pci/drm/drm_vblank_work.c

40  * generic delayed work implementation which delays work execution until a
41  * particular vblank has passed, and then executes the work at realtime
45  * re-arming work items can be easily implemented.
50 	struct drm_vblank_work *work, *next;
56 	list_for_each_entry_safe(work, next, &vblank->pending_work, node) {
57 		if (!drm_vblank_passed(count, work->count))
60 		list_del_init(&work->node);
62 		kthread_queue_work(vblank->worker, &work->base);
69 /* Handle cancelling any pending vblank work items and drop respective vblank
74 	struct drm_vblank_work *work, *next;
78 	list_for_each_entry_safe(work, next, &vblank->pending_work, node) {
79 		list_del_init(&work->node);
87  * drm_vblank_work_schedule - schedule a vblank work
88  * @work: vblank work to schedule
92  * Schedule @work for execution once the crtc vblank count reaches @count.
95  * %false the work starts to execute immediately.
98  * %true the work is deferred until the next vblank (as if @count has been
101  * If @work is already scheduled, this function will reschedule said work
102  * using the new @count. This can be used for self-rearming work items.
105  * %1 if @work was successfully (re)scheduled, %0 if it was either already
108 int drm_vblank_work_schedule(struct drm_vblank_work *work,
111 	struct drm_vblank_crtc *vblank = work->vblank;
119 	if (work->cancelling)
128 	if (list_empty(&work->node)) {
132 	} else if (work->count == count) {
139 	work->count = count;
149 		ret = kthread_queue_work(vblank->worker, &work->base);
152 			list_del_init(&work->node);
157 			list_add_tail(&work->node, &vblank->pending_work);
170  * drm_vblank_work_cancel_sync - cancel a vblank work and wait for it to
172  * @work: vblank work to cancel
174  * Cancel an already scheduled vblank work and wait for its
177  * On return, @work is guaranteed to no longer be scheduled or running, even
181  * %True if the work was cancelled before it started to execute, %false
184 bool drm_vblank_work_cancel_sync(struct drm_vblank_work *work)
186 	struct drm_vblank_crtc *vblank = work->vblank;
191 	if (!list_empty(&work->node)) {
192 		list_del_init(&work->node);
197 	work->cancelling++;
202 	if (kthread_cancel_work_sync(&work->base))
206 	work->cancelling--;
214  * drm_vblank_work_flush - wait for a scheduled vblank work to finish
216  * @work: vblank work to flush
218  * Wait until @work has finished executing once.
220 void drm_vblank_work_flush(struct drm_vblank_work *work)
222 	struct drm_vblank_crtc *vblank = work->vblank;
226 	wait_event_lock_irq(vblank->work_wait_queue, list_empty(&work->node),
230 	kthread_flush_work(&work->base);
235  * drm_vblank_work_init - initialize a vblank work item
236  * @work: vblank work item
237  * @crtc: CRTC whose vblank will trigger the work execution
238  * @func: work function to be executed
240  * Initialize a vblank work item for a specific crtc.
242 void drm_vblank_work_init(struct drm_vblank_work *work, struct drm_crtc *crtc,
243 			  void (*func)(struct kthread_work *work))
245 	kthread_init_work(&work->base, func);
246 	INIT_LIST_HEAD(&work->node);
247 	work->vblank = &crtc->dev->vblank[drm_crtc_index(crtc)];