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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 9DBE2C433B4 for ; Thu, 15 Apr 2021 11:50:52 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id ED4B1613C3 for ; Thu, 15 Apr 2021 11:50:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ED4B1613C3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 600914B6C6; Thu, 15 Apr 2021 07:50:51 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id TktgcNnfQCka; Thu, 15 Apr 2021 07:50:50 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 26CCC4B72D; Thu, 15 Apr 2021 07:50:50 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 9037F4B721 for ; Thu, 15 Apr 2021 07:50:48 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HEbTZlRJSToB for ; Thu, 15 Apr 2021 07:50:47 -0400 (EDT) Received: from szxga04-in.huawei.com (szxga04-in.huawei.com [45.249.212.190]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 9F4C34B6A5 for ; Thu, 15 Apr 2021 07:50:46 -0400 (EDT) Received: from DGGEMS407-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4FLcz75fP7zpYWg; Thu, 15 Apr 2021 19:47:47 +0800 (CST) Received: from DESKTOP-TMVL5KK.china.huawei.com (10.174.187.128) by DGGEMS407-HUB.china.huawei.com (10.3.19.207) with Microsoft SMTP Server id 14.3.498.0; Thu, 15 Apr 2021 19:50:36 +0800 From: Yanan Wang To: Marc Zyngier , Will Deacon , "Quentin Perret" , Alexandru Elisei , , , , Subject: [PATCH v5 2/6] KVM: arm64: Move D-cache flush to the fault handlers Date: Thu, 15 Apr 2021 19:50:28 +0800 Message-ID: <20210415115032.35760-3-wangyanan55@huawei.com> X-Mailer: git-send-email 2.8.4.windows.1 In-Reply-To: <20210415115032.35760-1-wangyanan55@huawei.com> References: <20210415115032.35760-1-wangyanan55@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.187.128] X-CFilter-Loop: Reflected Cc: Catalin Marinas X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu We currently uniformly permorm CMOs of D-cache and I-cache in function user_mem_abort before calling the fault handlers. If we get concurrent guest faults(e.g. translation faults, permission faults) or some really unnecessary guest faults caused by BBM, CMOs for the first vcpu are necessary while the others later are not. By moving CMOs to the fault handlers, we can easily identify conditions where they are really needed and avoid the unnecessary ones. As it's a time consuming process to perform CMOs especially when flushing a block range, so this solution reduces much load of kvm and improve efficiency of the page table code. This patch only moves clean of D-cache to the map path, and drop the original APIs in mmu.c/mmu.h for D-cache maintenance by using what we already have in pgtable.c. Change about the I-side will come from a later patch. Signed-off-by: Yanan Wang --- arch/arm64/include/asm/kvm_mmu.h | 16 ---------------- arch/arm64/kvm/hyp/pgtable.c | 20 ++++++++++++++------ arch/arm64/kvm/mmu.c | 14 +++----------- 3 files changed, 17 insertions(+), 33 deletions(-) diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 25ed956f9af1..e9b163c5f023 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -187,22 +187,6 @@ static inline bool vcpu_has_cache_enabled(struct kvm_vcpu *vcpu) return (vcpu_read_sys_reg(vcpu, SCTLR_EL1) & 0b101) == 0b101; } -static inline void __clean_dcache_guest_page(kvm_pfn_t pfn, unsigned long size) -{ - void *va = page_address(pfn_to_page(pfn)); - - /* - * With FWB, we ensure that the guest always accesses memory using - * cacheable attributes, and we don't have to clean to PoC when - * faulting in pages. Furthermore, FWB implies IDC, so cleaning to - * PoU is not required either in this case. - */ - if (cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) - return; - - kvm_flush_dcache_to_poc(va, size); -} - static inline void __invalidate_icache_guest_page(kvm_pfn_t pfn, unsigned long size) { diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index c37c1dc4feaf..e3606c9dcec7 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -562,6 +562,12 @@ static bool stage2_pte_is_counted(kvm_pte_t pte) return !!pte; } +static bool stage2_pte_cacheable(struct kvm_pgtable *pgt, kvm_pte_t pte) +{ + u64 memattr = pte & KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR; + return memattr == KVM_S2_MEMATTR(pgt, NORMAL); +} + static void stage2_put_pte(kvm_pte_t *ptep, struct kvm_s2_mmu *mmu, u64 addr, u32 level, struct kvm_pgtable_mm_ops *mm_ops) { @@ -583,6 +589,7 @@ static int stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, { kvm_pte_t new, old = *ptep; u64 granule = kvm_granule_size(level), phys = data->phys; + struct kvm_pgtable *pgt = data->mmu->pgt; struct kvm_pgtable_mm_ops *mm_ops = data->mm_ops; if (!kvm_block_mapping_supported(addr, end, phys, level)) @@ -606,6 +613,13 @@ static int stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, stage2_put_pte(ptep, data->mmu, addr, level, mm_ops); } + /* Perform CMOs before installation of the guest stage-2 PTE */ + if (pgt->flags & KVM_PGTABLE_S2_GUEST) { + if (stage2_pte_cacheable(pgt, new) && !stage2_has_fwb(pgt)) + __flush_dcache_area(mm_ops->phys_to_virt(phys), + granule); + } + smp_store_release(ptep, new); if (stage2_pte_is_counted(new)) mm_ops->get_page(ptep); @@ -798,12 +812,6 @@ int kvm_pgtable_stage2_set_owner(struct kvm_pgtable *pgt, u64 addr, u64 size, return ret; } -static bool stage2_pte_cacheable(struct kvm_pgtable *pgt, kvm_pte_t pte) -{ - u64 memattr = pte & KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR; - return memattr == KVM_S2_MEMATTR(pgt, NORMAL); -} - static int stage2_unmap_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, enum kvm_pgtable_walk_flags flag, void * const arg) diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 2cfcfc5f4e4e..86f7dd1c234f 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -694,11 +694,6 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm, kvm_mmu_write_protect_pt_masked(kvm, slot, gfn_offset, mask); } -static void clean_dcache_guest_page(kvm_pfn_t pfn, unsigned long size) -{ - __clean_dcache_guest_page(pfn, size); -} - static void invalidate_icache_guest_page(kvm_pfn_t pfn, unsigned long size) { __invalidate_icache_guest_page(pfn, size); @@ -972,9 +967,6 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, if (writable) prot |= KVM_PGTABLE_PROT_W; - if (fault_status != FSC_PERM && !device) - clean_dcache_guest_page(pfn, vma_pagesize); - if (exec_fault) { prot |= KVM_PGTABLE_PROT_X; invalidate_icache_guest_page(pfn, vma_pagesize); @@ -1234,10 +1226,10 @@ int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) trace_kvm_set_spte_hva(hva); /* - * We've moved a page around, probably through CoW, so let's treat it - * just like a translation fault and clean the cache to the PoC. + * We've moved a page around, probably through CoW, so let's treat + * it just like a translation fault and the map handler will clean + * the cache to the PoC. */ - clean_dcache_guest_page(pfn, PAGE_SIZE); handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &pfn); return 0; } -- 2.23.0 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm