From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754880Ab0IORmG (ORCPT ); Wed, 15 Sep 2010 13:42:06 -0400 Received: from e8.ny.us.ibm.com ([32.97.182.138]:43086 "EHLO e8.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754048Ab0IORmF (ORCPT ); Wed, 15 Sep 2010 13:42:05 -0400 Date: Wed, 15 Sep 2010 23:11:58 +0530 From: Balbir Singh To: Richard Guenther Cc: Nikanth Karthikesan , KOSAKI Motohiro , linux-mm@kvack.org, Andrew Morton , Michael Matz , Matt Mackall , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] After swapout/swapin private dirty mappings are reported clean in smaps Message-ID: <20100915174157.GA22371@balbir.in.ibm.com> Reply-To: balbir@linux.vnet.ibm.com References: <20100915134724.C9EE.A69D9226@jp.fujitsu.com> <201009151034.22497.knikanth@suse.de> <20100915141710.C9F7.A69D9226@jp.fujitsu.com> <201009151201.11359.knikanth@suse.de> <20100915140911.GC4383@balbir.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-12-10) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Richard Guenther [2010-09-15 16:14:17]: > On Wed, 15 Sep 2010, Balbir Singh wrote: > > > * Nikanth Karthikesan [2010-09-15 12:01:11]: > > > > > How? Current smaps information without this patch provides incorrect > > > information. Just because a private dirty page became part of swap cache, it > > > shown as clean and backed by a file. If it is shown as clean and backed by > > > swap then it is fine. > > > > > > > How is GDB using this information? > > GDB counts the number of dirty and swapped pages in a private mapping and > based on that decides whether it needs to dump it to a core file or not. > If there are no dirty or swapped pages gdb assumes it can reconstruct > the mapping from the original backing file. This way for example > shared libraries do not end up in the core file. > Thanks for clarifying -- Three Cheers, Balbir From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id BF6526B007D for ; Wed, 15 Sep 2010 13:42:04 -0400 (EDT) Received: from d01relay05.pok.ibm.com (d01relay05.pok.ibm.com [9.56.227.237]) by e2.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id o8FHRFFX030850 for ; Wed, 15 Sep 2010 13:27:15 -0400 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay05.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o8FHg2bD118916 for ; Wed, 15 Sep 2010 13:42:02 -0400 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id o8FHg1EN010525 for ; Wed, 15 Sep 2010 13:42:01 -0400 Date: Wed, 15 Sep 2010 23:11:58 +0530 From: Balbir Singh Subject: Re: [PATCH v2] After swapout/swapin private dirty mappings are reported clean in smaps Message-ID: <20100915174157.GA22371@balbir.in.ibm.com> Reply-To: balbir@linux.vnet.ibm.com References: <20100915134724.C9EE.A69D9226@jp.fujitsu.com> <201009151034.22497.knikanth@suse.de> <20100915141710.C9F7.A69D9226@jp.fujitsu.com> <201009151201.11359.knikanth@suse.de> <20100915140911.GC4383@balbir.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org To: Richard Guenther Cc: Nikanth Karthikesan , KOSAKI Motohiro , linux-mm@kvack.org, Andrew Morton , Michael Matz , Matt Mackall , linux-kernel@vger.kernel.org List-ID: * Richard Guenther [2010-09-15 16:14:17]: > On Wed, 15 Sep 2010, Balbir Singh wrote: > > > * Nikanth Karthikesan [2010-09-15 12:01:11]: > > > > > How? Current smaps information without this patch provides incorrect > > > information. Just because a private dirty page became part of swap cache, it > > > shown as clean and backed by a file. If it is shown as clean and backed by > > > swap then it is fine. > > > > > > > How is GDB using this information? > > GDB counts the number of dirty and swapped pages in a private mapping and > based on that decides whether it needs to dump it to a core file or not. > If there are no dirty or swapped pages gdb assumes it can reconstruct > the mapping from the original backing file. This way for example > shared libraries do not end up in the core file. > Thanks for clarifying -- Three Cheers, Balbir -- 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