From nobody Sun Feb 8 17:43:45 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 E38EBEB64DC for ; Thu, 20 Jul 2023 11:30:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231345AbjGTLaM (ORCPT ); Thu, 20 Jul 2023 07:30:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231338AbjGTLaL (ORCPT ); Thu, 20 Jul 2023 07:30:11 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 816F4B7 for ; Thu, 20 Jul 2023 04:30:10 -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 8F7172F4; Thu, 20 Jul 2023 04:30:53 -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 AD2953F6C4; Thu, 20 Jul 2023 04:30:08 -0700 (PDT) From: Ryan Roberts To: Andrew Morton , Matthew Wilcox , Yin Fengwei , David Hildenbrand , Yu Zhao , Yang Shi , "Huang, Ying" , Zi Yan Cc: Ryan Roberts , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v3 1/3] mm: Allow deferred splitting of arbitrary large anon folios Date: Thu, 20 Jul 2023 12:29:53 +0100 Message-Id: <20230720112955.643283-2-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230720112955.643283-1-ryan.roberts@arm.com> References: <20230720112955.643283-1-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