From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1753021AbcERMCx (ORCPT <rfc822;w@1wt.eu>);
	Wed, 18 May 2016 08:02:53 -0400
Received: from mout.kundenserver.de ([212.227.126.131]:61110 "EHLO
	mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1752967AbcERMCv convert rfc822-to-8bit (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Wed, 18 May 2016 08:02:51 -0400
From: Arnd Bergmann <arnd@arndb.de>
To: paulmck@linux.vnet.ibm.com
Cc: Mark Rutland <mark.rutland@arm.com>, catalin.marinas@arm.com,
        dennis.chen@arm.com, jiangshanlai@gmail.com, josh@joshtriplett.org,
        linux-kernel@vger.kernel.org, mathieu.desnoyers@efficios.com,
        rostedt@goodmis.org, steve.capper@arm.com, will.deacon@arm.com
Subject: Re: [PATCHv2] rcu: tree: correctly handle sparse possible CPUs
Date: Wed, 18 May 2016 14:02:36 +0200
Message-ID: <2685335.QWam4BCxRS@wuerfel>
User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; )
In-Reply-To: <20160518001251.GA13330@linux.vnet.ibm.com>
References: <20160516191947.GH3528@linux.vnet.ibm.com> <20160517190106.GJ3528@linux.vnet.ibm.com> <20160518001251.GA13330@linux.vnet.ibm.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8BIT
Content-Type: text/plain; charset="utf-8"
X-Provags-ID: V03:K0:oGb7cr1pXIxxI2YLBo7W5NQQaQC7nlVEWFIx5Dne3Y3cUSsEqd/
 MVR80+xsYOLkg77BBNszxe/ArrBeKRy0bVKk/4+I40b4zGOL2Vb8DUkF22efj7vFAhRKZx+
 mEHiggIW4+949LRolXBs5oC1teC2rlgJHGNOZCHXIkoVGKOuLJ/pB4zncgyLX7A2SJB8US3
 AYrns7v+ooALtXC1cMnTQ==
X-UI-Out-Filterresults: notjunk:1;V01:K0:YI3paZlMANA=:zITW/tlKupkNrVF1lFDOch
 JnlktOg3gzbAQzR24zpfkiyakroix8/7sFXqZw3sdLvS+CGg50hzkLhygQ94aKSzVx+/SBcIa
 XaKhSLt+OUEeeuvl1ads7RsEN4NsIIgcsseyIlFIKNtiaWX1XRW/UBjfL1oX1ZOMmhd0yNatr
 +hILeB3jxIx3TiFsI1K852GYoe3o6UAX0YF1Fq+HhNtOxlzlHGxxWzKf3G6keYecij2k2SRL5
 xjcql32EvKOnC1CBofn4iTvUzAH+f1peCg6dPyue+j+LQjKxOTEAunTAb4WyMaXTavSDE7Foi
 0Z8XzjPR5PGFDDNdyCW0XcO4RbH4XCyfg8K9yWmL/E7/49gCtsokn9jnr3Ghiv/drjftg2pyR
 dThvBSYRhiSm6e3DDnfuI7a2Z0TOiq6MxvoI7xOHR8QxCuAgvUNZgRvVJAuB9PeuDiOSBk6CU
 bVr65Kd9dkhEU99hcyChNwD8Aj6fpI85ruIpinCqBkJe4HGaA6wNgGv+5DaIuFZmGQWBFI6EF
 czlrsiVC/lSA9phslWwo5CSZlQkUZVjgXTsJY0gW8I+FuKk8hofW+orX3XRevHZSkAcvxvoqm
 qQPjPxY26uf/iJ/A4G9J/yD/3sa1xSTS50DCOGIU7rWgzo7/3EW2a9oKIAe74ODurIWTDpmTI
 krcQi9sptckWr5m43M7pFL3AIz85jfJFCGB3WJG8aUDGfihrJk7DwMGCc6WsrS99S2u3P1b0x
 nwNcyyLgNvULsdCSJbSRZUFWrOBcYSm11OGRkg==
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tuesday 17 May 2016 17:12:51 Paul E. McKenney wrote:
> And some build errors:
> 
> In file included from /home/paulmck/public_git/linux-rcu/kernel/rcu/tree.c:4209:0:
> /home/paulmck/public_git/linux-rcu/kernel/rcu/tree_plugin.h: In function ‘rcu_boost_kthread_setaffinity’:
> /home/paulmck/public_git/linux-rcu/kernel/rcu/tree_plugin.h:1168:2: error: implicit declaration of function ‘for_each_leaf_node_cpu_bit’ [-Werror=implicit-function-declaration]
>   for_each_leaf_node_cpu_bit(rnp, cpu, bit)
>   ^
> /home/paulmck/public_git/linux-rcu/kernel/rcu/tree_plugin.h:1169:3: error: expected ‘;’ before ‘if’
>    if ((mask & bit) && cpu != outgoingcpu)
>    ^
> /home/paulmck/public_git/linux-rcu/kernel/rcu/tree_plugin.h:1159:16: warning: unused variable ‘mask’ [-Wunused-variable]
>   unsigned long mask = rcu_rnp_online_cpus(rnp);
>                 ^
> 
> Please see below for the .config.
> 
> I have dropped the patch from my tree, looking forward to getting an
> update that fixes the build errors.
> 

It's the missing "possible_" that Mark mentioned in his reply on Friday.

Please fold the fixup below into the patch if you want to get it to build.

Signed-off-by: Arnd Bergmann <arnd@arndb.de

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index fd6b0f701bed..bb137b0ef6f3 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1165,7 +1165,7 @@ static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
 		return;
 	if (!zalloc_cpumask_var(&cm, GFP_KERNEL))
 		return;
-	for_each_leaf_node_cpu_bit(rnp, cpu, bit)
+	for_each_leaf_node_possible_cpu_bit(rnp, cpu, bit)
 		if ((mask & bit) && cpu != outgoingcpu)
 			cpumask_set_cpu(cpu, cm);
 	if (cpumask_weight(cm) == 0)