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 84AEAC4332F for ; Thu, 20 Oct 2022 17:01:38 +0000 (UTC) Received: from localhost ([::1]:55798 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1olYuv-0006wV-El for qemu-devel@archiver.kernel.org; Thu, 20 Oct 2022 13:01:17 -0400 Received: from [::1] (helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1olYtg-0000Xd-LX for qemu-devel@archiver.kernel.org; Thu, 20 Oct 2022 12:59:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58024) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1olXrS-0006Pz-Mk for qemu-devel@nongnu.org; Thu, 20 Oct 2022 11:53:35 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:20811) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1olXrD-00065Q-7q for qemu-devel@nongnu.org; Thu, 20 Oct 2022 11:53:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1666281197; 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=5wxZEbQecvH0VDpYnnCfOiDlaLCxR12ly1QlIET+pvw=; b=KvDGFmsWpDf5R772+queO7igBTwrQGfz+KjOptu6fDxY5hR/WigLX7K3CsxJMp9seGF8t/ hjM7AlK79foP3b+4wgh6i+kENToBvaDJiHASCi3D6Lcox8JJh/wyC8td2NWNXBLm833NV0 Q/1uRXvh1dvqHZkB5ThciF4gp+ToZRg= 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-463-bTDuVD0bMF2gN0OHYXojmQ-1; Thu, 20 Oct 2022 11:53:15 -0400 X-MC-Unique: bTDuVD0bMF2gN0OHYXojmQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id BAE0E10115F5; Thu, 20 Oct 2022 15:53:13 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.192.230]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7FBE940CA41E; Thu, 20 Oct 2022 15:53:11 +0000 (UTC) From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= To: qemu-devel@nongnu.org Cc: Liuxiangdong , Parav Pandit , Harpreet Singh Anand , "Michael S. Tsirkin" , Laurent Vivier , Zhu Lingshan , Gautam Dawar , Eli Cohen , Stefano Garzarella , Cindy Lu , Jason Wang , Si-Wei Liu Subject: [PATCH 2/4] vhost: toggle device callbacks using used event idx Date: Thu, 20 Oct 2022 17:52:49 +0200 Message-Id: <20221020155251.398735-3-eperezma@redhat.com> In-Reply-To: <20221020155251.398735-1-eperezma@redhat.com> References: <20221020155251.398735-1-eperezma@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Received-SPF: pass client-ip=170.10.129.124; envelope-from=eperezma@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.251, 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_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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" Actually use the new field of the used ring and tell the device if SVQ wants to be notified. The code is not reachable at the moment. Signed-off-by: Eugenio Pérez --- hw/virtio/vhost-shadow-virtqueue.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index a518f84772..f5c0fad3fc 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -369,15 +369,27 @@ static bool vhost_svq_more_used(VhostShadowVirtqueue *svq) */ static bool vhost_svq_enable_notification(VhostShadowVirtqueue *svq) { - svq->vring.avail->flags &= ~cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT); - /* Make sure the flag is written before the read of used_idx */ + if (virtio_vdev_has_feature(svq->vdev, VIRTIO_RING_F_EVENT_IDX)) { + uint16_t *used_event = (uint16_t *)&svq->vring.avail->ring[svq->vring.num]; + *used_event = svq->shadow_used_idx; + } else { + svq->vring.avail->flags &= ~cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT); + } + + /* Make sure the event is enabled before the read of used_idx */ smp_mb(); return !vhost_svq_more_used(svq); } static void vhost_svq_disable_notification(VhostShadowVirtqueue *svq) { - svq->vring.avail->flags |= cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT); + /* + * No need to disable notification in the event idx case, since used event + * index is already an index too far away. + */ + if (!virtio_vdev_has_feature(svq->vdev, VIRTIO_RING_F_EVENT_IDX)) { + svq->vring.avail->flags |= cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT); + } } static uint16_t vhost_svq_last_desc_of_chain(const VhostShadowVirtqueue *svq, -- 2.31.1