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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 EC8F7C43381 for ; Tue, 19 Mar 2019 22:19:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A072D2175B for ; Tue, 19 Mar 2019 22:19:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553033974; bh=CWHoK7+ryr2wxJvutZimA/AdCYmtRDG/YpvaeB9T8uM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=s+NpLfFuO2cjOwy9poOxk/vR6xD0ecqt7oUuejpa8axZPirj7/9kMnkI8plVwk+xA 8RPjGVioeUzrilehPwZRoUqj9OpZx+XKAYI5HV+4r7vtY0C0bajCHVqgnVb6VRKzny 6Z9ag+o4fhzBHCTxMbLlexKFBEvZAzDL4Bs3REmc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726933AbfCSWTe (ORCPT ); Tue, 19 Mar 2019 18:19:34 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:53568 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726851AbfCSWTe (ORCPT ); Tue, 19 Mar 2019 18:19:34 -0400 Received: from akpm3.svl.corp.google.com (unknown [104.133.8.65]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id C3ACB3DA8; Tue, 19 Mar 2019 22:19:31 +0000 (UTC) Date: Tue, 19 Mar 2019 15:19:30 -0700 From: Andrew Morton To: ira.weiny@intel.com Cc: John Hubbard , Michal Hocko , "Kirill A. Shutemov" , Peter Zijlstra , Jason Gunthorpe , Benjamin Herrenschmidt , Paul Mackerras , "David S. Miller" , Martin Schwidefsky , Heiko Carstens , Rich Felker , Yoshinori Sato , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Ralf Baechle , James Hogan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-rdma@vger.kernel.org, netdev@vger.kernel.org, Dan Williams Subject: Re: [RESEND PATCH 0/7] Add FOLL_LONGTERM to GUP fast and use it Message-Id: <20190319151930.bab575d62fb1a33094160fe3@linux-foundation.org> In-Reply-To: <20190317183438.2057-1-ira.weiny@intel.com> References: <20190317183438.2057-1-ira.weiny@intel.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Sun, 17 Mar 2019 11:34:31 -0700 ira.weiny@intel.com wrote: > Resending after rebasing to the latest mm tree. > > HFI1, qib, and mthca, use get_user_pages_fast() due to it performance > advantages. These pages can be held for a significant time. But > get_user_pages_fast() does not protect against mapping FS DAX pages. > > Introduce FOLL_LONGTERM and use this flag in get_user_pages_fast() which > retains the performance while also adding the FS DAX checks. XDP has also > shown interest in using this functionality.[1] > > In addition we change get_user_pages() to use the new FOLL_LONGTERM flag and > remove the specialized get_user_pages_longterm call. It would be helpful to include your response to Christoph's question (http://lkml.kernel.org/r/20190220180255.GA12020@iweiny-DESK2.sc.intel.com) in the changelog. Because if one person was wondering about this, others will likely do so. We have no record of acks or reviewed-by's. At least one was missed (http://lkml.kernel.org/r/CAOg9mSTTcD-9bCSDfC0WRYqfVrNB4TwOzL0c4+6QXi-N_Y43Vw@mail.gmail.com), but that is very very partial. This patchset is fairly DAX-centered, but Dan wasn't cc'ed! So ho hum. I'll scoop them up and shall make the above changes to the [1/n] changelog, but we still have some work to do.