From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH V4 2/15] KVM/MMU: Add tlb flush with range helper function Date: Sun, 14 Oct 2018 10:27:34 +0100 Message-ID: <20181014092734.GV30658@n2100.armlinux.org.uk> References: <20181013145406.4911-1-Tianyu.Lan@microsoft.com> <20181013145406.4911-3-Tianyu.Lan@microsoft.com> <4D709C3A-A91C-4CA7-922A-E77618EF21B4@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Thomas Gleixner Cc: Liran Alon , linux-mips@linux-mips.org, linux@armlinux.org, kvm@vger.kernel.org, rkrcmar@redhat.com, catalin.marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, paulus@ozlabs.org, hpa@zytor.com, kys@microsoft.com, kvmarm@lists.cs.columbia.edu, lantianyu1986@gmail.com, sthemmin@microsoft.com, mpe@ellerman.id.au, x86@kernel.org, michael.h.kelley@microsoft.com, mingo@redhat.com, benh@kernel.crashing.org, jhogan@kernel.org, Lan Tianyu , marc.zyngier@arm.com, haiyangz@microsoft.com, kvm-ppc@vger.kernel.org, devel@linuxdriverproject.org, linux-arm-kernel@lists.infradead.org, christoffer.dall@arm.com, ralf@linux-mips.org, paul.burton@mips.com, pbonzini@redhat.com, vkuznets@redhat.com, linuxppc-dev@lists.ozlabs.org List-Id: kvmarm@lists.cs.columbia.edu On Sun, Oct 14, 2018 at 10:16:56AM +0200, Thomas Gleixner wrote: > On Sun, 14 Oct 2018, Liran Alon wrote: > > > On 13 Oct 2018, at 17:53, lantianyu1986@gmail.com wrote: > > > > > > From: Lan Tianyu > > > > > > This patch is to add wrapper functions for tlb_remote_flush_with_range > > > callback. > > > > > > Signed-off-by: Lan Tianyu > > > --- > > > Change sicne V3: > > > Remove code of updating "tlbs_dirty" > > > Change since V2: > > > Fix comment in the kvm_flush_remote_tlbs_with_range() > > > --- > > > arch/x86/kvm/mmu.c | 40 ++++++++++++++++++++++++++++++++++++++++ > > > 1 file changed, 40 insertions(+) > > > > > > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > > > index c73d9f650de7..ff656d85903a 100644 > > > --- a/arch/x86/kvm/mmu.c > > > +++ b/arch/x86/kvm/mmu.c > > > @@ -264,6 +264,46 @@ static void mmu_spte_set(u64 *sptep, u64 spte); > > > static union kvm_mmu_page_role > > > kvm_mmu_calc_root_page_role(struct kvm_vcpu *vcpu); > > > > > > + > > > +static inline bool kvm_available_flush_tlb_with_range(void) > > > +{ > > > + return kvm_x86_ops->tlb_remote_flush_with_range; > > > +} > > > > Seems that kvm_available_flush_tlb_with_range() is not used in this patch… > > What's wrong with that? > > It provides the implementation and later patches make use of it. It's a > sensible way to split patches into small, self contained entities. >>From what I can see of the patches that follow _this_ patch in the series, this function remains unused. So, not only is it not used in this patch, it's not used in this series. I think the real question that needs asking is - what is the plan for this function, and when will it be used? -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up