From patchwork Sat Apr 15 17:01:13 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 9682283 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5261460388 for ; Sat, 15 Apr 2017 17:31:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4524528173 for ; Sat, 15 Apr 2017 17:31:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 39FA128395; Sat, 15 Apr 2017 17:31:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9DCAE28358 for ; Sat, 15 Apr 2017 17:31:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755154AbdDORbV (ORCPT ); Sat, 15 Apr 2017 13:31:21 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:44470 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754641AbdDORbO (ORCPT ); Sat, 15 Apr 2017 13:31:14 -0400 Received: from localhost ([127.0.0.1] helo=[127.0.1.1]) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1czRWJ-00083d-5R; Sat, 15 Apr 2017 19:29:59 +0200 Message-Id: <20170415171651.746595672@linutronix.de> User-Agent: quilt/0.63-1 Date: Sat, 15 Apr 2017 19:01:13 +0200 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Steven Rostedt , Sebastian Siewior , "Rafael J. Wysocki" , Viresh Kumar , linux-pm@vger.kernel.org Subject: [patch 06/20] cpufreq: Use cpuhp_setup_state_nocalls_locked() References: <20170415170107.643253702@linutronix.de> MIME-Version: 1.0 Content-Disposition: inline; filename=cpufreq-Use-cpuhp_setup_state_nocalls_locked.patch Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Sebastian Andrzej Siewior cpufreq holds get_online_cpus() while invoking cpuhp_setup_state_nocalls() to make subsys_interface_register() and the registration of hotplug calls atomic versus cpu hotplug. cpuhp_setup_state_nocalls() invokes get_online_cpus() as well. This is correct, but prevents the conversion of the hotplug locking to a percpu rwsem. Use cpuhp_setup_state_nocalls_locked() to avoid the nested call. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Cc: "Rafael J. Wysocki" Cc: Viresh Kumar Cc: linux-pm@vger.kernel.org Acked-by: Rafael J. Wysocki Acked-by: Viresh Kumar --- drivers/cpufreq/cpufreq.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -2473,9 +2473,10 @@ int cpufreq_register_driver(struct cpufr goto err_if_unreg; } - ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "cpufreq:online", - cpuhp_cpufreq_online, - cpuhp_cpufreq_offline); + ret = cpuhp_setup_state_nocalls_locked(CPUHP_AP_ONLINE_DYN, + "cpufreq:online", + cpuhp_cpufreq_online, + cpuhp_cpufreq_offline); if (ret < 0) goto err_if_unreg; hp_online = ret; @@ -2519,7 +2520,7 @@ int cpufreq_unregister_driver(struct cpu get_online_cpus(); subsys_interface_unregister(&cpufreq_interface); remove_boost_sysfs_file(); - cpuhp_remove_state_nocalls(hp_online); + cpuhp_remove_state_nocalls_locked(hp_online); write_lock_irqsave(&cpufreq_driver_lock, flags);