From: Ralf Baechle <ralf@linux-mips.org>
To: Andrew Morton <akpm@linux-foundation.org>,
Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH] Optimize i8259 code a bit.
Date: Sun, 28 Oct 2007 23:11:45 +0000 [thread overview]
Message-ID: <20071028231145.GA9515@linux-mips.org> (raw)
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.
arch/mips/kernel/i8253.c | 12 ++++--------
arch/x86/kernel/i8253.c | 12 ++++--------
2 files changed, 8 insertions(+), 16 deletions(-)
diff --git a/arch/mips/kernel/i8253.c b/arch/mips/kernel/i8253.c
index 5d9830d..1b54674 100644
--- a/arch/mips/kernel/i8253.c
+++ b/arch/mips/kernel/i8253.c
@@ -23,9 +23,7 @@ static 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:
@@ -54,7 +52,7 @@ 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);
}
/*
@@ -64,12 +62,10 @@ 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 a42c807..5246515 100644
--- a/arch/x86/kernel/i8253.c
+++ b/arch/x86/kernel/i8253.c
@@ -31,9 +31,7 @@ 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:
@@ -62,7 +60,7 @@ 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);
}
/*
@@ -72,12 +70,10 @@ 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;
}
next reply other threads:[~2007-10-28 15:49 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-10-28 23:11 Ralf Baechle [this message]
2007-10-28 16:54 ` [PATCH] Optimize i8259 code a bit Thomas Gleixner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20071028231145.GA9515@linux-mips.org \
--to=ralf@linux-mips.org \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.