From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx140.postini.com [74.125.245.140]) by kanga.kvack.org (Postfix) with SMTP id 448406B0031 for ; Wed, 24 Jul 2013 13:17:32 -0400 (EDT) Received: by mail-la0-f49.google.com with SMTP id ea20so532369lab.22 for ; Wed, 24 Jul 2013 10:17:30 -0700 (PDT) Date: Wed, 24 Jul 2013 21:17:28 +0400 From: Cyrill Gorcunov Subject: Re: [PATCH] mm: Save soft-dirty bits on swapped pages Message-ID: <20130724171728.GH8508@moon> References: <20130724160826.GD24851@moon> <20130724163734.GE24851@moon> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Andy Lutomirski Cc: Linux MM , LKML , Pavel Emelyanov , Andrew Morton , Matt Mackall , Xiao Guangrong , Marcelo Tosatti , KOSAKI Motohiro , Stephen Rothwell On Wed, Jul 24, 2013 at 10:06:53AM -0700, Andy Lutomirski wrote: > > Hi Andy, if I understand you correctly "file-backed pages" are carried > > in pte with _PAGE_FILE bit set and the swap soft-dirty bit won't be > > used on them but _PAGE_SOFT_DIRTY will be set on write if only I've > > not missed something obvious (Pavel?). > > If I understand this stuff correctly, the vmscan code calls > try_to_unmap when it reclaims memory, which makes its way into > try_to_unmap_one, which clears the pte (and loses the soft-dirty bit). Indeed, I was so stareing into swap that forgot about files. I'll do a separate patch for that, thanks! -- 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