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=-1.0 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 4DB88C54FC9 for ; Tue, 21 Apr 2020 13:00:45 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 18E322076B for ; Tue, 21 Apr 2020 13:00:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 18E322076B 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 8E4308E0005; Tue, 21 Apr 2020 09:00:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8942C8E0003; Tue, 21 Apr 2020 09:00:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7A9CA8E0005; Tue, 21 Apr 2020 09:00:44 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0207.hostedemail.com [216.40.44.207]) by kanga.kvack.org (Postfix) with ESMTP id 5DD268E0003 for ; Tue, 21 Apr 2020 09:00:44 -0400 (EDT) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 103C1583B for ; Tue, 21 Apr 2020 13:00:44 +0000 (UTC) X-FDA: 76731871608.05.point53_65b6ff20d05f X-HE-Tag: point53_65b6ff20d05f X-Filterd-Recvd-Size: 3314 Received: from mail-wr1-f65.google.com (mail-wr1-f65.google.com [209.85.221.65]) by imf36.hostedemail.com (Postfix) with ESMTP for ; Tue, 21 Apr 2020 13:00:43 +0000 (UTC) Received: by mail-wr1-f65.google.com with SMTP id t14so16318185wrw.12 for ; Tue, 21 Apr 2020 06:00:43 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=d1uMvUXQjbS/0KLMRZ86LK6hNkLdmRR8fYk2ZNXjSys=; b=LC0319njiTo3GAFgqOz54bkkW5W9gpenpQagaIu70FRKPPzUOMyvpXl0sfnFLqhlmr oFTlvvIpwMzMkm+uTWPUqc8tLxwE+UpN60/RfhuILl76eluII9N946Tv6OptyYtWdiY5 8S9tJAx3kyVd+09T/aXjS/JSjYBSlnD+IdvKtP4vOzGov3WE2wNESU15mojGQjOwTYY/ O1QVLfA9lmlV9gadvIrsTPWJQDVopoEl2QBaI7OeN40PkoMP2QX9stB4U7gvlsuk9vMO mMSarq/XEOfRPyw9rOpfElqrslSvcq8Zgw3YJ2iYKGTrilrk7rdUBher8VKuLRHjhg/d YyoQ== X-Gm-Message-State: AGi0PuZ+NVpupaloHfvXFmdo7pJXp0SWZ+bzKQli1sv9K/Z98RcuyDk2 XIHydqpBtVz1f3ASZ46zB+s= X-Google-Smtp-Source: APiQypKJR78ctjPBsqtt/DZKn+XfUmCeWp767MoDRdbMumP1OqhK8HCppsZGycXD6/M3j+ZeqCj8sA== X-Received: by 2002:a5d:498b:: with SMTP id r11mr23868580wrq.368.1587474042504; Tue, 21 Apr 2020 06:00:42 -0700 (PDT) Received: from localhost (ip-37-188-130-62.eurotel.cz. [37.188.130.62]) by smtp.gmail.com with ESMTPSA id h17sm3329946wmm.6.2020.04.21.06.00.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Apr 2020 06:00:41 -0700 (PDT) Date: Tue, 21 Apr 2020 15:00:40 +0200 From: Michal Hocko To: Vlastimil Babka Cc: Will Deacon , Prathu Baronia , catalin.marinas@arm.com, alexander.duyck@gmail.com, chintan.pandya@oneplus.com, akpm@linux-foundation.org, linux-mm@kvack.org, gregkh@linuxfoundation.com, gthelen@google.com, jack@suse.cz, ken.lin@oneplus.com, gasine.xu@oneplus.com, ying.huang@intel.com, mark.rutland@arm.com Subject: Re: [PATCH v2] mm: Optimized hugepage zeroing & copying from user Message-ID: <20200421130040.GH27314@dhcp22.suse.cz> References: <20200414153829.GA15230@oneplus.com> <87r1wpzavo.fsf@yhuang-dev.intel.com> <20200419155856.dtwxomdkyujljdfi@oneplus.com> <87k12bt3ff.fsf@yhuang-dev.intel.com> <20200421093621.3fuptvf2qbyfzwfz@oneplus.com> <20200421100932.GC17256@willie-the-truck> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 Tue 21-04-20 14:47:13, Vlastimil Babka wrote: [...] > In that case the generic implementation should be just reverted to be simple and > not assume any (micro)architectural details. If any architecture wants an > optimized version they could add it opt-in, and justifify it by using real > workloads, not microbenchmarks. Exactly! And I have requested that already with no response. So can we simply go and make the current implementation x86 specific and reintroduce the previous one as a default? -- Michal Hocko SUSE Labs