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=-16.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 810C5C64E8A for ; Wed, 2 Dec 2020 05:08:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 211C120DD4 for ; Wed, 2 Dec 2020 05:08:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726526AbgLBFIi (ORCPT ); Wed, 2 Dec 2020 00:08:38 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:5616 "EHLO mx0b-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725902AbgLBFIi (ORCPT ); Wed, 2 Dec 2020 00:08:38 -0500 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0B253HiV160294; Wed, 2 Dec 2020 00:07:48 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=NhBkZp36oxCYwRu/2a8TCp40Ymb+nr0f31x0dnD0PJ0=; b=L+K938fnrcZOxFRGeuDY2Ym0FtXBIaTXmhlSAnOngQGoub3OrNwI7VNUCTTaixbRaimU RVVzldso3s//lNZgvJBczk1cRLGiexzEnIvpHx9ftm4TWYViHHkRO0gROoAd9KFJpstg zFmASctrZAfg+Hz3w3yqto/8gkTQ0m+/JPgfGMw3FpUxbSe6cBWahRC+WIJbhbnK/AFm Rl3+jaQAgp3eFAcJ687Tzqa40/1cBz5HRMaxsP5P9ek/wKAuWWROOFiG6TJOgy+9RHHx F5OFLcFzoNUv2ZqeYIykyZtcMS93CaRgvwl7wq+Vev6DLX01Vlct86HdclLBxT9tp5ji Nw== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 355y6cq39p-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 02 Dec 2020 00:07:45 -0500 Received: from m0098417.ppops.net (m0098417.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 0B253K1e160646; Wed, 2 Dec 2020 00:07:45 -0500 Received: from ppma03fra.de.ibm.com (6b.4a.5195.ip4.static.sl-reverse.com [149.81.74.107]) by mx0a-001b2d01.pphosted.com with ESMTP id 355y6cq396-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 02 Dec 2020 00:07:45 -0500 Received: from pps.filterd (ppma03fra.de.ibm.com [127.0.0.1]) by ppma03fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 0B252u2b023935; Wed, 2 Dec 2020 05:07:43 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma03fra.de.ibm.com with ESMTP id 353e685pdd-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 02 Dec 2020 05:07:43 +0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 0B255ANo12059380 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 2 Dec 2020 05:05:10 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BAC384C04A; Wed, 2 Dec 2020 05:05:10 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 385C94C044; Wed, 2 Dec 2020 05:05:08 +0000 (GMT) Received: from saptagiri.in.ibm.com (unknown [9.85.125.1]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Wed, 2 Dec 2020 05:05:08 +0000 (GMT) From: Srikar Dronamraju To: Michael Ellerman Cc: linuxppc-dev , Srikar Dronamraju , LKML , Nicholas Piggin , Nathan Lynch , Gautham R Shenoy , Peter Zijlstra , Valentin Schneider , Juri Lelli , Waiman Long , Phil Auld Subject: [PATCH v2 3/4] powerpc: Reintroduce is_kvm_guest in a new avatar Date: Wed, 2 Dec 2020 10:34:55 +0530 Message-Id: <20201202050456.164005-4-srikar@linux.vnet.ibm.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201202050456.164005-1-srikar@linux.vnet.ibm.com> References: <20201202050456.164005-1-srikar@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.312,18.0.737 definitions=2020-12-01_12:2020-11-30,2020-12-01 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 mlxlogscore=969 mlxscore=0 suspectscore=0 priorityscore=1501 clxscore=1015 adultscore=0 lowpriorityscore=0 malwarescore=0 impostorscore=0 spamscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2012020031 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Introduce a static branch that would be set during boot if the OS happens to be a KVM guest. Subsequent checks to see if we are on KVM will rely on this static branch. This static branch would be used in vcpu_is_preempted in a subsequent patch. Cc: linuxppc-dev Cc: LKML Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Nathan Lynch Cc: Gautham R Shenoy Cc: Peter Zijlstra Cc: Valentin Schneider Cc: Juri Lelli Cc: Waiman Long Cc: Phil Auld Acked-by: Waiman Long Signed-off-by: Srikar Dronamraju --- arch/powerpc/include/asm/kvm_guest.h | 10 ++++++++++ arch/powerpc/include/asm/kvm_para.h | 2 +- arch/powerpc/kernel/firmware.c | 2 ++ 3 files changed, 13 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/kvm_guest.h b/arch/powerpc/include/asm/kvm_guest.h index ba8291e02ba9..627ba272e781 100644 --- a/arch/powerpc/include/asm/kvm_guest.h +++ b/arch/powerpc/include/asm/kvm_guest.h @@ -7,8 +7,18 @@ #define __POWERPC_KVM_GUEST_H__ #if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_KVM_GUEST) +#include + +DECLARE_STATIC_KEY_FALSE(kvm_guest); + +static inline bool is_kvm_guest(void) +{ + return static_branch_unlikely(&kvm_guest); +} + bool check_kvm_guest(void); #else +static inline bool is_kvm_guest(void) { return false; } static inline bool check_kvm_guest(void) { return false; } #endif diff --git a/arch/powerpc/include/asm/kvm_para.h b/arch/powerpc/include/asm/kvm_para.h index 6fba06b6cfdb..abe1b5e82547 100644 --- a/arch/powerpc/include/asm/kvm_para.h +++ b/arch/powerpc/include/asm/kvm_para.h @@ -14,7 +14,7 @@ static inline int kvm_para_available(void) { - return IS_ENABLED(CONFIG_KVM_GUEST) && check_kvm_guest(); + return IS_ENABLED(CONFIG_KVM_GUEST) && is_kvm_guest(); } static inline unsigned int kvm_arch_para_features(void) diff --git a/arch/powerpc/kernel/firmware.c b/arch/powerpc/kernel/firmware.c index 0aeb6a5b1a9e..28498fc573f2 100644 --- a/arch/powerpc/kernel/firmware.c +++ b/arch/powerpc/kernel/firmware.c @@ -22,6 +22,7 @@ EXPORT_SYMBOL_GPL(powerpc_firmware_features); #endif #if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_KVM_GUEST) +DEFINE_STATIC_KEY_FALSE(kvm_guest); bool check_kvm_guest(void) { struct device_node *hyper_node; @@ -33,6 +34,7 @@ bool check_kvm_guest(void) if (!of_device_is_compatible(hyper_node, "linux,kvm")) return 0; + static_branch_enable(&kvm_guest); return 1; } #endif -- 2.18.4