Jean Guyader
2010-Nov-15 17:59 UTC
[Xen-devel] [PATCH 0/3] iommu: Introduce range operation
Hi, This patches series add a range operation for the intel iommu. IOTLBs flushes can be really expensive on some hardware, so we need a range interface to only do the flush once, instead of for each pages. 01: intel_iommu_set_entry 02: iommu_export_set_entry 03: xc_iommu_map_batch Thanks, Jean _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2010-Nov-18 12:36 UTC
Re: [Xen-devel] [PATCH 0/3] iommu: Introduce range operation
On 15/11/2010 17:59, "Jean Guyader" <jean.guyader@eu.citrix.com> wrote:> Hi, > > This patches series add a range operation for the intel iommu. > > IOTLBs flushes can be really expensive on some hardware, so we > need a range interface to only do the flush once, instead of for > each pages.I''m going to have a go at TLB flush batching for IOMMUs by extending the existing TLB clock algorithm. Hopefully it will avoid need for guest interface changes. The tradeoff will be that flushes, when they happen, will be full address space rather than a range flush. But there should be vastly fewer of them. Nonetheless I may make old vs new flush behaviour switchable via a boot parameter for a while. -- Keir> 01: intel_iommu_set_entry > 02: iommu_export_set_entry > 03: xc_iommu_map_batch > > Thanks, > Jean > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel