[PATCH] drm/ttm: Schedule out if possibe in bo delayed delete worker

[xinhui pan]

The delayed delete list is per device which might be very huge. And in
a heavy workload test, the list might always not be empty. That will
trigger any RCU stall warnings or softlockups in non-preemptible kernels
Lets do schedule out if possible in that case.

Signed-off-by: xinhui pan <xinhui.pan at amd.com>
---
 drivers/gpu/drm/ttm/ttm_bo.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 9e07c3f75156..b8d853cab33b 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -541,6 +541,7 @@ static bool ttm_bo_delayed_delete(struct ttm_bo_device *bdev, bool remove_all)
 		}
 
 		ttm_bo_put(bo);
+		cond_resched();
 		spin_lock(&glob->lru_lock);
 	}
 	list_splice_tail(&removed, &bdev->ddestroy);
-- 
2.17.1