From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967100AbdEZIn6 (ORCPT ); Fri, 26 May 2017 04:43:58 -0400 Received: from terminus.zytor.com ([65.50.211.136]:52693 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422861AbdEZInz (ORCPT ); Fri, 26 May 2017 04:43:55 -0400 Date: Fri, 26 May 2017 01:40:02 -0700 From: tip-bot for Sebastian Andrzej Siewior Message-ID: Cc: mpe@ellerman.id.au, bigeasy@linutronix.de, paulmck@linux.vnet.ibm.com, hpa@zytor.com, benh@kernel.crashing.org, rostedt@goodmis.org, mingo@kernel.org, peterz@infradead.org, linux-kernel@vger.kernel.org, tglx@linutronix.de Reply-To: mpe@ellerman.id.au, bigeasy@linutronix.de, paulmck@linux.vnet.ibm.com, hpa@zytor.com, benh@kernel.crashing.org, rostedt@goodmis.org, mingo@kernel.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, peterz@infradead.org In-Reply-To: <20170524081548.331016542@linutronix.de> References: <20170524081548.331016542@linutronix.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:smp/hotplug] powerpc/powernv: Use stop_machine_cpuslocked() Git-Commit-ID: f9a69931c3959940538884d5962b770c3db75df5 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: f9a69931c3959940538884d5962b770c3db75df5 Gitweb: http://git.kernel.org/tip/f9a69931c3959940538884d5962b770c3db75df5 Author: Sebastian Andrzej Siewior AuthorDate: Wed, 24 May 2017 10:15:27 +0200 Committer: Thomas Gleixner CommitDate: Fri, 26 May 2017 10:10:41 +0200 powerpc/powernv: Use stop_machine_cpuslocked() set_subcores_per_core() holds get_online_cpus() while invoking stop_machine(). stop_machine() invokes get_online_cpus() as well. This is correct, but prevents the conversion of the hotplug locking to a percpu rwsem. Use stop_machine_cpuslocked() to avoid the nested call. Convert *_online_cpus() to the new interfaces while at it. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Acked-by: Ingo Molnar Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Benjamin Herrenschmidt Cc: Steven Rostedt Cc: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20170524081548.331016542@linutronix.de --- arch/powerpc/platforms/powernv/subcore.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/platforms/powernv/subcore.c b/arch/powerpc/platforms/powernv/subcore.c index 0babef1..e6230f10 100644 --- a/arch/powerpc/platforms/powernv/subcore.c +++ b/arch/powerpc/platforms/powernv/subcore.c @@ -348,7 +348,7 @@ static int set_subcores_per_core(int new_mode) state->master = 0; } - get_online_cpus(); + cpus_read_lock(); /* This cpu will update the globals before exiting stop machine */ this_cpu_ptr(&split_state)->master = 1; @@ -356,9 +356,10 @@ static int set_subcores_per_core(int new_mode) /* Ensure state is consistent before we call the other cpus */ mb(); - stop_machine(cpu_update_split_mode, &new_mode, cpu_online_mask); + stop_machine_cpuslocked(cpu_update_split_mode, &new_mode, + cpu_online_mask); - put_online_cpus(); + cpus_read_unlock(); return 0; }