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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, 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 C76CECA9ECB for ; Fri, 18 Oct 2019 05:55:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9416520820 for ; Fri, 18 Oct 2019 05:55:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="sjRzD+Gd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2442084AbfJRFzQ (ORCPT ); Fri, 18 Oct 2019 01:55:16 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:52746 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727328AbfJRFzQ (ORCPT ); Fri, 18 Oct 2019 01:55:16 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x9I3ieGR179119; Fri, 18 Oct 2019 03:46:04 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id; s=corp-2019-08-05; bh=oEQUIfo7AVvAUyWjcHqWo9vpZdzmoQJUFPQ9HRPDZF8=; b=sjRzD+GdAvTM5ClBJPlb4ur6Zax2NB8Zecn2BqrVLxi/WyAyGnRJHVCgDhJql+wrZN9S ywtcpKpl7K4BCmlHtmfaoK/em1SnnR0B3whJjkCpcMQDNwsRH9InJBQ88YpL0qSJbe1B SS29WhQDZo2OnIPiK1lF2221GAEWORJvPV+kPZmknEZ9S35FRzeoGCkRDTIQM+4U+tFX VMp/wsyHWXy2fMODbyCpEOXgpqP1KXBGwvgka8TQvQHimpafuO7dchq75BkaG5vTFWZ8 D0C1ZHf6PRivow8Wa2JCZtlErrxxAFyikuXv5L+CpljwTCaWaZkoQBoUM9eTfq2RqIVq Pg== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by aserp2120.oracle.com with ESMTP id 2vq0q412t4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 18 Oct 2019 03:46:04 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x9I3hpff069398; Fri, 18 Oct 2019 03:46:03 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userp3020.oracle.com with ESMTP id 2vq0evbatx-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 18 Oct 2019 03:46:03 +0000 Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x9I3jvLR003616; Fri, 18 Oct 2019 03:45:58 GMT Received: from z2.cn.oracle.com (/10.182.70.159) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 18 Oct 2019 03:45:57 +0000 From: Zhenzhong Duan To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, tim.c.chen@linux.intel.com, Zhenzhong Duan , Thomas Gleixner , Borislav Petkov , Ingo Molnar , "H. Peter Anvin" , Boris Ostrovsky Subject: [PATCH] x86: Don't use MWAIT if explicitly requested Date: Fri, 18 Oct 2019 11:45:54 +0800 Message-Id: <1571370354-17736-1-git-send-email-zhenzhong.duan@oracle.com> X-Mailer: git-send-email 1.8.3.1 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9413 signatures=668684 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910180035 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9413 signatures=668684 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910180035 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If 'idle=nomwait' is specified or process matching what's in processor_idle_dmi_table, we should't use MWAIT at bootup stage before cpuidle driver loaded, even if it's preferred by default on Intel. Add a check so that HALT instruction is used in those cases. Signed-off-by: Zhenzhong Duan Cc: Thomas Gleixner Cc: Borislav Petkov Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Boris Ostrovsky --- arch/x86/kernel/process.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 5e94c43..37fc577 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -667,6 +667,10 @@ static void amd_e400_idle(void) */ static int prefer_mwait_c1_over_halt(const struct cpuinfo_x86 *c) { + /* Don't use MWAIT-C1 if explicitly requested */ + if (boot_option_idle_override == IDLE_NOMWAIT) + return 0; + if (c->x86_vendor != X86_VENDOR_INTEL) return 0; -- 1.8.3.1