[PATCH 2/3] drm/amdgpu: Don't evict other BOs from VRAM for page faults

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

If there is no free space in CPU visible VRAM for the faulting BO, move
it to GTT instead of evicting other BOs from CPU visible VRAM.

Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
index b3252bc8fe51..41ee353b22c8 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
@@ -940,7 +940,6 @@ int amdgpu_bo_fault_reserve_notify(struct ttm_buffer_object *bo)
 	struct amdgpu_device *adev = amdgpu_ttm_adev(bo->bdev);
 	struct amdgpu_bo *abo;
 	unsigned long offset, size;
-	int r;
 
 	if (!amdgpu_ttm_bo_is_amdgpu_bo(bo))
 		return 0;
@@ -960,22 +959,17 @@ int amdgpu_bo_fault_reserve_notify(struct ttm_buffer_object *bo)
 		return -EINVAL;
 
 	/* hurrah the memory is not visible ! */
-	amdgpu_ttm_placement_from_domain(abo, AMDGPU_GEM_DOMAIN_VRAM);
+	amdgpu_ttm_placement_from_domain(abo, AMDGPU_GEM_DOMAIN_VRAM |
+					 AMDGPU_GEM_DOMAIN_GTT);
 	abo->placements[0].lpfn = adev->mc.visible_vram_size >> PAGE_SHIFT;
-	r = ttm_bo_validate(bo, &abo->placement, false, false);
-	if (unlikely(r == -ENOMEM)) {
-		amdgpu_ttm_placement_from_domain(abo, AMDGPU_GEM_DOMAIN_GTT);
-		return ttm_bo_validate(bo, &abo->placement, false, false);
-	} else if (unlikely(r != 0)) {
-		return r;
-	}
 
-	offset = bo->mem.start << PAGE_SHIFT;
-	/* this should never happen */
-	if ((offset + size) > adev->mc.visible_vram_size)
-		return -EINVAL;
+	/* Only set GTT as busy placement; if there is no space in CPU visible
+	 * VRAM, move this BO to GTT instead of evicting other BOs
+	 */
+	abo->placement.busy_placement = &abo->placements[1];
+	abo->placement.num_busy_placement = 1;
 
-	return 0;
+	return ttm_bo_validate(bo, &abo->placement, false, false);
 }
 
 /**
-- 
2.11.0