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 X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FD66C2BD09 for ; Wed, 4 Dec 2019 15:32:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5A6702081B for ; Wed, 4 Dec 2019 15:32:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575473550; bh=e517Yg9aumVhsxOa0qUbC+kXGIaj1ydlq4wSKgUoxpQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=P1K7Kk4ffU1tn0DH9LHQ1lSnFX6gQwf4gxfoWiinZhwBGTql4iro/4iw3gSW6VN23 uva+904+TZ5vwq9YYgtbQctcAkNqtsep5Md8tlBl0zEMUPBiAXMeQFV35XynK1rW6p 12y9CFDdSSqQGG5HnKDK0rgn9v4RtYRP+eAKVlF0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728413AbfLDPc3 (ORCPT ); Wed, 4 Dec 2019 10:32:29 -0500 Received: from mail-wm1-f68.google.com ([209.85.128.68]:51481 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728296AbfLDPc3 (ORCPT ); Wed, 4 Dec 2019 10:32:29 -0500 Received: by mail-wm1-f68.google.com with SMTP id g206so162283wme.1 for ; Wed, 04 Dec 2019 07:32:27 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=fqpdfGJVxXCTd1ysYnxGhEaU7ov9/g/+UiQFsLmwatE=; b=H0UvgD27x0mH7eA+xDS2DPfoV384onhiB1GvAKxBYknCfyhmQwily4z9W9BFLkQjlz qDePjavJshCAdnxMB+XI7jCJljzRiyCX5kMrNENum7ke8mspj8Kk86cZAvKb3YUN+1d0 RK0240GQPBgbcc9ndb6TTkAAk7tUFDuRdGp3LLiFpqRx8gXowWCcvOF7nnNcWlJmK8Ak YpldZe9VmJZaAkJ2I4P3N3hvz6yUqHI24RciBHQzlnp9pQp+TAkqXvcouTi2v9H4n6o0 IJ4tvhanNHgLDSTLwWcDKrkH3Kxl2aiDFgarEAyo+CVF45q0/1av9tCV7jir7Cx4cjqB 58fg== X-Gm-Message-State: APjAAAUFBQfbEMyTG+zoJnUejIxOw9Qs6zuXfv5nGTFe8WxA58UlJuXA DIRFjaWd0clWru7cYXrPff6QmRv9 X-Google-Smtp-Source: APXvYqwn/WBB/hzGKanp+10p5bs6mE9YPi314bhT+wgpY0uHtHl9inmjfYZyNG1dLol7J+sZ06AyBg== X-Received: by 2002:a7b:c7cc:: with SMTP id z12mr140509wmk.115.1575473546961; Wed, 04 Dec 2019 07:32:26 -0800 (PST) Received: from localhost (prg-ext-pat.suse.com. [213.151.95.130]) by smtp.gmail.com with ESMTPSA id n12sm7280468wmd.1.2019.12.04.07.32.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 Dec 2019 07:32:25 -0800 (PST) Date: Wed, 4 Dec 2019 16:32:25 +0100 From: Michal Hocko To: Christopher Lameter Cc: LKML , linux-mm@kvack.org Subject: Re: SLUB: purpose of sysfs events on cache creation/removal Message-ID: <20191204153225.GM25242@dhcp22.suse.cz> References: <20191126121901.GE20912@dhcp22.suse.cz> <20191126165420.GL20912@dhcp22.suse.cz> <20191127162400.GT20912@dhcp22.suse.cz> <20191127174317.GD26807@dhcp22.suse.cz> <20191204132812.GF25242@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 04-12-19 15:25:43, Cristopher Lameter wrote: > On Wed, 4 Dec 2019, Michal Hocko wrote: > > > > > Just drop the events may be best. Then we know if someone is using it. > > > > > > I would be worried that a lack of events might be surprising and a > > > potential userspace wouldn't know that something has changed. > > > > It would be great to land with some decision here. > > Drop the events. These are internal kernel structures and supporting > notifiers to userspace is a bit unusual. As I've said I believe it is quite risky. But if you as a maintainer believe this is the right thing to do I will not object. Care to send a patch? -- Michal Hocko SUSE Labs