On 24/01/2024 16:35, Benjamin Gaignard wrote: > > Le 24/01/2024 à 13:52, Hans Verkuil a écrit : >> On 19/01/2024 10:49, Benjamin Gaignard wrote: >>> Allow to delete buffers on capture queue because it the one which >>> own the decoded buffers. After a dynamic resolution change lot of >>> them could remain allocated but won't be used anymore so deleting >>> them save memory. >>> Do not add this feature on output queue because the buffers are >>> smaller, fewer and always recycled even after a dynamic resolution >>> change. >>> >>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx> >>> --- >>> drivers/media/platform/verisilicon/hantro_drv.c | 1 + >>> drivers/media/platform/verisilicon/hantro_v4l2.c | 1 + >>> 2 files changed, 2 insertions(+) >>> >>> diff --git a/drivers/media/platform/verisilicon/hantro_drv.c b/drivers/media/platform/verisilicon/hantro_drv.c >>> index db3df6cc4513..f6b0a676a740 100644 >>> --- a/drivers/media/platform/verisilicon/hantro_drv.c >>> +++ b/drivers/media/platform/verisilicon/hantro_drv.c >>> @@ -248,6 +248,7 @@ queue_init(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq) >>> dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY; >>> dst_vq->lock = &ctx->dev->vpu_mutex; >>> dst_vq->dev = ctx->dev->v4l2_dev.dev; >>> + src_vq->supports_delete_bufs = true; >> As I mentioned, I remain unconvinced by this. It is just making the API inconsistent >> since if you support delete_bufs, then why support it for one queue only and not both? > > Because the both queues don't handle the same type of data. > For example for a stateless decoder, for me, it makes sense to allow delete decoded frames > if they won't be used anymore but that won't makes sense for bitstream buffers. But is there any reason why you wouldn't support this feature? We support VIDIOC_CREATE_BUFS as well, even though most drivers do not need it, but it is cheap to add. Deleting buffers is a generic feature, and I don't see why you wouldn't just offer it for both queues. Regards, Hans > >> >>> return vb2_queue_init(dst_vq); >>> } >>> diff --git a/drivers/media/platform/verisilicon/hantro_v4l2.c b/drivers/media/platform/verisilicon/hantro_v4l2.c >>> index 941fa23c211a..34eab90e8a42 100644 >>> --- a/drivers/media/platform/verisilicon/hantro_v4l2.c >>> +++ b/drivers/media/platform/verisilicon/hantro_v4l2.c >>> @@ -756,6 +756,7 @@ const struct v4l2_ioctl_ops hantro_ioctl_ops = { >>> .vidioc_dqbuf = v4l2_m2m_ioctl_dqbuf, >>> .vidioc_prepare_buf = v4l2_m2m_ioctl_prepare_buf, >>> .vidioc_create_bufs = v4l2_m2m_ioctl_create_bufs, >>> + .vidioc_delete_bufs = v4l2_m2m_ioctl_delete_bufs, >>> .vidioc_expbuf = v4l2_m2m_ioctl_expbuf, >>> .vidioc_subscribe_event = v4l2_ctrl_subscribe_event, >> In my view setting vidioc_delete_bufs should enable this feature, and if >> for some strange reason only one queue support it, then make a wrapper >> callback that returns an error when used with the wrong queue. >> >> Also note that patch 6/8 never checks for q->supports_delete_bufs in >> vb2_core_delete_bufs(), which is wrong! > > I will fix that in next version. > Regards, > Benjamin > >> >> Regards, >> >> Hans >>