Re: [PATCH v2] drm/amdgpu: skip clearing empty freed VM list on GEM close

On 2026-07-15 22:56, Bob Zhou wrote:
> amdgpu_vm_clear_freed() allocates an amdgpu_sync object and walks the VM
> reservation fences via amdgpu_sync_resv() before checking whether vm->freed
> has anything to clear. Return early when the list is empty to skip this
> overhead on a hot path (every GEM close and command submission).
>
> Signed-off-by: Bob Zhou <[email protected]>

Reviewed-by: Felix Kuehling <[email protected]>


> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> index 157d4168907ce..eb6a70fe79ceb 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> @@ -1553,6 +1553,8 @@ int amdgpu_vm_clear_freed(struct amdgpu_device *adev,
>   	struct amdgpu_sync sync;
>   	int r;
>   
> +	if (list_empty(&vm->freed))
> +		return 0;
>   
>   	/*
>   	 * Implicitly sync to command submissions in the same VM before