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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3241DF45A12 for ; Sat, 11 Apr 2026 00:34:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 91B116B0089; Fri, 10 Apr 2026 20:34:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8CB606B008A; Fri, 10 Apr 2026 20:34:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7B9D46B0092; Fri, 10 Apr 2026 20:34:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 661D56B0089 for ; Fri, 10 Apr 2026 20:34:32 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 1530B160671 for ; Sat, 11 Apr 2026 00:34:32 +0000 (UTC) X-FDA: 84644403984.10.4813A78 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf10.hostedemail.com (Postfix) with ESMTP id 16A44C000D for ; Sat, 11 Apr 2026 00:34:29 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=XZJ2Bd8q; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of baohua@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=baohua@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1775867670; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=xIEz4rF1j8JpIYdjyvbkQ+33mKAMpyIpO5NlOVfqQRU=; b=dxQKZuAwpCRoR5pjGh2vNO4/Rio+iwgsgCBXARPVoKmZ1HKLnycCIHimS9gxxNkePgfFP7 nTZPMFUUJNV7a36UAhdnZFBDDUDzE84BkMXdJT8G5WodqOUe2KFO8Kps/qNxHKUGbRsU5Y 6vm/pCjSEGidvMJ9v+fDvrsyMCQnHXQ= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1775867670; a=rsa-sha256; cv=none; b=cJV1q3rUIxjMAnNUi2HNslrs0Opp4uvWCH2TQGRjhAIDV8iVjD9grx0lW5jmhsADp8r1ov JUXRni8+bCIV4Jn0CKrKWlxf0aouXXWvScK7LfwAzOVnAiIEyJhQ7fCyc7Daft0UaJH78z +PQ/cI5IDh89vTeAXT4VbTvEpSAhkvo= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=XZJ2Bd8q; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of baohua@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=baohua@kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id BE5424455F for ; Sat, 11 Apr 2026 00:34:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D6BAC2BCB9 for ; Sat, 11 Apr 2026 00:34:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775867668; bh=aMaxyM9DAkGN7TpTqVyxxpJ5lbyTiW9bNKnlaUTAsTs=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=XZJ2Bd8qPVI/y4dtDVyzxHXr4b74Krm2kIeqXFmeYQ0x9f+MDyPYrhhvX/rxuedkd P0s7bR97+bmq/SY6BLSikkAJVcKnbm+W0wc0qm6LvLXLBZtpwvAs+J6+w5BFoSvY8U /cfBc2KBEQqt6ECghoA88vEsJuzvvUbuzz1mrao1LVVBSvoMzMX4I71fqmCGx3UnKO 2vOybVglzMIRNrBFmJh5TcpLFc0GTGSvrMfWg/dN855HPiFm1DElKhr9GSOJt3UCRa dMHLV9rIxQ9CpHsaXJXBZ/Cf5EMAAfNhM2r1ZpbAVEbdxk6nuORGCQ88VOg0gzRHDc fuozjg0AIk6Ug== Received: by mail-qk1-f176.google.com with SMTP id af79cd13be357-8d68f702851so415173185a.0 for ; Fri, 10 Apr 2026 17:34:28 -0700 (PDT) X-Forwarded-Encrypted: i=1; AJvYcCXXPcynstxGALbeoABUOqj/fBwwfoJTWYS9rh50eHyB+zspxIDIXyczKLNikmeP0XiSCHG7gu3JkA==@kvack.org X-Gm-Message-State: AOJu0YyWTSavz8TWOm3cHqppxKAzslx5SjcD/HmyRvgxMsACKV0FCUBM T7EXnYU0B6f9OimfDBt7nJTYGl0kKAAUtId07RJW9BxNcUgtDMgtalOZXM1Uko/KqAimGzuBPx+ 8Jzm8OdOUyF3WIrStYin8d7IMeW1hDjs= X-Received: by 2002:a05:620a:4688:b0:8da:dc5d:acf5 with SMTP id af79cd13be357-8ddcd022c95mr752874885a.12.1775867667820; Fri, 10 Apr 2026 17:34:27 -0700 (PDT) MIME-Version: 1.0 References: <20260410-batch-tlb-flush-v3-0-ff0b9d3a351a@icloud.com> <20260410-batch-tlb-flush-v3-5-ff0b9d3a351a@icloud.com> In-Reply-To: <20260410-batch-tlb-flush-v3-5-ff0b9d3a351a@icloud.com> From: Barry Song Date: Sat, 11 Apr 2026 08:34:16 +0800 X-Gmail-Original-Message-ID: X-Gm-Features: AQROBzC5fBeIxMPrjkqKy2brcpvcoT6Fd58zwoWklkcj-YVyph3-AAt7Y71TUu0 Message-ID: Subject: Re: [PATCH v3 5/5] mm/vmscan: flush TLB for every 31 folios evictions To: Zhang Peng Cc: Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Johannes Weiner , Qi Zheng , Shakeel Butt , Axel Rasmussen , Yuanchu Xie , Wei Xu , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Kairui Song , Zhang Peng Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 16A44C000D X-Stat-Signature: fe44j51ew391aqqocruojyurtwomfd3p X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1775867669-534836 X-HE-Meta: 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 YEjxQFIa GhX8S/v+isWwc6/TfGvrBv23QrXAmzvynZiG+CPCXeUNtR51kgGBaBeHHUSFfbautxzeTQQoA48DuWmm0KBVsWfC5hjgAkUYuerpyokJpLL5Go1wCbMo3WWO7bIFPSkRDYxX9YN6o6I/CjIo2y91Pr7p1/EzmdyRR0YSq+oNu3gmB2W+qB0JgA5+gtx64sVxgFyoOyESco3FdidrSpyo49dh5HyaEPy/7NdVHHFHQX9FaK2z9NZe7DFxjHT+YTFB25XjuK0T9GeLi93nRQFAHhC1iEGIIfErroRnDFW91DkStTOLHNfkvzZ52ajM8jQvCIh9xG6b5FSMsoqE= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Apr 10, 2026 at 8:48=E2=80=AFPM Zhang Peng wrote: > > From: Zhang Peng > > Currently we flush TLB for every dirty folio, which is a bottleneck for > systems with many cores as this causes heavy IPI usage. > > So instead, batch the folios, and flush once for every 31 folios (one > folio_batch). These folios will be held in a folio_batch releasing their > lock, then when folio_batch is full, do following steps: > > - For each folio: lock - check still evictable (writeback, mapped, > dma_pinned) > - If no longer evictable, put back to LRU > - Flush TLB once for the batch > - Pageout the folios > > Suggested-by: Kairui Song > Signed-off-by: Zhang Peng This sounds like a pretty good idea, but let=E2=80=99s revisit it after you clean up 1=E2=80=934. Best Regards Barry