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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 BA22DC43331 for ; Thu, 26 Mar 2020 20:41:13 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E49822070A for ; Thu, 26 Mar 2020 20:41:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E49822070A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48pH2C6h1RzDqtK for ; Fri, 27 Mar 2020 07:41:07 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=leonardo@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 48pGzc5dt4zDqD3 for ; Fri, 27 Mar 2020 07:38:52 +1100 (AEDT) Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 02QKWO9Q008292; Thu, 26 Mar 2020 16:38:39 -0400 Received: from ppma04wdc.us.ibm.com (1a.90.2fa9.ip4.static.sl-reverse.com [169.47.144.26]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ywewx5wjs-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 26 Mar 2020 16:38:39 -0400 Received: from pps.filterd (ppma04wdc.us.ibm.com [127.0.0.1]) by ppma04wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 02QKbqpA012173; Thu, 26 Mar 2020 20:38:39 GMT Received: from b01cxnp22035.gho.pok.ibm.com (b01cxnp22035.gho.pok.ibm.com [9.57.198.25]) by ppma04wdc.us.ibm.com with ESMTP id 2ywaw9cjsm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 26 Mar 2020 20:38:39 +0000 Received: from b01ledav006.gho.pok.ibm.com (b01ledav006.gho.pok.ibm.com [9.57.199.111]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 02QKccO954329848 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 26 Mar 2020 20:38:38 GMT Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id AE881AC05E; Thu, 26 Mar 2020 20:38:38 +0000 (GMT) Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5CCFFAC059; Thu, 26 Mar 2020 20:38:26 +0000 (GMT) Received: from LeoBras.aus.stglabs.ibm.com (unknown [9.85.162.45]) by b01ledav006.gho.pok.ibm.com (Postfix) with ESMTP; Thu, 26 Mar 2020 20:38:25 +0000 (GMT) From: Leonardo Bras To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Leonardo Bras , Allison Randal , Greg Kroah-Hartman , Thomas Gleixner Subject: [RFC PATCH 1/1] ppc/smp: Replace unnecessary 'while' by 'if' Date: Thu, 26 Mar 2020 17:37:52 -0300 Message-Id: <20200326203752.497029-1-leonardo@linux.ibm.com> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.645 definitions=2020-03-26_11:2020-03-26, 2020-03-26 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 suspectscore=0 spamscore=0 clxscore=1015 malwarescore=0 impostorscore=0 bulkscore=0 phishscore=0 mlxscore=0 adultscore=0 mlxlogscore=660 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003260146 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" spin_until_cond() will wait until nmi_ipi_busy == false, and nmi_ipi_lock_start() does not seem to change nmi_ipi_busy, so there is no way this while will ever repeat. Replace this 'while' by an 'if', so it does not look like it can repeat. Signed-off-by: Leonardo Bras --- arch/powerpc/kernel/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index ea6adbf6a221..7c904d6fb4d2 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -473,7 +473,7 @@ static int __smp_send_nmi_ipi(int cpu, void (*fn)(struct pt_regs *), return 0; nmi_ipi_lock_start(&flags); - while (nmi_ipi_busy) { + if (nmi_ipi_busy) { nmi_ipi_unlock_end(&flags); spin_until_cond(!nmi_ipi_busy); nmi_ipi_lock_start(&flags); -- 2.24.1