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=-4.1 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 DF318C433E7 for ; Wed, 2 Sep 2020 18:48:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C392E2072A for ; Wed, 2 Sep 2020 18:48:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="iOo7RQZt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727984AbgIBSs5 (ORCPT ); Wed, 2 Sep 2020 14:48:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52542 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726426AbgIBSsy (ORCPT ); Wed, 2 Sep 2020 14:48:54 -0400 Received: from mail-qt1-x843.google.com (mail-qt1-x843.google.com [IPv6:2607:f8b0:4864:20::843]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 74EB9C061244 for ; Wed, 2 Sep 2020 11:48:54 -0700 (PDT) Received: by mail-qt1-x843.google.com with SMTP id 92so4398523qtb.6 for ; Wed, 02 Sep 2020 11:48:54 -0700 (PDT) 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=IAZmJcGSADpKomYs9EJjVcf5Ol1FIgBcbrtPEk8iKqE=; b=iOo7RQZtWH3T1aKczc1Zfz7wtbIXrsunDFSqQubu1MAkmqhyWqmjcKxVyr5EkTsbrD +BKMT8QlzGw936IJeCNp5kjoiS27cxdja8YVg25EfSQFGsDYhcpk+MfkwOyb+PRoecu+ tKCFGVVejOZPgYbxp39vwVyBNruH1p9j/QpOFG/m64EfwgOQ/tPMtIST82gWgzjMFA9M lAH0PPWIenpoL5MXHJYjlEv1CkiUPoYrrK+yvJ1E5VhecoAi+2pcmbKgTw4/LV3ulecS 2pPWAvD8l4WvqFeg80uCvXF1yJNAYaO4aZMSe8jaEuYpAmM2XPY8qO05e8IlUpbCTPZq oq7g== 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=IAZmJcGSADpKomYs9EJjVcf5Ol1FIgBcbrtPEk8iKqE=; b=WiArrjB7kr+QeKtksupR6+vxvC7MKbfGLncIJry2U6/2bYXHcemhBG2BzqtDMjW7Tf wVyfRbZ8WB4UDlSkCcG5ohQS2KBtmvK8Z1VP09LPpIHCouvw8Tr7t/zyhcvw+rpqIQAS sEHIj1l79nc3YmeoQUvB88chjORk98EwCcZhc7KzXMMeb0eBkG7vqX2+wNgOvw10e/nR OZAa0cebG9ff7mHl1u9qWECT6GeF0U25O4ep5cWrfz4/1H/kbtl/bL+R4a9QHoZ8G+f6 537H+v9FAw+FAQnyanSQd5LX4kfpzhrQAbrs8Mi69hTr4dZoFtWo4xteI4iKLv4fcyhg adUg== X-Gm-Message-State: AOAM530HaG5+FFwq34ooalErwdeG7EQY+Yf/ufVCFR3Uy2ed+KQlVQo3 p1vz31HKY7JNuRyBWuNI96qWVA== X-Google-Smtp-Source: ABdhPJz9TDGFI/zT81Y7z8xsM0mVbiopCrzAgSNgeJfHXFsCnHnolPGXBDlckYXMZ6bO0v1QyQ0VsQ== X-Received: by 2002:ac8:411c:: with SMTP id q28mr8038280qtl.254.1599072533619; Wed, 02 Sep 2020 11:48:53 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-156-34-48-30.dhcp-dynamic.fibreop.ns.bellaliant.net. [156.34.48.30]) by smtp.gmail.com with ESMTPSA id d47sm196272qta.63.2020.09.02.11.48.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Sep 2020 11:48:53 -0700 (PDT) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1kDXoS-005xTU-BT; Wed, 02 Sep 2020 15:48:52 -0300 Date: Wed, 2 Sep 2020 15:48:52 -0300 From: Jason Gunthorpe To: Zi Yan Cc: linux-mm@kvack.org, Roman Gushchin , Rik van Riel , "Kirill A . Shutemov" , Matthew Wilcox , Shakeel Butt , Yang Shi , David Nellans , linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 00/16] 1GB THP support on x86_64 Message-ID: <20200902184852.GH24045@ziepe.ca> References: <20200902180628.4052244-1-zi.yan@sent.com> <20200902184053.GF24045@ziepe.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 02, 2020 at 02:45:37PM -0400, Zi Yan wrote: > > Surprised this doesn't touch mm/pagewalk.c ? > > 1GB PUD page support is present for DAX purpose, so the code is there > in mm/pagewalk.c already. I only needed to supply ops->pud_entry when using > the functions in mm/pagewalk.c. :) Yes, but doesn't this change what is possible under the mmap_sem without the page table locks? ie I would expect some thing like pmd_trans_unstable() to be required as well for lockless walkers. (and I don't think the pmd code is 100% right either) Jason