linux-kernel - [PATCH 7/7] [media] cx88: don't use atomic

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Date:	Sun, 1 May 2011 04:31:40 -0500
From:	Jonathan Nieder <jrnieder@...il.com>
To:	linux-media@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org,
	Mauro Carvalho Chehab <mchehab@...hat.com>,
	Dan Carpenter <error27@...il.com>,
	Hans Verkuil <hverkuil@...all.nl>, Andi Huber <hobrom@....at>,
	Marlon de Boer <marlon@...es.nl>,
	Damien Churchill <damoxc@...il.com>
Subject: [PATCH 7/7] [media] cx88: don't use atomic_t for core->users

users is always read or written with core->lock held.  A plain int is
simpler and faster.

Tested-by: Andi Huber <hobrom@....at>
Tested-by: Marlon de Boer <marlon@...es.nl>
Signed-off-by: Jonathan Nieder <jrnieder@...il.com>
---
That's the end of the series.  Thanks for reading.

 drivers/media/video/cx88/cx88-video.c |    5 +++--
 drivers/media/video/cx88/cx88.h       |    2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/media/video/cx88/cx88-video.c b/drivers/media/video/cx88/cx88-video.c
index 508dabb..51d1b09 100644
--- a/drivers/media/video/cx88/cx88-video.c
+++ b/drivers/media/video/cx88/cx88-video.c
@@ -823,7 +823,7 @@ static int video_open(struct file *file)
 		call_all(core, tuner, s_radio);
 	}
 
-	atomic_inc(&core->users);
+	core->users++;
 	mutex_unlock(&core->lock);
 
 	return 0;
@@ -921,7 +921,8 @@ static int video_release(struct file *file)
 	file->private_data = NULL;
 	kfree(fh);
 
-	if(atomic_dec_and_test(&dev->core->users))
+	dev->core->users--;
+	if (!dev->core->users)
 		call_all(dev->core, core, s_power, 0);
 	mutex_unlock(&dev->core->lock);
 
diff --git a/drivers/media/video/cx88/cx88.h b/drivers/media/video/cx88/cx88.h
index 09e329f..887a978 100644
--- a/drivers/media/video/cx88/cx88.h
+++ b/drivers/media/video/cx88/cx88.h
@@ -383,7 +383,7 @@ struct cx88_core {
 	struct mutex               lock;
 	/* various v4l controls */
 	u32                        freq;
-	atomic_t		   users;
+	int                        users;
 	int                        mpeg_users;
 
 	/* cx88-video needs to access cx8802 for hybrid tuner pll access. */
-- 
1.7.5

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