From nobody Wed Feb 11 06:30:44 2026 Received: from out30-130.freemail.mail.aliyun.com (out30-130.freemail.mail.aliyun.com [115.124.30.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1C63D1AC431 for ; Thu, 4 Jul 2024 11:25:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.130 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720092320; cv=none; b=NCpBlIZbglRlxFlk1zR9jTBpShtZGrQqwEz9D+OuovnHaAnxQZYfcPn9NCD7Dpp7cVNiwfganeVC0Rc7+Ef3YXlhBStGYJxpMyMLHS5+BUUdzZ6lPPZpt3RtwwV3oZRWi2enTZ0ySTKaKs6lpWqD1hRQIEKPXLOpOlMsMR1gMwU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720092320; c=relaxed/simple; bh=0GBn0WLyFfTnZqZxayQz4y6BfCnwGmOo7URL0mMJmc0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=sVImzuginn9FUTYfig30O6Bb8kdA2Hz7XNLx56fJQn8jNucAuk0xnrRXT2B9tr3EoH32P/iRKH81S0TRO2/+uj24xFi2TzYDu3OqMYbybCwoMhC5RKxDw3gt1GZXYN50RICQpWtH+eKexze3QkVceLAUlItcPam2rH9ILHzrMMo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=CCjZi0lw; arc=none smtp.client-ip=115.124.30.130 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="CCjZi0lw" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1720092310; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=gnvmYA2eSyc6bAhukdfnEGSceMWwrl4WSlzxAF32JnQ=; b=CCjZi0lwY1mBkJrU6DuNIHswHSZEFu4DHKb/DV0/RuSchNRaWG5l2SrRhysnnqxWYPd4dncEA/fbYd5qcnbjRiago2UKZoYWipTFV4OeDa4y6EnVVWrtad7gxEnbA9/erDJYqLcI6MDy3o2DxpJ22tpByE0k9vonKgDxZY1Ipno= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R101e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033037067110;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=17;SR=0;TI=SMTPD_---0W9qjOw7_1720092308; Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0W9qjOw7_1720092308) by smtp.aliyun-inc.com; Thu, 04 Jul 2024 19:25:08 +0800 From: Baolin Wang To: akpm@linux-foundation.org, hughd@google.com Cc: willy@infradead.org, david@redhat.com, wangkefeng.wang@huawei.com, chrisl@kernel.org, ying.huang@intel.com, 21cnbao@gmail.com, ryan.roberts@arm.com, shy828301@gmail.com, ziy@nvidia.com, ioworker0@gmail.com, da.gomez@samsung.com, p.raghav@samsung.com, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 01/10] mm: vmscan: add validation before spliting shmem large folio Date: Thu, 4 Jul 2024 19:24:50 +0800 Message-Id: X-Mailer: git-send-email 2.39.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Page reclaim will not scan anon LRU if no swap space, however MADV_PAGEOUT can still split shmem large folios even without a swap device. Thus add swap available space validation before spliting shmem large folio to avoid redundant split. Signed-off-by: Baolin Wang --- mm/vmscan.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/mm/vmscan.c b/mm/vmscan.c index 1807e5d95dda..61465f92283f 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1237,6 +1237,14 @@ static unsigned int shrink_folio_list(struct list_he= ad *folio_list, } } else if (folio_test_swapbacked(folio) && folio_test_large(folio)) { + + /* + * Do not split shmem folio if no swap memory + * available. + */ + if (!total_swap_pages) + goto activate_locked; + /* Split shmem folio */ if (split_folio_to_list(folio, folio_list)) goto keep_locked; --=20 2.39.3