From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <48D2EBBB.205@goop.org> Date: Thu, 18 Sep 2008 17:00:59 -0700 From: Jeremy Fitzhardinge MIME-Version: 1.0 Subject: Re: Populating multiple ptes at fault time References: <48D142B2.3040607@goop.org> <48D17E75.80807@redhat.com> <48D1851B.70703@goop.org> <48D18919.9060808@redhat.com> <48D18C6B.5010407@goop.org> <48D2B970.7040903@redhat.com> <48D2D3B2.10503@goop.org> <48D2E65A.6020004@redhat.com> In-Reply-To: <48D2E65A.6020004@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Avi Kivity Cc: Nick Piggin , Hugh Dickens , Linux Memory Management List , Linux Kernel Mailing List , Avi Kivity , Andrew Morton , Rik van Riel , Marcelo Tosatti List-ID: Avi Kivity wrote: >> Yes. At worst Linux would underestimate the process RSS a bit >> (depending on how many unsynchronized ptes you leave lying around). I >> > > Not the RSS (that's pte.present pages) but the working set (aka active > list). Yep. >> bet there's an appropriate pvop hook you could use to force >> synchronization just before the kernel actually inspects the bits >> (leaving lazy mode sounds good). >> > > It would have to be a new lazy mode, not the existing one, I think. The only direct use of pte_young() is in zap_pte_range, within a mmu_lazy region. So syncing the A bit state on entering lazy mmu mode would work fine there. The call via page_referenced_one() doesn't seem to have a very convenient hook though. Perhaps putting something in page_check_address() would do the job. J -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org