From patchwork Wed Aug 19 13:08:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 276053 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=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, 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 8FC9FC433E1 for ; Wed, 19 Aug 2020 13:10:05 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 62E3A206FA for ; Wed, 19 Aug 2020 13:10:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 62E3A206FA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kaod.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:42224 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k8Nqu-0007EA-Ly for qemu-devel@archiver.kernel.org; Wed, 19 Aug 2020 09:10:04 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52100) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k8Npp-0004zW-Oo; Wed, 19 Aug 2020 09:08:57 -0400 Received: from smtpout1.mo804.mail-out.ovh.net ([79.137.123.220]:42605) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k8Npm-0006MC-JD; Wed, 19 Aug 2020 09:08:57 -0400 Received: from mxplan5.mail.ovh.net (unknown [10.108.20.52]) by mo804.mail-out.ovh.net (Postfix) with ESMTPS id 1416658A0B90; Wed, 19 Aug 2020 15:08:53 +0200 (CEST) Received: from kaod.org (37.59.142.98) by DAG4EX1.mxp5.local (172.16.2.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Wed, 19 Aug 2020 15:08:51 +0200 Authentication-Results: garm.ovh; auth=pass (GARM-98R002bc53b74f-525f-4d1f-82f7-eb4efdbd18b4, 56ABA3BD09B5898CED80C8E013D4E39E9C6048D1) smtp.auth=clg@kaod.org From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: David Gibson Subject: [PATCH 5/8] spapr/xive: Enforce the load-after-store ordering Date: Wed, 19 Aug 2020 15:08:40 +0200 Message-ID: <20200819130843.2230799-6-clg@kaod.org> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200819130843.2230799-1-clg@kaod.org> References: <20200819130843.2230799-1-clg@kaod.org> MIME-Version: 1.0 X-Originating-IP: [37.59.142.98] X-ClientProxiedBy: DAG2EX1.mxp5.local (172.16.2.11) To DAG4EX1.mxp5.local (172.16.2.31) X-Ovh-Tracer-GUID: 9a811dae-fe7a-4c1a-8e37-e9cbf6abbc66 X-Ovh-Tracer-Id: 2622220883518982950 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduiedruddtkedggeegucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuqfggjfdpvefjgfevmfevgfenuceurghilhhouhhtmecuhedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhephffvufffkffojghfgggtgfhisehtkeertdertdejnecuhfhrohhmpeevrogurhhitgcunfgvucfiohgrthgvrhcuoegtlhhgsehkrghougdrohhrgheqnecuggftrfgrthhtvghrnhepheehfeegjeeitdfffeetjeduveejueefuefgtdefueelueetveeliefhhffgtdelnecukfhppedtrddtrddtrddtpdefjedrheelrddugedvrdelkeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhhouggvpehsmhhtphdqohhuthdphhgvlhhopehmgihplhgrnhehrdhmrghilhdrohhvhhdrnhgvthdpihhnvghtpedtrddtrddtrddtpdhmrghilhhfrhhomheptghlgheskhgrohgurdhorhhgpdhrtghpthhtoheptghlgheskhgrohgurdhorhhg Received-SPF: pass client-ip=79.137.123.220; envelope-from=clg@kaod.org; helo=smtpout1.mo804.mail-out.ovh.net X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/19 09:08:51 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org, =?utf-8?q?C=C3=A9dric_Le_Goater?= , qemu-ppc@nongnu.org, Greg Kurz , Gustavo Romero Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The XIVE_ESB_SET_PQ_10 load operation is used to disable temporarily an interrupt source. If StoreEOI is active, a source could be left enabled if the load and store operations come out of order. QEMU makes use of this offset to quiesce the sources before a migration. Enforce the load-after-store ordering always when doing so without querying the characteristics of the sources on the host. The performance penalty will be very small for QEMU. Signed-off-by: Cédric Le Goater --- include/hw/ppc/xive.h | 8 ++++++++ hw/intc/spapr_xive_kvm.c | 12 ++++++++++++ 2 files changed, 20 insertions(+) diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h index 2c42ae92d287..c061230ea802 100644 --- a/include/hw/ppc/xive.h +++ b/include/hw/ppc/xive.h @@ -279,6 +279,14 @@ static inline hwaddr xive_source_esb_mgmt(XiveSource *xsrc, int srcno) #define XIVE_ESB_SET_PQ_10 0xe00 /* Load */ #define XIVE_ESB_SET_PQ_11 0xf00 /* Load */ +/* + * Load-after-store ordering + * + * Adding this offset to the load address will enforce + * load-after-store ordering. This is required to use with StoreEOI. + */ +#define XIVE_ESB_LD_ST_MO 0x40 /* Load-after-store ordering */ + uint8_t xive_source_esb_get(XiveSource *xsrc, uint32_t srcno); uint8_t xive_source_esb_set(XiveSource *xsrc, uint32_t srcno, uint8_t pq); diff --git a/hw/intc/spapr_xive_kvm.c b/hw/intc/spapr_xive_kvm.c index 90f4509e6959..3eea4cb1c49f 100644 --- a/hw/intc/spapr_xive_kvm.c +++ b/hw/intc/spapr_xive_kvm.c @@ -317,6 +317,18 @@ static uint64_t xive_esb_rw(XiveSource *xsrc, int srcno, uint32_t offset, static uint8_t xive_esb_read(XiveSource *xsrc, int srcno, uint32_t offset) { + /* + * The XIVE_ESB_SET_PQ_10 load operation is used to disable + * temporarily an interrupt source. If StoreEOI is active, a + * source could be left enabled if the load and store operations + * come out of order. + * + * Enforce the load-after-store ordering always. + */ + if (offset == XIVE_ESB_SET_PQ_10) { + offset |= XIVE_ESB_LD_ST_MO; + } + return xive_esb_rw(xsrc, srcno, offset, 0, 0) & 0x3; }