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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 7B8FFC2BA19 for ; Mon, 13 Apr 2020 08:56:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5049720737 for ; Mon, 13 Apr 2020 08:56:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586768182; bh=GyaHe3+UWAOxENedBfck6FDz0o/OWfUlsXv987iJQNY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=cefO3Tnei0rYJj+CGwcdJcllieHHajNF8JW61JKPAxkaplxTcVY3ji7wNUzwGKg7D ovdsfwZjknzWeH827AS3JJwNxcZrqg5EM0QblYISLHpwer+n4dsTdOTTuYKe4IemZI PBSTyYpAi0DlA2OgwqRrRjVPOwhB9VyFkTrbuwFs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727945AbgDMI4V (ORCPT ); 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Mon, 13 Apr 2020 09:56:17 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 13 Apr 2020 09:56:17 +0100 From: Marc Zyngier To: Tianjia Zhang Cc: pbonzini@redhat.com, sean.j.christopherson@intel.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org Subject: Re: [PATCH] KVM: Optimize kvm_arch_vcpu_ioctl_run function In-Reply-To: <20200413034523.110548-1-tianjia.zhang@linux.alibaba.com> References: <20200413034523.110548-1-tianjia.zhang@linux.alibaba.com> Message-ID: <17097df45c7fe76ee3c09ac180b844d2@kernel.org> X-Sender: maz@kernel.org User-Agent: Roundcube Webmail/1.3.10 X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: tianjia.zhang@linux.alibaba.com, pbonzini@redhat.com, sean.j.christopherson@intel.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Tianjia, On 2020-04-13 04:45, Tianjia Zhang wrote: > kvm_arch_vcpu_ioctl_run() is only called in the file kvm_main.c, > where vcpu->run is the kvm_run parameter, so it has been replaced. > > Signed-off-by: Tianjia Zhang > --- > arch/x86/kvm/x86.c | 8 ++++---- > virt/kvm/arm/arm.c | 2 +- > 2 files changed, 5 insertions(+), 5 deletions(-) > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 3bf2ecafd027..70e3f4abbd4d 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -8726,18 +8726,18 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu > *vcpu, struct kvm_run *kvm_run) > r = -EAGAIN; > if (signal_pending(current)) { > r = -EINTR; > - vcpu->run->exit_reason = KVM_EXIT_INTR; > + kvm_run->exit_reason = KVM_EXIT_INTR; > ++vcpu->stat.signal_exits; > } > goto out; > } > > - if (vcpu->run->kvm_valid_regs & ~KVM_SYNC_X86_VALID_FIELDS) { > + if (kvm_run->kvm_valid_regs & ~KVM_SYNC_X86_VALID_FIELDS) { > r = -EINVAL; > goto out; > } > > - if (vcpu->run->kvm_dirty_regs) { > + if (kvm_run->kvm_dirty_regs) { > r = sync_regs(vcpu); > if (r != 0) > goto out; > @@ -8767,7 +8767,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu > *vcpu, struct kvm_run *kvm_run) > > out: > kvm_put_guest_fpu(vcpu); > - if (vcpu->run->kvm_valid_regs) > + if (kvm_run->kvm_valid_regs) > store_regs(vcpu); > post_kvm_run_save(vcpu); > kvm_sigset_deactivate(vcpu); > diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c > index 48d0ec44ad77..ab9d7966a4c8 100644 > --- a/virt/kvm/arm/arm.c > +++ b/virt/kvm/arm/arm.c > @@ -659,7 +659,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, > struct kvm_run *run) > return ret; > > if (run->exit_reason == KVM_EXIT_MMIO) { > - ret = kvm_handle_mmio_return(vcpu, vcpu->run); > + ret = kvm_handle_mmio_return(vcpu, run); > if (ret) > return ret; > } Do you have any number supporting the idea that you are optimizing anything here? Performance, code size, register pressure or any other relevant metric? Thanks, M. -- Jazz is not dead. It just smells funny...