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From: Jonathan Nieder <jrnieder@gmail.com>
To: linux-media@vger.kernel.org
Cc: linux-kernel@vger.kernel.org,
	Mauro Carvalho Chehab <mchehab@redhat.com>,
	Dan Carpenter <error27@gmail.com>,
	Hans Verkuil <hverkuil@xs4all.nl>, Andi Huber <hobrom@gmx.at>,
	Marlon de Boer <marlon@hyves.nl>,
	Damien Churchill <damoxc@gmail.com>
Subject: [PATCH 7/7] [media] cx88: don't use atomic_t for core->users
Date: Sun, 1 May 2011 04:31:40 -0500	[thread overview]
Message-ID: <20110501093140.GG18380@elie> (raw)
In-Reply-To: <20110501091710.GA18263@elie>

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

Tested-by: Andi Huber <hobrom@gmx.at>
Tested-by: Marlon de Boer <marlon@hyves.nl>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.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


  parent reply	other threads:[~2011-05-01  9:31 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-01  9:17 [PATCH v2.6.38 resend 0/7] cx88 deadlock and data races Jonathan Nieder
2011-05-01  9:29 ` [PATCH 1/7] [media] cx88: protect per-device driver list with device lock Jonathan Nieder
2011-05-01  9:29 ` [PATCH 2/7] [media] cx88: fix locking of sub-driver operations Jonathan Nieder
2011-05-01  9:29 ` [PATCH 3/7] [media] cx88: hold device lock during sub-driver initialization Jonathan Nieder
2011-05-01  9:30 ` [PATCH 4/7] [media] cx88: protect cx8802_devlist with a mutex Jonathan Nieder
2011-05-01  9:30 ` [PATCH 5/7] [media] cx88: gracefully reject attempts to use unregistered cx88-blackbird driver Jonathan Nieder
2011-05-01  9:31 ` [PATCH 6/7] [media] cx88: don't use atomic_t for core->mpeg_users Jonathan Nieder
2011-05-01  9:31 ` Jonathan Nieder [this message]
2011-05-01 11:27 ` [PATCH v2.6.38 resend 0/7] cx88 deadlock and data races linuxtv
2011-05-02  8:19   ` cx88 sound does not always work (Re: [PATCH v2.6.38 resend 0/7] cx88 deadlock and data races) Jonathan Nieder
2011-05-02 18:40     ` linuxtv
2011-05-04  9:09       ` hubstar
2011-05-04  9:23         ` cx88 sound does not always work Jonathan Nieder
2011-05-04  9:55           ` hubstar

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