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 29AF5E7E0B2 for ; Mon, 9 Feb 2026 09:38:21 +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: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=YKvwJvBXtLVQGPrmklEbw6SP6/SMJNsk0MFQ+sb5+Wk=; b=zqAAV0hl+PVtBZtfAtBYocsB3i NWhtc5FyyNNLw1jo3bW6lVwR5tK42/h46O00yDC5GsBVfD242T65buAPkZhThCJWYL1GFEjH+uitC qymC9JucVZevEgFVLqIMrb1iyx7HiXRD3siXzoQHmfJszv7WLwVs+lv1k/UfffXugpPaKyPtMee0l velo10SrstM6O6mytvgcUEoGVFL8iDrwqfG2i9z1N5JameqjRzbhk4lteDvPx9GIQtm1yNxK4/wvr hrzjjgOfIWsIWdHdhjR8y/Q+ZGkdC6kWlPEPfnxMgoQznpPrdGQINpe+UmWLLz+Ve7xfspjjkJV6K bMoSJF4A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vpNih-0000000F9fg-0Xod; Mon, 09 Feb 2026 09:38:15 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vpNif-0000000F9fQ-2yNa for linux-arm-kernel@lists.infradead.org; Mon, 09 Feb 2026 09:38:13 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id A9A64600C4; Mon, 9 Feb 2026 09:38:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2B294C116C6; Mon, 9 Feb 2026 09:38:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770629892; bh=v+A4ucgLu6hDabFShguMd9iJICkSkIkwur7q7jqK3yU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=rvD2kJmaNNEMUzuZ+jTcSMADRKAHroxxgx97c/Z4J8dIGeTQmFZ7B0XsQxzw6+IKf +RjyvkuOkCfT4uvDZgqcrXDNVndMSij3rBuNoQpc2s/DN2Qs37lzYSAJ9RGqIBaGDf 5O0BbFoD33p6HVNMnKwX3UYHAIYSzhbrFpEQyhYGiY1V6b+TQ4s46kOJ3qQw42CRxO yXQPXzlWgguPL8i4uB2aSQsU2Ie9NpJi4iKq/rTbwgC40IYbjjkoVn73GTv5DNrI4Y HTX/oYm3h/hfy+74OS5nDIPNqCmiVOjZHF7iKKAuey2sJ0SFmboyAJ9GsKOtpILUOL jCqqAniNZISrw== Message-ID: <46d0b6bf-db7e-418f-a497-983db4d4d786@kernel.org> Date: Mon, 9 Feb 2026 10:38:02 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 5/5] mm: rmap: support batched unmapping for file large folios To: Baolin Wang , akpm@linux-foundation.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, dev.jain@arm.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <142919ac14d3cf70cba370808d85debe089df7b4.1766631066.git.baolin.wang@linux.alibaba.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit 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 On 12/26/25 07:07, Baolin Wang wrote: > Similar to folio_referenced_one(), we can apply batched unmapping for file > large folios to optimize the performance of file folios reclamation. > > Barry previously implemented batched unmapping for lazyfree anonymous large > folios[1] and did not further optimize anonymous large folios or file-backed > large folios at that stage. As for file-backed large folios, the batched > unmapping support is relatively straightforward, as we only need to clear > the consecutive (present) PTE entries for file-backed large folios. > > 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 (and 50%+ improvement > on my X86 machine) with this patch. > > W/o patch: > real 0m1.018s > user 0m0.000s > sys 0m1.018s > > W/ patch: > real 0m0.249s > user 0m0.000s > sys 0m0.249s > > [1] https://lore.kernel.org/all/20250214093015.51024-4-21cnbao@gmail.com/T/#u > Reviewed-by: Ryan Roberts > Acked-by: Barry Song > 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 985ab0b085ba..e1d16003c514 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -1863,9 +1863,10 @@ 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; Right, the anon folio handling would require a bit more work in the } else if (folio_test_anon(folio)) { branch. Do you intend to tackle that one as well? I'll reply to the fixup. -- Cheers, David