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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B787DC4167B for ; Tue, 28 Nov 2023 12:15:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344632AbjK1MPe (ORCPT ); Tue, 28 Nov 2023 07:15:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49560 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344302AbjK1MPd (ORCPT ); Tue, 28 Nov 2023 07:15:33 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 5104F183 for ; Tue, 28 Nov 2023 04:15:39 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E44DCC15; Tue, 28 Nov 2023 04:16:25 -0800 (PST) Received: from [10.1.33.188] (XHFQ2J9959.cambridge.arm.com [10.1.33.188]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E69273F73F; Tue, 28 Nov 2023 04:15:32 -0800 (PST) Message-ID: <58af512c-3d7d-4774-88f7-6336c9384b61@arm.com> Date: Tue, 28 Nov 2023 12:15:30 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RESEND PATCH v7 00/10] Small-sized THP for anonymous memory Content-Language: en-GB To: David Hildenbrand , John Hubbard , Alistair Popple Cc: Matthew Wilcox , Andrew Morton , Yin Fengwei , Yu Zhao , Catalin Marinas , Anshuman Khandual , Yang Shi , "Huang, Ying" , Zi Yan , Luis Chamberlain , Itaru Kitayama , "Kirill A. Shutemov" , David Rientjes , Vlastimil Babka , Hugh Dickins , Kefeng Wang , linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20231122162950.3854897-1-ryan.roberts@arm.com> <9c8f6d2a-7ed8-45d2-9684-d77489bd99b8@redhat.com> <26c361bc-6d87-4a57-9fae-ef635c9039c7@redhat.com> <87sf4rppuc.fsf@nvdebian.thelocal> <51e6c9f1-e863-464b-b5f3-d7f60a7ebed6@arm.com> From: Ryan Roberts In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 28/11/2023 08:48, David Hildenbrand wrote: > >>> >>> Agreed. We are bikeshedding here. But if we really can't swallow "small-sized >>> THP" then perhaps the most efficient way to move this forwards is to review the >>> documentation (where "small-sized THP" appears twice in order to differentiate >>> from PMD-sized THP) - its in patch 3. Perhaps it will be easier to come up with >>> a good description in the context of those prose? Then once we have that, >>> hopefully a term will fall out that I'll update the commit logs with. >>> >> >> I will see you over in patch 3, then. I've already looked at it and am going >> to suggest a long and a short name. The long name is for use in comments and >> documentation, and the short name is for variable fragments: >> >>       Long name:  "pte-mapped THPs" >>       Short names: pte_thp, or pte-thp > > The issue is that any THP can be pte-mapped, even a PMD-sized THP. However, the > "natural" way to map a PMD-sized THP is using a PMD. > How about we just stop trying to come up with a term for the "small-sized THP" vs "PMD-sized THP" and instead invent a name that covers ALL THP: "multi-size THP" vs "PMD-sized THP". Then in the docs we can talk about how multi-size THP introduces the ability to allocate memory in blocks that are bigger than a base page but smaller than traditional PMD-size, in increments of a power-of-2 number of pages.