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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 59614C61D97 for ; Fri, 24 Nov 2023 15:14:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=jGZxJvQ7NBF76TUUVPEs0LU3zqJLsb/peAzNxEHfugM=; b=jkqkT2iO03vfP3 zTrqQ75xbGQsaW2FVkrU50hcbJN4BDVAYdCrPWPZsy9aCffQ1qb/ARLAmB1g65fjc1jYFrMnnlB5X CExQGuPt096QYs6skf5uaIUHR3JrVbj3lIUW+B75ASEcfu2fjh68XdajmA/ocZsDdXkX57ORGfTan O6P5PFQzYJnzJBiPoUHuiGdcW8SgU9rVVRSpvrYWPjWN+Owxj5twwlGT3LFCRyAh0GFb4d3BZjJ/M bJhuKZTOUp6bA/syYDmfeIMidNk+Vu6QI+WPaJHurKsVxFtopJpZMowGsyqP0YHC8DEceeFQ/WTC4 v86f0GCEaW6NI63ifuLw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1r6Xs8-007W4n-17; Fri, 24 Nov 2023 15:13:36 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1r6Xs6-007W4e-1R for linux-arm-kernel@bombadil.infradead.org; Fri, 24 Nov 2023 15:13:34 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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; bh=cpGcQbK5ALS/h/233m+c8jmOxYiT52WHP0nU+fSEvDI=; b=fX93P2C7tTpexgPCsWNuQcuoF5 V4NbDi/cjiBJ3iFD2y4kQwA8+IY1jUY//C5gTL7Y8jlJWwizOacgMGtmLWvpyP1Jxtmlv8KsF+u2Q 3AFGeeshrZuDXwCFRYI7nDjjzh5ZrGTMMIUvezBHV4zBK0vJKDx0VZIpALBPKeA84BikUEgoitHmR deGOVtSFkgHm/2kSyrhYPGpPu5pc1VH0zHdq1nq6ZFG84alWCsKV9908uETUg2hAyPf5y4SR2mvzr 6bWeourxF/Pzo9Zfk32xV0m0+CJWq9as/ots/slGIkFbbfZPP1/KgynAsP/vY1Aix+BJgIpgbC0sJ +O0DhaJQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1r6Xrz-008gyc-Bo; Fri, 24 Nov 2023 15:13:27 +0000 Date: Fri, 24 Nov 2023 15:13:27 +0000 From: Matthew Wilcox To: Ryan Roberts Cc: Andrew Morton , Yin Fengwei , David Hildenbrand , Yu Zhao , Catalin Marinas , Anshuman Khandual , Yang Shi , "Huang, Ying" , Zi Yan , Luis Chamberlain , Itaru Kitayama , "Kirill A. Shutemov" , John Hubbard , David Rientjes , Vlastimil Babka , Hugh Dickins , Kefeng Wang , linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [RESEND PATCH v7 00/10] Small-sized THP for anonymous memory Message-ID: References: <20231122162950.3854897-1-ryan.roberts@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Nov 24, 2023 at 09:56:37AM +0000, Ryan Roberts wrote: > On 23/11/2023 15:59, Matthew Wilcox wrote: > > On Wed, Nov 22, 2023 at 04:29:40PM +0000, Ryan Roberts wrote: > >> This is v7 of a series to implement small-sized THP for anonymous memory > >> (previously called "large anonymous folios"). The objective of this is to > > > > I'm still against small-sized THP. We've now got people asking whether > > the THP counters should be updated when dealing with large folios that > > are smaller than PMD sized. It's sowing confusion, and we should go > > back to large anon folios as a name. > > I suspect I'm labouring the point here, but I'd like to drill into exactly what > you are objecting to. Is it: > > A) Using the name "small-sized THP" (which is currently only used in the commit > logs and a couple of times in the documentation). Yes, this is what I'm objecting to. > B) Exposing the controls for this feature as an extension to the existing > /sys/kernel/mm/transparent_hugepage/* sysfs interface (note the interface never > uses the term "small-sized"). I don't object to the controls being here. I still wish we didn't need an interface to control them at all, but I don't have the time to become an expert in anonymous memory and figure out how to make that happen. > If A) then this is easily solved by choosing another descriptive name and > updating those places. Personally I think it would be best to continue to use > "THP" since we are exposing the feature through that interface. Perhaps "large > folio THP". I think that continues the confusion about the existing interfaces we have which count THP (and mean "PMD sized THP"). I'd really prefer the term "THP" to unambiguously mean PMD sized THP. I don't understand why you felt the need to move away from Large Anon Folios as a name. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel