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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6F999C61DB9 for ; Thu, 27 Aug 2026 16:32:49 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5A3036B0088; Thu, 27 Aug 2026 12:32:48 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 57AA16B008A; Thu, 27 Aug 2026 12:32:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 491636B008C; Thu, 27 Aug 2026 12:32:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 1D4266B0088 for ; Thu, 27 Aug 2026 12:32:48 -0400 (EDT) Received: from smtpin13.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay03.hostedemail.com (Postfix) with ESMTP id A1993A0125 for ; Thu, 27 Aug 2026 16:32:47 +0000 (UTC) X-FDA: 85147593174.13.C78125B Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf12.hostedemail.com (Postfix) with ESMTP id B598340006 for ; Thu, 27 Aug 2026 16:32:45 +0000 (UTC) Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=nIcGb32m; spf=pass (imf12.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1787848365; b=R4Wz7cOySwKL4ac/rw4lN6zCFFRGFi/+kY3YSsdajksTfD2nOgtxjLMpvMuLWEBTyoUa5u S5PAjq9yo+IxX2W0Ysm0VGbhL7HnexkEHBJqZ1g2h9K/vUULYt0NpDDKwLConP467H5M4X 4IhM27upcjjpbFSZ5jVw+BsufwuwDAw= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=nIcGb32m; spf=pass (imf12.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1787848365; 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:dkim-signature; bh=O2H9pqs8u34SiJIXHKDFq+rwx9sPKmCRJst1ewdjsNw=; b=DT90wroDtBP4TNm1manyS4JLH8Jh3XNJwcrNAFjH16LMTuXuQ/KPfl/rh1uNvXAwad2ivb KpoLpyjH6PWQqZDy1d0TRnx4ctyQL6QCHFcbyoEmqMcizmEdDIdZlmZ+NiiWJ7JCxIS94R l2uyQyJUucyrnL6EdifGCP1bPmeBG2I= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 094C24086B; Thu, 27 Aug 2026 16:32:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 344981F000E9; Thu, 27 Aug 2026 16:32:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787848363; bh=O2H9pqs8u34SiJIXHKDFq+rwx9sPKmCRJst1ewdjsNw=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=nIcGb32mQfEr6c/fcEN/unuJaN/W+Qai8SWc+gqmzERucF4JQcZxBJAy6tDJ5kwZE 9Ni44t4HJbM0K5MQwkd1989ITcJMutInWJLazhW1TRGQatqyvS+9KoSkD/RxEWhVtQ 7HkqFznudh4UyftRHSxasaensi8nlbc6+8qPGQpqNu5brWObfQ0/hLADkZNOYh5+Vo 0Vo//IkWKNxX8asFOMxmzccBa93DGq8g82aaGExia98Nc0pIBe2l+tZczq4h+zn5dF hk05oD0xVv0KoAdlBHsN8MypXoClZj7LPfiZCwlQVo6x6tlmiwNgODgYrso5oHxzzK z+mJOE49ynIuQ== Message-ID: Date: Thu, 27 Aug 2026 18:32:36 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 08/18] mm/huge_memory: move unmap and remap into the split helpers To: kasong@tencent.com, linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Andrew Morton , Lorenzo Stoakes , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Lance Yang , Usama Arif , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Chris Li , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Youngjun Park , Shivam Kalra , Kairui Song References: <20260821-swap-thp-cleanup-v3-0-9b43f5163238@tencent.com> <20260821-swap-thp-cleanup-v3-8-9b43f5163238@tencent.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20260821-swap-thp-cleanup-v3-8-9b43f5163238@tencent.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: B598340006 X-Stat-Signature: 9eatbkopzx6opk7o5fdicqoru4ax5xgt X-HE-Tag: 1787848365-418609 X-HE-Meta: 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 nMHaOXxY wrloJ9JJbsJ11RhuQPsZbVh2yM/C43PgobVhE2hl3sdhwYLbZJneW8AVBBrW3UYxuOiklQQNIzWAaFRye2/3egw/Wuxm1eH2Ds6PMAcuXfh4usPhNHgW1W3fpCEGUZoyBiUdnTRUQcJtleZO7l3UTHUdCN+6klwPCBhO1wZDrpq4kSmmQtQYULK+GWG57LBagMi0KjxhxuqReimScVJK0/D6tDjSlk/+5ge/wJ0vkdnh/gS0VSWZiIZXxxgnVtNg+QbJAqGRtzaarzcbL4TL/ddU17CIZl6KWXpmRiPUC6jS6W0bkmyU3Kx+0hEI1eTlJKRqErDgjJeujp0VgVN0YC5SnuNZrX9L7Q+oh Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 8/20/26 20:55, Kairui Song via B4 Relay wrote: > From: Kairui Song > > To prepare for further cleanup, move the unmap/remap handling from > __folio_split() into the split helpers. Only anon folios need to > be remapped, so remap_page() is now only called for anon splits and > the anon check in remap_page() is redundant and can be removed. I can understand why we would want to move the remap_page(). But why the unmap_folio()? > > Reviewed-by: Zi Yan > Signed-off-by: Kairui Song > --- > mm/huge_memory.c | 58 ++++++++++++++++++++++++++++++-------------------------- > 1 file changed, 31 insertions(+), 27 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 01c8cf428595..af9c2edd1fba 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -3589,9 +3589,6 @@ static void remap_page(struct folio *folio, unsigned long nr, int flags) > { > int i = 0; > > - /* If unmap_folio() uses try_to_migrate() on file, remove this check */ > - if (!folio_test_anon(folio)) > - return; > for (;;) { > remove_migration_ptes(folio, folio, TTU_RMAP_LOCKED | flags); > i += folio_nr_pages(folio); I think we should rename that function now to unmap_folio, but likely better unmap_anon_folio(). > @@ -3933,19 +3930,23 @@ static unsigned int folio_cache_ref_count(const struct folio *folio) > return folio_nr_pages(folio); > } > > -static int __folio_freeze_split_unmapped_anon(struct folio *folio, unsigned int new_order, > - struct page *split_at, bool do_lru, > - struct list_head *list, enum split_type split_type) > +static int __folio_split_unmap_and_freeze_anon(struct folio *folio, unsigned int new_order, > + struct page *split_at, bool do_lru, bool unmap, > + struct list_head *list, enum split_type split_type) > { > struct folio *end_folio = folio_next(folio); > struct swap_cluster_info *ci = NULL; > struct folio *new_folio, *next; > int old_order = folio_order(folio); > + enum ttu_flags ttu_flags = 0; > struct list_lru_one *lru; > struct lruvec *lruvec; > bool dequeue_deferred; > int ret = 0; > > + if (unmap) > + unmap_folio(folio); I really hate that "bool unmap" parameter. folio_split_unmapped() has this VM_WARN_ON_ONCE_FOLIO(folio_mapped(folio), folio); So you can really just do if (folio_mapped()) unmap_folio(folio); Or have an early exit and hide it in unmap_folio(). -- Cheers, David