From patchwork Fri Oct 28 05:48:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 1695811 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=BTKYzA1C; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4MzBZs0St5z23kl for ; Fri, 28 Oct 2022 16:54:45 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ooIFI-0007KE-K2; Fri, 28 Oct 2022 01:49:32 -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 1ooIEy-00073y-3x for qemu-devel@nongnu.org; Fri, 28 Oct 2022 01:49:13 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ooIEw-0007OA-Ma for qemu-devel@nongnu.org; Fri, 28 Oct 2022 01:49:11 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1666936149; 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=PFx4uIYVvoeNX89RFe72Yy5IOaEyL665Vr3WFcQGcmE=; b=BTKYzA1CybVvSpxY+r3f5tKFIbwErmNoTGGXZgpiTEuPxkS6pMIJDwZU8tgBwWO+Q6qZFq R5lJAo2vCtuYzRkGW6hzkucf63RmCTo3k5Z0MOsTzcMY92V+Sm1sUYq4RjT0vAeRhMNyRC 9AmYGXtJxph2Kd7kiez4P+1quNwIkWs= 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-219-t6vdrjAqPJ6HwVa0k_wGmg-1; Fri, 28 Oct 2022 01:49:05 -0400 X-MC-Unique: t6vdrjAqPJ6HwVa0k_wGmg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 8839C1C07820 for ; Fri, 28 Oct 2022 05:49:05 +0000 (UTC) Received: from localhost.localdomain (ovpn-13-50.pek2.redhat.com [10.72.13.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 40604C15BA8; Fri, 28 Oct 2022 05:49:02 +0000 (UTC) From: Jason Wang To: stefanha@redhat.com, qemu-devel@nongnu.org Cc: =?utf-8?q?Eugenio_P=C3=A9rez?= , "Michael S . Tsirkin" , Jason Wang Subject: [PULL 08/26] vhost: toggle device callbacks using used event idx Date: Fri, 28 Oct 2022 13:48:17 +0800 Message-Id: <20221028054835.29674-9-jasowang@redhat.com> In-Reply-To: <20221028054835.29674-1-jasowang@redhat.com> References: <20221028054835.29674-1-jasowang@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.129.124; envelope-from=jasowang@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -25 X-Spam_score: -2.6 X-Spam_bar: -- X-Spam_report: (-2.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.515, 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: , Sender: "Qemu-devel" Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Eugenio Pérez 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. Reviewed-by: Michael S. Tsirkin Signed-off-by: Eugenio Pérez Signed-off-by: Jason Wang --- 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 a518f84..f5c0fad 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,