From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 97D701A6835; Tue, 8 Sep 2026 16:31:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788885061; cv=none; b=X/T7hGK6xyP8zbDfX0lkeDHg5G1lPXEexjr42sQGySRg82Ux0+fO3+5FNNkmm+bRUO174BqqmirnZeqtte/r/5amLCe0Fr6WemIVtPu8ISMlfuQwJ/n1k+jBQgM6ZWsAXpx71CvWiB0jv5kwgNYVvnbPCl4qB+cR1j831glh1lk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788885061; c=relaxed/simple; bh=5Ec4aSY7o3k0sKM9wWHt9rsFs5lO16AT9ABnU8TGsao=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=nYEF/kspaEt5XuQQHZ/1lNL67sHz2BbEiueTUX8dGhLnNTsIlCqVBNuqz/38ghV9yduUuBQbknmLHQlXTFWyd2oYMokqqqwM25ivL31xTKEYjHaUTK5ohJGj+F9cJsW006NKE7WNfJKVtqWaHjKuXZgszK4xG3wHn9gHvZs03t4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JJhwsDAz; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="JJhwsDAz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 687791F00A3A; Tue, 8 Sep 2026 16:30:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788885060; bh=PbREINwiHzdfOIDyvzXmpqXBcn2ufYLyhPRpYbuszSY=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=JJhwsDAzdDYYBuw+OjApzid/DL+uKEvAJ2ThGvEQEp2/vT/ZgMLMANci4KhIZVs+q KJIDDQQEyY89H+5OdaSGpu84eRh3LwQimAoVYTdEGIr2HH6/9L/SixMgZ/eRkkp52m HbFatySDrHgffwcdSMmR1TKgUfv7D8u8QNU9vBBvQDD5ag/tdudXWiBGWJIgqhyP20 DUX/YejlKToKQSDWX24HIZrv5PvbQhTnV/ykAxojd5wB18HHVIGHuG5DUbmadoVHmP tLQYD8brxV8cRvpS+E2sUT9aaSJuO4XG6dBrT5eWlTQggVrvOdfVg8KQSmvc6cdwZ6 xhu0OCpOAfQuQ== Message-ID: Date: Tue, 8 Sep 2026 18:30:50 +0200 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 03/25] mm/fbatch: temporarily disable lazyfree and mlock+munlock batching Content-Language: en-US To: Hugh Dickins , Andrew Morton Cc: Ackerley Tng , Alexander Viro , Baolin Wang , Barry Song , Binbin Wu , Christian Brauner , Christoph Hellwig , Christoph Lameter , Claudio Imbrenda , David Hildenbrand , JP Kobryn , Jan Kara , Jens Axboe , Johannes Weiner , Kairui Song , Kiryl Shutsemau , Lance Yang , Leonardo Bras , Lorenzo Stoakes , Marcelo Tosatti , Matthew Wilcox , Mel Gorman , Miaohe Lin , Michal Hocko , Minchan Kim , Muchun Song , Oscar Salvador , Peter Zijlstra , Qi Zheng , Rik van Riel , Sebastian Andrzej Siewior , Shakeel Butt , Suren Baghdasaryan , Yang Shi , Yu Zhao , Zach O'Keefe , Zi Yan , linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <14a16945-529b-8bc0-ab38-3ea97e54e223@google.com> <9593975e-8732-999a-73d1-37fd332eb840@google.com> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/24/26 15:58, Hugh Dickins wrote: > It will not matter if we occasionally get activation or deactivation > wrong; but a mistaken lazyfree (MADV_FREE) would likely cause dataloss. > So disable its batching while reworking the per-cpu fbatch handling, > then re-enable it with more thought afterwards. > > Similarly disable mlock+munlock batching temporarily: they will need > some redesign before re-enabling. Just insert one disabling line for > now, leaving the rest of the code as it was, for consideration later. > > Signed-off-by: Hugh Dickins Reviewed-by: Vlastimil Babka (SUSE)