Messages in this thread | | | Date | Mon, 27 Oct 2008 12:57:00 +0100 | From | Jens Axboe <> | Subject | Re: [PATCH 2/2] x86: replace BIO_VMERGE_BOUNDARY with BIOVEC_PHYS_MERGEABLE |
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On Mon, Oct 27 2008, Jeremy Fitzhardinge wrote: > Jens Axboe wrote: > >Pretty much baffles me as well, xen should just need to do > > > >#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) 0 > > > > It needs to be a runtime switch, since we only want to do this when > actually running under Xen. Also, its possible that the two pages might > actually be physically contiguous, so they could be merged anyway.
Alright, then add a xen_biovec_phys_mergeable(vec1, vec2) in the xen code that actually checks this for real. You can add your switch there as well. Then put the BIOVEC_PHYS_MERGEABLE() in the xen arch includes, done.
What Tomo is saying is that this has nothing to do with virtual merging, and he's right.
-- Jens Axboe
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