Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757138AbZD1LhR (ORCPT ); Tue, 28 Apr 2009 07:37:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754961AbZD1LhE (ORCPT ); Tue, 28 Apr 2009 07:37:04 -0400 Received: from mga03.intel.com ([143.182.124.21]:24754 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752976AbZD1LhD (ORCPT ); Tue, 28 Apr 2009 07:37:03 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.40,260,1239001200"; d="scan'208";a="136743187" Date: Tue, 28 Apr 2009 19:36:16 +0800 From: Wu Fengguang To: Ingo Molnar Cc: KOSAKI Motohiro , Pekka Enberg , Andi Kleen , Steven Rostedt , =?utf-8?B?RnLpppjpp7tpYw==?= Weisbecker , Larry Woodman , Peter Zijlstra , Eduard - Gabriel Munteanu , Andrew Morton , LKML , Matt Mackall , Alexey Dobriyan , "linux-mm@kvack.org" Subject: Re: [PATCH 5/5] proc: export more page flags in /proc/kpageflags Message-ID: <20090428113616.GA22439@localhost> References: <84144f020904280219p197d5ceag846ae9a80a76884e@mail.gmail.com> <20090428092918.GC21085@elte.hu> <20090428183237.EBDE.A69D9226@jp.fujitsu.com> <20090428093833.GE21085@elte.hu> <20090428095551.GB21168@localhost> <20090428110553.GD25347@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090428110553.GD25347@elte.hu> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1492 Lines: 37 On Tue, Apr 28, 2009 at 07:05:53PM +0800, Ingo Molnar wrote: > > * Wu Fengguang wrote: > > > > See my other mail i just sent: it would be a natural extension > > > of tracing to also dump all current object state when tracing is > > > turned on. That way no drop_caches is needed at all. > > > > I can understand the merits here - I also did readahead > > tracing/accounting in _one_ piece of code. Very handy. > > > > The readahead traces are now raw printks - converting to the > > ftrace framework would be a big win. > > > > But. It's still not a fit-all solution. Imagine when full data > > _since_ booting is required, but the user cannot afford a reboot. > > The above 'get object state' interface (which allows passive > sampling) - integrated into the tracing framework - would serve that > goal, agreed? Agreed. That could in theory a good complement to dynamic tracings. Then what will be the canonical form for all the 'get object state' interfaces - "object.attr=value", or whatever? I'm afraid we will have to sacrifice efficiency or human readability to have a normalized form. Or to define two standard forms? One "key value" form and one "value1 value2 value3..." form? Thanks, Fengguang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/