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=-5.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 B1B1CC38A29 for ; Thu, 16 Apr 2020 20:37:43 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6E78722202 for ; Thu, 16 Apr 2020 20:37:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="gnCYkWmG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6E78722202 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 01CA68E00E1; Thu, 16 Apr 2020 16:37:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F10828E00BC; Thu, 16 Apr 2020 16:37:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E25288E00E1; Thu, 16 Apr 2020 16:37:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0198.hostedemail.com [216.40.44.198]) by kanga.kvack.org (Postfix) with ESMTP id C606D8E00BC for ; Thu, 16 Apr 2020 16:37:42 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 88C644DDB for ; Thu, 16 Apr 2020 20:37:42 +0000 (UTC) X-FDA: 76714879164.18.event40_433df961c9010 X-HE-Tag: event40_433df961c9010 X-Filterd-Recvd-Size: 5616 Received: from mail-pg1-f193.google.com (mail-pg1-f193.google.com [209.85.215.193]) by imf12.hostedemail.com (Postfix) with ESMTP for ; Thu, 16 Apr 2020 20:37:41 +0000 (UTC) Received: by mail-pg1-f193.google.com with SMTP id p8so2196800pgi.5 for ; Thu, 16 Apr 2020 13:37:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=XptGLsb8LK835cBV0jSCf0HRG/zsBSED6dv7tPgulp4=; b=gnCYkWmGETLB8PFSLV04Wdrz2FK+gEIIVYi1koqv0Kj68T1sE9a0zKATXAPY7gyzfJ suAROh/dNMoI6pHy/mCCmAEukmmvuLcuT+oRiOR7pSsJ7zs8in52Gebp1M1SYorAU4tK gOw3D6aDwjxZUg6c2JW6Y26Oj3CTSIyaIex5HlRUwrN0Akr9mc2rJN/ETJ63AkMWNaPZ lBqmfTlQr2tQLv3hxk3korpwrPMIzUOkCHKM9MiAc5EcYNrnyoXofMkm1N6eYHhs/DeF 913mMDnNGshbbDlgR/ygTf2Uto9ROB2t1oEKoFobtuWYnROIBcT0nnQEOaLeZGRWafc8 pefQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=XptGLsb8LK835cBV0jSCf0HRG/zsBSED6dv7tPgulp4=; b=GhAIbg248INLnbOovheeobhx0FC+WpMXw1LkQxR/QwRgzz7z5UGj+roAkx9reSCDzD 9Dxlq2fGzxu4A3JITxAOjU3Cs7u3t21gL1rfmuAafTiqYo5uUApi8/ZaqmEeVEEpaGOA PnJ6rM/vyJMFcdcewv2jON7BPkiUWSxzAPyJzc+hOrGhKaO4mDQofKx7iXNnn/P3EPL9 lBDjArGYLQg2k9NIr4IIiiHD+5hoQL0RK0wLpJBCqmsz7Oh90jEGDis7kILyKNhGN3v3 Y8uIfEgEpbopbiT7JPxserGzHksvJYclqviB6ltfrgmrTdzx1j6a0nmrZokqFOIPDt1x 0PBg== X-Gm-Message-State: AGi0PuY+9AZ5A+8FXvuOpSQxgKu+1HcwdfAlC9ZJ6QGWVlaVw0KkB1YD ceQv8nOo5AxN0WJFbaCo+XY= X-Google-Smtp-Source: APiQypLz/G622vMAZI/1t7tx6iXdrAiprqdhsptFvPk2bcCnaQJR//IYq0Xxli2CBTatOLYd6eCB1g== X-Received: by 2002:a63:2e03:: with SMTP id u3mr15186804pgu.121.1587069460712; Thu, 16 Apr 2020 13:37:40 -0700 (PDT) Received: from google.com ([2601:647:4001:3000::50e3]) by smtp.gmail.com with ESMTPSA id u13sm3654978pjb.45.2020.04.16.13.37.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Apr 2020 13:37:38 -0700 (PDT) Date: Thu, 16 Apr 2020 13:37:36 -0700 From: Minchan Kim To: Christoph Hellwig Cc: Sergey Senozhatsky , Peter Zijlstra , Andrew Morton , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , x86@kernel.org, David Airlie , Daniel Vetter , Laura Abbott , Sumit Semwal , Sakari Ailus , Nitin Gupta , Robin Murphy , Christophe Leroy , linuxppc-dev@lists.ozlabs.org, linux-hyperv@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 10/28] mm: only allow page table mappings for built-in zsmalloc Message-ID: <20200416203736.GB50092@google.com> References: <20200408115926.1467567-1-hch@lst.de> <20200408115926.1467567-11-hch@lst.de> <20200409160826.GC247701@google.com> <20200409165030.GG20713@hirez.programming.kicks-ass.net> <20200409170813.GD247701@google.com> <20200410023845.GA2354@jagdpanzerIV.localdomain> <20200410231136.GA101325@google.com> <20200411072052.GA31242@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200411072052.GA31242@lst.de> 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: Hi Christoph, Sorry for the late. On Sat, Apr 11, 2020 at 09:20:52AM +0200, Christoph Hellwig wrote: > Hi Minchan, > > On Fri, Apr 10, 2020 at 04:11:36PM -0700, Minchan Kim wrote: > > It doesn't mean we couldn't use zsmalloc as module any longer. It means > > we couldn't use zsmalloc as module with pgtable mapping whcih was little > > bit faster on microbenchmark in some architecutre(However, I usually temped > > to remove it since it had several problems). However, we could still use > > zsmalloc as module as copy way instead of pgtable mapping. Thus, if someone > > really want to rollback the feature, they should provide reasonable reason > > why it doesn't work for them. "A little fast" wouldn't be enough to exports > > deep internal to the module. > > do you have any data how much faster it is on arm (and does that include > arm64 as well)? Besides the exports which were my prime concern, https://github.com/sjenning/zsmapbench I need to recall the memory. IIRC, it was almost 30% faster at that time in ARM so was not trivial at that time. However, it was story from several years ago. > zsmalloc with pgtable mappings also is the only user of map_kernel_range > outside of vmalloc.c, if it really is another code base for tiny > improvements we could mark map_kernel_range or in fact remove it entirely > and open code it in the remaining callers. I alsh have temped to remove it. Let me have time to revist it in this chance. Thanks.