From patchwork Wed May 19 16:28:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eugenio Perez Martin X-Patchwork-Id: 12267937 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5C1B9C433B4 for ; Wed, 19 May 2021 16:37:58 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 016B9610CD for ; Wed, 19 May 2021 16:37:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 016B9610CD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:45174 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ljPCn-000828-3v for qemu-devel@archiver.kernel.org; Wed, 19 May 2021 12:37:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34676) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ljP5f-0003j9-KR for qemu-devel@nongnu.org; Wed, 19 May 2021 12:30:35 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:56819) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ljP5d-0005W1-Tw for qemu-devel@nongnu.org; Wed, 19 May 2021 12:30:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621441833; 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=cBra4ZJJZMDqGQDXeQJipcotZaMkdrf847TS/vCHij4=; b=RFRsrTir/XUFDj45F7QklKN06TavUPoTJrwiTgVBxH32Bvaw7OfgeKTI3dxZkL9eHknXAC wqJ6MSvPywcLJEFrm/KtMA04lTKe8Ca/2Rkd924ylI6j+UAiYLViQYvjqbmnfU/xIx85yr LY4czL+DwF4UOPrGGSjNz+el0JuI1tQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-270-m1Yd4A-3NjOhezsZDz7ahw-1; Wed, 19 May 2021 12:30:31 -0400 X-MC-Unique: m1Yd4A-3NjOhezsZDz7ahw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 690621007477; Wed, 19 May 2021 16:30:30 +0000 (UTC) Received: from eperezma.remote.csb (ovpn-113-65.ams2.redhat.com [10.36.113.65]) by smtp.corp.redhat.com (Postfix) with ESMTP id D75DA5D6AC; Wed, 19 May 2021 16:30:08 +0000 (UTC) From: =?utf-8?q?Eugenio_P=C3=A9rez?= To: qemu-devel@nongnu.org Subject: [RFC v3 09/29] vhost: Avoid re-set masked notifier in shadow vq Date: Wed, 19 May 2021 18:28:43 +0200 Message-Id: <20210519162903.1172366-10-eperezma@redhat.com> In-Reply-To: <20210519162903.1172366-1-eperezma@redhat.com> References: <20210519162903.1172366-1-eperezma@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eperezma@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.133.124; envelope-from=eperezma@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.39, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Parav Pandit , "Michael S. Tsirkin" , Jason Wang , Juan Quintela , Markus Armbruster , virtualization@lists.linux-foundation.org, Harpreet Singh Anand , Xiao W Wang , Stefan Hajnoczi , Eli Cohen , Michael Lilja , Stefano Garzarella Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Since all the shadow virtqueue device is done in software, we can avoid the write syscall. Signed-off-by: Eugenio Pérez --- hw/virtio/vhost-shadow-virtqueue.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index 7d76e271a5..c22acb4605 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -35,6 +35,9 @@ typedef struct VhostShadowVirtqueue { /* (Possible) masked notifier */ struct { EventNotifier *n; + + /* Avoid re-sending signals */ + bool signaled; } masked_notifier; /* Virtio queue shadowing */ @@ -70,7 +73,8 @@ static void vhost_shadow_vq_handle_call_no_test(EventNotifier *n) unsigned n = virtio_get_queue_index(svq->vq); virtio_queue_invalidate_signalled_used(svq->vdev, n); virtio_notify_irqfd(svq->vdev, svq->vq); - } else { + } else if (!svq->masked_notifier.signaled) { + svq->masked_notifier.signaled = true; event_notifier_set(svq->masked_notifier.n); } } @@ -93,6 +97,7 @@ static void vhost_shadow_vq_handle_call(EventNotifier *n) */ void vhost_shadow_vq_mask(VhostShadowVirtqueue *svq, EventNotifier *masked) { + svq->masked_notifier.signaled = false; svq->masked_notifier.n = masked; }