Received: by 2002:a05:6a10:8c0a:0:0:0:0 with SMTP id go10csp3993511pxb; Tue, 26 Jan 2021 09:36:20 -0800 (PST) X-Google-Smtp-Source: ABdhPJxywUHuq2Eo9IwopJqEjQsVIn3VC8WT2GoCg4e5TOPIsDMW1HaK1TqMpy/i994SzGBNnmt/ X-Received: by 2002:aa7:cdcb:: with SMTP id h11mr5490888edw.237.1611682579890; Tue, 26 Jan 2021 09:36:19 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1611682579; cv=none; d=google.com; s=arc-20160816; b=e8Hxr4fj9Tl7X4gSMldYbnHagLukwMga+s5933DfKWtgmROaluTMGUg5zCuT957dGY doYgumrqf55f0TNpY9Jk5c7noy/i58KC0KZdGXnVvwUipSIXogt7AjgmwuW9d49E0uri mwH9JM2QRjyEmjsARiJuZnSvJXVf3jrCbKEUWkm+4mlUx7xCwUUXQNaUGynsQqBPc6zM ZUNE9bvasmveY0DjRKLocm4tSKJG15eGGhaUh7U+820g+8j8CzOUVxw1U3pvVjWNAvyn hhSxzFYJHmAbaEj0r3eq8kOYH8nBinwv8abiaky6FcQb7MX1W2HkNys9o7kh1YNjcQyK KI0Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:references:in-reply-to:message-id :date:subject:cc:to:from; bh=zCbKFqxCgCkAZF8H1P3drxiOXMtsYuJYZIvZoDToHB4=; b=B5UnMp7lO8sHf60brfaA3qirqQZRyTE6aajIRgEZ0De5mbQId7+xq2B1W+QpYA4Z57 Gz48odw+na3cVInCLl8mYbys/ZS8HQXJvmtQYM7ywgAxtHaeyX1+S2N1bxAisz55Y7OP 0N3Ot+IYGr+V/Pev9LXR+xuOIF+a/n/TX6AeQ3luTsd3Ww9bqPts5P/YaOIiYN5uI1HE LN1FCyJ1WziTi6blwn85PI9C8uSEQaOjChOFdbKzclM7CBf7wDdx4P6EFbuSXlXiMTKa a5vybvbjHuT0wxxgXwZurO/WBYL9+mBpbkJX9GFzpn1PviMmUAbxFB3+ehvXvngNSrST Agew== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id b15si8976483edz.486.2021.01.26.09.35.51; Tue, 26 Jan 2021 09:36:19 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726365AbhAZGd2 (ORCPT + 99 others); Tue, 26 Jan 2021 01:33:28 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:11874 "EHLO szxga07-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729303AbhAYOMK (ORCPT ); Mon, 25 Jan 2021 09:12:10 -0500 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4DPWvr41hmz7Zrf; Mon, 25 Jan 2021 22:09:44 +0800 (CST) Received: from DESKTOP-TMVL5KK.china.huawei.com (10.174.187.128) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.498.0; Mon, 25 Jan 2021 22:10:48 +0800 From: Yanan Wang To: Marc Zyngier , Will Deacon , "Catalin Marinas" , James Morse , "Julien Thierry" , Suzuki K Poulose , , , , CC: , , Yanan Wang Subject: [PATCH 2/2] KVM: arm64: Skip the cache flush when coalescing tables into a block Date: Mon, 25 Jan 2021 22:10:44 +0800 Message-ID: <20210125141044.380156-3-wangyanan55@huawei.com> X-Mailer: git-send-email 2.8.4.windows.1 In-Reply-To: <20210125141044.380156-1-wangyanan55@huawei.com> References: <20210125141044.380156-1-wangyanan55@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.174.187.128] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After dirty-logging is stopped for a VM configured with huge mappings, KVM will recover the table mappings back to block mappings. As we only replace the existing page tables with a block entry and the cacheability has not been changed, the cache maintenance opreations can be skipped. Signed-off-by: Yanan Wang --- arch/arm64/kvm/mmu.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 8e8549ea1d70..37b427dcbc4f 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -744,7 +744,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, { int ret = 0; bool write_fault, writable, force_pte = false; - bool exec_fault; + bool exec_fault, adjust_hugepage; bool device = false; unsigned long mmu_seq; struct kvm *kvm = vcpu->kvm; @@ -872,12 +872,18 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, mark_page_dirty(kvm, gfn); } - if (fault_status != FSC_PERM && !device) + /* + * There is no necessity to perform cache maintenance operations if we + * will only replace the existing table mappings with a block mapping. + */ + adjust_hugepage = fault_granule < vma_pagesize ? true : false; + if (fault_status != FSC_PERM && !device && !adjust_hugepage) clean_dcache_guest_page(pfn, vma_pagesize); if (exec_fault) { prot |= KVM_PGTABLE_PROT_X; - invalidate_icache_guest_page(pfn, vma_pagesize); + if (!adjust_hugepage) + invalidate_icache_guest_page(pfn, vma_pagesize); } if (device) -- 2.19.1