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 F1B23CA9EC7 for ; Sat, 2 Nov 2019 09:51:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C88D420679 for ; Sat, 2 Nov 2019 09:51:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727621AbfKBJvb (ORCPT ); Sat, 2 Nov 2019 05:51:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48050 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726670AbfKBJvb (ORCPT ); Sat, 2 Nov 2019 05:51:31 -0400 Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) (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 A302D85A07 for ; Sat, 2 Nov 2019 09:51:30 +0000 (UTC) Received: by mail-wr1-f72.google.com with SMTP id t2so7007352wri.18 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=F/4kmTglVBiuG5IX8kiCRKCTSlknKlq+DHJS3l7yRRHw42DE3CnnpfAO+/CcY4m+Az 1NaVtqBxGjpY76B6EGmAXyM2zuC+oyuRBpQInlN8M7tED930bPQ5YWBBL3pTXAcWVgF1 Zi+FcQKByXUdaZYG4Ma/LcXq3ZorDWR5VIeKKGAAlWJJ9C5fk9CPR1iAi7ztdXjq7vAX m2Z7LSxVlvswkERBoR4OvljvnvbVcA5DRLQNjEkT7A9m+9167b9XQZcsXE3ZhoYDZEqt bmOOlRsE5jDwCst9zk0ubEaPJZ1Slazr0GlQbyqrbSlCuhZHHydkJy/RkY0IL+H3Qt11 NfCQ== X-Gm-Message-State: APjAAAUPPHXuQZWf6sxJ1NM1tRbBQadgJGmb+f59MAJXS8bSD6VlTT48 OC7HKCdR69EDMtYLx91dpp+ptmsvRYltbEVI7GewNGZ+kuZ8Tbesey/Z0nxHhRyQ/euzLxJqSAR vsxYOa11+vtxdPPTOKlpgeSpo X-Received: by 2002:a5d:69c8:: with SMTP id s8mr14694472wrw.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: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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