From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755506Ab1ETWm7 (ORCPT ); Fri, 20 May 2011 18:42:59 -0400 Received: from e1.ny.us.ibm.com ([32.97.182.141]:46284 "EHLO e1.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751254Ab1ETWmx (ORCPT ); Fri, 20 May 2011 18:42:53 -0400 Date: Fri, 20 May 2011 15:42:50 -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, linux-tip-commits@vger.kernel.org Subject: Re: [tip:core/rcu] Revert "rcu: Decrease memory-barrier usage based on semi-formal proof" Message-ID: <20110520224250.GL2366@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <4DD6D746.6070107@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4DD6D746.6070107@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 02:04:06PM -0700, Yinghai Lu wrote: > On 05/19/2011 02:37 PM, tip-bot for Paul E. McKenney wrote: > > Commit-ID: 80d02085d99039b3b7f3a73c8896226b0cb1ba07 > > Gitweb: http://git.kernel.org/tip/80d02085d99039b3b7f3a73c8896226b0cb1ba07 > > Author: Paul E. McKenney > > AuthorDate: Thu, 12 May 2011 01:08:07 -0700 > > Committer: Ingo Molnar > > CommitDate: Thu, 19 May 2011 23:25:29 +0200 > > > > Revert "rcu: Decrease memory-barrier usage based on semi-formal proof" > > > > This reverts commit e59fb3120becfb36b22ddb8bd27d065d3cdca499. > > > > This reversion was due to (extreme) boot-time slowdowns on SPARC seen by > > Yinghai Lu and on x86 by Ingo > > . > > This is a non-trivial reversion due to intervening commits. > > > > Conflicts: > > > > Documentation/RCU/trace.txt > > kernel/rcutree.c > > > > Signed-off-by: Ingo Molnar > > --- > > Documentation/RCU/trace.txt | 17 ++++-- > > kernel/rcutree.c | 130 ++++++++++++++++++++++++------------------ > > kernel/rcutree.h | 9 ++- > > kernel/rcutree_plugin.h | 7 +- > > kernel/rcutree_trace.c | 12 ++-- > > 5 files changed, 102 insertions(+), 73 deletions(-) > > > > current tip/master that have this reverting and without setting DEBUG_LOCKING_API_SELFTESTS > > still get delay > > [ 35.419453] cpu_dev_init done > [ 128.981770] memory_dev_init done > > should take only 3 or 4 seconds. Thank you for checking this out. This is with the same configuration you sent earlier? (Other than the DEBUG_LOCKING_API_SELFTESTS, of course.) Thanx, Paul