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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id BB386E7849A for ; Mon, 2 Oct 2023 10:15:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3BF806B013D; Mon, 2 Oct 2023 06:15:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 36E816B015D; Mon, 2 Oct 2023 06:15:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 25D5B6B015E; Mon, 2 Oct 2023 06:15:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 183D96B013D for ; Mon, 2 Oct 2023 06:15:30 -0400 (EDT) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id E08F31C9CE5 for ; Mon, 2 Oct 2023 10:15:29 +0000 (UTC) X-FDA: 81300114378.23.3741396 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf05.hostedemail.com (Postfix) with ESMTP id 06C33100010 for ; Mon, 2 Oct 2023 10:15:26 +0000 (UTC) Authentication-Results: imf05.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf05.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1696241727; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WYZiRWjT8ACmWX80JyIx3xULa5kEBOVG4FdJ6eVn6qA=; b=UjitC2rXRtEZqGiGso8iq6wFcx6/Nt5aNy/BZwtfhcDnYCVqgRrrsGhQSyZEk4Pzvr6wi0 m6CPbUsH1Agd+QITGxOTcl9B6LOyrEolnCDqqv7vhz4Nyktsmy7y81E1hjiC6+qV77C720 ePMzjRKYVlXS0SC1jSwOFZbw7rIsMKw= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf05.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1696241727; a=rsa-sha256; cv=none; b=qL4pNVm3Q9NXLmLObUhZXgmWdKZY5VJEIebWBNjECjAs4onn2AyAPj8Xqzl8mncOJUHRJJ VBL0h9xa5JLCdJje1aXvTsn+YFh3gQ2FC9+T3Olvkt0Lyd8xWDuCj20HCt0t96R6Czq0/e fwO4bk0Qf6GUTuP6fYCN4xJ2U06sWtI= 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 52724C15; Mon, 2 Oct 2023 03:16:04 -0700 (PDT) Received: from [10.57.66.79] (unknown [10.57.66.79]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8A3983F762; Mon, 2 Oct 2023 03:15:22 -0700 (PDT) Message-ID: <3fabc0ed-9f2e-4ad6-ac40-aabdacff1cf2@arm.com> Date: Mon, 2 Oct 2023 11:15:20 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 4/9] mm: thp: Introduce anon_orders and anon_always_mask sysfs files Content-Language: en-GB To: Andrew Morton Cc: Matthew Wilcox , 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 , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org References: <20230929114421.3761121-1-ryan.roberts@arm.com> <20230929114421.3761121-5-ryan.roberts@arm.com> <20230929155530.a51e68e03e47a06b6b84c689@linux-foundation.org> From: Ryan Roberts In-Reply-To: <20230929155530.a51e68e03e47a06b6b84c689@linux-foundation.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 06C33100010 X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: s6b9hfcu9cb19ekgd1bnt9fdzy1xhqor X-HE-Tag: 1696241726-76239 X-HE-Meta: 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 HvhK6ggH oEGRdjH4AVzP1xTqlnGUNZalx+oG0DQUi2pbRMJ7TwXMDrpkvbf5vHsSCfXSqJfJVE9DZFqqvmIrP2jwOty+xJjI3uZ3PXqyQ39rjs/luX3KPuWW7uHZNNovs6WKGBi238DT2YJhymLOILSxnunN91gWg4ifYdGlQ8xG/EwKxFWMeaflJmrDjbQRB9v8XIR+jxOz0U0Z6UzPHqufvOFFrDmJNqoTUdF2+hsQawg+EDPdTo1FydhMrbn23+282uU7Ywv18YWJNO2YUd6AbPNacIVfYPqTKxx3lcQF0DUEG5LIdQm9dXfzpf7WfjhFpPow9x8+q/I086lU1pwE= 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 29/09/2023 23:55, Andrew Morton wrote: > On Fri, 29 Sep 2023 12:44:15 +0100 Ryan Roberts wrote: > >> In preparation for adding support for anonymous large folios that are >> smaller than the PMD-size, introduce 2 new sysfs files that will be used >> to control the new behaviours via the transparent_hugepage interface. >> For now, the kernel still only supports PMD-order anonymous THP, so when >> reading back anon_orders, it will reflect that. Therefore there are no >> behavioural changes intended here. > > powerpc strikes again. ARCH=powerpc allmodconfig: > > > In file included from ./include/linux/bits.h:6, > from ./include/linux/ratelimit_types.h:5, > from ./include/linux/printk.h:9, > from ./include/asm-generic/bug.h:22, > from ./arch/powerpc/include/asm/bug.h:116, > from ./include/linux/bug.h:5, > from ./include/linux/mmdebug.h:5, > from ./include/linux/mm.h:6, > from mm/huge_memory.c:8: > ./include/vdso/bits.h:7:33: error: initializer element is not constant > 7 | #define BIT(nr) (UL(1) << (nr)) > | ^ > mm/huge_memory.c:77:47: note: in expansion of macro 'BIT' > 77 | unsigned int huge_anon_orders __read_mostly = BIT(PMD_ORDER); > | ^~~ Ahh my bad, sorry about that - I built various configs and arches but not powerpc. > > We keep tripping over this. I wish there was a way to fix it. > > > > Style whine: an all-caps identifier is supposed to be a constant, > dammit. > > #define PTE_INDEX_SIZE __pte_index_size > > Nope. > > > > I did this: > > --- a/mm/huge_memory.c~mm-thp-introduce-anon_orders-and-anon_always_mask-sysfs-files-fix > +++ a/mm/huge_memory.c > @@ -74,7 +74,7 @@ static unsigned long deferred_split_scan > static atomic_t huge_zero_refcount; > struct page *huge_zero_page __read_mostly; > unsigned long huge_zero_pfn __read_mostly = ~0UL; > -unsigned int huge_anon_orders __read_mostly = BIT(PMD_ORDER); > +unsigned int huge_anon_orders __read_mostly; > static unsigned int huge_anon_always_mask __read_mostly; > > /** > @@ -528,6 +528,9 @@ static int __init hugepage_init_sysfs(st > { > int err; > > + /* powerpc's PMD_ORDER isn't a compile-time constant */ > + huge_anon_orders = BIT(PMD_ORDER); > + > *hugepage_kobj = kobject_create_and_add("transparent_hugepage", mm_kobj); > if (unlikely(!*hugepage_kobj)) { > pr_err("failed to create transparent hugepage kobject\n"); > _ > > > I assume this is set up early enough. Yes this should be fine. > > I don't know why powerpc's PTE_INDEX_SIZE is variable. Hopefully it > has been set up by this time and it won't get altered. Looks that way from the code; its set during early_init_mmu(). Anyway, I'll take the fix into my next spin if I need to do one. I see you've taken it into mm-unstable - thanks! But given I'm introducing UABI, I was expecting some comments and a probably need for a new rev. I'd like to think we are getting there though. Thanks, Ryan