From: Ralf Baechle <ralf@linux-mips.org>
Date: Wed, 30 Jan 2008 12:30:47 +0000 (+0100)
Subject: mips, x86: optimize the i8259 code a bit
X-Git-Tag: v2.6.25-rc1~1143^2~714
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5f627f8e122a163ce53908d55e088247db31f1d7;p=linux-2.6

mips, x86: optimize the i8259 code a bit

The timer code always calls the clock_event_device set_net_event and
set_mode methods with interrupts disabled, so no need to use
spin_lock_irqsave / spin_unlock_irqrestore for those.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by:Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/arch/mips/kernel/i8253.c b/arch/mips/kernel/i8253.c
index c2d497ceff..fc4aa07b6d 100644
--- a/arch/mips/kernel/i8253.c
+++ b/arch/mips/kernel/i8253.c
@@ -24,9 +24,7 @@ DEFINE_SPINLOCK(i8253_lock);
 static void init_pit_timer(enum clock_event_mode mode,
 			   struct clock_event_device *evt)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(&i8253_lock, flags);
+	spin_lock(&i8253_lock);
 
 	switch(mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
@@ -55,7 +53,7 @@ static void init_pit_timer(enum clock_event_mode mode,
 		/* Nothing to do here */
 		break;
 	}
-	spin_unlock_irqrestore(&i8253_lock, flags);
+	spin_unlock(&i8253_lock);
 }
 
 /*
@@ -65,12 +63,10 @@ static void init_pit_timer(enum clock_event_mode mode,
  */
 static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(&i8253_lock, flags);
+	spin_lock(&i8253_lock);
 	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
 	outb(delta >> 8 , PIT_CH0);	/* MSB */
-	spin_unlock_irqrestore(&i8253_lock, flags);
+	spin_unlock(&i8253_lock);
 
 	return 0;
 }
diff --git a/arch/x86/kernel/i8253.c b/arch/x86/kernel/i8253.c
index 377c3f8411..c76fef1ce3 100644
--- a/arch/x86/kernel/i8253.c
+++ b/arch/x86/kernel/i8253.c
@@ -38,9 +38,7 @@ struct clock_event_device *global_clock_event;
 static void init_pit_timer(enum clock_event_mode mode,
 			   struct clock_event_device *evt)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(&i8253_lock, flags);
+	spin_lock(&i8253_lock);
 
 	switch(mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
@@ -71,7 +69,7 @@ static void init_pit_timer(enum clock_event_mode mode,
 		/* Nothing to do here */
 		break;
 	}
-	spin_unlock_irqrestore(&i8253_lock, flags);
+	spin_unlock(&i8253_lock);
 }
 
 /*
@@ -81,12 +79,10 @@ static void init_pit_timer(enum clock_event_mode mode,
  */
 static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(&i8253_lock, flags);
+	spin_lock(&i8253_lock);
 	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
 	outb(delta >> 8 , PIT_CH0);	/* MSB */
-	spin_unlock_irqrestore(&i8253_lock, flags);
+	spin_unlock(&i8253_lock);
 
 	return 0;
 }