diff options
| author | Bhupesh Sharma <bhupesh.sharma@st.com> | 2012-03-22 07:50:37 +0400 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2012-04-10 22:46:02 +0400 |
| commit | 95faf82bd3ea607f8e1ca78930c49b71078266e6 (patch) | |
| tree | 325a5529c3c5b4d46dcbaecb3800f844321918ca /drivers/usb/gadget/uvc_queue.c | |
| parent | 7cfce77d779f43299c1cfeddd72462fed596c168 (diff) | |
| download | linux-95faf82bd3ea607f8e1ca78930c49b71078266e6.tar.xz | |
[media] usb: gadget/uvc: Remove non-required locking from 'uvc_queue_next_buffer' routine
This patch removes the non-required spinlock acquire/release calls on
'queue_irqlock' from 'uvc_queue_next_buffer' routine.
This routine is called from 'video->encode' function (which translates to either
'uvc_video_encode_bulk' or 'uvc_video_encode_isoc') in 'uvc_video.c'.
As, the 'video->encode' routines are called with 'queue_irqlock' already held,
so acquiring a 'queue_irqlock' again in 'uvc_queue_next_buffer' routine causes
a spin lock recursion.
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@st.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/usb/gadget/uvc_queue.c')
| -rw-r--r-- | drivers/usb/gadget/uvc_queue.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/drivers/usb/gadget/uvc_queue.c b/drivers/usb/gadget/uvc_queue.c index d776adb2da67..104ae9c81251 100644 --- a/drivers/usb/gadget/uvc_queue.c +++ b/drivers/usb/gadget/uvc_queue.c @@ -543,11 +543,11 @@ done: return ret; } +/* called with &queue_irqlock held.. */ static struct uvc_buffer * uvc_queue_next_buffer(struct uvc_video_queue *queue, struct uvc_buffer *buf) { struct uvc_buffer *nextbuf; - unsigned long flags; if ((queue->flags & UVC_QUEUE_DROP_INCOMPLETE) && buf->buf.length != buf->buf.bytesused) { @@ -556,14 +556,12 @@ uvc_queue_next_buffer(struct uvc_video_queue *queue, struct uvc_buffer *buf) return buf; } - spin_lock_irqsave(&queue->irqlock, flags); list_del(&buf->queue); if (!list_empty(&queue->irqqueue)) nextbuf = list_first_entry(&queue->irqqueue, struct uvc_buffer, queue); else nextbuf = NULL; - spin_unlock_irqrestore(&queue->irqlock, flags); buf->buf.sequence = queue->sequence++; do_gettimeofday(&buf->buf.timestamp); |