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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 2EAB8C433ED for ; Sat, 17 Apr 2021 01:05:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9BE0610CB for ; Sat, 17 Apr 2021 01:05:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234136AbhDQBFo (ORCPT ); Fri, 16 Apr 2021 21:05:44 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:16132 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229719AbhDQBFk (ORCPT ); Fri, 16 Apr 2021 21:05:40 -0400 Received: from DGGEMS407-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4FMZYP6ZQxzpZ7j; Sat, 17 Apr 2021 09:02:17 +0800 (CST) Received: from [10.174.187.224] (10.174.187.224) by DGGEMS407-HUB.china.huawei.com (10.3.19.207) with Microsoft SMTP Server id 14.3.498.0; Sat, 17 Apr 2021 09:05:05 +0800 Subject: Re: [PATCH v4 2/2] kvm/arm64: Try stage2 block mapping for host device MMIO To: Marc Zyngier References: <20210415140328.24200-1-zhukeqian1@huawei.com> <20210415140328.24200-3-zhukeqian1@huawei.com> <8f55b64f-b4dd-700e-c997-8de9c5ea282f@huawei.com> <87a6py2ss9.wl-maz@kernel.org> CC: , , , , From: Keqian Zhu Message-ID: Date: Sat, 17 Apr 2021 09:05:05 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <87a6py2ss9.wl-maz@kernel.org> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.187.224] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi Marc, On 2021/4/16 22:44, Marc Zyngier wrote: > On Thu, 15 Apr 2021 15:08:09 +0100, > Keqian Zhu wrote: >> >> Hi Marc, >> >> On 2021/4/15 22:03, Keqian Zhu wrote: >>> The MMIO region of a device maybe huge (GB level), try to use >>> block mapping in stage2 to speedup both map and unmap. >>> >>> Compared to normal memory mapping, we should consider two more >>> points when try block mapping for MMIO region: >>> >>> 1. For normal memory mapping, the PA(host physical address) and >>> HVA have same alignment within PUD_SIZE or PMD_SIZE when we use >>> the HVA to request hugepage, so we don't need to consider PA >>> alignment when verifing block mapping. But for device memory >>> mapping, the PA and HVA may have different alignment. >>> >>> 2. For normal memory mapping, we are sure hugepage size properly >>> fit into vma, so we don't check whether the mapping size exceeds >>> the boundary of vma. But for device memory mapping, we should pay >>> attention to this. >>> >>> This adds get_vma_page_shift() to get page shift for both normal >>> memory and device MMIO region, and check these two points when >>> selecting block mapping size for MMIO region. >>> >>> Signed-off-by: Keqian Zhu >>> --- >>> arch/arm64/kvm/mmu.c | 61 ++++++++++++++++++++++++++++++++++++-------- >>> 1 file changed, 51 insertions(+), 10 deletions(-) >>> >>> diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c >>> index c59af5ca01b0..5a1cc7751e6d 100644 >>> --- a/arch/arm64/kvm/mmu.c >>> +++ b/arch/arm64/kvm/mmu.c >>> @@ -738,6 +738,35 @@ transparent_hugepage_adjust(struct kvm_memory_slot *memslot, >>> return PAGE_SIZE; >>> } >>> [...] >>> + /* >>> + * logging_active is guaranteed to never be true for VM_PFNMAP >>> + * memslots. >>> + */ >>> + if (logging_active) { >>> force_pte = true; >>> vma_shift = PAGE_SHIFT; >>> + } else { >>> + vma_shift = get_vma_page_shift(vma, hva); >>> } >> I use a if/else manner in v4, please check that. Thanks very much! > > That's fine. However, it is getting a bit late for 5.13, and we don't > have much time to left it simmer in -next. I'll probably wait until > after the merge window to pick it up. OK, no problem. Thanks! :) BRs, Keqian