Re: [PATCH] x86: use __GFP_NORETRY in the case of GFP_DMA with pci-nommu

[Joerg Roedel <joerg.roedel@amd.com>]

On Fri, Sep 05, 2008 at 05:58:48PM +0900, FUJITA Tomonori wrote:
> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> ---
>  arch/x86/kernel/pci-nommu.c |    3 +++
>  1 files changed, 3 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/x86/kernel/pci-nommu.c b/arch/x86/kernel/pci-nommu.c
> index 526b2db..3495f88 100644
> --- a/arch/x86/kernel/pci-nommu.c
> +++ b/arch/x86/kernel/pci-nommu.c
> @@ -102,6 +102,9 @@ nommu_alloc_coherent(struct device *hwdev, size_t size,
>  	if (dma_mask == DMA_24BIT_MASK)
>  		gfp |= GFP_DMA;
>  again:
> +	if (gfp & GFP_DMA)
> +		gfp |= __GFP_NORETRY;
> +

Huh? Why that? The __GFP_NORETRY is a hint from the caller to the page
allocator on how aggressive it should try to allocate memory. I don't
think the DMA code should touch those flags unless there is a very very
good reason for it.

>  	page = alloc_pages_node(node, gfp, get_order(size));
>  	if (!page)
>  		return NULL;
> -- 
> 1.5.4.2
> 
> 

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