From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755107AbbJHJBs (ORCPT ); Thu, 8 Oct 2015 05:01:48 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:48669 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753816AbbJHJBq (ORCPT ); Thu, 8 Oct 2015 05:01:46 -0400 Date: Thu, 8 Oct 2015 11:01:28 +0200 From: Peter Zijlstra To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, dvhart@linux.intel.com, fweisbec@gmail.com, oleg@redhat.com, bobby.prani@gmail.com Subject: Re: [PATCH tip/core/rcu 18/18] rcu: Better hotplug handling for synchronize_sched_expedited() Message-ID: <20151008090128.GI3604@twins.programming.kicks-ass.net> References: <20151006162907.GA12020@linux.vnet.ibm.com> <1444148977-14108-1-git-send-email-paulmck@linux.vnet.ibm.com> <1444148977-14108-18-git-send-email-paulmck@linux.vnet.ibm.com> <20151007142627.GE3604@twins.programming.kicks-ass.net> <20151007162653.GP3910@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151007162653.GP3910@linux.vnet.ibm.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 07, 2015 at 09:26:53AM -0700, Paul E. McKenney wrote: > On Wed, Oct 07, 2015 at 04:26:27PM +0200, Peter Zijlstra wrote: > Indeed, that approach looks better than moving rcu_note_context_switch(), > which probably results in deadlocks. I will update my patch accordingly. Yeah, calling rcu_note_context_switch() under the rq->lock is asking for trouble we don't need. Thanks!