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=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 2B7ECCA9EB5 for ; Mon, 4 Nov 2019 20:48:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0306020B7C for ; Mon, 4 Nov 2019 20:48:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hQ9+wUcl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729602AbfKDUsp (ORCPT ); Mon, 4 Nov 2019 15:48:45 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:49423 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729551AbfKDUso (ORCPT ); Mon, 4 Nov 2019 15:48:44 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1572900523; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=mn5RsMcwjgSz4Uc3SsLk9u7OdhxITCoqvev72K3k0/w=; b=hQ9+wUclM/gzvrwXlA0dBmvh/ki8tPcPI4NMrzUSwOoLjc6TTXi4ppLn6A8JYvsmhSCT/q 9xJ9ZYZR1XsNeEJ6PbCbPyMze2ZLL00duT3IgVl7S51Ld6Zf0Dtf0e8LS6qh+AhfwtBiPB MvLGtYW2tZJFAys78ar8r6R6dU8re+M= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-261-XtiEJ6MJOtixJceTBvorsw-1; Mon, 04 Nov 2019 15:48:39 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 279BB1800DFD; Mon, 4 Nov 2019 20:48:35 +0000 (UTC) Received: from redhat.com (unknown [10.20.6.178]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AEACB5C3F8; Mon, 4 Nov 2019 20:48:29 +0000 (UTC) Date: Mon, 4 Nov 2019 15:48:28 -0500 From: Jerome Glisse To: David Rientjes Cc: John Hubbard , Andrew Morton , Al Viro , Alex Williamson , Benjamin Herrenschmidt , =?iso-8859-1?Q?Bj=F6rn_T=F6pel?= , Christoph Hellwig , Dan Williams , Daniel Vetter , Dave Chinner , David Airlie , "David S . Miller" , Ira Weiny , Jan Kara , Jason Gunthorpe , Jens Axboe , Jonathan Corbet , Magnus Karlsson , Mauro Carvalho Chehab , Michael Ellerman , Michal Hocko , Mike Kravetz , Paul Mackerras , Shuah Khan , Vlastimil Babka , bpf@vger.kernel.org, dri-devel@lists.freedesktop.org, kvm@vger.kernel.org, linux-block@vger.kernel.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-media@vger.kernel.org, linux-rdma@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, linux-mm@kvack.org, LKML Subject: Re: [PATCH v2 05/18] mm/gup: introduce pin_user_pages*() and FOLL_PIN Message-ID: <20191104204828.GC7731@redhat.com> References: <20191103211813.213227-1-jhubbard@nvidia.com> <20191103211813.213227-6-jhubbard@nvidia.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-MC-Unique: XtiEJ6MJOtixJceTBvorsw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 04, 2019 at 12:33:09PM -0800, David Rientjes wrote: >=20 >=20 > On Sun, 3 Nov 2019, John Hubbard wrote: >=20 > > Introduce pin_user_pages*() variations of get_user_pages*() calls, > > and also pin_longterm_pages*() variations. > >=20 > > These variants all set FOLL_PIN, which is also introduced, and > > thoroughly documented. > >=20 > > The pin_longterm*() variants also set FOLL_LONGTERM, in addition > > to FOLL_PIN: > >=20 > > pin_user_pages() > > pin_user_pages_remote() > > pin_user_pages_fast() > >=20 > > pin_longterm_pages() > > pin_longterm_pages_remote() > > pin_longterm_pages_fast() > >=20 > > All pages that are pinned via the above calls, must be unpinned via > > put_user_page(). > >=20 >=20 > Hi John, >=20 > I'm curious what consideration is given to what pageblock migrate types= =20 > that FOLL_PIN and FOLL_LONGTERM pages originate from, assuming that=20 > longterm would want to originate from MIGRATE_UNMOVABLE pageblocks for th= e=20 > purposes of anti-fragmentation? We do not control page block, GUP can happens on _any_ page that is map inside a process (anonymous private vma or regular file back one). Cheers, J=E9r=F4me