ttm: Provide an API for starting and stopping the delayed workqueue

We want to be able to prevent the delayed workqueue from changing state
while we're reclocking, so add an API to block and unblock it.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 3b5b094b139..4c2299299ab 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -604,6 +604,20 @@ void ttm_bo_unref(struct ttm_buffer_object **p_bo)
 }
 EXPORT_SYMBOL(ttm_bo_unref);
 
+int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev)
+{
+        return cancel_delayed_work_sync(&bdev->wq);
+}
+EXPORT_SYMBOL(ttm_bo_lock_delayed_workqueue);
+
+void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched)
+{
+        if (resched)
+                schedule_delayed_work(&bdev->wq,
+                                      ((HZ / 100) < 1) ? 1 : HZ / 100);
+}
+EXPORT_SYMBOL(ttm_bo_unlock_delayed_workqueue);
+
 static int ttm_bo_evict(struct ttm_buffer_object *bo, bool interruptible,
                         bool no_wait_reserve, bool no_wait_gpu)
 {