[PATCH v2 2/2] drm/ttm: Move pinned objects off LRU lists when pinning

[Thomas Hellström]

The ttm_bo_pin() and ttm_bo_unpin() functions weren't moving their
resources off the LRU list to the unevictable list.

Make sure that happens so that pinned objects don't accidently linger
on the LRU lists, and also make sure to move them back once they
are unpinned.

v2:
- Removing from a bulk move must be done with the pin-count still zero.

Cc: Christian König <christian.koenig at amd.com>
Cc: Matthew Brost <matthew.brost at intel.com>
Cc: <dri-devel at lists.freedesktop.org>
Signed-off-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
Reviewed-by: Christian König <christian.koenig at amd.com> #v1
---
 drivers/gpu/drm/ttm/ttm_bo.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index ae29915c52c0..38c99acbda76 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -592,8 +592,10 @@ void ttm_bo_pin(struct ttm_buffer_object *bo)
 	dma_resv_assert_held(bo->base.resv);
 	WARN_ON_ONCE(!kref_read(&bo->kref));
 	spin_lock(&bo->bdev->lru_lock);
-	if (bo->resource)
+	if (bo->resource) {
 		ttm_resource_del_bulk_move(bo->resource, bo);
+		ttm_resource_move_to_lru_tail(bo->resource);
+	}
 	++bo->pin_count;
 	spin_unlock(&bo->bdev->lru_lock);
 }
@@ -613,9 +615,10 @@ void ttm_bo_unpin(struct ttm_buffer_object *bo)
 		return;
 
 	spin_lock(&bo->bdev->lru_lock);
-	--bo->pin_count;
-	if (bo->resource)
+	if (!--bo->pin_count && bo->resource) {
 		ttm_resource_add_bulk_move(bo->resource, bo);
+		ttm_resource_move_to_lru_tail(bo->resource);
+	}
 	spin_unlock(&bo->bdev->lru_lock);
 }
 EXPORT_SYMBOL(ttm_bo_unpin);
-- 
2.46.0