From nobody Mon Feb 9 09:10:22 2026 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 7FD9BC0015E for ; Thu, 27 Jul 2023 14:18:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233594AbjG0OS5 (ORCPT ); Thu, 27 Jul 2023 10:18:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52854 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233509AbjG0OSw (ORCPT ); Thu, 27 Jul 2023 10:18:52 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E59BC122 for ; Thu, 27 Jul 2023 07:18:51 -0700 (PDT) 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 92B98FEC; Thu, 27 Jul 2023 07:19:34 -0700 (PDT) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8D9823F6C4; Thu, 27 Jul 2023 07:18:49 -0700 (PDT) From: Ryan Roberts To: Andrew Morton , Matthew Wilcox , Yin Fengwei , David Hildenbrand , Yu Zhao , Yang Shi , "Huang, Ying" , Zi Yan , Nathan Chancellor , Alexander Gordeev , Gerald Schaefer Cc: Ryan Roberts , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v4 1/3] mm: Allow deferred splitting of arbitrary large anon folios Date: Thu, 27 Jul 2023 15:18:35 +0100 Message-Id: <20230727141837.3386072-2-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230727141837.3386072-1-ryan.roberts@arm.com> References: <20230727141837.3386072-1-ryan.roberts@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" In preparation for the introduction of large folios for anonymous memory, we would like to be able to split them when they have unmapped subpages, in order to free those unused pages under memory pressure. So remove the artificial requirement that the large folio needed to be at least PMD-sized. Reviewed-by: Yu Zhao Reviewed-by: Yin Fengwei Reviewed-by: Matthew Wilcox (Oracle) Reviewed-by: David Hildenbrand Signed-off-by: Ryan Roberts --- mm/rmap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/rmap.c b/mm/rmap.c index 0c0d8857dfce..eb0bb00dae34 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1426,11 +1426,11 @@ void page_remove_rmap(struct page *page, struct vm_= area_struct *vma, __lruvec_stat_mod_folio(folio, idx, -nr); =20 /* - * Queue anon THP for deferred split if at least one + * Queue anon large folio for deferred split if at least one * page of the folio is unmapped and at least one page * is still mapped. */ - if (folio_test_pmd_mappable(folio) && folio_test_anon(folio)) + if (folio_test_large(folio) && folio_test_anon(folio)) if (!compound || nr < nr_pmdmapped) deferred_split_folio(folio); } --=20 2.25.1