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=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 28464C63777 for ; Mon, 23 Nov 2020 18:34:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CAFB0221F7 for ; Mon, 23 Nov 2020 18:34:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="gih3TBU2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729756AbgKWSeX (ORCPT ); Mon, 23 Nov 2020 13:34:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55754 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728868AbgKWSeW (ORCPT ); Mon, 23 Nov 2020 13:34:22 -0500 Received: from mail-qk1-x736.google.com (mail-qk1-x736.google.com [IPv6:2607:f8b0:4864:20::736]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51855C0613CF for ; Mon, 23 Nov 2020 10:34:21 -0800 (PST) Received: by mail-qk1-x736.google.com with SMTP id b144so3404438qkc.13 for ; Mon, 23 Nov 2020 10:34:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=1u1sy4wI1CG6DZFHVu5ifgXp/o8YW2xyOy2wIPWsfUg=; b=gih3TBU2ie34aPD8GCBnr1hlEWJpANCJd1L/9e5q6wM6g+ySzsAsQAkZeX5ov0bm8w KMqGD2zqx81lskimJnNbWmiTfCUUH6V6jfRnz+RYqcsGIDgL+0BgOk+8BQ3zc2dgAbkX rm2QbI1sEI16WUkwm4BhRtfJkKA3OWLu9si/MKlfvUaXUekcsf3+iI++DV3ZhOfCd59z C8P60qh9BjLwDE4nOsf4L3CDrVjlYUdZ9vFSnY+7pMSSeEqky1SG/4txkpavUjNXUQZS iubB+g078hid8l+LWwEwpfH7l5JQjzSnu65jBT+60rf46aLEzD5Kf5G8050vlyTy+aBi EccA== 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=1u1sy4wI1CG6DZFHVu5ifgXp/o8YW2xyOy2wIPWsfUg=; b=uBfnr3116iVW8zfEj5oo76AGhV7Npdbi8r7wPhoki3jDbONjm/eO8zGHCSvXPHo6Ot tzW/uP05gsO4kiJOdlgdYVSe03qPoYnQAe702II09cLl5PkunqQLj0gfwHs9aBpmeiKa jV0GiSOld4uJbboAwrrfgj/uyHwj29bNUTPQQ0+mNZOM66mETDrxIEjofEAYfzpqLpIN LVTXsD3Og7tvEO2Kv+dPKX//7l/OFg6WJJqGxm102ti4UE08ICmL4WG9HSvBvQItBbBs MQjh2LWPcOdIYTHCA21vpV/IhQyiNZL/fu+GFTwV/sWUcw1pA+SFVknD/VMcjmSlQFM4 WgvQ== X-Gm-Message-State: AOAM532M1ETWgaALrmnz1py0t6i0n4ggdGxgt0r7gJ7UG38Yf+t0pSP2 +3vFlhB/AIXjgQZGkYeL3Anhnw== X-Google-Smtp-Source: ABdhPJxC7o5Vri3XQELAZq9SSztQKpp5Dk2Ag9BZU5OCfm9BfrhI8Xz3WzsV/EejngMWbFSZKb34oQ== X-Received: by 2002:a37:45c6:: with SMTP id s189mr813608qka.472.1606156460610; Mon, 23 Nov 2020 10:34:20 -0800 (PST) Received: from ziepe.ca ([206.223.160.26]) by smtp.gmail.com with ESMTPSA id x21sm4956921qtb.14.2020.11.23.10.34.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Nov 2020 10:34:19 -0800 (PST) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1khGfK-0001k7-Mn; Mon, 23 Nov 2020 14:34:18 -0400 Date: Mon, 23 Nov 2020 14:34:18 -0400 From: Jason Gunthorpe To: Pavel Tatashin Cc: Michal Hocko , linux-mm , Andrew Morton , Vlastimil Babka , LKML , David Hildenbrand , Oscar Salvador , Dan Williams , Sasha Levin , Tyler Hicks , Joonsoo Kim , Stephen Hemminger Subject: Re: Pinning ZONE_MOVABLE pages Message-ID: <20201123183418.GB5487@ziepe.ca> References: <20201123090129.GD27488@dhcp22.suse.cz> <20201123171502.GX244516@ziepe.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 23, 2020 at 12:54:16PM -0500, Pavel Tatashin wrote: > > I agree with the other emails, ZONE_MOVABLE needs to be reconciled > > with FOLL_LONGTERM - most likely by preventing ZONE_MOVABLE pages from > > being returned. This will need migration like CMA does and the point > > about faulting is only an optimization to prevent fault then immediate > > migration. > > That is right, as the first step we could just do fault and immediate > migration, which is silly, but still better than what we have now. I was looking at this CMA code lately and would love to see a cleaner/faster implementation. If you really understand how this works maybe it is an opportunity to make it all work better. Jason