[media] cx88: don't use atomic_t for core->mpeg_users

mpeg_users is always read or written with core->lock held except
in mpeg_release (where it looks like a bug).  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>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 6 insertions, 5 deletions

diff --git a/drivers/media/video/cx88/cx88-blackbird.c b/drivers/media/video/cx88/cx88-blackbird.c
index fa8e347c448c..11e49bbc4a66 100644
--- a/drivers/media/video/cx88/cx88-blackbird.c
+++ b/drivers/media/video/cx88/cx88-blackbird.c
@@ -1073,7 +1073,7 @@ static int mpeg_open(struct file *file)
                 return err;
         }
 
-        if (!atomic_read(&dev->core->mpeg_users) && blackbird_initialize_codec(dev) < 0) {
+        if (!dev->core->mpeg_users && blackbird_initialize_codec(dev) < 0) {
                 drv->request_release(drv);
                 mutex_unlock(&dev->core->lock);
                 return -EINVAL;
@@ -1101,7 +1101,7 @@ static int mpeg_open(struct file *file)
         cx88_set_scale(dev->core, dev->width, dev->height,
                         fh->mpegq.field);
 
-        atomic_inc(&dev->core->mpeg_users);
+        dev->core->mpeg_users++;
         mutex_unlock(&dev->core->lock);
         return 0;
 }
@@ -1112,7 +1112,9 @@ static int mpeg_release(struct file *file)
         struct cx8802_dev *dev = fh->dev;
         struct cx8802_driver *drv = NULL;
 
-        if (dev->mpeg_active && atomic_read(&dev->core->mpeg_users) == 1)
+        mutex_lock(&dev->core->lock);
+
+        if (dev->mpeg_active && dev->core->mpeg_users == 1)
                 blackbird_stop_codec(dev);
 
         cx8802_cancel_buffers(fh->dev);
@@ -1121,7 +1123,6 @@ static int mpeg_release(struct file *file)
 
         videobuf_mmap_free(&fh->mpegq);
 
-        mutex_lock(&dev->core->lock);
         file->private_data = NULL;
         kfree(fh);
 
@@ -1131,7 +1132,7 @@ static int mpeg_release(struct file *file)
         if (drv)
                 drv->request_release(drv);
 
-        atomic_dec(&dev->core->mpeg_users);
+        dev->core->mpeg_users--;
 
         mutex_unlock(&dev->core->lock);