[PATCH] drm/amd/amdgpu: Bail out of BO node creation if not enough VRAM (v2)

[Michel Dänzer]

On 2019-06-11 6:54 p.m., StDenis, Tom wrote:
> (v2): Return 0 and set mem->mm_node to NULL.
> 
> Signed-off-by: Tom St Denis <tom.stdenis at amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 18 +++++++++++++-----
>  1 file changed, 13 insertions(+), 5 deletions(-)
> 
> [...]
>  
> @@ -284,6 +284,14 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man,
>  	if (!lpfn)
>  		lpfn = man->size;
>  
> +	/* bail out quickly if there's likely not enough VRAM for this BO */
> +	atomic64_add(mem->num_pages << PAGE_SHIFT, &mgr->usage);
> +	if (atomic64_read(&mgr->usage) > adev->gmc.mc_vram_size) {

Should probably use atomic64_add_return instead of atomic64_add +
atomic64_read.

Also, AFAICT this doesn't allow any VRAM overcommit, which seems a bit
conservative?


-- 
Earthling Michel Dänzer               |              https://www.amd.com
Libre software enthusiast             |             Mesa and X developer