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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 71048C43331 for ; Thu, 26 Mar 2020 07:16:03 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3BAE020714 for ; Thu, 26 Mar 2020 07:16:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3BAE020714 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C2CEB6B000D; Thu, 26 Mar 2020 03:16:02 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BDE0D6B000E; Thu, 26 Mar 2020 03:16:02 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ACBC76B0010; Thu, 26 Mar 2020 03:16:02 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0227.hostedemail.com [216.40.44.227]) by kanga.kvack.org (Postfix) with ESMTP id 931676B000D for ; Thu, 26 Mar 2020 03:16:02 -0400 (EDT) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id A0C605DC2 for ; Thu, 26 Mar 2020 07:16:02 +0000 (UTC) X-FDA: 76636654164.11.pest43_8bfa1ae00a70d X-HE-Tag: pest43_8bfa1ae00a70d X-Filterd-Recvd-Size: 3207 Received: from huawei.com (szxga07-in.huawei.com [45.249.212.35]) by imf02.hostedemail.com (Postfix) with ESMTP for ; Thu, 26 Mar 2020 07:16:01 +0000 (UTC) Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id C2F379D56FD4517F2B7F; Thu, 26 Mar 2020 15:15:38 +0800 (CST) Received: from [127.0.0.1] (10.173.220.25) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.487.0; Thu, 26 Mar 2020 15:15:29 +0800 Subject: Re: [RFC PATCH v4 0/6] arm64: tlb: add support for TTL feature To: Peter Zijlstra CC: , , , , , , , , , , , , , , , , , , , , , , , References: <20200324134534.1570-1-yezhenyu2@huawei.com> <20200324150155.GH20713@hirez.programming.kicks-ass.net> <20200325133201.GI20713@hirez.programming.kicks-ass.net> From: Zhenyu Ye Message-ID: <43164360-8204-89c6-0d4d-c38b1aa09642@huawei.com> Date: Thu, 26 Mar 2020 15:15:27 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.3.0 MIME-Version: 1.0 In-Reply-To: <20200325133201.GI20713@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset="gbk" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.173.220.25] X-CFilter-Loop: Reflected X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 2020/3/25 21:32, Peter Zijlstra wrote: > On Wed, Mar 25, 2020 at 12:49:45PM +0800, Zhenyu Ye wrote: >> Hi Peter, >> >> On 2020/3/24 23:01, Peter Zijlstra wrote: >>> On Tue, Mar 24, 2020 at 09:45:28PM +0800, Zhenyu Ye wrote: >>>> In order to reduce the cost of TLB invalidation, the ARMv8.4 TTL >>>> feature allows TLBs to be issued with a level allowing for quicker >>>> invalidation. This series provide support for this feature. >>>> >>>> Patch 1 and Patch 2 was provided by Marc on his NV series[1] patches, >>>> which detect the TTL feature and add __tlbi_level interface. >>> >>> I realy hate how it makes vma->vm_flags more important for tlbi. >>> >> >> Thanks for your review. >> >> The tlbi interfaces only have two parameters: vma and addr. If we >> try to not use vma->vm_flags, we may should have to add a parameter >> to some of these interfaces(such as flush_tlb_range), which are >> common to all architectures. >> >> I'm not sure if this is feasible, because this feature is only >> supported by ARM64 currently. > > Power (p9-radix) also has level dependent invalidation instructions, so > at the very least you can hook them up as well. > > . > Thanks, I will push my next version soon. Zhenyu .