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 3CEF4D47CD6 for ; Fri, 16 Jan 2026 10:52:37 +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=RTCekCAuKETvEuN9jTbDLB1P7rv4peQ92+oXwOTcp18=; b=u7op/34vge1YJuzjcmt7laNCV9 J6jDaxyWMFuG28toMz/zYDp1HFIGhNpMPIjPLdPLvB+YJ3JZN3yfed81GSc+xrDge85/pCzMFCo/Z B/mjOouH6ZdzfYlNSZO0lMUyu9LII8sokS9mrLJqCshMTGmVaNWkqpJr4qRgCs/7HZRvm3NmkE63L QQHNulL0acUE//f9C6GRk0Om46EQNk+E9yMMSdjvDZv2NDaH1A+AE/7fEA2BeU1YUkLu+dwlvDoLU g8AeLiIE2P5Rwlj17PFbR7JG7QMAaWFlA2qv8dxxRWM2vvx8a61xPbBVWVLAw4+Bh71T9jRwlxAFA zwaj9qyQ==; 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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: > 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 Arm 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). > > Similar to folio_referenced_one(), we can also apply batched unmapping for large > file folios to optimize the performance of file folio reclamation. By supporting > batched checking of the young flags, flushing TLB entries, and unmapping, I can > observed a significant performance improvements in my performance tests for file > folios reclamation. Please check the performance data in the commit message of > each patch. > > Run stress-ng and mm selftests, no issues were found. Baolin, I'm intending to review this, but it might still take me a bit until I get to it. (PTO/vacation and other fun) -- Cheers David