Re: [PATCH] drm/amd/amdgpu:flush ttm delayed work before cancel_sync

["Christian König" <ckoenig.leichtzumerken@gmail.com>]

Am 17.08.21 um 11:50 schrieb YuBiao Wang:
> [Why]
> In some cases when we unload driver, warning call trace
> will show up in vram_mgr_fini which claims that LRU is not empty, caused
> by the ttm bo inside delay deleted queue.
>
> [How]
> We should flush delayed work to make sure the delay deleting is done.
>
> Signed-off-by: YuBiao Wang <YuBiao.Wang@amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 4d266c40382c..0b5764aa98a4 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -3824,8 +3824,10 @@ void amdgpu_device_fini_hw(struct amdgpu_device *adev)
>   {
>   	dev_info(adev->dev, "amdgpu: finishing device.\n");
>   	flush_delayed_work(&adev->delayed_init_work);
> -	if (adev->mman.initialized)
> +	if (adev->mman.initialized) {
> +		flush_delayed_work(&adev->mman.bdev.wq);
>   		ttm_bo_lock_delayed_workqueue(&adev->mman.bdev);
> +	}

If you flush the delayed work you can drop the call to 
ttm_bo_lock_delayed_workqueue().

It would also be nice to have to wrap this into a 
ttm_bo_flush_delayed_workqueue() function.

Apart from that looks good to me,
Christian.

>   	adev->shutdown = true;
>   
>   	/* make sure IB test finished before entering exclusive mode