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=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 33A33C3A5A1 for ; Thu, 22 Aug 2019 18:17:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0CB4821848 for ; Thu, 22 Aug 2019 18:17:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387901AbfHVSRO (ORCPT ); Thu, 22 Aug 2019 14:17:14 -0400 Received: from mx2.suse.de ([195.135.220.15]:58740 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725893AbfHVSRO (ORCPT ); Thu, 22 Aug 2019 14:17:14 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 9EB42ADF0; Thu, 22 Aug 2019 18:17:11 +0000 (UTC) Date: Thu, 22 Aug 2019 11:17:01 -0700 From: Davidlohr Bueso To: Michel Lespinasse Cc: mingo@kernel.org, tglx@linutronix.de, peterz@infradead.org, akpm@linux-foundation.org, x86@kernel.org, linux-kernel@vger.kernel.org, Davidlohr Bueso Subject: Re: [PATCH 1/3] x86,mm/pat: Use generic interval trees Message-ID: <20190822181701.zhfdkjbwjh56i3ax@linux-r8p5> References: <20190813224620.31005-1-dave@stgolabs.net> <20190813224620.31005-2-dave@stgolabs.net> <20190821215707.GA99147@google.com> <20190822044936.qusm5zgjdf6n5fds@linux-r8p5> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20190822044936.qusm5zgjdf6n5fds@linux-r8p5> User-Agent: NeoMutt/20180323 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >On Wed, 21 Aug 2019, Michel Lespinasse wrote: >>As I had commented some time ago, I wish the interval trees used [start,end) >>intervals instead of [start,last] - it would be a better fit for basically >>all of the current interval tree users. So the vma_interval_tree (which is a pretty important user) tends to break this pattern, as most lookups are [a,a]. We would have to update most of the vma_interval_tree_foreach calls, for example, to now do [a,a+1[ such that we don't break things. Some cases for the anon_vma_tree as well (ie memory-failure). I'm not sure anymore it's worth going down this path as we end up exchanging one hack for another (and the vma_interval_tree is a pretty big user); but I'm sure you're aware of this and thus disagree. Thanks, Davidlohr