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=-2.2 required=3.0 tests=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 EF9CBC4332B for ; Sat, 21 Mar 2020 08:40:15 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C49DB20753 for ; Sat, 21 Mar 2020 08:40:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C49DB20753 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 5401C6B0007; Sat, 21 Mar 2020 04:40:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4EFD36B0008; Sat, 21 Mar 2020 04:40:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 454406B000A; Sat, 21 Mar 2020 04:40:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0097.hostedemail.com [216.40.44.97]) by kanga.kvack.org (Postfix) with ESMTP id 31A666B0007 for ; Sat, 21 Mar 2020 04:40:15 -0400 (EDT) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id AE623180AD81D for ; Sat, 21 Mar 2020 08:40:14 +0000 (UTC) X-FDA: 76618722348.21.rule84_218026da7612 X-HE-Tag: rule84_218026da7612 X-Filterd-Recvd-Size: 1774 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by imf31.hostedemail.com (Postfix) with ESMTP for ; Sat, 21 Mar 2020 08:40:14 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 88FF168AFE; Sat, 21 Mar 2020 09:40:12 +0100 (CET) Date: Sat, 21 Mar 2020 09:40:12 +0100 From: Christoph Hellwig To: Jason Gunthorpe Cc: Jerome Glisse , Ralph Campbell , Felix.Kuehling@amd.com, linux-mm@kvack.org, John Hubbard , dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, Christoph Hellwig , Philip Yang , Jason Gunthorpe Subject: Re: [PATCH hmm 4/6] mm/hmm: remove HMM_FAULT_SNAPSHOT Message-ID: <20200321084012.GD28695@lst.de> References: <20200320164905.21722-1-jgg@ziepe.ca> <20200320164905.21722-5-jgg@ziepe.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200320164905.21722-5-jgg@ziepe.ca> User-Agent: Mutt/1.5.17 (2007-11-01) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Mar 20, 2020 at 01:49:03PM -0300, Jason Gunthorpe wrote: > + struct hmm_range *range = hmm_vma_walk->range; > unsigned int required_fault = 0; > unsigned long i; > > - if (hmm_vma_walk->flags & HMM_FAULT_SNAPSHOT) > + /* > + * If there is no way for valid to be set in hmm_pte_need_fault() then > + * don't bother to call it. > + */ > + if (!(((range->flags[HMM_PFN_VALID] & range->pfn_flags_mask) | > + range->default_flags) & > + range->flags[HMM_PFN_VALID])) I think this needs to be split out into a well documented helper function, as it is pretty much unreadable all cramed into a complex conditional.