Hello, On Wednesday, April 06, 2011 5:03 AM Pawel Osciak wrote: > On Sun, Apr 3, 2011 at 22:49, Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> wrote: > > Hello, > > > > On Monday, April 04, 2011 1:51 AM Pawel Osciak wrote: > > > >> Drivers are now required to implement the stop_streaming() callback > >> to ensure that all ongoing hardware operations are finished and their > >> ownership of buffers is ceded. > >> Drivers do not have to call vb2_buffer_done() for each buffer they own > >> anymore. > >> Also remove the return value from the callback. > >> > >> Signed-off-by: Pawel Osciak <pawel@xxxxxxxxxx> > >> --- > >> drivers/media/video/videobuf2-core.c | 16 ++++++++++++++-- > >> include/media/videobuf2-core.h | 16 +++++++--------- > >> 2 files changed, 21 insertions(+), 11 deletions(-) > >> > >> diff --git a/drivers/media/video/videobuf2-core.c b/drivers/media/video/videobuf2-core.c > >> index 6e69584..59d5e8b 100644 > >> --- a/drivers/media/video/videobuf2-core.c > >> +++ b/drivers/media/video/videobuf2-core.c > >> @@ -640,6 +640,9 @@ void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state) > >> struct vb2_queue *q = vb->vb2_queue; > >> unsigned long flags; > >> > >> + if (atomic_read(&q->queued_count) == 0) > >> + return; > >> + > >> if (vb->state != VB2_BUF_STATE_ACTIVE) > >> return; > >> > >> @@ -1178,12 +1181,20 @@ static void __vb2_queue_cancel(struct vb2_queue *q) > >> unsigned int i; > >> > >> /* > >> - * Tell driver to stop all transactions and release all queued > >> + * Tell the driver to stop all transactions and release all queued > >> * buffers. > >> */ > >> if (q->streaming) > >> call_qop(q, stop_streaming, q); > >> + > >> + /* > >> + * All buffers should now not be in use by the driver anymore, but we > >> + * have to manually set queued_count to 0, as the driver was not > >> + * required to call vb2_buffer_done() from stop_streaming() for all > >> + * buffers it had queued. > >> + */ > >> q->streaming = 0; > >> + atomic_set(&q->queued_count, 0); > > > > If you removed the need to call vb2_buffer_done() then you must also call > > wake_up_all(&q->done_wq) to wake any other threads/processes that might be > > sleeping waiting for buffers. > > You made me doubt myself for a second there, but the patch is correct. > There is a call to wake_up_all a few lines below this. Yes, I must have been blind or really tired that I've missed it. I'm sorry for the confusion. Best regards -- Marek Szyprowski Samsung Poland R&D Center -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
