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 2C249C001DC for ; Thu, 27 Jul 2023 12:40:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230455AbjG0Mkv (ORCPT ); Thu, 27 Jul 2023 08:40:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43862 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231622AbjG0Mkv (ORCPT ); Thu, 27 Jul 2023 08:40:51 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F3B57E44; Thu, 27 Jul 2023 05:40:49 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7489D61E61; Thu, 27 Jul 2023 12:40:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CAD9AC433C8; Thu, 27 Jul 2023 12:40:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690461648; bh=GuUn7Qiz7VlihN9V+lWXsCHtNZx1opVL1pqDW0CmmGE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=m4Zirj1gKc9tNlyrRCZuIT8igAPw85Xg5ys5NjJ5Q35IBkHX8oEM1YoQIwFxapEYq eoVftHKHAOUVaZTf+JgeLUgfFiW7xKfVfPhRIGfm7HNMaZ08aCuevB6QsbsMjzm54l MULu3nsUpoqL6X9AsxSiuCEv0YdMV3f4M5DMi9xxYBrK6h5plOp+5r3qivn/1hyQfO WX2+ob/tNCXZ61LT2uRgOk8hJit3HLb6mlQSieLjs2eJSjsSbbNYSW1sQ5bly1IEmz uysVQXcpzOt1k/PDwfmdiFCcXtItNdFqVCtEf4HM/6EcJYi1cNW1row0ghxskQRBAm nlr6M/nP8z2Pw== Received: from [104.132.45.102] (helo=wait-a-minute.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1qP0IQ-00HMEO-FH; Thu, 27 Jul 2023 13:40:46 +0100 Date: Thu, 27 Jul 2023 13:40:46 +0100 Message-ID: <87pm4dr0hd.wl-maz@kernel.org> From: Marc Zyngier To: Raghavendra Rao Ananta Cc: Oliver Upton , James Morse , Suzuki K Poulose , Paolo Bonzini , Sean Christopherson , Huacai Chen , Zenghui Yu , Anup Patel , Atish Patra , Jing Zhang , Reiji Watanabe , Colton Lewis , David Matlack , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-mips@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Gavin Shan Subject: Re: [PATCH v7 07/12] KVM: arm64: Implement __kvm_tlb_flush_vmid_range() In-Reply-To: <20230722022251.3446223-8-rananta@google.com> References: <20230722022251.3446223-1-rananta@google.com> <20230722022251.3446223-8-rananta@google.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/28.2 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 104.132.45.102 X-SA-Exim-Rcpt-To: rananta@google.com, oliver.upton@linux.dev, james.morse@arm.com, suzuki.poulose@arm.com, pbonzini@redhat.com, seanjc@google.com, chenhuacai@kernel.org, yuzenghui@huawei.com, anup@brainfault.org, atishp@atishpatra.org, jingzhangos@google.com, reijiw@google.com, coltonlewis@google.com, dmatlack@google.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-mips@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, gshan@redhat.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Sat, 22 Jul 2023 03:22:46 +0100, Raghavendra Rao Ananta wrote: > > Define __kvm_tlb_flush_vmid_range() (for VHE and nVHE) > to flush a range of stage-2 page-tables using IPA in one go. > If the system supports FEAT_TLBIRANGE, the following patches > would conviniently replace global TLBI such as vmalls12e1is > in the map, unmap, and dirty-logging paths with ripas2e1is > instead. > > Signed-off-by: Raghavendra Rao Ananta > Reviewed-by: Gavin Shan > --- > arch/arm64/include/asm/kvm_asm.h | 3 +++ > arch/arm64/kvm/hyp/nvhe/hyp-main.c | 11 +++++++++++ > arch/arm64/kvm/hyp/nvhe/tlb.c | 30 ++++++++++++++++++++++++++++++ > arch/arm64/kvm/hyp/vhe/tlb.c | 27 +++++++++++++++++++++++++++ > 4 files changed, 71 insertions(+) > > diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h > index 7d170aaa2db4..2c27cb8cf442 100644 > --- a/arch/arm64/include/asm/kvm_asm.h > +++ b/arch/arm64/include/asm/kvm_asm.h > @@ -70,6 +70,7 @@ enum __kvm_host_smccc_func { > __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa, > __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa_nsh, > __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid, > + __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_range, > __KVM_HOST_SMCCC_FUNC___kvm_flush_cpu_context, > __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntvoff, > __KVM_HOST_SMCCC_FUNC___vgic_v3_read_vmcr, > @@ -229,6 +230,8 @@ extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, > extern void __kvm_tlb_flush_vmid_ipa_nsh(struct kvm_s2_mmu *mmu, > phys_addr_t ipa, > int level); > +extern void __kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu, > + phys_addr_t start, unsigned long pages); > extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu); > > extern void __kvm_timer_set_cntvoff(u64 cntvoff); > diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c > index a169c619db60..857d9bc04fd4 100644 > --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c > +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c > @@ -135,6 +135,16 @@ static void handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context *host_ctx > __kvm_tlb_flush_vmid_ipa_nsh(kern_hyp_va(mmu), ipa, level); > } > > +static void > +handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context *host_ctxt) > +{ > + DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); > + DECLARE_REG(phys_addr_t, start, host_ctxt, 2); > + DECLARE_REG(unsigned long, pages, host_ctxt, 3); > + > + __kvm_tlb_flush_vmid_range(kern_hyp_va(mmu), start, pages); > +} > + > static void handle___kvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt) > { > DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); > @@ -327,6 +337,7 @@ static const hcall_t host_hcall[] = { > HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa), > HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa_nsh), > HANDLE_FUNC(__kvm_tlb_flush_vmid), > + HANDLE_FUNC(__kvm_tlb_flush_vmid_range), > HANDLE_FUNC(__kvm_flush_cpu_context), > HANDLE_FUNC(__kvm_timer_set_cntvoff), > HANDLE_FUNC(__vgic_v3_read_vmcr), > diff --git a/arch/arm64/kvm/hyp/nvhe/tlb.c b/arch/arm64/kvm/hyp/nvhe/tlb.c > index b9991bbd8e3f..09347111c2cd 100644 > --- a/arch/arm64/kvm/hyp/nvhe/tlb.c > +++ b/arch/arm64/kvm/hyp/nvhe/tlb.c > @@ -182,6 +182,36 @@ void __kvm_tlb_flush_vmid_ipa_nsh(struct kvm_s2_mmu *mmu, > __tlb_switch_to_host(&cxt); > } > > +void __kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu, > + phys_addr_t start, unsigned long pages) > +{ > + struct tlb_inv_context cxt; > + unsigned long stride; > + > + /* > + * Since the range of addresses may not be mapped at > + * the same level, assume the worst case as PAGE_SIZE > + */ > + stride = PAGE_SIZE; > + start = round_down(start, stride); > + > + /* Switch to requested VMID */ > + __tlb_switch_to_guest(mmu, &cxt, false); > + > + __flush_tlb_range_op(ipas2e1is, start, pages, stride, 0, 0, false); I really think we need an abstraction here. All this ASID and user nonsense shouldn't appear here. Something such as __flush_s2_tlb_range_op(), which would pass the correct parameters that this code shouldn't have to worry about. I'm also a bit concerned by the fact we completely lose the level here. This is a massive fast-path for the CPU, and we don't make use of it. It'd be worth thinking of how we can make use of it if at all possible... > + > + dsb(ish); > + __tlbi(vmalle1is); > + dsb(ish); > + isb(); > + > + /* See the comment in __kvm_tlb_flush_vmid_ipa() */ > + if (icache_is_vpipt()) > + icache_inval_all_pou(); > + > + __tlb_switch_to_host(&cxt); Another thing is that it is high time that some of this call gets refactored. All these helpers are basically the same sequence, only differing by a couple of lines. Not something we need to do immediately, but eventually we'll have to bite the bullet. M. -- Without deviation from the norm, progress is not possible.