From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 473FAC433F5 for ; Fri, 28 Jan 2022 06:14:22 +0000 (UTC) Received: from localhost ([::1]:56504 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nDKWb-0005e4-5R for qemu-devel@archiver.kernel.org; Fri, 28 Jan 2022 01:14:21 -0500 Received: from eggs.gnu.org ([209.51.188.92]:55560) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nDKKy-0000T6-4P for qemu-devel@nongnu.org; Fri, 28 Jan 2022 01:02:22 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:30549) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nDKKv-0003VT-Ds for qemu-devel@nongnu.org; Fri, 28 Jan 2022 01:02:19 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643349736; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Yakut0idUG4wT0tKpo+MdlrVnIetTsQ5NzmeTrEWMPM=; b=eUo5N9WRb5WZbD5iaxJrfPZKwkwYtEd2DdJm7X0Dhibi5pJj/2sutmDwZtzgWznLr1G+bN /wtoAlIljaxEtw79niU2ZO2wragXYfzUichsfMe9+dg3YMkzyoXKhXDYu9WNFmp6pDPpYC mJrCdQwZnfZPXjzi1+QnsHMMHDaf3no= Received: from mail-pf1-f200.google.com (mail-pf1-f200.google.com [209.85.210.200]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-654-TT6THJRNPRut8NdPDAyE9g-1; Fri, 28 Jan 2022 01:02:12 -0500 X-MC-Unique: TT6THJRNPRut8NdPDAyE9g-1 Received: by mail-pf1-f200.google.com with SMTP id z29-20020a62d11d000000b004c8f0d5dec9so2973030pfg.4 for ; Thu, 27 Jan 2022 22:02:12 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=Yakut0idUG4wT0tKpo+MdlrVnIetTsQ5NzmeTrEWMPM=; b=ocKnL37lthHB8D8TnJgyXDJh01kGB1hqNqVQ1ui/H9cY1Sz82vEtRpCu4Yc9CNl8E1 Acfst8YVP4ZHUyFNQxPrkNak62lS3JoeAhA3nzNijLsU3fdmjED840C81LvOPAjeyeZm q+C4cYgD5PpXwwxNcBh4yvPNUL5mA4kzmLx9eqBsqwNzfNfGtjlTmd6reIoy6sVO011k wb2r8Dsa5ZJMmIR2D7vPRZ8ZjT2HjJkijLhD3zXh43HbxfeTRen/5M9/qpRl5y4ydWpA 9BMYbF2ixFrMYZUvozaTXHXZHarvQkFvZ67kooHzVsn9TgDf5U8UsFcTRuqyqbtyH64s QmfQ== X-Gm-Message-State: AOAM530PfsL3mevuEnHOmgpLEQIkalpNduqEQHWPh5ySgQKnMKrLcwpl ixMBb/gILlycQ7fBNJcF21EksXLUJzOfHbAoddTuqZyHWE45V17fpVK5Egz/l80GJPbRbeaGS5o 6eViEpr5w7Rn1j9Q= X-Received: by 2002:a63:5908:: with SMTP id n8mr5383323pgb.390.1643349731509; Thu, 27 Jan 2022 22:02:11 -0800 (PST) X-Google-Smtp-Source: ABdhPJxJi4T/wXHVelQzuAQNSTnqjrUGqB/hfT1VFBwY5JbjbZeeiTdRhTRvDCIudcql9j/47h1Q+Q== X-Received: by 2002:a63:5908:: with SMTP id n8mr5383295pgb.390.1643349731067; Thu, 27 Jan 2022 22:02:11 -0800 (PST) Received: from [10.72.13.185] ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id g19sm3626369pfv.164.2022.01.27.22.02.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 27 Jan 2022 22:02:10 -0800 (PST) Message-ID: <7d86c715-6d71-8a27-91f5-8d47b71e3201@redhat.com> Date: Fri, 28 Jan 2022 14:02:02 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH 00/31] vDPA shadow virtqueue To: =?UTF-8?Q?Eugenio_P=c3=a9rez?= , qemu-devel@nongnu.org References: <20220121202733.404989-1-eperezma@redhat.com> From: Jason Wang In-Reply-To: <20220121202733.404989-1-eperezma@redhat.com> Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jasowang@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=jasowang@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.167, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , Parav Pandit , Cindy Lu , "Michael S. Tsirkin" , Juan Quintela , Richard Henderson , Markus Armbruster , Gautam Dawar , virtualization@lists.linux-foundation.org, Eduardo Habkost , Harpreet Singh Anand , Xiao W Wang , Peter Xu , Stefan Hajnoczi , Eli Cohen , Paolo Bonzini , Zhu Lingshan , Eric Blake , Stefano Garzarella Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" 在 2022/1/22 上午4:27, Eugenio Pérez 写道: > This series enables shadow virtqueue (SVQ) for vhost-vdpa devices. This > is intended as a new method of tracking the memory the devices touch > during a migration process: Instead of relay on vhost device's dirty > logging capability, SVQ intercepts the VQ dataplane forwarding the > descriptors between VM and device. This way qemu is the effective > writer of guests memory, like in qemu's emulated virtio device > operation. > > When SVQ is enabled qemu offers a new virtual address space to the > device to read and write into, and it maps new vrings and the guest > memory in it. SVQ also intercepts kicks and calls between the device > and the guest. Used buffers relay would cause dirty memory being > tracked, but at this RFC SVQ is not enabled on migration automatically. > > Thanks of being a buffers relay system, SVQ can be used also to > communicate devices and drivers with different capabilities, like > devices that only support packed vring and not split and old guests with > no driver packed support. > > It is based on the ideas of DPDK SW assisted LM, in the series of > DPDK's https://patchwork.dpdk.org/cover/48370/ . However, these does > not map the shadow vq in guest's VA, but in qemu's. > > This version of SVQ is limited in the amount of features it can use with > guest and device, because this series is already very big otherwise. > Features like indirect or event_idx will be addressed in future series. > > SVQ needs to be enabled with cmdline parameter x-svq, like: > > -netdev type=vhost-vdpa,vhostdev=/dev/vhost-vdpa-0,id=vhost-vdpa0,x-svq=true > > In this version it cannot be enabled or disabled in runtime. Further > series will remove this limitation and will enable it only for migration > time. > > Some patches are intentionally very small to ease review, but they can > be squashed if preferred. > > Patches 1-10 prepares the SVQ and QEMU to support both guest to device > and device to guest notifications forwarding, with the extra qemu hop. > That part can be tested in isolation if cmdline change is reproduced. > > Patches from 11 to 18 implement the actual buffer forwarding, but with > no IOMMU support. It requires a vdpa device capable of addressing all > qemu vaddr. > > Patches 19 to 23 adds the iommu support, so the device with address > range limitations can access SVQ through this new virtual address space > created. > > The rest of the series add the last pieces needed for migration. > > Comments are welcome. I wonder the performance impact. So performance numbers are more than welcomed. Thanks > > TODO: > * Event, indirect, packed, and other features of virtio. > * To separate buffers forwarding in its own AIO context, so we can > throw more threads to that task and we don't need to stop the main > event loop. > * Support virtio-net control vq. > * Proper documentation. > > Changes from v5 RFC: > * Remove dynamic enablement of SVQ, making less dependent of the device. > * Enable live migration if SVQ is enabled. > * Fix SVQ when driver reset. > * Comments addressed, specially in the iova area. > * Rebase on latest master, adding multiqueue support (but no networking > control vq processing). > v5 link: > https://lists.gnu.org/archive/html/qemu-devel/2021-10/msg07250.html > > Changes from v4 RFC: > * Support of allocating / freeing iova ranges in IOVA tree. Extending > already present iova-tree for that. > * Proper validation of guest features. Now SVQ can negotiate a > different set of features with the device when enabled. > * Support of host notifiers memory regions > * Handling of SVQ full queue in case guest's descriptors span to > different memory regions (qemu's VA chunks). > * Flush pending used buffers at end of SVQ operation. > * QMP command now looks by NetClientState name. Other devices will need > to implement it's way to enable vdpa. > * Rename QMP command to set, so it looks more like a way of working > * Better use of qemu error system > * Make a few assertions proper error-handling paths. > * Add more documentation > * Less coupling of virtio / vhost, that could cause friction on changes > * Addressed many other small comments and small fixes. > > Changes from v3 RFC: > * Move everything to vhost-vdpa backend. A big change, this allowed > some cleanup but more code has been added in other places. > * More use of glib utilities, especially to manage memory. > v3 link: > https://lists.nongnu.org/archive/html/qemu-devel/2021-05/msg06032.html > > Changes from v2 RFC: > * Adding vhost-vdpa devices support > * Fixed some memory leaks pointed by different comments > v2 link: > https://lists.nongnu.org/archive/html/qemu-devel/2021-03/msg05600.html > > Changes from v1 RFC: > * Use QMP instead of migration to start SVQ mode. > * Only accepting IOMMU devices, closer behavior with target devices > (vDPA) > * Fix invalid masking/unmasking of vhost call fd. > * Use of proper methods for synchronization. > * No need to modify VirtIO device code, all of the changes are > contained in vhost code. > * Delete superfluous code. > * An intermediate RFC was sent with only the notifications forwarding > changes. It can be seen in > https://patchew.org/QEMU/20210129205415.876290-1-eperezma@redhat.com/ > v1 link: > https://lists.gnu.org/archive/html/qemu-devel/2020-11/msg05372.html > > Eugenio Pérez (20): > virtio: Add VIRTIO_F_QUEUE_STATE > virtio-net: Honor VIRTIO_CONFIG_S_DEVICE_STOPPED > virtio: Add virtio_queue_is_host_notifier_enabled > vhost: Make vhost_virtqueue_{start,stop} public > vhost: Add x-vhost-enable-shadow-vq qmp > vhost: Add VhostShadowVirtqueue > vdpa: Register vdpa devices in a list > vhost: Route guest->host notification through shadow virtqueue > Add vhost_svq_get_svq_call_notifier > Add vhost_svq_set_guest_call_notifier > vdpa: Save call_fd in vhost-vdpa > vhost-vdpa: Take into account SVQ in vhost_vdpa_set_vring_call > vhost: Route host->guest notification through shadow virtqueue > virtio: Add vhost_shadow_vq_get_vring_addr > vdpa: Save host and guest features > vhost: Add vhost_svq_valid_device_features to shadow vq > vhost: Shadow virtqueue buffers forwarding > vhost: Add VhostIOVATree > vhost: Use a tree to store memory mappings > vdpa: Add custom IOTLB translations to SVQ > > Eugenio Pérez (31): > vdpa: Reorder virtio/vhost-vdpa.c functions > vhost: Add VhostShadowVirtqueue > vdpa: Add vhost_svq_get_dev_kick_notifier > vdpa: Add vhost_svq_set_svq_kick_fd > vhost: Add Shadow VirtQueue kick forwarding capabilities > vhost: Route guest->host notification through shadow virtqueue > vhost: dd vhost_svq_get_svq_call_notifier > vhost: Add vhost_svq_set_guest_call_notifier > vhost-vdpa: Take into account SVQ in vhost_vdpa_set_vring_call > vhost: Route host->guest notification through shadow virtqueue > vhost: Add vhost_svq_valid_device_features to shadow vq > vhost: Add vhost_svq_valid_guest_features to shadow vq > vhost: Add vhost_svq_ack_guest_features to shadow vq > virtio: Add vhost_shadow_vq_get_vring_addr > vdpa: Add vhost_svq_get_num > vhost: pass queue index to vhost_vq_get_addr > vdpa: adapt vhost_ops callbacks to svq > vhost: Shadow virtqueue buffers forwarding > utils: Add internal DMAMap to iova-tree > util: Store DMA entries in a list > util: Add iova_tree_alloc > vhost: Add VhostIOVATree > vdpa: Add custom IOTLB translations to SVQ > vhost: Add vhost_svq_get_last_used_idx > vdpa: Adapt vhost_vdpa_get_vring_base to SVQ > vdpa: Clear VHOST_VRING_F_LOG at vhost_vdpa_set_vring_addr in SVQ > vdpa: Never set log_base addr if SVQ is enabled > vdpa: Expose VHOST_F_LOG_ALL on SVQ > vdpa: Make ncs autofree > vdpa: Move vhost_vdpa_get_iova_range to net/vhost-vdpa.c > vdpa: Add x-svq to NetdevVhostVDPAOptions > > qapi/net.json | 5 +- > hw/virtio/vhost-iova-tree.h | 27 + > hw/virtio/vhost-shadow-virtqueue.h | 46 ++ > include/hw/virtio/vhost-vdpa.h | 7 + > include/qemu/iova-tree.h | 17 + > hw/virtio/vhost-iova-tree.c | 157 ++++++ > hw/virtio/vhost-shadow-virtqueue.c | 761 +++++++++++++++++++++++++++++ > hw/virtio/vhost-vdpa.c | 740 ++++++++++++++++++++++++---- > hw/virtio/vhost.c | 6 +- > net/vhost-vdpa.c | 58 ++- > util/iova-tree.c | 161 +++++- > hw/virtio/meson.build | 2 +- > 12 files changed, 1852 insertions(+), 135 deletions(-) > create mode 100644 hw/virtio/vhost-iova-tree.h > create mode 100644 hw/virtio/vhost-shadow-virtqueue.h > create mode 100644 hw/virtio/vhost-iova-tree.c > create mode 100644 hw/virtio/vhost-shadow-virtqueue.c >