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=DKIM_SIGNED,DKIM_VALID, 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 E642CCA9EC2 for ; Mon, 28 Oct 2019 12:26:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC77E20873 for ; Mon, 28 Oct 2019 12:26:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=shutemov-name.20150623.gappssmtp.com header.i=@shutemov-name.20150623.gappssmtp.com header.b="atWtbQR8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388758AbfJ1M0K (ORCPT ); Mon, 28 Oct 2019 08:26:10 -0400 Received: from mail-lj1-f194.google.com ([209.85.208.194]:37211 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726302AbfJ1M0K (ORCPT ); Mon, 28 Oct 2019 08:26:10 -0400 Received: by mail-lj1-f194.google.com with SMTP id l21so11113091lje.4 for ; Mon, 28 Oct 2019 05:26:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=z5AyluMv2qTfIyVRClKMssZVhcw31wtXHvj4WXII8HU=; b=atWtbQR8Vni3TfC0Ou+ohngYF0wSzz2oI54BLC4Rn0pqqrVdXXHERQ7J2p9qypr+XZ w671rRO+1w3oacaPradqsKCJKlFCWwcrTivnMSaNfwPfhoseesQb5wtHpqc4FP0FISd0 664FGjtxUlOHAWuIOuwnJArSlmxtXFthdxka+5/ccWlD1JBBYOkECofJn0IMld3RyFlY 1yGBplLXLudj5uorCML+YK9r7r19qeJyUdMsdgF4z/xbfdl9feVaeMHMZEnSQhV7mNPM 613OuKvidHEzy0CXc7uILZPNmIWYvzmvaKvQDZ1wGiu4KMzl6+CIKWGBgoa2S9twYun7 cTXQ== 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:user-agent; bh=z5AyluMv2qTfIyVRClKMssZVhcw31wtXHvj4WXII8HU=; b=CME1PV9q4ggWC29VnXg+IK7qboEzJSa7rS/0Lhp+RMBT2eb5AJcfx/xPa4K1tBXD7t NIzcURokt1ZtV5QdWdzTsMFQ4SQcJ1RosK+48hHsnXXeh+9HciJ2vFXMpsFCRPvjNuST sgPCvU1NjKJKChnyrvbKKfwxsIP5L+0g3i/XtaVQ2Exu2KwPEJy7xf5jkDgEDRQuKH9j jLAomDMGNrcQ7bxJkLVUcXVaGRH0mQ6xnwp5IXBzRffSgGDrid9bDEGJfu5Cu55S1kdC O2i6aviNlfcAUk12fZeO2rDlz1ql7Dq4V7hxsCeWVp2ymn16+wylHY0nyPchvm0L/tcB HwUQ== X-Gm-Message-State: APjAAAWjGuHYqugLYoWloUXV3wwWViXFkMtfQXz0J5SS71RU9WGusNnl K23TLPpAMZe3OTPEJGMoG4j3/A== X-Google-Smtp-Source: APXvYqzX/kNTOsUwdnrZG6QsXdZ+qGMpKvs2rtBhXMpIja+rf/TeDoG0fNE0SxHQ7hNz799BexRZpw== X-Received: by 2002:a2e:2bc7:: with SMTP id r68mr12017511ljr.27.1572265568148; Mon, 28 Oct 2019 05:26:08 -0700 (PDT) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id 87sm4571309ljs.23.2019.10.28.05.26.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Oct 2019 05:26:07 -0700 (PDT) Received: by box.localdomain (Postfix, from userid 1000) id 30BA4100242; Mon, 28 Oct 2019 15:26:09 +0300 (+03) Date: Mon, 28 Oct 2019 15:26:09 +0300 From: "Kirill A. Shutemov" To: Hillf Danton Cc: linux-mm , Andrew Morton , linux-kernel , Matthew Wilcox , Michal Hocko , Johannes Weiner , Shakeel Butt , Minchan Kim , Mel Gorman , Vladimir Davydov , Jan Kara Subject: Re: [RFC v2] mm: add page preemption Message-ID: <20191028122609.k5suvp7b57oxglvj@box> References: <20191026112808.14268-1-hdanton@sina.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191026112808.14268-1-hdanton@sina.com> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Oct 26, 2019 at 07:28:08PM +0800, Hillf Danton wrote: > @@ -218,6 +219,9 @@ struct page { > > #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS > int _last_cpupid; > +#else > + int prio; > +#define CONFIG_PAGE_PREEMPTION PP > #endif > } _struct_page_alignment; > No. There's a really good reason we trying hard to push the _last_cpuid into page flags instead of growing the struct page by 4 bytes. I don't think your feature worth 0.1% of RAM and a lot of cache misses that this change would generate. -- Kirill A. Shutemov