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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 0E896C43381 for ; Wed, 20 Feb 2019 15:21:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D3A9120880 for ; Wed, 20 Feb 2019 15:21:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="WIGucUyB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727522AbfBTPU7 (ORCPT ); Wed, 20 Feb 2019 10:20:59 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:37016 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726224AbfBTPU5 (ORCPT ); Wed, 20 Feb 2019 10:20:57 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=EFeifr+GfaKqX300Um+mjNzD3Rm1S0esXSt0B9w2YGY=; b=WIGucUyBjsGVWuL2jvGEP36J7 wAIM66Nws+XW3bCRdl88lmFalND8Uqloj60hjuL97/UwAqCvwAh/q71HAghQoAiJxUBKDV4NeFs+P HVl2PIkFym1snOkp7H0Bh7Iwy3HNth61esVAhkupONHYlLPFOyNBcP6ioDPUrT9m8HmSlz0Cy7brW T3CThrxzbkECUC+LLP/75uJ0vWxiD0QDLR28VwL+hwhNu5iUxu99KR6fznvbiQWa2uKqaDKSSWHwd 5uLNPR4nLxuoKU8lEnZ+ly+ElHLeYkLQbpv5lMqHn24WHv224i/dDaYfT4EtkA5c0+hIF01oAUZ5T N7tedkzRQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gwTek-00048O-OH; Wed, 20 Feb 2019 15:19:30 +0000 Date: Wed, 20 Feb 2019 07:19:30 -0800 From: Christoph Hellwig To: ira.weiny@intel.com Cc: John Hubbard , Andrew Morton , 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 , Paul Burton , James Hogan , linux-kernel@vger.kernel.org, linux-mm@kvack.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, kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, linux-fpga@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-scsi@vger.kernel.org, devel@driverdev.osuosl.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-fbdev@vger.kernel.org, xen-devel@lists.xenproject.org, devel@lists.orangefs.org, ceph-devel@vger.kernel.org, rds-devel@oss.oracle.com Subject: Re: [RESEND PATCH 0/7] Add FOLL_LONGTERM to GUP fast and use it Message-ID: <20190220151930.GB11695@infradead.org> References: <20190220053040.10831-1-ira.weiny@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190220053040.10831-1-ira.weiny@intel.com> User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Feb 19, 2019 at 09:30:33PM -0800, ira.weiny@intel.com wrote: > From: Ira Weiny > > Resending these as I had only 1 minor comment which I believe we have covered > in this series. I was anticipating these going through the mm tree as they > depend on a cleanup patch there and the IB changes are very minor. But they > could just as well go through the IB tree. > > NOTE: This series depends on my clean up patch to remove the write parameter > from gup_fast_permitted()[1] > > 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 of FS DAX pages. This I don't get - if you do lock down long term mappings performance of the actual get_user_pages call shouldn't matter to start with. What do I miss?