[PATCH v5 4/9] drm/panthor: Don't call drm_gpuvm_bo_extobj_add() if the object is private

[Boris Brezillon <boris.brezillon@collabora.com>]

drm_gpuvm_bo_extobj_add() is a NOP if the object is private, but it
forces us to take/release the VM resv lock, so let's do that only when
we know the object can be shared.

v3:
- New commit

v4:
- Collect R-bs

v5:
- No changes

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
---
 drivers/gpu/drm/panthor/panthor_mmu.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
index f8c41e36afa4..f490e0bf6cac 100644
--- a/drivers/gpu/drm/panthor/panthor_mmu.c
+++ b/drivers/gpu/drm/panthor/panthor_mmu.c
@@ -1283,9 +1283,11 @@ static int panthor_vm_prepare_map_op_ctx(struct panthor_vm_op_ctx *op_ctx,
 	}
 
 	/* Insert BO into the extobj list last, when we know nothing can fail. */
-	dma_resv_lock(panthor_vm_resv(vm), NULL);
-	drm_gpuvm_bo_extobj_add(op_ctx->map.vm_bo);
-	dma_resv_unlock(panthor_vm_resv(vm));
+	if (bo->base.base.resv != panthor_vm_resv(vm)) {
+		dma_resv_lock(panthor_vm_resv(vm), NULL);
+		drm_gpuvm_bo_extobj_add(op_ctx->map.vm_bo);
+		dma_resv_unlock(panthor_vm_resv(vm));
+	}
 
 	return 0;
 
-- 
2.53.0