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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E1A8C32771 for ; Wed, 21 Sep 2022 06:53:56 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B109F940007; Wed, 21 Sep 2022 02:53:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AC0136B0073; Wed, 21 Sep 2022 02:53:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9D606940007; Wed, 21 Sep 2022 02:53:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 91B2C6B0072 for ; Wed, 21 Sep 2022 02:53:55 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 629EFAADC8 for ; Wed, 21 Sep 2022 06:53:55 +0000 (UTC) X-FDA: 79935177630.05.B51A43B Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf22.hostedemail.com (Postfix) with ESMTP id 80AA1C0019 for ; Wed, 21 Sep 2022 06:53:54 +0000 (UTC) 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; 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spf=pass (imf22.hostedemail.com: domain of anshuman.khandual@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=anshuman.khandual@arm.com X-Stat-Signature: 9n7ddaabhfzah5ry8t1tphju8iekg6ex X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 80AA1C0019 Authentication-Results: imf22.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf22.hostedemail.com: domain of anshuman.khandual@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=anshuman.khandual@arm.com X-Rspam-User: X-HE-Tag: 1663743234-42347 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 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 ?