From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754776AbYIWTrP (ORCPT ); Tue, 23 Sep 2008 15:47:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751714AbYIWTq7 (ORCPT ); Tue, 23 Sep 2008 15:46:59 -0400 Received: from gir.skynet.ie ([193.1.99.77]:46657 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750928AbYIWTq6 (ORCPT ); Tue, 23 Sep 2008 15:46:58 -0400 Date: Tue, 23 Sep 2008 20:46:56 +0100 From: Mel Gorman To: KOSAKI Motohiro Cc: Dave Hansen , LKML , Linux-MM Subject: Re: [PATCH 1/2] Report the pagesize backing a VMA in /proc/pid/smaps Message-ID: <20080923194655.GA25542@csn.ul.ie> References: <20080922162152.GB7716@csn.ul.ie> <1222102098.8533.62.camel@nimitz> <20080923211140.DC16.KOSAKI.MOTOHIRO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20080923211140.DC16.KOSAKI.MOTOHIRO@jp.fujitsu.com> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (23/09/08 21:15), KOSAKI Motohiro didst pronounce: > > > The corollary is that someone running with a 64K base page kernel may be > > > surprised that the pagesize is always 4K. However I'll check if there is > > > a simple way of checking out if the MMU size differs from PAGE_SIZE. > > > > Sure. If it isn't easy, the best thing to do is probably just to > > document the "interesting" behavior. > > Dave, please let me know getpagesize() function return to 4k or 64k on ppc64. > I think the PageSize line of the /proc/pid/smap and getpagesize() result should be matched. > > otherwise, enduser may be confused. > To distinguish between the two, I now report the kernel pagesize and the mmu pagesize like so KernelPageSize: 64 kB MMUPageSize: 4 kB This is running a kernel with a 64K base pagesize on a PPC970MP which does not support 64K hardware pagesizes. Does this make sense? -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab