From: =?UTF-8?q?Christian=20K=C3=B6nig?= <christian.koenig@amd.com>
Date: Fri, 1 Dec 2017 13:28:46 +0100
Subject: drm/amdgpu: avoid the modulo in amdgpu_vm_get_entry
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Git-commit: e3a1b32a12ef83e260a307e678d053d5f4570acd
Patch-mainline: v4.16-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

We can do this with a simple mask as well.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1285,11 +1285,11 @@ void amdgpu_vm_get_entry(struct amdgpu_p
 	*parent = NULL;
 	*entry = &p->vm->root;
 	while ((*entry)->entries) {
-		unsigned idx = addr >> amdgpu_vm_level_shift(p->adev, level++);
+		unsigned shift = amdgpu_vm_level_shift(p->adev, level++);
 
-		idx %= amdgpu_bo_size((*entry)->base.bo) / 8;
 		*parent = *entry;
-		*entry = &(*entry)->entries[idx];
+		*entry = &(*entry)->entries[addr >> shift];
+		addr &= (1ULL << shift) - 1;
 	}
 
 	if (level != p->adev->vm_manager.num_level)