From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755102Ab2IFNfr (ORCPT ); Thu, 6 Sep 2012 09:35:47 -0400 Received: from merlin.infradead.org ([205.233.59.134]:34890 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752810Ab2IFNfo convert rfc822-to-8bit (ORCPT ); Thu, 6 Sep 2012 09:35:44 -0400 Message-ID: <1346938478.18408.4.camel@twins> Subject: Re: [PATCH tip/core/rcu 03/23] rcu: Move RCU grace-period cleanup into kthread From: Peter Zijlstra To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, josh@joshtriplett.org, niv@us.ibm.com, tglx@linutronix.de, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, eric.dumazet@gmail.com, darren@dvhart.com, fweisbec@gmail.com, sbw@mit.edu, patches@linaro.org Date: Thu, 06 Sep 2012 15:34:38 +0200 In-Reply-To: <1346350718-30937-3-git-send-email-paulmck@linux.vnet.ibm.com> References: <20120830181811.GA29154@linux.vnet.ibm.com> <1346350718-30937-1-git-send-email-paulmck@linux.vnet.ibm.com> <1346350718-30937-3-git-send-email-paulmck@linux.vnet.ibm.com> Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Mailer: Evolution 3.2.2- Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2012-08-30 at 11:18 -0700, Paul E. McKenney wrote: > static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags) > __releases(rcu_get_root(rsp)->lock) > { > + raw_spin_unlock_irqrestore(&rcu_get_root(rsp)->lock, flags); > + wake_up(&rsp->gp_wq); /* Memory barrier implied by wake_up() path. */ > } Could you now also clean up the locking so that the caller releases this lock? I so dislike asymmetric locking like that..