From patchwork Tue Feb 16 14:27:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Edmondson X-Patchwork-Id: 12090071 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=-11.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, 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 A7547C433DB for ; Tue, 16 Feb 2021 14:30:34 +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 1E41264DDA for ; Tue, 16 Feb 2021 14:30:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1E41264DDA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:59404 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lC1N3-0007BU-6O for qemu-devel@archiver.kernel.org; Tue, 16 Feb 2021 09:30:33 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:33276) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lC1KG-0003RC-HE; Tue, 16 Feb 2021 09:27:40 -0500 Received: from aserp2130.oracle.com ([141.146.126.79]:46504) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lC1KC-00024f-Av; Tue, 16 Feb 2021 09:27:40 -0500 Received: from pps.filterd (aserp2130.oracle.com [127.0.0.1]) by aserp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 11GEOieL063927; Tue, 16 Feb 2021 14:27:29 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : content-transfer-encoding : content-type : mime-version; s=corp-2020-01-29; bh=i/qBn8aoph4obT03NtSoWix8aQJNq35fmzLtWnqUZMs=; b=Ln/panJeYsprI07r+ZOPv2QVy+37N7fK3wBxKS4rRemFy98vEnxMebzHwbfYOteF9R7h QJy53YTN051N9/k2BaJW4Rnv4LlbKUibClw1elXBKBFK97PHLtqENbLsqS73G+suEhJq CwSKVT9KqBye/zwNgD8mEWVFD4SyaH2UU5t0wr8BHEWzcpoC4b+s3+WOtoUgUORxGqLw v+TlTb9vuaQ0S1AuD0LGnUaOsYFZHrr3GzStOjEhxRmo3O362szv+DPG91/VJ4LbvCpf ctl5jzpSHQ7SZyscM7QV4d8T1bvxXZAC+uEjdC2TgMWLhKNLSuN/gcvQL6dfrwVzBaLx ZA== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by aserp2130.oracle.com with ESMTP id 36p49b74cg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 16 Feb 2021 14:27:29 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 11GEQJg9076540; Tue, 16 Feb 2021 14:27:29 GMT Received: from nam10-mw2-obe.outbound.protection.outlook.com (mail-mw2nam10lp2103.outbound.protection.outlook.com [104.47.55.103]) by aserp3030.oracle.com with ESMTP id 36prbn7vds-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 16 Feb 2021 14:27:28 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=U7v9JPYo9PHHWXQL3SX5CK3CWLFet50EZuW7lLXt63CbOHVfQULnXFcH0yPFUE0KulLo8CTgrwHJAjNEMemVCpkVver1qPUBoIJ4nE0aYtxw6bcniZxpg9CqxL9VIbMPW57DNnVMBeUYaOGQwvddAkAfJlhTnm0UiwsMZfmbWw18BSf4NrWIf/3FE6AAR1KMZQE0w6Hhq0v138uVLXLSsE4eluvaTQ0OpUDjDqhooroR1mN+EkWmi1IRNcriMeSmkrTu2L4VX4EaYSkzIV9/SO/A/lkRMBW7x1htDqTl6nlBU+THfMmcXBdp1KfoM2IQrLOxtEfeDOgipZx6lJcsog== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=i/qBn8aoph4obT03NtSoWix8aQJNq35fmzLtWnqUZMs=; b=TZhA61EQ2U7nsgetN+mf7YviJjgkRbSmZafaCBENEUhXFosv87PS18lpgzJLW/ch14rv3bwziKTamFXsOeng5AUzZkbX+hd9wKugEda+lsHqzDSO2dWyHhrcU29gNl16jCQ/QDzKTfFcqIm1VyYEY9vfDIxUCHP/YGoRjRdWmnUUG6QpU81tY2OO1KrGixkko/Q2T//U/AxWaj5K5lGfngEtjZZ/9gRKyTQx+10YF+jiOfejqbtyrTf1tEur7BMWnj2hL7Qpcb4Gtj7nHKNLLoYc06z3Y7VVaMKYzyjbAk82zS30OnAHkebHFrgXRzzVxK1MUp9kdpwH6/rue32EfQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=i/qBn8aoph4obT03NtSoWix8aQJNq35fmzLtWnqUZMs=; b=tISAL8QeuoiBrv7/GFFkSzIsotu8guIjFAc72sGBOfngjGMD2fEEtRvMW7RMoy3YSjzCZ6hnofFBgzhA4acYZtU5mUi7IboTUZohXmVnfY9ov7i2YHcp56Pttm4EgbrHU4BF6Mao6hXYHgbKlgdGfUiDBc1po8OCQp9VrRLw1Yw= Authentication-Results: redhat.com; dkim=none (message not signed) header.d=none;redhat.com; dmarc=none action=none header.from=oracle.com; Received: from DM6PR10MB3148.namprd10.prod.outlook.com (2603:10b6:5:1a4::21) by DS7PR10MB5182.namprd10.prod.outlook.com (2603:10b6:5:38f::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3846.27; Tue, 16 Feb 2021 14:27:27 +0000 Received: from DM6PR10MB3148.namprd10.prod.outlook.com ([fe80::f871:5965:2081:3934]) by DM6PR10MB3148.namprd10.prod.outlook.com ([fe80::f871:5965:2081:3934%5]) with mapi id 15.20.3846.027; Tue, 16 Feb 2021 14:27:26 +0000 From: David Edmondson To: qemu-devel@nongnu.org Subject: [RFC PATCH 0/3] hw/pflash_cfi01: Reduce memory consumption when flash image is smaller than region Date: Tue, 16 Feb 2021 14:27:17 +0000 Message-Id: <20210216142721.1985543-1-david.edmondson@oracle.com> X-Mailer: git-send-email 2.30.0 X-Originating-IP: [2001:8b0:bb71:7140:64::1] X-ClientProxiedBy: LO4P123CA0096.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:191::11) To DM6PR10MB3148.namprd10.prod.outlook.com (2603:10b6:5:1a4::21) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from disaster-area.hh.sledj.net (2001:8b0:bb71:7140:64::1) by LO4P123CA0096.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:191::11) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3846.35 via Frontend Transport; Tue, 16 Feb 2021 14:27:25 +0000 Received: from localhost (disaster-area.hh.sledj.net [local]) by disaster-area.hh.sledj.net (OpenSMTPD) with ESMTPA id 06571195; Tue, 16 Feb 2021 14:27:21 +0000 (UTC) X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: cc53e8dd-7837-443b-b292-08d8d286fb92 X-MS-TrafficTypeDiagnostic: DS7PR10MB5182: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:10000; X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:DM6PR10MB3148.namprd10.prod.outlook.com; PTR:; CAT:NONE; SFS:(396003)(346002)(39860400002)(376002)(366004)(136003)(2906002)(86362001)(478600001)(44832011)(1076003)(6966003)(316002)(54906003)(52116002)(6666004)(66946007)(36756003)(66556008)(8676002)(6916009)(66476007)(8936002)(2616005)(5660300002)(966005)(107886003)(83380400001)(186003)(4326008); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData: 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 X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: cc53e8dd-7837-443b-b292-08d8d286fb92 X-MS-Exchange-CrossTenant-AuthSource: DM6PR10MB3148.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Feb 2021 14:27:26.8266 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: wn6PwAD9NJ1T1tzYtjREIjZud0XN9hcwvA88fiRArC3LCR2m1YfyrLOUC4AhHBIGP98JavR3Y7a0kGt6r+6OMqEHzZibSqdhBh9fOWjpBMU= X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR10MB5182 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=9896 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 spamscore=0 mlxscore=0 phishscore=0 adultscore=0 bulkscore=0 mlxlogscore=999 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2102160133 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=9896 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 priorityscore=1501 lowpriorityscore=0 bulkscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 malwarescore=0 phishscore=0 clxscore=1011 mlxscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2102160133 Received-SPF: pass client-ip=141.146.126.79; envelope-from=david.edmondson@oracle.com; helo=aserp2130.oracle.com X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, MSGID_FROM_MTA_HEADER=0.001, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, UNPARSEABLE_RELAY=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: Kevin Wolf , David Edmondson , =?utf-8?q?Philippe_Mathieu-Da?= =?utf-8?q?ud=C3=A9?= , qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" As described in https://lore.kernel.org/r/20201116104216.439650-1-david.edmondson@oracle.com, I'd like to reduce the amount of memory consumed by QEMU mapping UEFI images on aarch64. To recap: > Currently ARM UEFI images are typically built as 2MB/768kB flash > images for code and variables respectively. These images are both > then padded out to 64MB before being loaded by QEMU. > > Because the images are 64MB each, QEMU allocates 128MB of memory to > read them, and then proceeds to read all 128MB from disk (dirtying > the memory). Of this 128MB less than 3MB is useful - the rest is > zero padding. > > On a machine with 100 VMs this wastes over 12GB of memory. There were objections to my previous patch because it changed the size of the regions reported to the guest via the memory map (the reported size depended on the size of the image). This is a smaller patch which only helps with read-only flash images, as it does so by changing the memory region that covers the entire region to be IO rather than RAM, and loads the flash image into a smaller sub-region that is the more traditional mixed IO/ROMD type. All read/write operations to areas outside of the underlying block device are handled directly (reads return 0, writes fail (which is okay, because this path only supports read-only devices)). This reduces the memory consumption for the read-only AAVMF code image from 64MB to around 2MB (presuming that the UEFI image is adjusted accordingly). It does nothing to improve the memory consumption caused by the read-write AAVMF vars image. There was a suggestion in a previous thread that perhaps the pflash driver could be re-worked to use the block IO interfaces to access the underlying device "on demand" rather than reading in the entire image at startup (at least, that's how I understood the comment). I looked at implementing this and struggled to get it to work for all of the required use cases. Specifically, there are several code paths that expect to retrieve a pointer to the flat memory image of the pflash device and manipulate it directly (examples include the Malta board and encrypted memory support on x86), or write the entire image to storage (after migration). My implementation was based around mapping the flash region only for IO, which meant that every read or write had to be handled directly by the pflash driver (there was no ROMD style operation), which also made booting an aarch64 VM noticeably slower - getting through the firmware went from under 1 second to around 10 seconds. Improving the writeable device support requires some more general infrastructure, I think, but I'm not familiar with everything that QEMU currently provides, and would be very happy to learn otherwise. David Edmondson (3): hw/pflash_cfi*: Replace DPRINTF with trace events hw/pflash_cfi01: Correct the type of PFlashCFI01.ro hw/pflash_cfi01: Allow read-only devices to have a smaller backing device hw/block/pflash_cfi01.c | 197 +++++++++++++++++++++++++--------------- hw/block/pflash_cfi02.c | 75 ++++++--------- hw/block/trace-events | 42 +++++++-- 3 files changed, 186 insertions(+), 128 deletions(-)