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=-2.3 required=3.0 tests=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 1402CCA9ED1 for ; Sat, 2 Nov 2019 09:51:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EA51021726 for ; Sat, 2 Nov 2019 09:51:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727500AbfKBJvb (ORCPT ); Sat, 2 Nov 2019 05:51:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48052 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727091AbfKBJvb (ORCPT ); Sat, 2 Nov 2019 05:51:31 -0400 Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id ADD088665A for ; Sat, 2 Nov 2019 09:51:30 +0000 (UTC) Received: by mail-wr1-f71.google.com with SMTP id s9so7021439wrw.23 for ; Sat, 02 Nov 2019 02:51:30 -0700 (PDT) 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:openpgp:message-id :date:user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=l8qAdWRObZ9diNurmyFj32RwamTbc6O7HnqjMAubn+g=; b=uZoVkhuU0ZqdBj+y0I5He1wrz2vMEWAGNPJqDPjXf+Do0VRQPdgYSZ8in/XUEqgVy+ gkVs95bqlW87sNGmZE91/zfgHk7f8FDJIMkb6YSlv8yHuIvPaoAsj/c+crMx/iJWOQPS 8ASSS+iMnz4FsaANRoUgGgs/aHXkeWy0ccLbkov7ULcWsQjIW04uQMfyKObhF5jx7TSw sG13Rx6u94Cjl1cB340V3o0ncbshssUU1H9l2/U71IIA10vrIzziyAgNDGvVszDsgpj+ uEphT9GOTjz+FzXazXZ+dc5pudQVtp55lnVX4injYJDqUnebcUudbC/35ae57g32i+xP 5XmA== X-Gm-Message-State: APjAAAVybZE73yQE+erAp2bj7q+0wo6Y2q6kwj4PnVHboqYjyuTF/PYK t9NhIMX/MGuwkRN/63yN2EBs32y6JGVzFZueF11hCrs5D6MB15P4kTWNJZtVph0BM20v/TJ6aQb Ke/qmfK22SliO X-Received: by 2002:a5d:69c8:: with SMTP id s8mr14694477wrw.167.1572688289338; Sat, 02 Nov 2019 02:51:29 -0700 (PDT) X-Google-Smtp-Source: APXvYqw2zf793oOTw8eZP9mFlJz05v9GK0WJFS03MxDK0c2oafYGNsvzIm/OUePbHZdoEfHUhIp0ag== X-Received: by 2002:a5d:69c8:: with SMTP id s8mr14694452wrw.167.1572688289015; Sat, 02 Nov 2019 02:51:29 -0700 (PDT) Received: from [192.168.42.35] (mob-31-159-163-247.net.vodafone.it. [31.159.163.247]) by smtp.gmail.com with ESMTPSA id d20sm14673270wra.4.2019.11.02.02.51.26 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 02 Nov 2019 02:51:28 -0700 (PDT) Subject: Re: [PATCH v4 03/17] kvm: x86: Introduce APICv deactivate bits To: "Suthikulpanit, Suravee" , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" Cc: "rkrcmar@redhat.com" , "joro@8bytes.org" , "vkuznets@redhat.com" , "rkagan@virtuozzo.com" , "graf@amazon.com" , "jschoenh@amazon.de" , "karahmed@amazon.de" , "rimasluk@amazon.com" , "Grimm, Jon" References: <1572648072-84536-1-git-send-email-suravee.suthikulpanit@amd.com> <1572648072-84536-4-git-send-email-suravee.suthikulpanit@amd.com> From: Paolo Bonzini Openpgp: preference=signencrypt Message-ID: Date: Sat, 2 Nov 2019 10:51:15 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <1572648072-84536-4-git-send-email-suravee.suthikulpanit@amd.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 01/11/19 23:41, Suthikulpanit, Suravee wrote: > + unsigned long apicv_deact_msk; No abbrev fld names. :) I can change this to something like apicv_inhibit_reasons if there are no other issues (and likewise s/APICV_DEACT_BIT_/APICV_INHIBIT_REASON_/). > > +bool kvm_apicv_activated(struct kvm *kvm) > +{ > + return (READ_ONCE(kvm->arch.apicv_deact_msk) == 0); > +} Using READ_ONCE introduces a risk of races. I'll check during a more thorough review if it's worth introducing separate kvm_apicv_active and kvm_apicv_active_nolock functions. Paolo