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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 10302C0650F for ; Thu, 8 Aug 2019 22:21:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BEF9C2173C for ; Thu, 8 Aug 2019 22:21:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=shipmail.org header.i=@shipmail.org header.b="Js30zXpc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404632AbfHHWVb (ORCPT ); Thu, 8 Aug 2019 18:21:31 -0400 Received: from pio-pvt-msa1.bahnhof.se ([79.136.2.40]:49724 "EHLO pio-pvt-msa1.bahnhof.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404589AbfHHWVa (ORCPT ); Thu, 8 Aug 2019 18:21:30 -0400 Received: from localhost (localhost [127.0.0.1]) by pio-pvt-msa1.bahnhof.se (Postfix) with ESMTP id C00AF3F3CA; Fri, 9 Aug 2019 00:21:27 +0200 (CEST) Authentication-Results: pio-pvt-msa1.bahnhof.se; dkim=pass (1024-bit key; unprotected) header.d=shipmail.org header.i=@shipmail.org header.b="Js30zXpc"; dkim-atps=neutral X-Virus-Scanned: Debian amavisd-new at bahnhof.se Received: from pio-pvt-msa1.bahnhof.se ([127.0.0.1]) by localhost (pio-pvt-msa1.bahnhof.se [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id aL-YyBR6tXjE; Fri, 9 Aug 2019 00:21:26 +0200 (CEST) Received: from mail1.shipmail.org (h-205-35.A357.priv.bahnhof.se [155.4.205.35]) (Authenticated sender: mb878879) by pio-pvt-msa1.bahnhof.se (Postfix) with ESMTPA id CD18A3F398; Fri, 9 Aug 2019 00:21:25 +0200 (CEST) Received: from localhost.localdomain (h-205-35.A357.priv.bahnhof.se [155.4.205.35]) by mail1.shipmail.org (Postfix) with ESMTPSA id 16C1136015E; Fri, 9 Aug 2019 00:21:25 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=shipmail.org; s=mail; t=1565302885; bh=RVaCu1C5tAq3VjSBjXkZ1UBuhKLiLy/Tpb94K/nrtEA=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=Js30zXpcy30+ZBx1NEVIkzvBdlmXRihLBZvVid2tt64zg/qVBCw5XIppSy+A4/doJ S/Q+ly9RkbBXM53IERB8Qzr0uGGHeOvMLz8hKp5L7qJTDmfveaf3yO1s/0j0tOGStZ 5qDimRq6xCm3+fuzaPD+XJtHGufRdRJ3+QCW7L9g= Subject: Re: cleanup the walk_page_range interface To: Christoph Hellwig , Linus Torvalds Cc: Andrew Morton , Jerome Glisse , Jason Gunthorpe , Steven Price , Linux-MM , Linux List Kernel Mailing References: <20190808154240.9384-1-hch@lst.de> <20190808215632.GA12773@lst.de> From: Thomas Hellstrom Message-ID: Date: Fri, 9 Aug 2019 00:21:24 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190808215632.GA12773@lst.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/8/19 11:56 PM, Christoph Hellwig wrote: > On Thu, Aug 08, 2019 at 10:50:37AM -0700, Linus Torvalds wrote: >>> Note that both Thomas and Steven have series touching this area pending, >>> and there are a couple consumer in flux too - the hmm tree already >>> conflicts with this series, and I have potential dma changes on top of >>> the consumers in Thomas and Steven's series, so we'll probably need a >>> git tree similar to the hmm one to synchronize these updates. >> I'd be willing to just merge this now, if that helps. The conversion >> is mechanical, and my only slight worry would be that at least for my >> original patch I didn't build-test the (few) non-x86 >> architecture-specific cases. But I did end up looking at them fairly >> closely (basically using some grep/sed scripts to see that the >> conversions I did matched the same patterns). And your changes look >> like obvious improvements too where any mistake would have been caught >> by the compiler. > I did cross compile the s390 and powerpc bits, but I do not have an > openrisc compiler. > >> So I'm not all that worried from a functionality standpoint, and if >> this will help the next merge window, I'll happily pull now. > That would help with this series vs the others, but not with the other > series vs each other. Although my series doesn't touch the pagewalk code, it rather borrowed some concepts from it and used for the apply_to_page_range() interface. The reason being that the pagewalk code requires the mmap_sem to be held (mainly for trans-huge pages and reading the vma->vm_flags if I understand the code correctly). That is fine when you scan the vmas of a process, but the helpers I wrote need to instead scan all vmas pointing into a struct address_space, and taking the mmap_sem for each vma will create lock inversion problems. /Thomas