From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx167.postini.com [74.125.245.167]) by kanga.kvack.org (Postfix) with SMTP id 76A1C6B0037 for ; Wed, 24 Jul 2013 14:52:59 -0400 (EDT) Received: by mail-la0-f49.google.com with SMTP id ea20so611788lab.22 for ; Wed, 24 Jul 2013 11:52:57 -0700 (PDT) Date: Wed, 24 Jul 2013 22:52:56 +0400 From: Cyrill Gorcunov Subject: Re: [PATCH] mm: Save soft-dirty bits on swapped pages Message-ID: <20130724185256.GA24365@moon> References: <20130724160826.GD24851@moon> <20130724163734.GE24851@moon> <20130724171728.GH8508@moon> <1374687373.7382.22.camel@dabdike> <20130724181516.GI8508@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: James Bottomley , Linux MM , LKML , Pavel Emelyanov , Andrew Morton , Matt Mackall , Xiao Guangrong , Marcelo Tosatti , KOSAKI Motohiro , Stephen Rothwell On Wed, Jul 24, 2013 at 11:21:46AM -0700, Andy Lutomirski wrote: > > > > I fear for tracking soft-dirty-bit for swapped entries we sinply have > > no other place than pte (still i'm quite open for ideas, maybe there > > are a better way which I've missed). > > I know approximately nothing about how swap and anon_vma work. > > For files, sticking it in struct page seems potentially nicer, > although finding a free bit might be tough. (FWIW, I have plans to > free up a page flag on x86 some time moderately soon as part of a > completely unrelated project.) I think this stuff really belongs to > the address_space more than it belongs to the pte. Well, some part of information already lays in pte (such as 'file' bit, swap entries) so it looks natural i think to work on this level. but letme think if use page struct for that be more convenient... > > How do you handle the write syscall? I fear I somehow miss your point here, could please alaborate a bit? There is no additional code I know of being write() specific, just a code for #PF exceptions. -- 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