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 ACA92C021AA for ; Wed, 19 Feb 2025 15:30:02 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 38BFB280238; Wed, 19 Feb 2025 10:30:02 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 314F428022F; Wed, 19 Feb 2025 10:30:02 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1B54A280238; Wed, 19 Feb 2025 10:30:02 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id F184028022F for ; Wed, 19 Feb 2025 10:30:01 -0500 (EST) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 2EEC180F55 for ; Wed, 19 Feb 2025 15:29:57 +0000 (UTC) X-FDA: 83137079634.20.2683906 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf23.hostedemail.com (Postfix) with ESMTP id BA71614000E for ; Wed, 19 Feb 2025 15:29:54 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf23.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=1739978995; 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=EVWGxlgI3HkuubO3KzA9LtdHUm7o4X/dcPZ2he0BA8I=; b=lSTWdiTN3pHL1R/VNutGjZW47OR9/oyhQKON0kkqvI+1Hj1euUoooYe89vnL3L06tNFhYU p2YgtmQVSyGBvsdZwkipJ9yoCfCLduE38lmXMwy4lkNTCD8sI4HMYRIFhg50yvmuVxxaYy Y3uh1h51BirIqN3a9W0bEaxTlpbXrZo= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf23.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=1739978995; a=rsa-sha256; cv=none; b=llAaOJX2EtuywiO5cWTMLOI+/dJ/SXAXAzHWEY8XPjr7ZSCq71sJL7SD5YI46Lq7YqbXPV eSFFaEnuk2z4eQ3aFvM4k4MdXplHSYK+ZT9nOH+f8y7VnfUVtCTNyUJmywc74U9eCaIg7u XFWd82RpC3bIpJ1ei4vcJWugIBxTpbU= 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 149B8152B; Wed, 19 Feb 2025 07:30:12 -0800 (PST) Received: from [10.57.84.233] (unknown [10.57.84.233]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B000F3F59E; Wed, 19 Feb 2025 07:29:45 -0800 (PST) Message-ID: <6cdc1de1-f760-4084-8eae-102ca16fee20@arm.com> Date: Wed, 19 Feb 2025 15:29:44 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC v2 4/9] khugepaged: generalize alloc_charge_folio for mTHP support Content-Language: en-GB To: Nico Pache , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-mm@kvack.org Cc: anshuman.khandual@arm.com, catalin.marinas@arm.com, cl@gentwo.org, vbabka@suse.cz, mhocko@suse.com, apopple@nvidia.com, dave.hansen@linux.intel.com, will@kernel.org, baohua@kernel.org, jack@suse.cz, srivatsa@csail.mit.edu, haowenchao22@gmail.com, hughd@google.com, aneesh.kumar@kernel.org, yang@os.amperecomputing.com, peterx@redhat.com, ioworker0@gmail.com, wangkefeng.wang@huawei.com, ziy@nvidia.com, jglisse@google.com, surenb@google.com, vishal.moola@gmail.com, zokeefe@google.com, zhengqi.arch@bytedance.com, jhubbard@nvidia.com, 21cnbao@gmail.com, willy@infradead.org, kirill.shutemov@linux.intel.com, david@redhat.com, aarcange@redhat.com, raquini@redhat.com, dev.jain@arm.com, sunnanyong@huawei.com, usamaarif642@gmail.com, audra@redhat.com, akpm@linux-foundation.org, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, tiwai@suse.de References: <20250211003028.213461-1-npache@redhat.com> <20250211003028.213461-5-npache@redhat.com> From: Ryan Roberts In-Reply-To: <20250211003028.213461-5-npache@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: BA71614000E X-Stat-Signature: pdgkutx96eg4bz6kr71yapsyod9pxknp X-HE-Tag: 1739978994-708907 X-HE-Meta: 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 V6PeFN1R FOI1FHslNXuBbUzlixwoTg2Zpc9IbuaCviYA+GTtXdo5/PfUD8oeUOkxdXSvUPN16ETzWKjxzd6GUuF0fCVRx9kNPdsivIWOpxktqixBVP2+6sg4W4abC9N9CZ2twpTlLhogCQ3bAM6157q9/TUtRmRUvVVw+G4ihKO/OttyUihHWcBuDjZ/p5HorSD/e865qzV6V+gJ5ULb0VR6gGqTgAl60j1YRR4P6r3TClbbIlkrBSjTA/13yx/06E2psOOctIWoMiCDfoefHuIwnhTlBaj8kEW7iMoM2YmFo 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: List-Subscribe: List-Unsubscribe: On 11/02/2025 00:30, Nico Pache wrote: > alloc_charge_folio allocates the new folio for the khugepaged collapse. > Generalize the order of the folio allocations to support future mTHP > collapsing. > > No functional changes in this patch. > > Signed-off-by: Nico Pache > --- > mm/khugepaged.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index c834ea842847..0cfcdc11cabd 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -1074,14 +1074,14 @@ static int __collapse_huge_page_swapin(struct mm_struct *mm, > } > > static int alloc_charge_folio(struct folio **foliop, struct mm_struct *mm, > - struct collapse_control *cc) > + struct collapse_control *cc, int order) > { > gfp_t gfp = (cc->is_khugepaged ? alloc_hugepage_khugepaged_gfpmask() : > GFP_TRANSHUGE); > int node = khugepaged_find_target_node(cc); > struct folio *folio; > > - folio = __folio_alloc(gfp, HPAGE_PMD_ORDER, node, &cc->alloc_nmask); > + folio = __folio_alloc(gfp, order, node, &cc->alloc_nmask); > if (!folio) { > *foliop = NULL; > count_vm_event(THP_COLLAPSE_ALLOC_FAILED); Stats management is different for PMD-sized THP vs mTHP. All the PMD-sized THP stats continue to be accumulated in /proc/meminfo (or whatever its called). Other THP sizes are not accounted here. All mTHP sizes (*including* PMD-sized) should accounted in /sys/kernel/mm/transparent_hugepage/hugepages-kB/stats/*. There is a file for each stat. We decided to do it this way for fear of breaking unenlightened user space that only understands PMD-sized THP. You can find the mTHP stats machinery at count_mthp_stat(). > @@ -1125,7 +1125,7 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, > */ > mmap_read_unlock(mm); > > - result = alloc_charge_folio(&folio, mm, cc); > + result = alloc_charge_folio(&folio, mm, cc, HPAGE_PMD_ORDER); > if (result != SCAN_SUCCEED) > goto out_nolock; > > @@ -1851,7 +1851,7 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, > VM_BUG_ON(!IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && !is_shmem); > VM_BUG_ON(start & (HPAGE_PMD_NR - 1)); > > - result = alloc_charge_folio(&new_folio, mm, cc); > + result = alloc_charge_folio(&new_folio, mm, cc, HPAGE_PMD_ORDER); > if (result != SCAN_SUCCEED) > goto out; >