drm/amdgpu: minor optimize VM moved handling v2

Try to lock moved BOs if it's successful we can update the
PTEs directly to the new location.

v2: rebase

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 14 insertions, 1 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 3632c69f1814..c1c5ccdee783 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1697,18 +1697,31 @@ int amdgpu_vm_handle_moved(struct amdgpu_device *adev,
         spin_lock(&vm->status_lock);
         while (!list_empty(&vm->moved)) {
                 struct amdgpu_bo_va *bo_va;
+                struct reservation_object *resv;
 
                 bo_va = list_first_entry(&vm->moved,
                         struct amdgpu_bo_va, base.vm_status);
                 spin_unlock(&vm->status_lock);
 
+                resv = bo_va->base.bo->tbo.resv;
+
                 /* Per VM BOs never need to bo cleared in the page tables */
-                clear = bo_va->base.bo->tbo.resv != vm->root.base.bo->tbo.resv;
+                if (resv == vm->root.base.bo->tbo.resv)
+                        clear = false;
+                /* Try to reserve the BO to avoid clearing its ptes */
+                else if (reservation_object_trylock(resv))
+                        clear = false;
+                /* Somebody else is using the BO right now */
+                else
+                        clear = true;
 
                 r = amdgpu_vm_bo_update(adev, bo_va, clear);
                 if (r)
                         return r;
 
+                if (!clear && resv != vm->root.base.bo->tbo.resv)
+                        reservation_object_unlock(resv);
+
                 spin_lock(&vm->status_lock);
         }
         spin_unlock(&vm->status_lock);