From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id 6A68E8D0030 for ; Fri, 29 Oct 2010 09:03:51 -0400 (EDT) Received: by iwn38 with SMTP id 38so2828364iwn.14 for ; Fri, 29 Oct 2010 06:03:50 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <4CCABEA0.8080909@redhat.com> References: <1288200090-23554-1-git-send-email-yinghan@google.com> <4CC869F5.2070405@redhat.com> <20101028091158.4de545e9.kamezawa.hiroyu@jp.fujitsu.com> <20101029114529.4d3a8b9c.kamezawa.hiroyu@jp.fujitsu.com> <4CCA42D0.5090603@redhat.com> <4CCABEA0.8080909@redhat.com> Date: Fri, 29 Oct 2010 22:03:50 +0900 Message-ID: Subject: Re: [PATCH] mm: don't flush TLB when propagate PTE access bit to struct page. From: Minchan Kim Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org To: Rik van Riel Cc: KAMEZAWA Hiroyuki , Ken Chen , Ying Han , Hugh Dickins , Nick Piggin , linux-mm@kvack.org, Andrew Morton List-ID: On Fri, Oct 29, 2010 at 9:31 PM, Rik van Riel wrote: > On 10/29/2010 12:27 AM, Minchan Kim wrote: > >> What happens if we don't flush TLB? >> It will make for old page to pretend young page. >> If it is, how does it affect reclaim? > > Other way around - it will make a young page pretend to be an > old page, because the TLB won't know it needs to flush the > Accessed bit into the page tables (where the bit was recently > cleared). Ying's patch just removes TLB flush when page access bit is changed from young to old. We still flush TLB flush when from old to young change by ptep_set_access_flags. Do I miss something? -- Kind regards, Minchan Kim -- 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