From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by dpdk.org (Postfix) with ESMTP id A2E301B645; Tue, 9 Oct 2018 22:56:29 +0200 (CEST) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E92FC30820CE; Tue, 9 Oct 2018 20:56:28 +0000 (UTC) Received: from localhost.localdomain (unknown [10.36.112.13]) by smtp.corp.redhat.com (Postfix) with ESMTP id 81946752DE; Tue, 9 Oct 2018 20:56:25 +0000 (UTC) From: Maxime Coquelin To: dev@dpdk.org, tiwei.bie@intel.com, zhihong.wang@intel.com, jfreimann@redhat.com, nicknickolaev@gmail.com, i.maximets@samsung.com, bruce.richardson@intel.com, alejandro.lucero@netronome.com Cc: dgilbert@redhat.com, stable@dpdk.org, Maxime Coquelin Date: Tue, 9 Oct 2018 22:54:24 +0200 Message-Id: <20181009205426.21219-18-maxime.coquelin@redhat.com> In-Reply-To: <20181009205426.21219-1-maxime.coquelin@redhat.com> References: <20181009205426.21219-1-maxime.coquelin@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.47]); Tue, 09 Oct 2018 20:56:29 +0000 (UTC) Subject: [dpdk-stable] [PATCH v5 17/19] vhost: restrict postcopy live-migration enablement X-BeenThere: stable@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches for DPDK stable branches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Oct 2018 20:56:30 -0000 Postcopy live-migration feature requires the application to not populate the guest memory. As the vhost library cannot prevent the application to that (e.g. preventing the application to call mlockall()), the feature is disabled by default. The application should only enable the feature if it does not force the guest memory to be populated. In case the user passes the RTE_VHOST_USER_POSTCOPY_SUPPORT flag at registration but the feature was not compiled, registration fails. For the same reason, postcopy and dequeue zero copy features are not compatible, so don't advertize postcopy support if dequeue zero copy is requested. Signed-off-by: Maxime Coquelin --- doc/guides/prog_guide/vhost_lib.rst | 8 ++++++++ lib/librte_vhost/rte_vhost.h | 1 + lib/librte_vhost/socket.c | 30 ++++++++++++++++++++++++++--- 3 files changed, 36 insertions(+), 3 deletions(-) diff --git a/doc/guides/prog_guide/vhost_lib.rst b/doc/guides/prog_guide/vhost_lib.rst index 77af4d775..c77df338f 100644 --- a/doc/guides/prog_guide/vhost_lib.rst +++ b/doc/guides/prog_guide/vhost_lib.rst @@ -106,6 +106,14 @@ The following is an overview of some key Vhost API functions: Enabling this flag with these Qemu version results in Qemu being blocked when multiple queue pairs are declared. + - ``RTE_VHOST_USER_POSTCOPY_SUPPORT`` + + Postcopy live-migration support will be enabled when this flag is set. + It is disabled by default. + + Enabling this flag should only be done when the calling application does + not pre-fault the guest shared memory, otherwise migration would fail. + * ``rte_vhost_driver_set_features(path, features)`` This function sets the feature bits the vhost-user driver supports. The diff --git a/lib/librte_vhost/rte_vhost.h b/lib/librte_vhost/rte_vhost.h index 9292c89c5..d280ac420 100644 --- a/lib/librte_vhost/rte_vhost.h +++ b/lib/librte_vhost/rte_vhost.h @@ -28,6 +28,7 @@ extern "C" { #define RTE_VHOST_USER_NO_RECONNECT (1ULL << 1) #define RTE_VHOST_USER_DEQUEUE_ZERO_COPY (1ULL << 2) #define RTE_VHOST_USER_IOMMU_SUPPORT (1ULL << 3) +#define RTE_VHOST_USER_POSTCOPY_SUPPORT (1ULL << 4) /** Protocol features. */ #ifndef VHOST_USER_PROTOCOL_F_MQ diff --git a/lib/librte_vhost/socket.c b/lib/librte_vhost/socket.c index 7cad5593e..4b221a805 100644 --- a/lib/librte_vhost/socket.c +++ b/lib/librte_vhost/socket.c @@ -51,6 +51,8 @@ struct vhost_user_socket { uint64_t supported_features; uint64_t features; + uint64_t protocol_features; + /* * Device id to identify a specific backend device. * It's set to -1 for the default software implementation. @@ -735,7 +737,7 @@ rte_vhost_driver_get_protocol_features(const char *path, did = vsocket->vdpa_dev_id; vdpa_dev = rte_vdpa_get_device(did); if (!vdpa_dev || !vdpa_dev->ops->get_protocol_features) { - *protocol_features = VHOST_USER_PROTOCOL_FEATURES; + *protocol_features = vsocket->protocol_features; goto unlock_exit; } @@ -748,7 +750,7 @@ rte_vhost_driver_get_protocol_features(const char *path, goto unlock_exit; } - *protocol_features = VHOST_USER_PROTOCOL_FEATURES + *protocol_features = vsocket->protocol_features & vdpa_protocol_features; unlock_exit: @@ -867,11 +869,21 @@ rte_vhost_driver_register(const char *path, uint64_t flags) vsocket->use_builtin_virtio_net = true; vsocket->supported_features = VIRTIO_NET_SUPPORTED_FEATURES; vsocket->features = VIRTIO_NET_SUPPORTED_FEATURES; + vsocket->protocol_features = VHOST_USER_PROTOCOL_FEATURES; - /* Dequeue zero copy can't assure descriptors returned in order */ + /* + * Dequeue zero copy can't assure descriptors returned in order. + * Also, it requires that the guest memory is populated, which is + * not compatible with postcopy. + */ if (vsocket->dequeue_zero_copy) { vsocket->supported_features &= ~(1ULL << VIRTIO_F_IN_ORDER); vsocket->features &= ~(1ULL << VIRTIO_F_IN_ORDER); + + RTE_LOG(INFO, VHOST_CONFIG, + "Dequeue zero copy requested, disabling postcopy support\n"); + vsocket->protocol_features &= + ~(1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT); } if (!(flags & RTE_VHOST_USER_IOMMU_SUPPORT)) { @@ -879,6 +891,18 @@ rte_vhost_driver_register(const char *path, uint64_t flags) vsocket->features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM); } + if (!(flags & RTE_VHOST_USER_POSTCOPY_SUPPORT)) { + vsocket->protocol_features &= + ~(1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT); + } else { +#ifndef RTE_LIBRTE_VHOST_POSTCOPY + RTE_LOG(ERR, VHOST_CONFIG, + "Postcopy requested but not compiled\n"); + ret = -1; + goto out_mutex; +#endif + } + if ((flags & RTE_VHOST_USER_CLIENT) != 0) { vsocket->reconnect = !(flags & RTE_VHOST_USER_NO_RECONNECT); if (vsocket->reconnect && reconn_tid == 0) { -- 2.17.1