Re: [PATCH] dma-buf: system_heap: Avoid warning on mid-order allocations

From: Daniel Vetter
Date: Tue Sep 14 2021 - 09:57:14 EST


On Thu, Sep 09, 2021 at 02:37:41AM +0000, John Stultz wrote:
> When trying to do mid-order allocations, set __GFP_NOWARN to
> avoid warning messages if the allocation fails, as we will
> still fall back to single page allocatitions in that case.
> This is the similar to what we already do for large order
> allocations.
>
> Cc: Daniel Vetter <daniel@xxxxxxxx>
> Cc: Christian Koenig <christian.koenig@xxxxxxx>
> Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
> Cc: Liam Mark <lmark@xxxxxxxxxxxxxx>
> Cc: Chris Goldsworthy <cgoldswo@xxxxxxxxxxxxxx>
> Cc: Laura Abbott <labbott@xxxxxxxxxx>
> Cc: Brian Starkey <Brian.Starkey@xxxxxxx>
> Cc: Hridya Valsaraju <hridya@xxxxxxxxxx>
> Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> Cc: Sandeep Patil <sspatil@xxxxxxxxxx>
> Cc: Daniel Mentz <danielmentz@xxxxxxxxxx>
> Cc: Ørjan Eide <orjan.eide@xxxxxxx>
> Cc: Robin Murphy <robin.murphy@xxxxxxx>
> Cc: Simon Ser <contact@xxxxxxxxxxx>
> Cc: James Jones <jajones@xxxxxxxxxx>
> Cc: Leo Yan <leo.yan@xxxxxxxxxx>
> Cc: linux-media@xxxxxxxxxxxxxxx
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>

Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx>

> ---
> drivers/dma-buf/heaps/system_heap.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c
> index 23a7e74ef966..f57a39ddd063 100644
> --- a/drivers/dma-buf/heaps/system_heap.c
> +++ b/drivers/dma-buf/heaps/system_heap.c
> @@ -40,11 +40,12 @@ struct dma_heap_attachment {
> bool mapped;
> };
>
> +#define LOW_ORDER_GFP (GFP_HIGHUSER | __GFP_ZERO | __GFP_COMP)
> +#define MID_ORDER_GFP (LOW_ORDER_GFP | __GFP_NOWARN)
> #define HIGH_ORDER_GFP (((GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN \
> | __GFP_NORETRY) & ~__GFP_RECLAIM) \
> | __GFP_COMP)
> -#define LOW_ORDER_GFP (GFP_HIGHUSER | __GFP_ZERO | __GFP_COMP)
> -static gfp_t order_flags[] = {HIGH_ORDER_GFP, LOW_ORDER_GFP, LOW_ORDER_GFP};
> +static gfp_t order_flags[] = {HIGH_ORDER_GFP, MID_ORDER_GFP, LOW_ORDER_GFP};
> /*
> * The selection of the orders used for allocation (1MB, 64K, 4K) is designed
> * to match with the sizes often found in IOMMUs. Using order 4 pages instead
> --
> 2.25.1
>

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch