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 3F663C33CA1 for ; Thu, 9 Jan 2020 17:07:19 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 191F62067D for ; Thu, 9 Jan 2020 17:07:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 191F62067D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9A9168E0006; Thu, 9 Jan 2020 12:07:18 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 90A7B8E0005; Thu, 9 Jan 2020 12:07:18 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7F91A8E0006; Thu, 9 Jan 2020 12:07:18 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0178.hostedemail.com [216.40.44.178]) by kanga.kvack.org (Postfix) with ESMTP id 653888E0005 for ; Thu, 9 Jan 2020 12:07:18 -0500 (EST) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id 03AFF8248D7C for ; Thu, 9 Jan 2020 17:07:18 +0000 (UTC) X-FDA: 76358726556.13.vest95_5cc5a6ed4b216 X-HE-Tag: vest95_5cc5a6ed4b216 X-Filterd-Recvd-Size: 1765 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf24.hostedemail.com (Postfix) with ESMTP for ; Thu, 9 Jan 2020 17:07:17 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 23063AE03; Thu, 9 Jan 2020 17:07:16 +0000 (UTC) Date: Thu, 9 Jan 2020 18:07:15 +0100 From: Michal Hocko To: Vlastimil Babka Cc: "Kirill A. Shutemov" , Matthew Wilcox , linux-mm@kvack.org, Peter Zijlstra Subject: Re: Splitting the mmap_sem Message-ID: <20200109170715.GV4951@dhcp22.suse.cz> References: <20191203222147.GV20752@bombadil.infradead.org> <20191212142457.zqp4mawjz7frpyvk@box> <20191212154002.GR32169@bombadil.infradead.org> <20200106220910.GK6788@bombadil.infradead.org> <20200107123415.gqklwca4qilva2yr@box> <20200107135459.GL6788@bombadil.infradead.org> <20200107142714.gjkdcikbbwfbvl2r@box> <20200109170318.GU4951@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200109170318.GU4951@dhcp22.suse.cz> User-Agent: Mutt/1.12.2 (2019-09-21) 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 Thu 09-01-20 18:03:25, Michal Hocko wrote: > I might misremember but RCU based VMA handling has > been considered in the past. I do not remember details but there were > some problems and page tables allocation is not the biggest one. I have found https://pdos.csail.mit.edu/papers/rcuvm:asplos12.pdf in my notes. I managed to forget everything but maybe it will be useful for a reference. -- Michal Hocko SUSE Labs