimized out for
CONFIG_X86_IO_APIC on 32bit and for 64bit because timer_ack is const 0
in both cases.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 3 insertions, 2 deletions

diff --git a/arch/x86/kernel/time_32.c b/arch/x86/kernel/time_32.c
index acbaefd61e8e..7a26bcf887f6 100644
--- a/arch/x86/kernel/time_32.c
+++ b/arch/x86/kernel/time_32.c
@@ -23,7 +23,9 @@
 #include <asm/time.h>
 #include <asm/nmi.h>
 
+#if defined(CONFIG_X86_32) && defined(CONFIG_X86_IO_APIC)
 int timer_ack;
+#endif
 
 unsigned long profile_pc(struct pt_regs *regs)
 {
@@ -60,7 +62,7 @@ static irqreturn_t timer_interrupt(int irq, void *dev_id)
         /* Keep nmi watchdog up to date */
         inc_irq_stat(irq0_irqs);
 
-#ifdef CONFIG_X86_IO_APIC
+        /* Optimized out for !IO_APIC and x86_64 */
         if (timer_ack) {
                 /*
                  * Subtle, when I/O APICs are used we have to ack timer IRQ
@@ -73,7 +75,6 @@ static irqreturn_t timer_interrupt(int irq, void *dev_id)
                 inb(PIC_MASTER_POLL);
                 spin_unlock(&i8259A_lock);
         }
-#endif
 
         global_clock_event->event_handler(global_clock_event);