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 5F3A5E81BD9 for ; Mon, 9 Feb 2026 15:25:54 +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=n4BzZkV7IZSA/6cO1gcoL8pcmNo5X2EanQn/RYhI+DQ=; b=OY0gbDMWhMpRJIlnp3onQ40GI6 OP+FSnPIsY53rktuULkBFK/LZESPjqayD9sqgBDqg4MpChbfJsOigeEcpqKts1m5K5lHcCJVvRvUh x6WhA5gMqulrZUfOtIdPv9GEM8p4dYSNXBa1UpKEmOyPMFZy5WS9katMi/VqRUasDCeAjqfyVM/5V 5zf5tsXUqqCclBqgfUD16qAyv4kF29VzdxMLUz1+7JdCvUSm97OS74yaaD/oUgFkbOT03OhXYI3QR Yqr9A0AB/X7EtSWrubZzdKt+yGjIgVV0S50fFt5oZzzu/p8+CNTpc6EhmAUrWzxPPOMXKz8yFw8x8 5VDJ++GA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vpT91-0000000FbbL-45u2; Mon, 09 Feb 2026 15:25:48 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vpT90-0000000FbbE-2xWx for linux-arm-kernel@lists.infradead.org; Mon, 09 Feb 2026 15:25:46 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id B294060131; Mon, 9 Feb 2026 15:25:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 67204C116C6; Mon, 9 Feb 2026 15:25:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770650745; bh=ma+Qb27JkLU5+aWKRXV2EHzborEgIJHMgEqcWWa8W+A=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=seVIAz06FJ4S6JCLyie8xRn+U8cb0dC+kvxkBKZDdPdmuqerI9dlxrz9Fc73Lv9Iy ypwt9GfXGNmyLwO9XLvJvY6Yn6UM097mtI9XnJr70d0JWSHAuzqpePRqx8KvUonc4Z y9D6agHrhE0R4idt7VcL/E1JrZRuYb/shzlXsIK2IS+YGWaAE8FGU7gy5b9Jlu3ViD aFTIJ6m0Irb9C1p2tJrQNQsOkbOHr3EoXKjYX+koGcUcQlWcSWs6WYgDav03DyVZqD GZWjEY3lDVkOoBihyTt9zn3KfA51m4LczeE0W4M8YAMgZzU04Wzavb0jMoj6lBzwkW 7TviaigilWwlw== Message-ID: <81cc2fb0-f6a6-45af-9463-c5138f742455@kernel.org> Date: Mon, 9 Feb 2026 16:25:35 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 1/5] mm: rmap: support batched checks of the references for 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: <12132694536834262062d1fb304f8f8a064b6750.1770645603.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 2/9/26 15:07, Baolin Wang wrote: > Currently, folio_referenced_one() always checks the young flag for each PTE > sequentially, which is inefficient for large folios. This inefficiency is > especially noticeable when reclaiming clean file-backed large folios, where > folio_referenced() is observed as a significant performance hotspot. > > Moreover, on Arm64 architecture, which supports contiguous PTEs, there is already > an optimization to clear the young flags for PTEs within a contiguous range. > However, this is not sufficient. We can extend this to perform batched operations > for the entire large folio (which might exceed the contiguous range: CONT_PTE_SIZE). > > Introduce a new API: clear_flush_young_ptes() to facilitate batched checking > of the young flags and flushing TLB entries, thereby improving performance > during large folio reclamation. And it will be overridden by the architecture > that implements a more efficient batch operation in the following patches. > > While we are at it, rename ptep_clear_flush_young_notify() to > clear_flush_young_ptes_notify() to indicate that this is a batch operation. > > Reviewed-by: Harry Yoo > Reviewed-by: Ryan Roberts > Signed-off-by: Baolin Wang > --- Thanks! Acked-by: David Hildenbrand (Arm) -- Cheers, David