Re: [PATCH 03/23] AMD IOMMU: implement lazy IO/TLB flushing

From: Muli Ben-Yehuda
Date: Sun Sep 21 2008 - 01:35:54 EST


On Fri, Sep 19, 2008 at 07:43:39PM +0200, Joerg Roedel wrote:
> Hi All,
>
> FUJITA mentioned that I forgot to discuss this patch with you guys, the
> implementers and maintainers for Intel VT-d and Calgary IOMMU drivers. I
> would like to hear your opinion on that patch. He is right with that.
> The patch is already in tip/iommu but can easily be reverted if there
> are fundamental objections.
> The patch basically moves the iommu=fullflush and iommu=nofullflush
> option from the GART code to pci-dma.c. So we can use these parameters
> in other IOMMU implementations too. Since Intel VT-d is implementing
> also lazy IO/TLB flushing it would benefit from this generic parameter
> too. I am not so sure about Calgary, but we have other parameters for
> iommu= which doesn't affect all hardware IOMMUs.

Calgary can't use fullflush, but in general the more unified our IOMMU
options, the better for the users. It's a pain to have to remember
which option applies to which IOMMU implementation.

Cheers,
Muli
--
Workshop on I/O Virtualization (WIOV '08)
Co-located with OSDI '08, Dec 2008, San Diego, CA
http://www.usenix.org/wiov08
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/