From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932757AbdDRTun (ORCPT ); Tue, 18 Apr 2017 15:50:43 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:53076 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932640AbdDRTug (ORCPT ); Tue, 18 Apr 2017 15:50:36 -0400 Message-Id: <20170418170553.191578891@linutronix.de> User-Agent: quilt/0.63-1 Date: Tue, 18 Apr 2017 19:04:52 +0200 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Steven Rostedt , Sebastian Siewior , x86@kernel.org, Fenghua Yu Subject: [patch V2 10/24] perf/x86/intel/cqm: Use cpuhp_setup_state_cpuslocked() References: <20170418170442.665445272@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=perfx86intelcqm_Use_cpuhp_setup_state_locked.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sebastian Andrzej Siewior intel_cqm_init() holds get_online_cpus() while registerring the hotplug callbacks. cpuhp_setup_state() 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_cpuslocked() to avoid the nested call. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Cc: Peter Zijlstra Cc: x86@kernel.org Cc: Fenghua Yu --- arch/x86/events/intel/cqm.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/arch/x86/events/intel/cqm.c +++ b/arch/x86/events/intel/cqm.c @@ -1746,12 +1746,12 @@ static int __init intel_cqm_init(void) * Setup the hot cpu notifier once we are sure cqm * is enabled to avoid notifier leak. */ - cpuhp_setup_state(CPUHP_AP_PERF_X86_CQM_STARTING, - "perf/x86/cqm:starting", - intel_cqm_cpu_starting, NULL); - cpuhp_setup_state(CPUHP_AP_PERF_X86_CQM_ONLINE, "perf/x86/cqm:online", - NULL, intel_cqm_cpu_exit); - + cpuhp_setup_state_cpuslocked(CPUHP_AP_PERF_X86_CQM_STARTING, + "perf/x86/cqm:starting", + intel_cqm_cpu_starting, NULL); + cpuhp_setup_state_cpuslocked(CPUHP_AP_PERF_X86_CQM_ONLINE, + "perf/x86/cqm:online", + NULL, intel_cqm_cpu_exit); out: put_online_cpus();