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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,UNPARSEABLE_RELAY,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 6A280C43441 for ; Thu, 29 Nov 2018 14:45:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2EC3E20673 for ; Thu, 29 Nov 2018 14:45:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="IBYLD9zM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2EC3E20673 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.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 S2387907AbeK3Buq (ORCPT ); Thu, 29 Nov 2018 20:50:46 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:59060 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728759AbeK3Buq (ORCPT ); Thu, 29 Nov 2018 20:50:46 -0500 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id wATEi5mR047297; Thu, 29 Nov 2018 14:44:36 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2018-07-02; bh=F92bRlEb61Q3pwcRtc6+V2AqdzNg8d7Uy6KvtZg0aT4=; b=IBYLD9zMit8lt6sLhwR2dcnfP4RC+9MvrhPu/Ijsd0ebbzfBCfosYCurJSgypxXTogTz TJ6HMke6uKtUrTJFvWcPIJB8i8BaO38FfMQnxQk10ttT3YfbARGfS1fClilDGRpfkRIb kuSac3g2d7BCmVBAjpTbhn/h4GvjmMrJu2TDI03QjCUgqS+UnTNaz7coQLhGd65YuVar h3WGeDpCUMkbUS1corbpGM2pb3SJ2Z9xL3mJKHPLX8iEPMWyqEn8FhO35mQgekR7we6o JRl4He404VUKImcxTcfjAXSKxasHB5XJdu5UU8U4Abdp1fwrTJpYWAc9L71QANU066on xg== Received: from userv0021.oracle.com (userv0021.oracle.com [156.151.31.71]) by userp2120.oracle.com with ESMTP id 2nxy9rghtf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 29 Nov 2018 14:44:36 +0000 Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userv0021.oracle.com (8.14.4/8.14.4) with ESMTP id wATEia8t017338 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 29 Nov 2018 14:44:36 GMT Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id wATEiZbL009560; Thu, 29 Nov 2018 14:44:35 GMT Received: from char.us.oracle.com (/10.152.32.25) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 29 Nov 2018 06:44:34 -0800 Received: by char.us.oracle.com (Postfix, from userid 1000) id E9AA26A00FB; Thu, 29 Nov 2018 09:44:30 -0500 (EST) Date: Thu, 29 Nov 2018 09:44:30 -0500 From: Konrad Rzeszutek Wilk To: Thomas Gleixner Cc: LKML , x86@kernel.org, Peter Zijlstra , Andy Lutomirski , Linus Torvalds , Jiri Kosina , Tom Lendacky , Josh Poimboeuf , Andrea Arcangeli , David Woodhouse , Tim Chen , Andi Kleen , Dave Hansen , Casey Schaufler , Asit Mallick , Arjan van de Ven , Jon Masters , Waiman Long , Greg KH , Dave Stewart , Kees Cook Subject: Re: [patch V2 10/28] sched/smt: Expose sched_smt_present static key Message-ID: <20181129144430.GK32259@char.us.oracle.com> References: <20181125183328.318175777@linutronix.de> <20181125185004.430168326@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181125185004.430168326@linutronix.de> User-Agent: Mutt/1.8.3 (2017-05-23) X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9091 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1811290124 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Nov 25, 2018 at 07:33:38PM +0100, Thomas Gleixner wrote: > Make the scheduler's 'sched_smt_present' static key globaly available, so > it can be used in the x86 speculation control code. > > Provide a query function and a stub for the CONFIG_SMP=n case. > > Signed-off-by: Thomas Gleixner Reviewed-by: Konrad Rzeszutek Wilk > --- > > v1 -> v2: Move SMT stuff to separate header. Unbreaks ia64 build > > --- > include/linux/sched/smt.h | 18 ++++++++++++++++++ > kernel/sched/sched.h | 4 +--- > 2 files changed, 19 insertions(+), 3 deletions(-) > > --- /dev/null > +++ b/include/linux/sched/smt.h > @@ -0,0 +1,18 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +#ifndef _LINUX_SCHED_SMT_H > +#define _LINUX_SCHED_SMT_H > + > +#include > + > +#ifdef CONFIG_SCHED_SMT > +extern struct static_key_false sched_smt_present; > + > +static __always_inline bool sched_smt_active(void) > +{ > + return static_branch_likely(&sched_smt_present); > +} > +#else > +static inline bool sched_smt_active(void) { return false; } > +#endif > + > +#endif > --- a/kernel/sched/sched.h > +++ b/kernel/sched/sched.h > @@ -23,6 +23,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -936,9 +937,6 @@ static inline int cpu_of(struct rq *rq) > > > #ifdef CONFIG_SCHED_SMT > - > -extern struct static_key_false sched_smt_present; > - > extern void __update_idle_core(struct rq *rq); > > static inline void update_idle_core(struct rq *rq) > >