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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 C92B8C43603 for ; Tue, 17 Dec 2019 16:31:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9BE5421582 for ; Tue, 17 Dec 2019 16:31:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hNeTp5Gk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728707AbfLQQby (ORCPT ); Tue, 17 Dec 2019 11:31:54 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:31982 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728465AbfLQQbx (ORCPT ); Tue, 17 Dec 2019 11:31:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576600312; 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=p4Hn2/T4wztJ+c4sVZ6jA7HB4xZQZPe/kIKj1uFgRVk=; b=hNeTp5GkdBEOR7hIwvl+ypDHOC1HcZ99wV69r7OSBGcpKnLoy79v+NfGAdvv8uk6bTs+sI rMlD0eSaUKrC31oLqUyAp+iBAsSirS0XlPSNgX4bzsxqh0U6uCoyWoWc2PNJbBHX+eWZvH pxrRYBk2toAk4RHLPCTFvY2U+fiuBfI= Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-168-yI00vp-CPyO38eBUCfzmug-1; Tue, 17 Dec 2019 11:31:51 -0500 X-MC-Unique: yI00vp-CPyO38eBUCfzmug-1 Received: by mail-wr1-f72.google.com with SMTP id d8so4906976wrq.12 for ; Tue, 17 Dec 2019 08:31:51 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=p4Hn2/T4wztJ+c4sVZ6jA7HB4xZQZPe/kIKj1uFgRVk=; b=YKcBG5M0LltC0Y0cw0TsBimrf/1MHTamcr82KLkYkmW0DPXfogqxsm0Q0RMiV8KXuL PDU68VBHwsIP0y9HI+/H16gjUZOsaM9exh4khmELhjDe6VoVMAxKU8oPzVMRbygmvYnF fgomkDgCGbFvGNs3JSFhHwgVzPbk/3+KgA49npzytgY3cRcCMxf4jGYL6fFXMucPpTDI 8iMW9PbW4IqB9Rs10+oUN0LLx03B4MRLJhb6uo7YLNeLA7XO3OdW4KGn+711SCy++oTN 31q9Cxg7Z3iwUwbkHAKDT1MbBCImXsjdJDPwscpvJ6bQHZBSlABVHG+zJl6kKPD0o5FR /54w== X-Gm-Message-State: APjAAAWswfdgoreplxIODALvvyhFUhzxJtAVTMIBeAsi9i6d3SrmaIx0 QXEg+TF8+HuhdwoZW6/e61Xrk9u9vpGu1txVCFAERv6opeTUxjasBK/+7BzwW1LqHvVRCvFr76W F1U7RoewCYu4g/rc08I5Bxllk X-Received: by 2002:a7b:cd84:: with SMTP id y4mr6245436wmj.57.1576600309957; Tue, 17 Dec 2019 08:31:49 -0800 (PST) X-Google-Smtp-Source: APXvYqyC2rukHVDQgKq/ZtQIpGm8enAFSLAsGkp7zQE3V9/knw3xd0UFSkx6c2y3sZBvaw/ULjXKEw== X-Received: by 2002:a7b:cd84:: with SMTP id y4mr6245415wmj.57.1576600309736; Tue, 17 Dec 2019 08:31:49 -0800 (PST) Received: from ?IPv6:2001:b07:6468:f312:503f:4ffc:fc4a:f29a? ([2001:b07:6468:f312:503f:4ffc:fc4a:f29a]) by smtp.gmail.com with ESMTPSA id h2sm27209915wrt.45.2019.12.17.08.31.48 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 17 Dec 2019 08:31:49 -0800 (PST) Subject: Re: [PATCH RFC 04/15] KVM: Implement ring-based dirty memory tracking To: Peter Xu Cc: Christophe de Dinechin , Christophe de Dinechin , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Sean Christopherson , "Dr . David Alan Gilbert" , Vitaly Kuznetsov References: <20191129213505.18472-1-peterx@redhat.com> <20191129213505.18472-5-peterx@redhat.com> <20191213202324.GI16429@xz-x1> <20191217153837.GC7258@xz-x1> From: Paolo Bonzini Message-ID: Date: Tue, 17 Dec 2019 17:31:48 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.1.1 MIME-Version: 1.0 In-Reply-To: <20191217153837.GC7258@xz-x1> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 17/12/19 16:38, Peter Xu wrote: > There's still time to persuade me to going back to it. :) > > (Though, yes I still like current solution... if we can get rid of the > only kvmgt ugliness, we can even throw away the per-vm ring with its > "extra" 4k page. Then I suppose it'll be even harder to persuade me :) Actually that's what convinced me in the first place, so let's absolutely get rid of both the per-VM ring and the union. Kevin and Alex have answered and everybody seems to agree. Paolo