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 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,URIBL_BLOCKED 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 87A98C11F68 for ; Fri, 2 Jul 2021 15:12:54 +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 26B3B61410 for ; Fri, 2 Jul 2021 15:12:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 26B3B61410 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]:34648 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lzKqb-0000c9-7S for qemu-devel@archiver.kernel.org; Fri, 02 Jul 2021 11:12:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36506) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lzKpr-0007O0-Tq for qemu-devel@nongnu.org; Fri, 02 Jul 2021 11:12:07 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:52342) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lzKpo-0001so-Mo for qemu-devel@nongnu.org; Fri, 02 Jul 2021 11:12:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1625238723; 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: in-reply-to:in-reply-to:references:references; bh=2ItVkG8dPy9/F0vNCKi7jvhH2WVxB80xoa5rCQhtC34=; b=N2WNNvS2uCIq9fa6Pp2jEArJkShzU0+yl+wgEFZ9L7WHLK5/cIiQgqeiMG8mpqLGzjX7/X /97ur7jmjFPYMlDFE4BvMLfFvR4eNT4uWBZmM/zfQc7lpg7rsHbIjAczUeeQk560hGnetk ZJkGemDwtMaH0yLXrHeBzEZZYB2WPIk= Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-326-4ZpqYdrHP_WCqp6DDiqu4g-1; Fri, 02 Jul 2021 11:12:01 -0400 X-MC-Unique: 4ZpqYdrHP_WCqp6DDiqu4g-1 Received: by mail-ed1-f69.google.com with SMTP id z5-20020a05640235c5b0290393974bcf7eso5226738edc.2 for ; Fri, 02 Jul 2021 08:12:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=2ItVkG8dPy9/F0vNCKi7jvhH2WVxB80xoa5rCQhtC34=; b=e4kEYimuhCfu0cdXgYi9Rbec35G9jREPNxaeTffZkiW+bbI7qGwPVs5+shO557Qpkc oDvQ/FhDjnODcdPmrnzykpTQwGVQRsQwUncpNvfPV80MjNJ87G8GCVWSYWymGPW0nJM/ Zfl6jHmJ+NwXUyJRr+FfQ1uncU9X0+mBfHkHuO0gi0uoc6YFcBO/hNXVuih1wO/EMdTu IeRLewH2cGVNHYbLMLGJ2jh4ufn/k+tsT9l0yBvshnCrW0Be1NhPNj4BxVexEFjCYDO4 paKgmiPyUVwjWR8Vj3i7yiTJ/0bz0K8N6vRAxCPku9Akoh9Nd0jE3yU5Or/UnCrMzUbR 5lDQ== X-Gm-Message-State: AOAM5329LBhWAV9OvrxVGfIvv7ZLsj93NzjKg65YKa7ROKuJUKk1SS1r RDUBGfkVl3EpSPf7Yoeq/97ztsvUNiXmPaRoBKeFqtR1+67dIPhwstLmfcbwwfSKtPv8EiOCuoc bbXIrbh0iXt1yTn8= X-Received: by 2002:a17:906:a2da:: with SMTP id by26mr196567ejb.152.1625238720754; Fri, 02 Jul 2021 08:12:00 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxyJfJmUaNrmFkBM79FsJufflw7L0QrjiOX6Sx+DHIKNaL8ktLsDUcQP+07bLV70R67rL9NUA== X-Received: by 2002:a17:906:a2da:: with SMTP id by26mr196538ejb.152.1625238720447; Fri, 02 Jul 2021 08:12:00 -0700 (PDT) Received: from redhat.com ([2.55.4.39]) by smtp.gmail.com with ESMTPSA id yd25sm1116696ejb.114.2021.07.02.08.11.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 02 Jul 2021 08:11:59 -0700 (PDT) Date: Fri, 2 Jul 2021 11:11:56 -0400 From: "Michael S. Tsirkin" To: Pavel Dovgalyuk Subject: Re: [PATCH] replay: improve determinism of virtio-net Message-ID: <20210702111128-mutt-send-email-mst@kernel.org> References: <162125666020.1252655.9997723318921206001.stgit@pasha-ThinkPad-X280> MIME-Version: 1.0 In-Reply-To: <162125666020.1252655.9997723318921206001.stgit@pasha-ThinkPad-X280> Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mst@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=170.10.133.124; envelope-from=mst@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=-0.377, 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: pbonzini@redhat.com, jasowang@redhat.com, alex.bennee@linaro.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, May 17, 2021 at 04:04:20PM +0300, Pavel Dovgalyuk wrote: > virtio-net device uses bottom halves for callbacks. > These callbacks should be deterministic, because they affect VM state. > This patch replaces BH invocations with corresponding replay functions, > making them deterministic in record/replay mode. > This patch also disables guest announce timers for record/replay, > because they break correct loadvm in deterministic mode. > > Signed-off-by: Pavel Dovgalyuk Seems to make sense but clearly Jason's area. Jason? > --- > hw/net/virtio-net.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index 6b7e8dd04e..e876363236 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -44,6 +44,7 @@ > #include "hw/pci/pci.h" > #include "net_rx_pkt.h" > #include "hw/virtio/vhost.h" > +#include "sysemu/replay.h" > > #define VIRTIO_NET_VM_VERSION 11 > > @@ -394,7 +395,7 @@ static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status) > timer_mod(q->tx_timer, > qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout); > } else { > - qemu_bh_schedule(q->tx_bh); > + replay_bh_schedule_event(q->tx_bh); > } > } else { > if (q->tx_timer) { > @@ -2546,7 +2547,7 @@ static void virtio_net_handle_tx_bh(VirtIODevice *vdev, VirtQueue *vq) > return; > } > virtio_queue_set_notification(vq, 0); > - qemu_bh_schedule(q->tx_bh); > + replay_bh_schedule_event(q->tx_bh); > } > > static void virtio_net_tx_timer(void *opaque) > @@ -2602,7 +2603,7 @@ static void virtio_net_tx_bh(void *opaque) > /* If we flush a full burst of packets, assume there are > * more coming and immediately reschedule */ > if (ret >= n->tx_burst) { > - qemu_bh_schedule(q->tx_bh); > + replay_bh_schedule_event(q->tx_bh); > q->tx_waiting = 1; > return; > } > @@ -2616,7 +2617,7 @@ static void virtio_net_tx_bh(void *opaque) > return; > } else if (ret > 0) { > virtio_queue_set_notification(q->tx_vq, 0); > - qemu_bh_schedule(q->tx_bh); > + replay_bh_schedule_event(q->tx_bh); > q->tx_waiting = 1; > } > } > @@ -3206,6 +3207,10 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) > n->host_features |= (1ULL << VIRTIO_NET_F_MTU); > } > > + if (replay_mode != REPLAY_MODE_NONE) { > + n->host_features &= ~(1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE); > + } > + > if (n->net_conf.duplex_str) { > if (strncmp(n->net_conf.duplex_str, "half", 5) == 0) { > n->net_conf.duplex = DUPLEX_HALF;