From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753093AbbJFTdR (ORCPT ); Tue, 6 Oct 2015 15:33:17 -0400 Received: from e32.co.us.ibm.com ([32.97.110.150]:33887 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752313AbbJFTdQ (ORCPT ); Tue, 6 Oct 2015 15:33:16 -0400 X-IBM-Helo: d03dlp01.boulder.ibm.com X-IBM-MailFrom: paulmck@linux.vnet.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org Date: Tue, 6 Oct 2015 12:33:11 -0700 From: "Paul E. McKenney" To: Oleg Nesterov Cc: Josh Triplett , linux-kernel@vger.kernel.org, mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, dvhart@linux.intel.com, fweisbec@gmail.com, bobby.prani@gmail.com Subject: Re: [PATCH tip/core/rcu 0/13] percpu-rwsem patches for 4.4 Message-ID: <20151006193311.GS3910@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20151006164514.GA15516@linux.vnet.ibm.com> <20151006174226.GK9600@cloud> <20151006185055.GA15844@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151006185055.GA15844@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15100619-0005-0000-0000-000018BE6C73 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 06, 2015 at 08:50:56PM +0200, Oleg Nesterov wrote: > On 10/06, Josh Triplett wrote: > > > > For all 13: > > Reviewed-by: Josh Triplett > > Thanks! > > > Regarding the rcu_sync infrastructure: odd that an atomic read > > on the reader proves ligher weight than > > rcu_read_lock()/rcu_read_unlock(). > > Cough... Could you spell? ;) I am just curious and I can't understand > what do you mean. I would guess that Josh is thinking of CONFIG_PREEMPT=n and that you worked with CONFIG_PREEMPT=y. But it would be good to get this fully understood. Thanx, Paul