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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CB27CD41C02 for ; Thu, 11 Dec 2025 08:17:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=GTUtfG6uYByUGiREez0T2P/sllJfoIOg91OqMSv2QCo=; b=OYvwgfF+saJPzOzvipaV8Dgb67 7C/aDDFsQgs/D0wV6ZYfcj1dZmSJOEYKjCKbDblmKYlLiBZ9ukGByNdmzOWq43F8YHmrlcdafaNwn Gd5ieINqHgSm1Nzax9vl7CZ7XDhCzY3bgTg5zYORuo1oRFX1hJTC7F4W5XG7eu6x4basnBdYOb576 xgxuIPhRvvApM1WiDL7HGIABpNMClU70vELhHYRKhCSYlPCmoE+b68KQTgyYMDbkV/0bE7YuCVe+b +Xs6Nq/wC1V27JrrzZm5pIx+qQS4U168dGouqJcDYApbqTXbtP4nnAzFJ1YBhEuPKVFVJaGeFL4Uk k4K7SDlw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vTbrW-0000000GMzP-3SOT; Thu, 11 Dec 2025 08:17:22 +0000 Received: from out30-124.freemail.mail.aliyun.com ([115.124.30.124]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vTbrT-0000000GMxl-0JsM for linux-arm-kernel@lists.infradead.org; Thu, 11 Dec 2025 08:17:21 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1765441035; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=GTUtfG6uYByUGiREez0T2P/sllJfoIOg91OqMSv2QCo=; b=gJo4993SZkNx01mWQ6MeC3Fw+IYxByVyhZDRR9vJ6k1L9JJzXVA5emuoqZiUBlPCSn3gJfEj+C2dWyT+gJ8tpjboG+vt9A3XfbnMjOdShZYU891+Ib5M9FMIJkqwO4Gs7mupJBRGkPRy/xacdXNsuS4Ul8WvftrsBFKoUEN/w18= Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0WuZjI5S_1765441033 cluster:ay36) by smtp.aliyun-inc.com; Thu, 11 Dec 2025 16:17:14 +0800 From: Baolin Wang To: akpm@linux-foundation.org, david@kernel.org, catalin.marinas@arm.com, will@kernel.org Cc: lorenzo.stoakes@oracle.com, ryan.roberts@arm.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, riel@surriel.com, harry.yoo@oracle.com, jannh@google.com, willy@infradead.org, baohua@kernel.org, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 3/3] mm: rmap: support batched unmapping for file large folios Date: Thu, 11 Dec 2025 16:16:56 +0800 Message-ID: X-Mailer: git-send-email 2.43.7 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251211_001719_708771_3CC4D202 X-CRM114-Status: GOOD ( 11.00 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Similar to folio_referenced_one(), we can apply batched unmapping for file large folios to optimize the performance of file folios reclamation. Performance testing: Allocate 10G clean file-backed folios by mmap() in a memory cgroup, and try to reclaim 8G file-backed folios via the memory.reclaim interface. I can observe 75% performance improvement on my Arm64 32-core server. W/o patch: real 0m1.018s user 0m0.000s sys 0m1.018s W/ patch: real 0m0.249s user 0m0.000s sys 0m0.249s Signed-off-by: Baolin Wang --- mm/rmap.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/mm/rmap.c b/mm/rmap.c index ec232165c47d..4c9d5777c8da 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1855,9 +1855,10 @@ static inline unsigned int folio_unmap_pte_batch(struct folio *folio, end_addr = pmd_addr_end(addr, vma->vm_end); max_nr = (end_addr - addr) >> PAGE_SHIFT; - /* We only support lazyfree batching for now ... */ - if (!folio_test_anon(folio) || folio_test_swapbacked(folio)) + /* We only support lazyfree or file folios batching for now ... */ + if (folio_test_anon(folio) && folio_test_swapbacked(folio)) return 1; + if (pte_unused(pte)) return 1; @@ -2223,7 +2224,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, * * See Documentation/mm/mmu_notifier.rst */ - dec_mm_counter(mm, mm_counter_file(folio)); + add_mm_counter(mm, mm_counter_file(folio), -nr_pages); } discard: if (unlikely(folio_test_hugetlb(folio))) { -- 2.47.3