From patchwork Thu Apr 6 10:22:48 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Nikunj A. Dadhania" X-Patchwork-Id: 9666793 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B582A60364 for ; Thu, 6 Apr 2017 10:27:32 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 980502793A for ; Thu, 6 Apr 2017 10:27:32 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8C93428178; Thu, 6 Apr 2017 10:27:32 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 39C982793A for ; Thu, 6 Apr 2017 10:27:32 +0000 (UTC) Received: from localhost ([::1]:44700 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cw4dX-0004j3-C8 for patchwork-qemu-devel@patchwork.kernel.org; Thu, 06 Apr 2017 06:27:31 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58112) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cw4aM-0002vu-Rf for qemu-devel@nongnu.org; Thu, 06 Apr 2017 06:24:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cw4aH-0004GN-Su for qemu-devel@nongnu.org; Thu, 06 Apr 2017 06:24:14 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:42676) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cw4aH-0004G1-I0 for qemu-devel@nongnu.org; Thu, 06 Apr 2017 06:24:09 -0400 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v36ANqsb138749 for ; Thu, 6 Apr 2017 06:24:08 -0400 Received: from e23smtp04.au.ibm.com (e23smtp04.au.ibm.com [202.81.31.146]) by mx0a-001b2d01.pphosted.com with ESMTP id 29n1byvg61-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 06 Apr 2017 06:24:08 -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; Thu, 6 Apr 2017 20:24:03 +1000 Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay08.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v36ANtP653018864; Thu, 6 Apr 2017 20:24:03 +1000 Received: from d23av04.au.ibm.com (localhost [127.0.0.1]) by d23av04.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id v36ANTgl016338; Thu, 6 Apr 2017 20:23:30 +1000 Received: from abhimanyu.in.ibm.com ([9.109.222.83]) by d23av04.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id v36ANMgg016025; Thu, 6 Apr 2017 20:23:27 +1000 From: Nikunj A Dadhania To: qemu-ppc@nongnu.org, david@gibson.dropbear.id.au, rth@twiddle.net Date: Thu, 6 Apr 2017 15:52:48 +0530 X-Mailer: git-send-email 2.9.3 In-Reply-To: <20170406102249.20383-1-nikunj@linux.vnet.ibm.com> References: <20170406102249.20383-1-nikunj@linux.vnet.ibm.com> X-TM-AS-MML: disable x-cbid: 17040610-0012-0000-0000-00000224CAFF X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17040610-0013-0000-0000-00000739FC99 Message-Id: <20170406102249.20383-3-nikunj@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-04-06_08:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1702020001 definitions=main-1704060086 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.156.1 Subject: [Qemu-devel] [PATCH RFC v1 2/3] cputlb: handle first atomic write to the page X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: programmingkidx@gmail.com, alex.bennee@linaro.org, qemu-devel@nongnu.org, nikunj@linux.vnet.ibm.com, bharata@linux.vnet.ibm.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP In case where the conditional write is the first write to the page, TLB_NOTDIRTY will be set and stop_the_world is triggered. Handle this as a special case and set the dirty bit. After that fall through to the actual atomic instruction below. Signed-off-by: Nikunj A Dadhania Reviewed-by: Richard Henderson --- cputlb.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/cputlb.c b/cputlb.c index f5d056c..743776a 100644 --- a/cputlb.c +++ b/cputlb.c @@ -930,7 +930,13 @@ static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr, tlb_addr = tlbe->addr_write; } - /* Notice an IO access, or a notdirty page. */ + /* Check notdirty */ + if (unlikely(tlb_addr & TLB_NOTDIRTY)) { + tlb_set_dirty(ENV_GET_CPU(env), addr); + tlb_addr = tlb_addr & ~TLB_NOTDIRTY; + } + + /* Notice an IO access */ if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) { /* There's really nothing that can be done to support this apart from stop-the-world. */