From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E3C3AECDE4B for ; Thu, 8 Nov 2018 16:12:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A28D920818 for ; Thu, 8 Nov 2018 16:12:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A28D920818 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727573AbeKIBso (ORCPT ); Thu, 8 Nov 2018 20:48:44 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:40638 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726963AbeKIBso (ORCPT ); Thu, 8 Nov 2018 20:48:44 -0500 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id wA8GBYpm143711 for ; Thu, 8 Nov 2018 11:12:32 -0500 Received: from e14.ny.us.ibm.com (e14.ny.us.ibm.com [129.33.205.204]) by mx0a-001b2d01.pphosted.com with ESMTP id 2nmpm9dh76-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 08 Nov 2018 11:12:31 -0500 Received: from localhost by e14.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 8 Nov 2018 16:12:26 -0000 Received: from b01ledav003.gho.pok.ibm.com (b01ledav003.gho.pok.ibm.com [9.57.199.108]) by b01cxnp22036.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id wA8GCPjJ32112818 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 8 Nov 2018 16:12:25 GMT Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BB4B3B206B; Thu, 8 Nov 2018 16:12:25 +0000 (GMT) Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9E374B2065; Thu, 8 Nov 2018 16:12:25 +0000 (GMT) Received: from paulmck-ThinkPad-W541 (unknown [9.85.145.141]) by b01ledav003.gho.pok.ibm.com (Postfix) with ESMTP; Thu, 8 Nov 2018 16:12:25 +0000 (GMT) Received: by paulmck-ThinkPad-W541 (Postfix, from userid 1000) id 48F8516C17E8; Thu, 8 Nov 2018 08:12:25 -0800 (PST) Date: Thu, 8 Nov 2018 08:12:25 -0800 From: "Paul E. McKenney" To: Sebastian Andrzej Siewior Cc: lcapitulino@redhat.com, julia@ni.com, linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: rcu: enable rcu_normal_after_boot by default for RT Reply-To: paulmck@linux.ibm.com References: <20181101230235.GA8757@linux.ibm.com> <20181108155225.d2m6sx5z7tvzurft@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181108155225.d2m6sx5z7tvzurft@linutronix.de> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 18110816-0052-0000-0000-00000352B518 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00010008; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000269; SDB=6.01114512; UDB=6.00577828; IPR=6.00894611; MB=3.00024076; MTD=3.00000008; XFM=3.00000015; UTC=2018-11-08 16:12:28 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18110816-0053-0000-0000-00005EB2E57C Message-Id: <20181108161225.GK4170@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-11-08_08:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1811080136 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 08, 2018 at 04:52:26PM +0100, Sebastian Andrzej Siewior wrote: > On 2018-11-01 16:02:35 [-0700], Paul E. McKenney wrote: > > > The forcing of an expedited grace period is an expensive and very > > > RT-application unfriendly operation, as it forcibly preempts all running > > > tasks on CPUs which are preventing the gp from expiring. > > > > > > By default, as a policy decision, disable the expediting of grace > > > periods (after boot) on configurations which enable PREEMPT_RT_FULL. > > > > > > Suggested-by: Luiz Capitulino > > > Signed-off-by: Julia Cartwright > > > Signed-off-by: Sebastian Andrzej Siewior > > > > In case it matters: > > > > Acked-by: Paul E. McKenney > > > > Alternatively, any reason that I should not pull this into -rcu? > because we don't have CONFIG_PREEMPT_RT_FULL yet. Fair enough. This particular case works without CONFIG_PREEMPT_RT_FULL defined, but up to you guys. Thanx, Paul