From patchwork Wed Aug 17 03:43:06 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cyril Bur X-Patchwork-Id: 659874 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3sDZs55y8Sz9t1F for ; Wed, 17 Aug 2016 13:46:17 +1000 (AEST) Received: from ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 3sDZs54g1QzDr6r for ; Wed, 17 Aug 2016 13:46:17 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 3sDZpV6ppRzDr4g for ; Wed, 17 Aug 2016 13:44:02 +1000 (AEST) Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u7H3i0wl051589 for ; Tue, 16 Aug 2016 23:44:00 -0400 Received: from e23smtp04.au.ibm.com (e23smtp04.au.ibm.com [202.81.31.146]) by mx0a-001b2d01.pphosted.com with ESMTP id 24v3dgnyd3-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 16 Aug 2016 23:43:59 -0400 Received: from localhost by e23smtp04.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Wed, 17 Aug 2016 13:43:52 +1000 X-IBM-Helo: d23dlp03.au.ibm.com X-IBM-MailFrom: cyrilbur@gmail.com X-IBM-RcptTo: linuxppc-dev@lists.ozlabs.org Received: from d23relay08.au.ibm.com (d23relay08.au.ibm.com [9.185.71.33]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id 9F8683578056 for ; Wed, 17 Aug 2016 13:43:51 +1000 (EST) Received: from d23av01.au.ibm.com (d23av01.au.ibm.com [9.190.234.96]) by d23relay08.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u7H3hpES29622320 for ; Wed, 17 Aug 2016 13:43:51 +1000 Received: from d23av01.au.ibm.com (localhost [127.0.0.1]) by d23av01.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u7H3hpfP032596 for ; Wed, 17 Aug 2016 13:43:51 +1000 Received: from ozlabs.au.ibm.com (ozlabs.au.ibm.com [9.192.253.14]) by d23av01.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id u7H3hpl9032589; Wed, 17 Aug 2016 13:43:51 +1000 Received: from camb691.ozlabs.ibm.com (haven.au.ibm.com [9.192.254.114]) (using TLSv1.2 with cipher DHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.au.ibm.com (Postfix) with ESMTPSA id CB49FA0306; Wed, 17 Aug 2016 13:43:50 +1000 (AEST) From: Cyril Bur To: linuxppc-dev@lists.ozlabs.org, wei.guo.simon@gmail.com Subject: [PATCH v3 04/21] powerpc: Return the new MSR from msr_check_and_set() Date: Wed, 17 Aug 2016 13:43:06 +1000 X-Mailer: git-send-email 2.9.3 In-Reply-To: <20160817034323.23053-1-cyrilbur@gmail.com> References: <20160817034323.23053-1-cyrilbur@gmail.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16081703-0012-0000-0000-000001B87ABB X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16081703-0013-0000-0000-000005CA9044 Message-Id: <20160817034323.23053-5-cyrilbur@gmail.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2016-08-17_02:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_spam_definite policy=outbound score=100 spamscore=100 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000 definitions=main-1608170054 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mikey@neuling.org, anton@samba.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" mfmsr() is a fairly expensive call and callers of msr_check_and_set() may want to make decisions bits in the MSR that it did not change but may not know the value of. This patch would avoid a two calls to mfmsr(). Signed-off-by: Cyril Bur --- arch/powerpc/include/asm/reg.h | 2 +- arch/powerpc/kernel/process.c | 4 +++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index f69f40f..0a3dde9 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -1247,7 +1247,7 @@ static inline void mtmsr_isync(unsigned long val) : "memory") #endif -extern void msr_check_and_set(unsigned long bits); +extern unsigned long msr_check_and_set(unsigned long bits); extern bool strict_msr_control; extern void __msr_check_and_clear(unsigned long bits); static inline void msr_check_and_clear(unsigned long bits) diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 82308fd..c42581b 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -110,7 +110,7 @@ static int __init enable_strict_msr_control(char *str) } early_param("ppc_strict_facility_enable", enable_strict_msr_control); -void msr_check_and_set(unsigned long bits) +unsigned long msr_check_and_set(unsigned long bits) { unsigned long oldmsr = mfmsr(); unsigned long newmsr; @@ -124,6 +124,8 @@ void msr_check_and_set(unsigned long bits) if (oldmsr != newmsr) mtmsr_isync(newmsr); + + return newmsr; } void __msr_check_and_clear(unsigned long bits)