From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id 51D496B003D for ; Wed, 29 Apr 2009 15:14:25 -0400 (EDT) Subject: Re: [PATCH 5/5] proc: export more page flags in /proc/kpageflags From: Matt Mackall 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 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Andrew Morton , LKML , KOSAKI Motohiro , Andi Kleen , Alexey Dobriyan , "linux-mm@kvack.org" List-ID: 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, 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