Add a DRM_XE_NOTIFY watch type for asynchronous error notifications from the DRM_XE kernel module.
The reason for not registering a DRM - wide notification type is that the notification type is 24 bits wide, the subtype is only 8, If this is a concern one could define the DRM - wide subtypes to be per driver, not common across DRM. Also export the init_watch() function for use from kernel drivers. Use EXPORT_SYMBOL() to align with other exports from the same file. Assisted-by: GitHub_Copilot:claude-sonnet-4.6 Signed-off-by: Thomas Hellström <[email protected]> --- include/uapi/drm/xe_drm.h | 4 ++-- include/uapi/linux/watch_queue.h | 3 ++- kernel/watch_queue.c | 13 ++++++++++--- 3 files changed, 14 insertions(+), 6 deletions(-) diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h index bebb0167bd31..8d5e3f06b8d4 100644 --- a/include/uapi/drm/xe_drm.h +++ b/include/uapi/drm/xe_drm.h @@ -2550,8 +2550,8 @@ struct drm_xe_exec_queue_set_property { * preempt-fence mode or not restartable. * * An optional @timestamp_ns can be provided to measure the latency between - * event delivery and the point the worker is queued; the driver logs this - * once all sanity checks have passed. + * event delivery and locking; the driver logs this regardless of whether the + * VM was paused. */ /** diff --git a/include/uapi/linux/watch_queue.h b/include/uapi/linux/watch_queue.h index c3d8320b5d3a..c800c153989d 100644 --- a/include/uapi/linux/watch_queue.h +++ b/include/uapi/linux/watch_queue.h @@ -14,7 +14,8 @@ enum watch_notification_type { WATCH_TYPE_META = 0, /* Special record */ WATCH_TYPE_KEY_NOTIFY = 1, /* Key change event notification */ - WATCH_TYPE__NR = 2 + WATCH_TYPE_DRM_XE_NOTIFY = 2, /* DRM device event notification */ + WATCH_TYPE__NR = 3 }; enum watch_meta_notification_subtype { diff --git a/kernel/watch_queue.c b/kernel/watch_queue.c index 538520861e8b..701b5c388808 100644 --- a/kernel/watch_queue.c +++ b/kernel/watch_queue.c @@ -445,11 +445,17 @@ static void put_watch(struct watch *watch) } /** - * init_watch - Initialise a watch + * init_watch() - Initialise a watch subscription * @watch: The watch to initialise. - * @wqueue: The queue to assign. + * @wqueue: The watch queue (notification pipe) to associate with the watch. * - * Initialise a watch and set the watch queue. + * Initialise a newly allocated watch object and associate it with @wqueue. + * The caller must subsequently set @watch->id and @watch->info_id before + * calling add_watch_to_object() to subscribe the watch to a notification + * source. + * + * The watch queue reference is held internally; call put_watch_queue() if + * the watch is not successfully passed to add_watch_to_object(). */ void init_watch(struct watch *watch, struct watch_queue *wqueue) { @@ -458,6 +464,7 @@ void init_watch(struct watch *watch, struct watch_queue *wqueue) INIT_HLIST_NODE(&watch->queue_node); rcu_assign_pointer(watch->queue, wqueue); } +EXPORT_SYMBOL(init_watch); static int add_one_watch(struct watch *watch, struct watch_list *wlist, struct watch_queue *wqueue) { -- 2.54.0
