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 BFF69C433EF for ; Thu, 19 May 2022 19:29:38 +0000 (UTC) Received: from localhost ([::1]:55900 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nrlq5-00064V-Rm for qemu-devel@archiver.kernel.org; Thu, 19 May 2022 15:29:37 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48262) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nrlb5-0005fc-7Z for qemu-devel@nongnu.org; Thu, 19 May 2022 15:14:08 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:53809) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nrlb2-0006Rp-Ii for qemu-devel@nongnu.org; Thu, 19 May 2022 15:14:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652987644; 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=CWiB2UPpPFNLsK1gITyT4zta7OXMHp9dwTDbjarxjKA=; b=MxSu1Gdcc7cTUtob4iGVqz/ZMNhwbkFUud4q+eIM+MeemvwUh1FVHAac1A/wEQj5U2GQh8 yCd3QCuS5rt5DMBYhl5qoE5ZpX12jQB3HJZsP7OyFFOeEnavcHKTkK5ADqOSgKsh9X31Wx Ga0fgpWKd8YvQZXGv4+CQ6pL2mzhoUc= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-550-xuHyKZcAP3K8SBC49GAQ7g-1; Thu, 19 May 2022 15:14:01 -0400 X-MC-Unique: xuHyKZcAP3K8SBC49GAQ7g-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 650D4800B21; Thu, 19 May 2022 19:13:54 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.193.126]) by smtp.corp.redhat.com (Postfix) with ESMTP id CF2C02024CAE; Thu, 19 May 2022 19:13:51 +0000 (UTC) From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= To: qemu-devel@nongnu.org Cc: Gautam Dawar , "Michael S. Tsirkin" , Markus Armbruster , "Gonglei (Arei)" , Harpreet Singh Anand , Cornelia Huck , Zhu Lingshan , Laurent Vivier , Eli Cohen , Paolo Bonzini , Liuxiangdong , Eric Blake , Cindy Lu , Jason Wang , Parav Pandit Subject: [RFC PATCH v8 15/21] vhost: add vhost_svq_poll Date: Thu, 19 May 2022 21:13:00 +0200 Message-Id: <20220519191306.821774-16-eperezma@redhat.com> In-Reply-To: <20220519191306.821774-1-eperezma@redhat.com> References: <20220519191306.821774-1-eperezma@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=eperezma@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" It allows the Shadow Control VirtQueue to wait the device to use the commands that restore the net device state after a live migration. Signed-off-by: Eugenio Pérez --- hw/virtio/vhost-shadow-virtqueue.h | 1 + hw/virtio/vhost-shadow-virtqueue.c | 57 +++++++++++++++++++++++++++--- 2 files changed, 54 insertions(+), 4 deletions(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h index 3c55fe2641..20ca59e9a7 100644 --- a/hw/virtio/vhost-shadow-virtqueue.h +++ b/hw/virtio/vhost-shadow-virtqueue.h @@ -124,6 +124,7 @@ bool vhost_svq_valid_features(uint64_t features, Error **errp); int vhost_svq_inject(VhostShadowVirtqueue *svq, const struct iovec *iov, size_t out_num, size_t in_num); +ssize_t vhost_svq_poll(VhostShadowVirtqueue *svq); void vhost_svq_set_svq_kick_fd(VhostShadowVirtqueue *svq, int svq_kick_fd); void vhost_svq_set_svq_call_fd(VhostShadowVirtqueue *svq, int call_fd); void vhost_svq_get_vring_addr(const VhostShadowVirtqueue *svq, diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index c535c99905..831ffb71e5 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -10,6 +10,8 @@ #include "qemu/osdep.h" #include "hw/virtio/vhost-shadow-virtqueue.h" +#include + #include "qemu/error-report.h" #include "qapi/error.h" #include "qemu/main-loop.h" @@ -583,10 +585,11 @@ static bool vhost_svq_unmap_elem(VhostShadowVirtqueue *svq, SVQElement *svq_elem return true; } -static void vhost_svq_flush(VhostShadowVirtqueue *svq, - bool check_for_avail_queue) +static size_t vhost_svq_flush(VhostShadowVirtqueue *svq, + bool check_for_avail_queue) { VirtQueue *vq = svq->vq; + size_t ret = 0; /* Forward as many used buffers as possible. */ do { @@ -604,7 +607,7 @@ static void vhost_svq_flush(VhostShadowVirtqueue *svq, if (svq->copy_descs) { bool ok = vhost_svq_unmap_elem(svq, svq_elem, len, true); if (unlikely(!ok)) { - return; + return ret; } } @@ -621,10 +624,12 @@ static void vhost_svq_flush(VhostShadowVirtqueue *svq, i, svq->vring.num); virtqueue_fill(vq, elem, len, i); virtqueue_flush(vq, i); - return; + return ret + 1; } virtqueue_fill(vq, elem, len, i++); } + + ret++; } if (i > 0) { @@ -640,6 +645,50 @@ static void vhost_svq_flush(VhostShadowVirtqueue *svq, vhost_handle_guest_kick(svq); } } while (!vhost_svq_enable_notification(svq)); + + return ret; +} + +/** + * Poll the SVQ for device used buffers. + * + * This function race with main event loop SVQ polling, so extra + * syncthronization is needed. + * + * Return the number of descriptors read from the device. + */ +ssize_t vhost_svq_poll(VhostShadowVirtqueue *svq) +{ + int fd = event_notifier_get_fd(&svq->hdev_call); + GPollFD poll_fd = { + .fd = fd, + .events = G_IO_IN, + }; + assert(fd >= 0); + int r = g_poll(&poll_fd, 1, -1); + + if (unlikely(r < 0)) { + error_report("Cannot poll device call fd "G_POLLFD_FORMAT": (%d) %s", + poll_fd.fd, errno, g_strerror(errno)); + return -errno; + } + + if (r == 0) { + return 0; + } + + if (unlikely(poll_fd.revents & ~(G_IO_IN))) { + error_report( + "Error polling device call fd "G_POLLFD_FORMAT": revents=%d", + poll_fd.fd, poll_fd.revents); + return -1; + } + + /* + * Max return value of vhost_svq_flush is (uint16_t)-1, so it's safe to + * convert to ssize_t. + */ + return vhost_svq_flush(svq, false); } /** -- 2.27.0