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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 632A9C433FE for ; Fri, 3 Dec 2021 23:45:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354386AbhLCXtC (ORCPT ); Fri, 3 Dec 2021 18:49:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38726 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230023AbhLCXtB (ORCPT ); Fri, 3 Dec 2021 18:49:01 -0500 Received: from mail-pl1-x62c.google.com (mail-pl1-x62c.google.com [IPv6:2607:f8b0:4864:20::62c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E84C4C061751 for ; Fri, 3 Dec 2021 15:45:36 -0800 (PST) Received: by mail-pl1-x62c.google.com with SMTP id z6so3153346plk.6 for ; Fri, 03 Dec 2021 15:45:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=yD6g0uGUpXofVzj8NK/B5yfkrr/b2pwl08L+HXZNmGc=; b=IDYdi2gcCU7orh4FCNZ/3qn99byxzKL2xcCN/fy7149//aVjPNvsiuErNGtJG6jiTk +vcFYKfykKTbUQrJ682QgjNeEGcYx8tYLYSM4NDVmq/OJlpjLATES0QTffx7/p1ec8GW Kt5/GAxt3xPVZ++X51blLwWo5Yizh8vAQTdkRk4oAVhECQFthHqToe5+J5LzMUyOFB4g YtqAuga7Rin6skchpNJLGJ6JZNxHXNlrLHRkGhMeuIXWGJDRFiio15Vexh6+QYSG/x0s SH7gh9Sifx2PMnXScCVsPV0bH/y0XTa4a/UEZjvXYNmmCQcOeFQ8H9xkjWhkz4qze/xo O6Gw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=yD6g0uGUpXofVzj8NK/B5yfkrr/b2pwl08L+HXZNmGc=; b=vv1ronL3SsgXlhiL1Y4EaRX2nAJDSecR5Q7VopxXWBxQ97H+w8naPJ++q99AcvgFY5 LXAc9BX2bMkPel8r4pop2IgO2W2b6SV9o7Ro8ZByLlDvZRgJ3BtxZjAUDyRtl34j5BR3 z/L2M11VXISR9SYroMM9eHg5pcHEnCKx5r4l0pzbCGQN/s5ZFQUTYWg50Pd5UmZKE1Sz sXNU4R8nkBbAPqeRMFp5uzgGL5X4rDp3yemcgUwyiz4b13OZGNK7yKuh+0mf7kygTNtF +A8ES9mGG+dPjguUFc4nau7Um6zVzVAoDk/JP2R961iKLDxojweT853iv3Ypt8P+1zhA H5TA== X-Gm-Message-State: AOAM532ubTJbJB6EHgWKzpuBRz/j3sHg4r7Xn1X7EY26I3LejRw1F5EU reO+aXZeFjw00IWdf7pYf3/EO66aUciTUw== X-Google-Smtp-Source: ABdhPJwhSBTsZDHrLEJdD1LTuDAAzOLhcJfgIx6HJ3Hrk2ouSqIr1bcL3Rr3j7eKMr5wwS0weuWQ/w== X-Received: by 2002:a17:902:f24a:b0:141:c6fc:2e18 with SMTP id j10-20020a170902f24a00b00141c6fc2e18mr26414542plc.55.1638575136288; Fri, 03 Dec 2021 15:45:36 -0800 (PST) Received: from google.com (157.214.185.35.bc.googleusercontent.com. [35.185.214.157]) by smtp.gmail.com with ESMTPSA id b6sm4352949pfm.170.2021.12.03.15.45.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Dec 2021 15:45:35 -0800 (PST) Date: Fri, 3 Dec 2021 23:45:32 +0000 From: Sean Christopherson To: Vitaly Kuznetsov Cc: Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Ajay Garg , Paolo Bonzini , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , Dexuan Cui , Arnd Bergmann Subject: Re: [PATCH v2 3/8] KVM: x86: Refactor kvm_hv_flush_tlb() to reduce indentation Message-ID: References: <20211030000800.3065132-1-seanjc@google.com> <20211030000800.3065132-4-seanjc@google.com> <877ddskxfq.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <877ddskxfq.fsf@vitty.brq.redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 01, 2021, Vitaly Kuznetsov wrote: > Sean Christopherson writes: > > > Refactor the "extended" path of kvm_hv_flush_tlb() to reduce the nesting > > depth for the non-fast sparse path, and to make the code more similar to > > the extended path in kvm_hv_send_ipi(). > > > > No functional change intended. > > > > Signed-off-by: Sean Christopherson > > --- > > arch/x86/kvm/hyperv.c | 40 +++++++++++++++++++++------------------- > > 1 file changed, 21 insertions(+), 19 deletions(-) > > > > diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c > > index cf18aa1712bf..e68931ed27f6 100644 > > --- a/arch/x86/kvm/hyperv.c > > +++ b/arch/x86/kvm/hyperv.c > > @@ -1814,31 +1814,33 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool > > if (hc->var_cnt != bitmap_weight((unsigned long *)&valid_bank_mask, 64)) > > return HV_STATUS_INVALID_HYPERCALL_INPUT; > > > > - if (!hc->var_cnt && !all_cpus) > > + if (all_cpus) > > + goto do_flush; > > You could've probably done: > > if (all_cpus) { > kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH_GUEST); > goto ret_success; > } > > to get rid on the second 'all_cpus' check (and maybe even 'do_flush' > label with some extra work) below. Yeah, but the !ex path also uses all_cpus, and in general I'd prefer to keep the two flush requests bundled together.