Re: [RFC][PATCH 00/26] sched/numa

Avi Kivity
2012-03-20T11:49:33Z

On 03/20/2012 01:07 PM, Peter Zijlstra wrote:
> On Tue, 2012-03-20 at 12:52 +0200, Avi Kivity wrote:
>
> > You use the dma engine for eager copying, not on demand.
>
> Sure, but during that time no access to that entire vma is allowed, so
> you have to unmap it, and any fault in there will have to wait for the
> entire copy to complete.
>
> Or am I misunderstanding how things would work?

Option 1: write-protect the area you are migrating, on write fault allow
write access and discard the migration target (marking the page for
migration later)

Option 2: clear the dirty bits on the area you are migrating, after
migration completes examine the dirty bit, and if dirty, discard the
migration target.

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error compiling committee.c: too many arguments to function