Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758804AbZD2TPo (ORCPT ); Wed, 29 Apr 2009 15:15:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757749AbZD2TP2 (ORCPT ); Wed, 29 Apr 2009 15:15:28 -0400 Received: from waste.org ([66.93.16.53]:34083 "EHLO waste.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755861AbZD2TP1 (ORCPT ); Wed, 29 Apr 2009 15:15:27 -0400 Subject: Re: [PATCH 5/5] proc: export more page flags in /proc/kpageflags From: Matt Mackall To: Wu Fengguang Cc: Andrew Morton , LKML , KOSAKI Motohiro , Andi Kleen , Alexey Dobriyan , "linux-mm@kvack.org" In-Reply-To: <20090429080553.GA14838@localhost> References: <20090428010907.912554629@intel.com> <20090428014920.769723618@intel.com> <1240940961.938.451.camel@calx> <20090429080553.GA14838@localhost> Content-Type: text/plain Date: Wed, 29 Apr 2009 14:13:56 -0500 Message-Id: <1241032436.938.1519.camel@calx> Mime-Version: 1.0 X-Mailer: Evolution 2.24.5 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1713 Lines: 46 On Wed, 2009-04-29 at 16:05 +0800, Wu Fengguang wrote: > On Wed, Apr 29, 2009 at 01:49:21AM +0800, Matt Mackall wrote: > > On Tue, 2009-04-28 at 09:09 +0800, Wu Fengguang wrote: > > > plain text document attachment (kpageflags-extending.patch) > > > Export 9 page flags in /proc/kpageflags, and 8 more for kernel developers. > > > > My only concern with this patch is it knows a bit too much about SLUB > > internals (and perhaps not enough about SLOB, which also overloads > > flags). > > Yup. PG_private=PG_slob_free is not masked because SLOB actually does > not set PG_slab at all. I wonder if it's safe to do this change: > > /* SLOB */ > - PG_slob_page = PG_active, > + PG_slob_page = PG_slab, > PG_slob_free = PG_private, Yep. > In the page-types output: > > flags page-count MB symbolic-flags long-symbolic-flags > 0x000800000040 7113 27 ______A_________________P____ active,private > 0x000000000040 66 0 ______A______________________ active > > The above two lines are obviously for SLOB pages. It indicates lots of > free SLOB pages. So my question is: Free here just means partially allocated. > - Do you have other means to get the nr_free_slobs info? (I found none in the code) > or > - Will exporting the SL*B overloaded flags going to help? Yes, it's useful. -- http://selenic.com : development and support for Mercurial and Linux -- 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/