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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 06D22C2BA2B for ; Thu, 16 Apr 2020 20:37:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D1382206A2 for ; Thu, 16 Apr 2020 20:37:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587069462; bh=u5aVN4WZK+kEholtZnnhIh7+K2tLHxSM9C2zW9iB8eo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=w/fjBc8dgkrTMQqxMOMx23C7eoTWE9CZrpxptYY4qwVYfLhDVWSCGtuRfQCrqMo70 vm8Dqo27MeMSLkTiqVSXNdoVRVSYoLv1xvSIXBWlovx8NC7jEQoKx4U/RBt+DEeVEE zeJHJgWVDlXYu4Xzt81EE0scZRX4TJYWTiChbQWc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730593AbgDPUhm (ORCPT ); Thu, 16 Apr 2020 16:37:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726114AbgDPUhl (ORCPT ); Thu, 16 Apr 2020 16:37:41 -0400 Received: from mail-pf1-x442.google.com (mail-pf1-x442.google.com [IPv6:2607:f8b0:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 78E0DC061A0C; Thu, 16 Apr 2020 13:37:41 -0700 (PDT) Received: by mail-pf1-x442.google.com with SMTP id w65so2186142pfc.12; 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=MxW0PSGrt0SfuwDyrVTKA3/ccX+uoQSfUwzzRijA+xbrXZ8N3RR3XATDn3qwVTRRDL iGCVR32pLV8H7j0LFp1Ni7HdIGpXH+H/a6Uqp2jgP1Dnpqyzii0KvvFOSU+aQXyXqkXj iqeZGbSSs0NOyTyMZum/tpG5eyng8DJCb2B31lEyTDbeDgqMs5VJKwXCrBOReaclTLq/ 15bQb8DPi27+330AWKImJ0vyuplQT4mnL0i2r8BOwHDwWz706yYzJpiKu0BlaCy6BjS1 OY9Aapp+wyBRXbc8SyIQtg/lRcLipRQ51tiVcnzjp1zY0JxfvqyBQq4noNlB1NQQrtd5 oqyQ== X-Gm-Message-State: AGi0PuYZnxIMTeu51BcxARMuli6w1G9tnZ/nM0H3b1cchJLd6EZ5IBF4 om3sGt3jb63zUcpvsdtrREY= 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> Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org 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.