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 1D3C3C32771 for ; Wed, 21 Sep 2022 06:54:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229578AbiIUGx7 (ORCPT ); Wed, 21 Sep 2022 02:53:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230107AbiIUGx4 (ORCPT ); Wed, 21 Sep 2022 02:53:56 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 4E8653340C; Tue, 20 Sep 2022 23:53:54 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 16D8C143D; Tue, 20 Sep 2022 23:54:00 -0700 (PDT) Received: from [10.162.41.8] (unknown [10.162.41.8]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0949D3F73D; Tue, 20 Sep 2022 23:54:11 -0700 (PDT) Message-ID: <888da5f3-104c-3929-c21e-c710922d6f1e@arm.com> Date: Wed, 21 Sep 2022 12:23:40 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH v3 4/4] arm64: support batched/deferred tlb shootdown during page reclamation Content-Language: en-US To: Yicong Yang , akpm@linux-foundation.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org, catalin.marinas@arm.com, will@kernel.org, linux-doc@vger.kernel.org Cc: corbet@lwn.net, peterz@infradead.org, arnd@arndb.de, linux-kernel@vger.kernel.org, darren@os.amperecomputing.com, yangyicong@hisilicon.com, huzhanyuan@oppo.com, lipeifeng@oppo.com, zhangshiming@oppo.com, guojian@oppo.com, realmz6@gmail.com, linux-mips@vger.kernel.org, openrisc@lists.librecores.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, Barry Song <21cnbao@gmail.com>, wangkefeng.wang@huawei.com, xhao@linux.alibaba.com, prime.zeng@hisilicon.com, Barry Song , Nadav Amit , Mel Gorman References: <20220822082120.8347-1-yangyicong@huawei.com> <20220822082120.8347-5-yangyicong@huawei.com> From: Anshuman Khandual In-Reply-To: <20220822082120.8347-5-yangyicong@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On 8/22/22 13:51, Yicong Yang wrote: > +static inline void arch_tlbbatch_add_mm(struct arch_tlbflush_unmap_batch *batch, > + struct mm_struct *mm, > + unsigned long uaddr) > +{ > + __flush_tlb_page_nosync(mm, uaddr); > +} > + > +static inline void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch) > +{ > + dsb(ish); > +} Just wondering if arch_tlbbatch_add_mm() could also detect continuous mapping TLB invalidation requests on a given mm and try to generate a range based TLB invalidation such as flush_tlb_range(). struct arch_tlbflush_unmap_batch via task->tlb_ubc->arch can track continuous ranges while being queued up via arch_tlbbatch_add_mm(), any range formed can later be flushed in subsequent arch_tlbbatch_flush() ? OR It might not be worth the effort and complexity, in comparison to performance improvement, TLB range flush brings in ?