From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757360AbaHHQtj (ORCPT ); Fri, 8 Aug 2014 12:49:39 -0400 Received: from cdptpa-outbound-snat.email.rr.com ([107.14.166.229]:10450 "EHLO cdptpa-oedge-vip.email.rr.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757315AbaHHQte (ORCPT ); Fri, 8 Aug 2014 12:49:34 -0400 Date: Fri, 8 Aug 2014 12:49:31 -0400 From: Steven Rostedt To: "Paul E. McKenney" Cc: Peter Zijlstra , Oleg Nesterov , linux-kernel@vger.kernel.org, mingo@kernel.org, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, dhowells@redhat.com, edumazet@google.com, dvhart@linux.intel.com, fweisbec@gmail.com, bobby.prani@gmail.com, masami.hiramatsu.pt@hitachi.com Subject: Re: [PATCH v3 tip/core/rcu 3/9] rcu: Add synchronous grace-period waiting for RCU-tasks Message-ID: <20140808124931.07c3b78a@gandalf.local.home> In-Reply-To: <20140808163905.GA5821@linux.vnet.ibm.com> References: <20140807184635.GI3588@twins.programming.kicks-ass.net> <20140807154907.6f59cf6e@gandalf.local.home> <20140807155326.18481e66@gandalf.local.home> <20140807200813.GB3935@laptop> <20140807171823.1a481290@gandalf.local.home> <20140808064020.GZ9918@twins.programming.kicks-ass.net> <20140808101221.21056900@gandalf.local.home> <20140808143413.GB9918@twins.programming.kicks-ass.net> <20140808105858.171da847@gandalf.local.home> <20140808162714.GG9918@twins.programming.kicks-ass.net> <20140808163905.GA5821@linux.vnet.ibm.com> X-Mailer: Claws Mail 3.10.1 (GTK+ 2.24.24; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-RR-Connecting-IP: 107.14.168.118:25 X-Cloudmark-Score: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 8 Aug 2014 09:39:05 -0700 "Paul E. McKenney" wrote: > Unless this is done in idle, at which point RCU-sched is studiously > ignoring any preempt_disable() sections. ftrace doesn't use synchronize_sched() today because of this. It instead just does a "schedule_on_each_cpu()" and waits for that to return before going further. -- Steve