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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>
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Ralf Baechle authored and Ingo Molnar committed Jan 30, 2008
1 parent b263295 commit 5f627f8
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Showing 2 changed files with 8 additions and 16 deletions.
12 changes: 4 additions & 8 deletions arch/mips/kernel/i8253.c
Original file line number Diff line number Diff line change
Expand Up @@ -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:
Expand Down Expand Up @@ -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);
}

/*
Expand All @@ -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;
}
Expand Down
12 changes: 4 additions & 8 deletions arch/x86/kernel/i8253.c
Original file line number Diff line number Diff line change
Expand Up @@ -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:
Expand Down Expand Up @@ -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);
}

/*
Expand All @@ -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;
}
Expand Down

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