Re: [PATCH] x86: avoid unnecessary low zone allocation in AMD IOMMU's alloc_coherent

FUJITA Tomonori
2008-09-11T13:37:36Z

On Thu, 11 Sep 2008 11:10:00 +0200
Joerg Roedel <joerg.roedel@amd.com> wrote:

> On Wed, Sep 10, 2008 at 11:45:34PM +0900, FUJITA Tomonori wrote:
> > On Wed, 10 Sep 2008 16:38:18 +0200
> > Joerg Roedel <joro@8bytes.org> wrote:
> > > Ok, thats a valid point. I queue your patch with the AMD IOMMU updates
> > > for 2.6.28. Thanks.
> >
> > Ingo already has queued it his tree, I think.
>
> I asked Ingo to remove it from his tree to avoid merge conflicts with
> updates I am currently preparing. Here is the patch I queued into my
> 2.6.28 update chain.
>
> Joerg
>
> ===
> commit 42a7fa8d8a7f1680cba76e4824dba30bfd1c9d70
> Author: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> Date: Wed Sep 10 20:19:40 2008 +0900
>
> x86: avoid unnecessary low zone allocation in AMD IOMMU's alloc_coherent
>
> x86's common alloc_coherent (dma_alloc_coherent in dma-mapping.h) sets
> up the gfp flag according to the device dma_mask but AMD IOMMU doesn't
> need it for devices that the IOMMU can do virtual mappings for. This
> patch avoids unnecessary low zone allocation.
>
> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
>
> diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
> index ae38b24..09261dc 100644
> --- a/arch/x86/kernel/amd_iommu.c
> +++ b/arch/x86/kernel/amd_iommu.c

I see, thanks.