Re: [PATCH] drm/amdgpu: simplify vram alloc logic since 2GB limitation removed

[Christian König <ckoenig.leichtzumerken@xxxxxxxxx>]

Arun please take a look at that.

Looks valid to me in general.

Thanks,
Christian.

Am 23.09.24 um 10:19 schrieb Yifan Zhang:
> Make vram alloc loop simpler after 2GB limitation removed.
>
> Signed-off-by: Yifan Zhang <yifan1.zhang@xxxxxxx>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 15 +++++----------
>   1 file changed, 5 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
> index 7d26a962f811..3d129fd61fa7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
> @@ -455,7 +455,7 @@ static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man,
>   	struct amdgpu_bo *bo = ttm_to_amdgpu_bo(tbo);
>   	u64 vis_usage = 0, max_bytes, min_block_size;
>   	struct amdgpu_vram_mgr_resource *vres;
> -	u64 size, remaining_size, lpfn, fpfn;
> +	u64 size, lpfn, fpfn;
>   	unsigned int adjust_dcc_size = 0;
>   	struct drm_buddy *mm = &mgr->mm;
>   	struct drm_buddy_block *block;
> @@ -516,25 +516,23 @@ static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man,
>   	    adev->gmc.gmc_funcs->get_dcc_alignment)
>   		adjust_dcc_size = amdgpu_gmc_get_dcc_alignment(adev);
>   
> -	remaining_size = (u64)vres->base.size;
> +	size = (u64)vres->base.size;
>   	if (bo->flags & AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS && adjust_dcc_size) {
>   		unsigned int dcc_size;
>   
>   		dcc_size = roundup_pow_of_two(vres->base.size + adjust_dcc_size);
> -		remaining_size = (u64)dcc_size;
> +		size = (u64)dcc_size;
>   
>   		vres->flags |= DRM_BUDDY_TRIM_DISABLE;
>   	}
>   
>   	mutex_lock(&mgr->lock);
> -	while (remaining_size) {
> +	while (true) {
>   		if (tbo->page_alignment)
>   			min_block_size = (u64)tbo->page_alignment << PAGE_SHIFT;
>   		else
>   			min_block_size = mgr->default_page_size;
>   
> -		size = remaining_size;
> -
>   		if (bo->flags & AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS && adjust_dcc_size)
>   			min_block_size = size;
>   		else if ((size >= (u64)pages_per_block << PAGE_SHIFT) &&
> @@ -562,10 +560,7 @@ static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man,
>   		if (unlikely(r))
>   			goto error_free_blocks;
>   
> -		if (size > remaining_size)
> -			remaining_size = 0;
> -		else
> -			remaining_size -= size;
> +		break;
>   	}
>   	mutex_unlock(&mgr->lock);
>