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

From: Daniel Vetter <daniel@ffwll.ch>
To: John Stultz <john.stultz@linaro.org>
Cc: lkml <linux-kernel@vger.kernel.org>,
	"Daniel Vetter" <daniel@ffwll.ch>,
	"Christian Koenig" <christian.koenig@amd.com>,
	"Sumit Semwal" <sumit.semwal@linaro.org>,
	"Liam Mark" <lmark@codeaurora.org>,
	"Chris Goldsworthy" <cgoldswo@codeaurora.org>,
	"Laura Abbott" <labbott@kernel.org>,
	"Brian Starkey" <Brian.Starkey@arm.com>,
	"Hridya Valsaraju" <hridya@google.com>,
	"Suren Baghdasaryan" <surenb@google.com>,
	"Sandeep Patil" <sspatil@google.com>,
	"Daniel Mentz" <danielmentz@google.com>,
	"Ørjan Eide" <orjan.eide@arm.com>,
	"Robin Murphy" <robin.murphy@arm.com>,
	"Simon Ser" <contact@emersion.fr>,
	"James Jones" <jajones@nvidia.com>,
	"Leo Yan" <leo.yan@linaro.org>,
	linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org
Subject: Re: [PATCH] dma-buf: system_heap: Avoid warning on mid-order allocations
Date: Tue, 14 Sep 2021 15:56:37 +0200	[thread overview]
Message-ID: <YUCqFfalhgSTX249@phenom.ffwll.local> (raw)
In-Reply-To: <20210909023741.2592429-1-john.stultz@linaro.org>

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@ffwll.ch>
> Cc: Christian Koenig <christian.koenig@amd.com>
> Cc: Sumit Semwal <sumit.semwal@linaro.org>
> Cc: Liam Mark <lmark@codeaurora.org>
> Cc: Chris Goldsworthy <cgoldswo@codeaurora.org>
> Cc: Laura Abbott <labbott@kernel.org>
> Cc: Brian Starkey <Brian.Starkey@arm.com>
> Cc: Hridya Valsaraju <hridya@google.com>
> Cc: Suren Baghdasaryan <surenb@google.com>
> Cc: Sandeep Patil <sspatil@google.com>
> Cc: Daniel Mentz <danielmentz@google.com>
> Cc: Ørjan Eide <orjan.eide@arm.com>
> Cc: Robin Murphy <robin.murphy@arm.com>
> Cc: Simon Ser <contact@emersion.fr>
> Cc: James Jones <jajones@nvidia.com>
> Cc: Leo Yan <leo.yan@linaro.org>
> Cc: linux-media@vger.kernel.org
> Cc: dri-devel@lists.freedesktop.org
> Signed-off-by: John Stultz <john.stultz@linaro.org>

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

> ---
>  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