V4L/DVB: videobuf: prepare to make locking optional in videobuf
Currently videobuf uses the vb_lock mutex to lock its data structures.
But this locking will (optionally) move into the v4l2 core, which means
that in that case vb_lock shouldn't be used since the external lock is already
held.
Prepare for this by adding a pointer to such an external mutex and
don't lock if that pointer is set.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/v4l2-mem2mem.c b/drivers/media/video/v4l2-mem2mem.c
index f45f940..ac832a2 100644
--- a/drivers/media/video/v4l2-mem2mem.c
+++ b/drivers/media/video/v4l2-mem2mem.c
@@ -421,8 +421,8 @@
src_q = v4l2_m2m_get_src_vq(m2m_ctx);
dst_q = v4l2_m2m_get_dst_vq(m2m_ctx);
- mutex_lock(&src_q->vb_lock);
- mutex_lock(&dst_q->vb_lock);
+ videobuf_queue_lock(src_q);
+ videobuf_queue_lock(dst_q);
if (src_q->streaming && !list_empty(&src_q->stream))
src_vb = list_first_entry(&src_q->stream,
@@ -450,8 +450,8 @@
}
end:
- mutex_unlock(&dst_q->vb_lock);
- mutex_unlock(&src_q->vb_lock);
+ videobuf_queue_unlock(dst_q);
+ videobuf_queue_unlock(src_q);
return rc;
}
EXPORT_SYMBOL_GPL(v4l2_m2m_poll);