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{ "id": 64037, "url": "http://patches.dpdk.org/api/covers/64037/?format=api", "web_url": "http://patches.dpdk.org/project/dpdk/cover/1576811391-19131-1-git-send-email-gavin.hu@arm.com/", "project": { "id": 1, "url": "http://patches.dpdk.org/api/projects/1/?format=api", "name": "DPDK", "link_name": "dpdk", "list_id": "dev.dpdk.org", "list_email": "dev@dpdk.org", "web_url": "http://core.dpdk.org", "scm_url": "git://dpdk.org/dpdk", "webscm_url": "http://git.dpdk.org/dpdk", "list_archive_url": "https://inbox.dpdk.org/dev", "list_archive_url_format": "https://inbox.dpdk.org/dev/{}", "commit_url_format": "" }, "msgid": "<1576811391-19131-1-git-send-email-gavin.hu@arm.com>", "list_archive_url": "https://inbox.dpdk.org/dev/1576811391-19131-1-git-send-email-gavin.hu@arm.com", "date": "2019-12-20T03:09:48", "name": "[v2,0/3] relax io barrier for aarch64 and use smp barriers for virtual pci memory", "submitter": { "id": 1018, "url": "http://patches.dpdk.org/api/people/1018/?format=api", "name": "Gavin Hu", "email": "gavin.hu@arm.com" }, "mbox": "http://patches.dpdk.org/project/dpdk/cover/1576811391-19131-1-git-send-email-gavin.hu@arm.com/mbox/", "series": [ { "id": 7901, "url": "http://patches.dpdk.org/api/series/7901/?format=api", "web_url": "http://patches.dpdk.org/project/dpdk/list/?series=7901", "date": "2019-12-20T03:09:48", "name": "relax io barrier for aarch64 and use smp barriers for virtual pci memory", "version": 2, "mbox": "http://patches.dpdk.org/series/7901/mbox/" } ], "comments": "http://patches.dpdk.org/api/covers/64037/comments/", "headers": { "Return-Path": "<dev-bounces@dpdk.org>", "X-Original-To": "patchwork@inbox.dpdk.org", "Delivered-To": "patchwork@inbox.dpdk.org", "Received": [ "from dpdk.org (dpdk.org [92.243.14.124])\n\tby inbox.dpdk.org (Postfix) with ESMTP id 7EF14A04F3;\n\tFri, 20 Dec 2019 04:10:31 +0100 (CET)", "from [92.243.14.124] (localhost [127.0.0.1])\n\tby dpdk.org (Postfix) with ESMTP id 8F7F41BE3D;\n\tFri, 20 Dec 2019 04:10:30 +0100 (CET)", "from foss.arm.com (foss.arm.com [217.140.110.172])\n by dpdk.org (Postfix) with ESMTP id 6E0535B3C\n for <dev@dpdk.org>; Fri, 20 Dec 2019 04:10:28 +0100 (CET)", "from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14])\n by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B5DC830E;\n Thu, 19 Dec 2019 19:10:27 -0800 (PST)", "from net-arm-thunderx2-01.test.ast.arm.com\n (net-arm-thunderx2-01.shanghai.arm.com [10.169.40.68])\n by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E8C493F719;\n Thu, 19 Dec 2019 19:10:22 -0800 (PST)" ], "From": "Gavin Hu <gavin.hu@arm.com>", "To": "dev@dpdk.org", "Cc": "nd@arm.com, david.marchand@redhat.com, maxime.coquelin@redhat.com,\n tiwei.bie@intel.com, thomas@monjalon.net, rasland@mellanox.com,\n matan@mellanox.com, shahafs@mellanox.com, viacheslavo@mellanox.com,\n arybchenko@solarflare.com, stephen@networkplumber.org,\n hemant.agrawal@nxp.com, jerinj@marvell.com, pbhagavatula@marvell.com,\n Honnappa.Nagarahalli@arm.com, ruifeng.wang@arm.com, phil.yang@arm.com,\n joyce.kong@arm.com, steve.capper@arm.com", "Date": "Fri, 20 Dec 2019 11:09:48 +0800", "Message-Id": "<1576811391-19131-1-git-send-email-gavin.hu@arm.com>", "X-Mailer": "git-send-email 2.7.4", "In-Reply-To": "<1571758074-16445-1-git-send-email-gavin.hu@arm.com>", "References": "<1571758074-16445-1-git-send-email-gavin.hu@arm.com>", "MIME-Version": "1.0", "Content-Type": "text/plain; charset=UTF-8", "Content-Transfer-Encoding": "8bit", "Subject": "[dpdk-dev] [PATCH v2 0/3] relax io barrier for aarch64 and use smp\n\tbarriers for virtual pci memory", "X-BeenThere": "dev@dpdk.org", "X-Mailman-Version": "2.1.15", "Precedence": "list", "List-Id": "DPDK patches and discussions <dev.dpdk.org>", "List-Unsubscribe": "<https://mails.dpdk.org/options/dev>,\n <mailto:dev-request@dpdk.org?subject=unsubscribe>", "List-Archive": "<http://mails.dpdk.org/archives/dev/>", "List-Post": "<mailto:dev@dpdk.org>", "List-Help": "<mailto:dev-request@dpdk.org?subject=help>", "List-Subscribe": "<https://mails.dpdk.org/listinfo/dev>,\n <mailto:dev-request@dpdk.org?subject=subscribe>", "Errors-To": "dev-bounces@dpdk.org", "Sender": "\"dev\" <dev-bounces@dpdk.org>" }, "content": "Armv8's peripheral coherence order is a total order on all reads and\nwrites to that peripheral, that makes a compiler barrier is enough for\nabstracted rte io barrier.\n\nFor virtual PCI devices, the virtual device memory is actually normal\nmemory and the Hypervisor view of things takes precedence and they are\nwithin a smp configuration and smp barriers should be used, the\nrelaxed io barrier for aarch64 becomes insufficient.\n\nNote for the ordering of other MMIO device memories, other than PCI,\nstronger barriers might be required, which depends on the memory attributes\nassigned to the memory regions. So far I did not find occurrences of such\nio barriers used in non-PCI device memories within DPDK.\n\nV2:\n- remove virtio_pci_read/write64 APIs definitions, they are not needed and generate compiling errors like \" error: unused function 'virtio_pci_write64' [-Werror,-Wunused-function]\"\n- update the reference link to kernel source code \n\nGavin Hu (3):\n eal/arm64: relax the io barrier for aarch64\n net/virtio: virtual PCI requires smp barriers\n crypto/virtio: virtual PCI requires smp barriers\n\n drivers/crypto/virtio/virtio_pci.c | 108 +++++++++++++++------\n drivers/net/virtio/virtio_pci.c | 108 +++++++++++++++------\n .../common/include/arch/arm/rte_atomic_64.h | 6 +-\n 3 files changed, 159 insertions(+), 63 deletions(-)" }