From c7a472297169156252a50d76965eb36b081186e2 Mon Sep 17 00:00:00 2001 From: Simon Ser Date: Fri, 14 Jul 2023 11:13:03 +0000 Subject: drm/syncobj: add IOCTL to register an eventfd MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Introduce a new DRM_IOCTL_SYNCOBJ_EVENTFD IOCTL which signals an eventfd from a syncobj. This is useful for Wayland compositors to handle wait-before-submit. Wayland clients can send a timeline point to the compositor before the point has materialized yet, then compositors can wait for the point to materialize via this new IOCTL. The existing DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT IOCTL is not suitable because it blocks. Compositors want to integrate the wait with their poll(2)-based event loop. Requirements for new uAPI: - User-space patch: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4262 - IGT: https://lists.freedesktop.org/archives/igt-dev/2023-July/057893.html v2: - Wait for fence when flags is zero - Improve documentation (Pekka) - Rename IOCTL (Christian) - Fix typo in drm_syncobj_add_eventfd() (Christian) v3: - Link user-space + IGT patches - Add reference from overview docs v4: fix IOCTL number conflict with GETFB2 (Nicholas Choi, Vitaly Prosyak) Signed-off-by: Simon Ser Reviewed-by: Christian König Acked-by: Pekka Paalanen Cc: Jason Ekstrand Cc: Daniel Vetter Cc: Bas Nieuwenhuizen Cc: Daniel Stone Cc: James Jones Cc: Austin Shafer Cc: Vitaly Prosyak Link: https://patchwork.freedesktop.org/patch/msgid/20230714111257.11940-1-contact@emersion.fr --- include/drm/drm_syncobj.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'include/drm/drm_syncobj.h') diff --git a/include/drm/drm_syncobj.h b/include/drm/drm_syncobj.h index 6cf7243a1dc5..b40052132e52 100644 --- a/include/drm/drm_syncobj.h +++ b/include/drm/drm_syncobj.h @@ -54,7 +54,11 @@ struct drm_syncobj { */ struct list_head cb_list; /** - * @lock: Protects &cb_list and write-locks &fence. + * @ev_fd_list: List of registered eventfd. + */ + struct list_head ev_fd_list; + /** + * @lock: Protects &cb_list and &ev_fd_list, and write-locks &fence. */ spinlock_t lock; /** -- cgit v1.2.3