From patchwork Fri Oct 28 05:48:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 13023099 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 AF179FA3742 for ; Fri, 28 Oct 2022 05:53:07 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ooIFJ-0007KO-6E; Fri, 28 Oct 2022 01:49:33 -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 1ooIF0-00074M-98 for qemu-devel@nongnu.org; Fri, 28 Oct 2022 01:49:14 -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 1ooIEy-0007QW-SV for qemu-devel@nongnu.org; Fri, 28 Oct 2022 01:49:14 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1666936152; 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=6+zIHU8uIHbt1gV6GPyuXQtTL2YzBpGeO7d6z9rEo1w=; b=Vub5rqDfIEfA5ZZ7sA+smfIzsD34pKJY0S7cNizCw4HbxfPbSItF4rhwJTEI/VJoXzn9e5 0XfzEET24s25leyKD/5RKQTJef3j6cqu4L6ITWxgLAieoMT6qjezXrQ4H+0XxR1iIK86Wb zZgcUVYNU/k4uP3CT0kB4jFWipoCD3I= 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-657-J5qa564FPe6D6hEOwCm5Zw-1; Fri, 28 Oct 2022 01:49:08 -0400 X-MC-Unique: J5qa564FPe6D6hEOwCm5Zw-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 836A0185A78F for ; Fri, 28 Oct 2022 05:49:08 +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 3AB1CC15BA8; Fri, 28 Oct 2022 05:49:05 +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 09/26] vhost: use avail event idx on vhost_svq_kick Date: Fri, 28 Oct 2022 13:48:18 +0800 Message-Id: <20221028054835.29674-10-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+qemu-devel=archiver.kernel.org@nongnu.org From: Eugenio Pérez So SVQ code knows if an event is needed. 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 | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index f5c0fad..f306ebe 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -218,12 +218,22 @@ static bool vhost_svq_add_split(VhostShadowVirtqueue *svq, static void vhost_svq_kick(VhostShadowVirtqueue *svq) { + bool needs_kick; + /* * We need to expose the available array entries before checking the used * flags */ smp_mb(); - if (svq->vring.used->flags & VRING_USED_F_NO_NOTIFY) { + + if (virtio_vdev_has_feature(svq->vdev, VIRTIO_RING_F_EVENT_IDX)) { + uint16_t avail_event = *(uint16_t *)(&svq->vring.used->ring[svq->vring.num]); + needs_kick = vring_need_event(avail_event, svq->shadow_avail_idx, svq->shadow_avail_idx - 1); + } else { + needs_kick = !(svq->vring.used->flags & VRING_USED_F_NO_NOTIFY); + } + + if (!needs_kick) { return; }