From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752540Ab2KRBdK (ORCPT ); Sat, 17 Nov 2012 20:33:10 -0500 Received: from e7.ny.us.ibm.com ([32.97.182.137]:54908 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752501Ab2KRBdI (ORCPT ); Sat, 17 Nov 2012 20:33:08 -0500 Date: Fri, 16 Nov 2012 11:26:25 -0800 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, edumazet@google.com, darren@dvhart.com, fweisbec@gmail.com, sbw@mit.edu, patches@linaro.org Subject: [PATCH tip/core/rcu] Fix TINY_RCU rcu_is_cpu_rrupt_from_idle check Message-ID: <20121116192625.GA447@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12111801-5806-0000-0000-00001BE64661 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The rcu_is_cpu_rrupt_from_idle() needs to allow for one interrupt level from the idle loop, but TINY_RCU checks for a call from the idle loop itself. This commit fixes this issue. Reported-by: Josh Triplett Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney b/kernel/rcutiny.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c index e4c6a59..e7dce58 100644 --- a/kernel/rcutiny.c +++ b/kernel/rcutiny.c @@ -195,7 +195,7 @@ EXPORT_SYMBOL(rcu_is_cpu_idle); */ int rcu_is_cpu_rrupt_from_idle(void) { - return rcu_dynticks_nesting <= 0; + return rcu_dynticks_nesting <= 1; } /*