[PATCH 2/2] drm/amdgpu: allow GTT overcommit during bind

[Chunming Zhou]

On 2017年10月16日 17:26, Christian König wrote:
> From: Christian König <christian.koenig at amd.com>
>
> While binding BOs to GART we need to allow a bit overcommit in the GTT
> domain.
If allowing overcommit, will the new node not over the GART mc range? 
Which is also allowed?

Regards,
David Zhou
>   Otherwise we can never use the full GART space when GART size=GTT size.
>
> Signed-off-by: Christian König <christian.koenig at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c | 8 +++++---
>   1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
> index 0d15eb7d31d7..33535d347734 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
> @@ -169,7 +169,8 @@ static int amdgpu_gtt_mgr_new(struct ttm_mem_type_manager *man,
>   	int r;
>   
>   	spin_lock(&mgr->lock);
> -	if (atomic64_read(&mgr->available) < mem->num_pages) {
> +	if ((&tbo->mem == mem || tbo->mem.mem_type != TTM_PL_TT) &&
> +	    atomic64_read(&mgr->available) < mem->num_pages) {
>   		spin_unlock(&mgr->lock);
>   		return 0;
>   	}
> @@ -244,8 +245,9 @@ static void amdgpu_gtt_mgr_del(struct ttm_mem_type_manager *man,
>   uint64_t amdgpu_gtt_mgr_usage(struct ttm_mem_type_manager *man)
>   {
>   	struct amdgpu_gtt_mgr *mgr = man->priv;
> +	s64 result = man->size - atomic64_read(&mgr->available);
>   
> -	return (u64)(man->size - atomic64_read(&mgr->available)) * PAGE_SIZE;
> +	return (result > 0 ? result : 0) * PAGE_SIZE;
>   }
>   
>   /**
> @@ -265,7 +267,7 @@ static void amdgpu_gtt_mgr_debug(struct ttm_mem_type_manager *man,
>   	drm_mm_print(&mgr->mm, printer);
>   	spin_unlock(&mgr->lock);
>   
> -	drm_printf(printer, "man size:%llu pages, gtt available:%llu pages, usage:%lluMB\n",
> +	drm_printf(printer, "man size:%llu pages, gtt available:%lld pages, usage:%lluMB\n",
>   		   man->size, (u64)atomic64_read(&mgr->available),
>   		   amdgpu_gtt_mgr_usage(man) >> 20);
>   }