From patchwork Tue Jul 11 15:52:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanna Czenczek X-Patchwork-Id: 13309011 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 50365EB64DC for ; Tue, 11 Jul 2023 15:53:54 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qJFfR-0000e4-5Z; Tue, 11 Jul 2023 11:52:46 -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 1qJFfP-0000db-Bz for qemu-devel@nongnu.org; Tue, 11 Jul 2023 11:52:43 -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 1qJFfN-0001hm-PT for qemu-devel@nongnu.org; Tue, 11 Jul 2023 11:52:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689090761; 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=Vp6pWpdnR3eKs5VasVSM9LNR1XXQyd2OrdGAiDMmfg4=; b=N7QVyKzNVnNHECnLHjTHNEnOh91mCwtB4oAuS4UnL7FKP/7F7s9fbcXd50TrB+SzqQVx9P 6rVdO9/LD7+ti4Fe911vGK0Ahd3HfCoyZiB+pWx75L1v7FjIOBiSN5tleSkx02a+rYFeca 1GuCoL7RHitGA560LfzydKiBmjizC6g= 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-324-_q7LsmWTOXOCPFEjzWZitA-1; Tue, 11 Jul 2023 11:52:39 -0400 X-MC-Unique: _q7LsmWTOXOCPFEjzWZitA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 46089185A78F for ; Tue, 11 Jul 2023 15:52:39 +0000 (UTC) Received: from localhost (unknown [10.39.192.229]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AE2B92166B26; Tue, 11 Jul 2023 15:52:38 +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 3/6] vhost: Do not reset suspended devices on stop Date: Tue, 11 Jul 2023 17:52:25 +0200 Message-ID: <20230711155230.64277-4-hreitz@redhat.com> In-Reply-To: <20230711155230.64277-1-hreitz@redhat.com> References: <20230711155230.64277-1-hreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 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, 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-bounces+qemu-devel=archiver.kernel.org@nongnu.org Move the `suspended` field from vhost_vdpa into the global vhost_dev struct, so vhost_dev_stop() can check whether the back-end has been suspended by `vhost_ops->vhost_dev_start(hdev, false)`. If it has, there is no need to reset it; the reset is just a fall-back to stop device operations for back-ends that do not support suspend. Unfortunately, for vDPA specifically, RESUME is not yet implemented, so when the device is re-started, we still have to do the reset to have it un-suspend. Signed-off-by: Hanna Czenczek Reviewed-by: Stefan Hajnoczi --- include/hw/virtio/vhost-vdpa.h | 2 -- include/hw/virtio/vhost.h | 8 ++++++++ hw/virtio/vhost-vdpa.c | 11 +++++++---- hw/virtio/vhost.c | 8 +++++++- 4 files changed, 22 insertions(+), 7 deletions(-) diff --git a/include/hw/virtio/vhost-vdpa.h b/include/hw/virtio/vhost-vdpa.h index e64bfc7f98..72c3686b7f 100644 --- a/include/hw/virtio/vhost-vdpa.h +++ b/include/hw/virtio/vhost-vdpa.h @@ -42,8 +42,6 @@ typedef struct vhost_vdpa { bool shadow_vqs_enabled; /* Vdpa must send shadow addresses as IOTLB key for data queues, not GPA */ bool shadow_data; - /* Device suspended successfully */ - bool suspended; /* IOVA mapping used by the Shadow Virtqueue */ VhostIOVATree *iova_tree; GPtrArray *shadow_vqs; diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h index 6a173cb9fa..69bf59d630 100644 --- a/include/hw/virtio/vhost.h +++ b/include/hw/virtio/vhost.h @@ -120,6 +120,14 @@ struct vhost_dev { uint64_t backend_cap; /* @started: is the vhost device started? */ bool started; + /** + * @suspended: Whether the vhost device is currently suspended. Set + * and reset by implementations (vhost-user, vhost-vdpa, ...), which + * are supposed to automatically suspend/resume in their + * vhost_dev_start handlers as required. Must also be cleared when + * the device is reset. + */ + bool suspended; bool log_enabled; uint64_t log_size; Error *migration_blocker; diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c index 7b7dee468e..f7fd19a203 100644 --- a/hw/virtio/vhost-vdpa.c +++ b/hw/virtio/vhost-vdpa.c @@ -858,13 +858,12 @@ static int vhost_vdpa_get_device_id(struct vhost_dev *dev, static int vhost_vdpa_reset_device(struct vhost_dev *dev) { - struct vhost_vdpa *v = dev->opaque; int ret; uint8_t status = 0; ret = vhost_vdpa_call(dev, VHOST_VDPA_SET_STATUS, &status); trace_vhost_vdpa_reset_device(dev); - v->suspended = false; + dev->suspended = false; return ret; } @@ -1278,7 +1277,7 @@ static void vhost_vdpa_suspend(struct vhost_dev *dev) if (unlikely(r)) { error_report("Cannot suspend: %s(%d)", g_strerror(errno), errno); } else { - v->suspended = true; + dev->suspended = true; return; } } @@ -1313,6 +1312,10 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started) return -1; } vhost_vdpa_set_vring_ready(dev); + if (dev->suspended) { + /* TODO: When RESUME is available, use it instead of resetting */ + vhost_vdpa_reset_status(dev); + } } else { vhost_vdpa_suspend(dev); vhost_vdpa_svqs_stop(dev); @@ -1400,7 +1403,7 @@ static int vhost_vdpa_get_vring_base(struct vhost_dev *dev, return 0; } - if (!v->suspended) { + if (!dev->suspended) { /* * Cannot trust in value returned by device, let vhost recover used * idx from guest. diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index abf0d03c8d..2e28e58da7 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -2059,7 +2059,13 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) hdev->vqs + i, hdev->vq_index + i); } - if (hdev->vhost_ops->vhost_reset_status) { + + /* + * If we failed to successfully stop the device via SUSPEND (should have + * been attempted by `vhost_dev_start(hdev, false)`), reset it to stop it. + * Stateful devices where this would be problematic must implement SUSPEND. + */ + if (!hdev->suspended && hdev->vhost_ops->vhost_reset_status) { hdev->vhost_ops->vhost_reset_status(hdev); }