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mips, x86: optimize the i8259 code a bit

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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>
This commit is contained in:
Ralf Baechle
2008-01-30 13:30:47 +01:00
committed by Ingo Molnar
parent b263295dbf
commit 5f627f8e12
2 changed files with 8 additions and 16 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
arch/mips/kernel/i8253.c
View File

@@ -24,9 +24,7 @@ DEFINE_SPINLOCK(i8253_lock);
static void init_pit_timer(enum clock_event_mode mode, static void init_pit_timer(enum clock_event_mode mode,
struct clock_event_device *evt) struct clock_event_device *evt)
{ {
unsigned long flags; spin_lock(&i8253_lock);
spin_lock_irqsave(&i8253_lock, flags);
switch(mode) { switch(mode) {
case CLOCK_EVT_MODE_PERIODIC: case CLOCK_EVT_MODE_PERIODIC:
@@ -55,7 +53,7 @@ static void init_pit_timer(enum clock_event_mode mode,
/* Nothing to do here */ /* Nothing to do here */
break; 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) static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
{ {
unsigned long flags; spin_lock(&i8253_lock);
spin_lock_irqsave(&i8253_lock, flags);
outb_p(delta & 0xff , PIT_CH0); /* LSB */ outb_p(delta & 0xff , PIT_CH0); /* LSB */
outb(delta >> 8 , PIT_CH0); /* MSB */ outb(delta >> 8 , PIT_CH0); /* MSB */
spin_unlock_irqrestore(&i8253_lock, flags); spin_unlock(&i8253_lock);
return 0; return 0;
} }

12
arch/x86/kernel/i8253.c
View File

@@ -38,9 +38,7 @@ struct clock_event_device *global_clock_event;
static void init_pit_timer(enum clock_event_mode mode, static void init_pit_timer(enum clock_event_mode mode,
struct clock_event_device *evt) struct clock_event_device *evt)
{ {
unsigned long flags; spin_lock(&i8253_lock);
spin_lock_irqsave(&i8253_lock, flags);
switch(mode) { switch(mode) {
case CLOCK_EVT_MODE_PERIODIC: case CLOCK_EVT_MODE_PERIODIC:
@@ -71,7 +69,7 @@ static void init_pit_timer(enum clock_event_mode mode,
/* Nothing to do here */ /* Nothing to do here */
break; 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) static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
{ {
unsigned long flags; spin_lock(&i8253_lock);
spin_lock_irqsave(&i8253_lock, flags);
outb_p(delta & 0xff , PIT_CH0); /* LSB */ outb_p(delta & 0xff , PIT_CH0); /* LSB */
outb(delta >> 8 , PIT_CH0); /* MSB */ outb(delta >> 8 , PIT_CH0); /* MSB */
spin_unlock_irqrestore(&i8253_lock, flags); spin_unlock(&i8253_lock);
return 0; return 0;
} }