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 7F4EB6B003D for ; Fri, 8 May 2009 07:47:21 -0400 (EDT) Date: Fri, 8 May 2009 13:47:42 +0200 From: Ingo Molnar Subject: Re: [PATCH 4/8] proc: export more page flags in /proc/kpageflags Message-ID: <20090508114742.GB17129@elte.hu> References: <20090508105320.316173813@intel.com> <20090508111031.020574236@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090508111031.020574236@intel.com> Sender: owner-linux-mm@kvack.org To: Wu Fengguang , =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker , Steven Rostedt , Peter Zijlstra , Li Zefan Cc: Andrew Morton , LKML , KOSAKI Motohiro , Andi Kleen , Matt Mackall , Alexey Dobriyan , linux-mm@kvack.org List-ID: * Wu Fengguang wrote: > Export all page flags faithfully in /proc/kpageflags. Ongoing objection and NAK against extended haphazard exporting of kernel internals via an ad-hoc ABI via ad-hoc, privatized instrumentation that only helps the MM code and nothing else. It was a mistake to introduce the /proc/kpageflags hack a year ago, and it even more wrong today to expand on it. /proc/kpageflags should be done via the proper methods outlined in the previous mails i wrote on this topic: for example by using the 'object collections' abstraction i suggested. Clean enumeration of all pages (files, tasks, etc.) and the definition of histograms over it via free-form filter expressions is the right way to do this. It would not only help other subsystems, it would also be far more capable. So this should be done in cooperation with instrumentation folks, while improving _all_ of Linux instrumentation in general. Or, if you dont have the time/interest to work with us on that, it should not be done at all. Not having the resources/interest to do something properly is not a license to introduce further instrumentation crap into Linux. Ingo -- 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