Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760289Ab3DBFFs (ORCPT ); Tue, 2 Apr 2013 01:05:48 -0400 Received: from mail-oa0-f47.google.com ([209.85.219.47]:45558 "EHLO mail-oa0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759884Ab3DBFFq (ORCPT ); Tue, 2 Apr 2013 01:05:46 -0400 MIME-Version: 1.0 In-Reply-To: <1364847069-2887-2-git-send-email-nzimmer@sgi.com> References: <5159C147.70800@sgi.com> <1364847069-2887-1-git-send-email-nzimmer@sgi.com> <1364847069-2887-2-git-send-email-nzimmer@sgi.com> Date: Tue, 2 Apr 2013 10:35:46 +0530 Message-ID: Subject: Re: [PATCH v6 1/2] cpufreq: split the cpufreq_driver_lock and use the rcu From: Viresh Kumar To: Nathan Zimmer Cc: rjw@sisk.pl, cpufreq@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 839 Lines: 19 On 2 April 2013 01:41, Nathan Zimmer wrote: > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c > +static struct cpufreq_driver __rcu *cpufreq_driver; > +static DEFINE_SPINLOCK(cpufreq_driver_lock); You really need this lock? This is only used in cpufreq_register_driver and unregister_driver... And it doesn't protect other routines at all. And because we are using rcu stuff now, probably this lock is just not required. > +static DEFINE_SPINLOCK(cpufreq_data_lock); Only this one is required and it can be the rwlock which is already pushed by rafael. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/