From patchwork Sun Jan 25 11:03:29 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen Gang X-Patchwork-Id: 432492 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id DB8AF1401D0 for ; Sun, 25 Jan 2015 21:56:31 +1100 (AEDT) Received: from localhost ([::1]:37356 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YFKrl-00072J-Au for incoming@patchwork.ozlabs.org; Sun, 25 Jan 2015 05:56:29 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50541) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YFKrS-0006b5-Oe for qemu-devel@nongnu.org; Sun, 25 Jan 2015 05:56:11 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YFKrP-0007UH-If for qemu-devel@nongnu.org; Sun, 25 Jan 2015 05:56:10 -0500 Received: from out11.biz.mail.alibaba.com ([205.204.114.131]:40086) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YFKrP-0007Tc-7e; Sun, 25 Jan 2015 05:56:07 -0500 X-Alimail-AntiSpam: AC=CONTINUE; BC=0.1252449|-1; FP=0|0|0|0|0|-1|-1|-1; HT=r41g03020; MF=gang.chen@sunrus.com.cn; PH=DS; RN=5; RT=5; SR=0; Received: from ShengShiZhuChengdeMacBook-Pro.local(mailfrom:gang.chen@sunrus.com.cn ip:223.72.65.110) by smtp.aliyun-inc.com(10.194.100.109); Sun, 25 Jan 2015 18:55:49 +0800 Message-ID: <54C4CD81.10503@sunrus.com.cn> Date: Sun, 25 Jan 2015 19:03:29 +0800 From: Chen Gang S User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: riku.voipio@iki.fi, david.gilbert@linaro.org, david.gilbert@linaro.org, Peter Maydell X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 205.204.114.131 Cc: QEMU Trivial , qemu-devel Subject: [Qemu-devel] [PATCH v2] linux-user/main.c: Remove redundant end_exclusive() in arm_kernel_cmpxchg64_helper() X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org start/end_exclusive() need be pairs, except the start_exclusive() in stop_all_tasks() which is only used by force_sig(), which will be abort. So at present, start_exclusive() in stop_all_task() need not be paired. queue_signal() may call force_sig(), or return after kill pid (or queue signal). If could return from queue_signal(), stop_all_task() would not be called in time, the next end_exclusive() would be issue. So in arm_kernel_cmpxchg64_helper() for ARM, need remove end_exclusive() after queue_signal(). The related commit: "97cc756 linux-user: Implement new ARM 64 bit cmpxchg kernel helper". Signed-off-by: Chen Gang Reviewed-by: Peter Maydell --- linux-user/main.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/linux-user/main.c b/linux-user/main.c index 8c70be4..2d52c1f 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -523,8 +523,6 @@ segv: info.si_code = TARGET_SEGV_MAPERR; info._sifields._sigfault._addr = env->exception.vaddress; queue_signal(env, info.si_signo, &info); - - end_exclusive(); } /* Handle a jump to the kernel code page. */