From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754752Ab1EUNSs (ORCPT ); Sat, 21 May 2011 09:18:48 -0400 Received: from e7.ny.us.ibm.com ([32.97.182.137]:55540 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751437Ab1EUNSr (ORCPT ); Sat, 21 May 2011 09:18:47 -0400 Date: Sat, 21 May 2011 06:18:44 -0700 From: "Paul E. McKenney" To: Yinghai Lu Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, hpa@zytor.com, tglx@linutronix.de, mingo@elte.hu Subject: Re: [tip:core/rcu] Revert "rcu: Decrease memory-barrier usage based on semi-formal proof" Message-ID: <20110521131844.GE2271@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <4DD6D746.6070107@kernel.org> <20110520224250.GL2366@linux.vnet.ibm.com> <4DD6F4A2.1070401@kernel.org> <20110520231428.GN2366@linux.vnet.ibm.com> <4DD6F64C.3030402@kernel.org> <20110520234923.GQ2366@linux.vnet.ibm.com> <4DD70120.9090801@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4DD70120.9090801@kernel.org> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 20, 2011 at 05:02:40PM -0700, Yinghai Lu wrote: > On 05/20/2011 04:49 PM, Paul E. McKenney wrote: > > On Fri, May 20, 2011 at 04:16:28PM -0700, Yinghai Lu wrote: > ... > >> > >> the same one i sent out before, but let DEBUG_LOCKING_API_SELFTESTS disabled. > > > > OK, just to make sure I understand... You are compiling exactly the > > same kernel source tree with exactly the same .config, just with two > > different versions of gcc, correct? > yes. > > > > If so, it is quite possible that the slow one is the correct one. :-/ > yeah, new version always have problem. > > looks like opensuse11.3 has 4.5.0 and fedora14 has 4.5.1 OK, so fedora14 is the fast one (4.5.1) and opensuse11.3 is the slow one (4.5.0), correct? Thanx, Paul