From 6d2199868a9aede70a4ee5fa32e6ae2800b8b25a Mon Sep 17 00:00:00 2001 From: Sergey Senozhatsky Date: Thu, 14 May 2020 18:01:41 +0200 Subject: [PATCH] media: videobuf2: add cache management members Extend vb2_buffer and vb2_queue structs with cache management members. V4L2 UAPI already contains two buffer flags which user-space, supposedly, can use to control buffer cache sync: - V4L2_BUF_FLAG_NO_CACHE_INVALIDATE - V4L2_BUF_FLAG_NO_CACHE_CLEAN None of these, however, do anything at the moment. This patch set is intended to change it. Since user-space cache management hints are supposed to be implemented on a per-buffer basis we need to extend vb2_buffer struct with two new members ->need_cache_sync_on_prepare and ->need_cache_sync_on_finish, which will store corresponding user-space hints. In order to preserve the existing behaviour, user-space cache managements flags will be handled only by those drivers that permit user-space cache hints. That's the purpose of vb2_queue ->allow_cache_hints member. Driver must set ->allow_cache_hints during queue initialisation to enable cache management hints mechanism. Signed-off-by: Sergey Senozhatsky Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- include/media/videobuf2-core.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index 9e522bd..7f39d9f 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -263,6 +263,10 @@ struct vb2_buffer { * after the 'buf_finish' op is called. * copied_timestamp: the timestamp of this capture buffer was copied * from an output buffer. + * need_cache_sync_on_prepare: when set buffer's ->prepare() function + * performs cache sync/invalidation. + * need_cache_sync_on_finish: when set buffer's ->finish() function + * performs cache sync/invalidation. * queued_entry: entry on the queued buffers list, which holds * all buffers queued from userspace * done_entry: entry on the list that stores all buffers ready @@ -273,6 +277,8 @@ struct vb2_buffer { unsigned int synced:1; unsigned int prepared:1; unsigned int copied_timestamp:1; + unsigned int need_cache_sync_on_prepare:1; + unsigned int need_cache_sync_on_finish:1; struct vb2_plane planes[VB2_MAX_PLANES]; struct list_head queued_entry; @@ -491,6 +497,9 @@ struct vb2_buf_ops { * @uses_requests: requests are used for this queue. Set to 1 the first time * a request is queued. Set to 0 when the queue is canceled. * If this is 1, then you cannot queue buffers directly. + * @allow_cache_hints: when set user-space can pass cache management hints in + * order to skip cache flush/invalidation on ->prepare() or/and + * ->finish(). * @lock: pointer to a mutex that protects the &struct vb2_queue. The * driver can set this to a mutex to let the v4l2 core serialize * the queuing ioctls. If the driver wants to handle locking @@ -567,6 +576,7 @@ struct vb2_queue { unsigned int requires_requests:1; unsigned int uses_qbuf:1; unsigned int uses_requests:1; + unsigned int allow_cache_hints:1; struct mutex *lock; void *owner; -- 2.7.4