From patchwork Tue Jul 11 15:52:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Hanna Czenczek X-Patchwork-Id: 13309007 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 2E871C0015E for ; Tue, 11 Jul 2023 15:53:23 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qJFfO-0000dM-TV; Tue, 11 Jul 2023 11:52:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qJFfN-0000cj-4o for qemu-devel@nongnu.org; Tue, 11 Jul 2023 11:52:41 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qJFfI-0001go-4M for qemu-devel@nongnu.org; Tue, 11 Jul 2023 11:52:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689090754; 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; bh=j+NXGThgtR1iXs69zHkEbuWF8HygYe1yvm9o6gbXmOk=; b=BLwgkrve6jMubZu3ATn1yxS3bghaANo55mH7SXWph8zsOiSshrr/i7A/S55ohCI0g/ADYg YzkjQ6CBYxxvNX8s1MgiJ4+tbooZFKwBU+1Dl5du2aIwjsTdJvIqeyyaTIp6mXQdkVrE2z xi2y4+hc83Tc7YI8T9tGPR6mIUhphSY= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-66-lIG2-1rIO5OOU7yn-qyZPg-1; Tue, 11 Jul 2023 11:52:33 -0400 X-MC-Unique: lIG2-1rIO5OOU7yn-qyZPg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D66A03814947 for ; Tue, 11 Jul 2023 15:52:32 +0000 (UTC) Received: from localhost (unknown [10.39.192.229]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 551CB1454145; Tue, 11 Jul 2023 15:52:32 +0000 (UTC) From: Hanna Czenczek To: qemu-devel@nongnu.org Cc: Hanna Czenczek , "Michael S . Tsirkin" , Stefan Hajnoczi , =?utf-8?q?Eugenio_P=C3=A9rez?= , German Maglione Subject: [PATCH 0/6] vhost-user: Add suspend/resume Date: Tue, 11 Jul 2023 17:52:22 +0200 Message-ID: <20230711155230.64277-1-hreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.133.124; envelope-from=hreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01, T_SPF_TEMPERROR=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-bounces+qemu-devel=archiver.kernel.org@nongnu.org Hi, As discussed on the previous version of the virtio-fs migration series (https://lists.nongnu.org/archive/html/qemu-devel/2023-04/msg01575.html), we currently don’t have a good way to have a vhost-user back-end fully cease all operations, including background operations. To work around this, we reset it, which is not an option for stateful devices like virtio-fs. Instead, we want the same SUSPEND/RESUME model that vhost-vdpa already has, so that we can suspend back-ends when we want them to stop doing anything (i.e. on VM stop), and resume them later (i.e. on VM resume). This series adds these vhost-user operations to the protocol and implements them in qemu. Furthermore, it has vhost-user and vhost-vdpa do roughly the same thing in their reset paths, as far as possible. That path will still remain as a fall-back if SUSPEND/RESUME is not implemented, and, given that qemu’s vhost-vdpa code currently does not make use of RESUME, it is actually always used for vhost-vdpa (to take the device out of a suspended state). Hanna Czenczek (6): vhost-user.rst: Add suspend/resume vhost-vdpa: Move vhost_vdpa_reset_status() up vhost: Do not reset suspended devices on stop vhost-user: Implement suspend/resume vhost-vdpa: Match vhost-user's status reset vhost-user: Have reset_status fall back to reset docs/interop/vhost-user.rst | 35 +++++++++++- include/hw/virtio/vhost-vdpa.h | 2 - include/hw/virtio/vhost.h | 8 +++ hw/virtio/vhost-user.c | 101 ++++++++++++++++++++++++++++++++- hw/virtio/vhost-vdpa.c | 41 ++++++------- hw/virtio/vhost.c | 8 ++- 6 files changed, 169 insertions(+), 26 deletions(-)