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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 B3652C432C3 for ; Wed, 13 Nov 2019 20:30:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 58D95206ED for ; Wed, 13 Nov 2019 20:30:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="K3ELKy0L" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727022AbfKMUaz (ORCPT ); Wed, 13 Nov 2019 15:30:55 -0500 Received: from hqemgate14.nvidia.com ([216.228.121.143]:5469 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726270AbfKMUax (ORCPT ); Wed, 13 Nov 2019 15:30:53 -0500 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate14.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Wed, 13 Nov 2019 12:30:51 -0800 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Wed, 13 Nov 2019 12:30:48 -0800 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Wed, 13 Nov 2019 12:30:48 -0800 Received: from [10.2.160.107] (172.20.13.39) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Wed, 13 Nov 2019 20:30:47 +0000 Subject: Re: [PATCH v3 00/23] mm/gup: track dma-pinned pages: FOLL_PIN, FOLL_LONGTERM To: Jan Kara , Jason Gunthorpe , Andrew Morton , Al Viro , Alex Williamson , Benjamin Herrenschmidt , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Christoph Hellwig , Dan Williams , Dave Chinner , David Airlie , "David S . Miller" , Ira Weiny , Jens Axboe , Jonathan Corbet , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Magnus Karlsson , Mauro Carvalho Chehab , Michael Ellerman , Michal Hocko , Mike Kravetz , Paul Mackerras , Shuah Khan , Vlastimil Babka , bpf , dri-devel , , , Linux Doc Mailing List , , "open list:KERNEL SELFTEST FRAMEWORK" , "open list:DMA BUFFER SHARING FRAMEWORK" , , linuxppc-dev , netdev , Linux MM , LKML References: <20191112000700.3455038-1-jhubbard@nvidia.com> <20191112203802.GD5584@ziepe.ca> <02fa935c-3469-b766-b691-5660084b60b9@nvidia.com> <7b671bf9-4d94-f2cc-8453-863acd5a1115@nvidia.com> <20191113101210.GD6367@quack2.suse.cz> <20191113114311.GP23790@phenom.ffwll.local> From: John Hubbard X-Nvconfidentiality: public Message-ID: <283b121d-f526-f43f-de45-dc2f8318d860@nvidia.com> Date: Wed, 13 Nov 2019 12:28:02 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20191113114311.GP23790@phenom.ffwll.local> X-Originating-IP: [172.20.13.39] X-ClientProxiedBy: HQMAIL107.nvidia.com (172.20.187.13) To HQMAIL107.nvidia.com (172.20.187.13) Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1573677051; bh=w2mV+XepuxnOtihiYgL/XuqwUYU2QI7jYfF/MppVAWE=; h=X-PGP-Universal:Subject:To:References:From:X-Nvconfidentiality: Message-ID:Date:User-Agent:MIME-Version:In-Reply-To: X-Originating-IP:X-ClientProxiedBy:Content-Type:Content-Language: Content-Transfer-Encoding; b=K3ELKy0LEaE4Frm6QQ4jLw8cJF3zobatTYiyQ/Vg2jO630IkqTksnY4sEeXMrgt5a b46qAh7TsgPVJKCPcTPIoUnjxNn6h2xUdpivOkXuz3queuSeoxqaSFBxc3yHdAdKf1 weqLMTvKu8Vs4tf6la1SbXQc5ZvBvuc6pK240FvHmEYJ0o2WePNqZANag+FSCa5U1i 2iyzSKadjF0T/uRVrR4KM4Ey20Bg7sJaaQBcaSS9Pr1q7odGMaBmeJ4hRBriIHKA4P 1LTpfohPn7iHAuSCtXbApQkiiVLKyUBXMKbsJDCLOd3JNZEji1iUk1dM5atghZtAzC EJVJspvV4f3sw== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/13/19 3:43 AM, Daniel Vetter wrote: ... >>>> Can't we call this unpin_user_page then, for some symmetry? Or is that >>>> even more churn? >>>> >>>> Looking from afar the naming here seems really confusing. >>> >>> >>> That look from afar is valuable, because I'm too close to the problem to see >>> how the naming looks. :) >>> >>> unpin_user_page() sounds symmetrical. It's true that it would cause more >>> churn (which is why I started off with a proposal that avoids changing the >>> names of put_user_page*() APIs). But OTOH, the amount of churn is proportional >>> to the change in direction here, and it's really only 10 or 20 lines changed, >>> in the end. >>> >>> So I'm open to changing to that naming. It would be nice to hear what others >>> prefer, too... >> >> FWIW I'd find unpin_user_page() also better than put_user_page() as a >> counterpart to pin_user_pages(). > > One more point from afar on pin/unpin: We use that a lot in graphics for > permanently pinned graphics buffer objects. Which really only should be > used for scanout. So at least graphics folks should have an appropriate > mindset and try to make sure we don't overuse this stuff. > -Daniel > OK, Ira also likes "unpin", and so far no one has said *anything* in favor of the "put_user_page" names, so I think we have a winner! I'll change the names to unpin_user_page*(). thanks, -- John Hubbard NVIDIA