[PATCH 2/2] drm/amdgpu: Use last_unlocked fence for unlocked update

[Christian König]

Am 26.03.22 um 01:56 schrieb Philip Yang:
> MMU callback update page table set unlocked flag, add callback tlb_cb to
> vm->last_unlocked fence, and pass it back to upper layer to wait for
> page table update done.
>
> Signed-off-by: Philip Yang <Philip.Yang at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> index 48f326609976..aac1b625194f 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> @@ -927,7 +927,10 @@ int amdgpu_vm_bo_update_mapping(struct amdgpu_device *adev,
>   
>   	r = vm->update_funcs->commit(&params, fence);
>   
> -	if (!unlocked && (!(flags & AMDGPU_PTE_VALID) || params.table_freed)) {
> +	if (!(flags & AMDGPU_PTE_VALID) || params.table_freed) {

Dropping the check for the unlocked flag here seems to be ok.

> +		if (unlocked && fence)
> +			*fence = dma_fence_get(vm->last_unlocked);
> +

But that doesn't seems to make sense, fence should already contain the 
necessary fence object if any.

Regards,
Christian.


>   		tlb_cb->vm = vm;
>   		if (!fence || !*fence ||
>   		    dma_fence_add_callback(*fence, &tlb_cb->cb,