Received: by 2002:a25:7ec1:0:0:0:0:0 with SMTP id z184csp4414354ybc; Tue, 26 Nov 2019 08:34:39 -0800 (PST) X-Google-Smtp-Source: APXvYqzBejFFVjuMNFa96WO+XtTzUMC9iLQHHrgRNpQ+V4tC9oTBjGxaHD+V9vFuUM6qwACIUjFN X-Received: by 2002:a17:907:11cc:: with SMTP id va12mr24369122ejb.164.1574786079158; Tue, 26 Nov 2019 08:34:39 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1574786079; cv=none; d=google.com; s=arc-20160816; b=fsYH0VkynxZkSqIuxLYDV7rG/eHoMwTKsPuXVEZFnu8x2mH3+kYbBw7y97bkCPrNA6 HL3iUr6+n9bHp/3SytFIEdWxIZdL7ZAO+B89O3IAuCK6sp2nJsbLv0KEQag/G4ZO1N/J kXmAWH8gQIZNb48TWV3lsGIOOU7QONlsFgm7UwvpyKjfQMBiss0xsGhSWBKKu8jFIur+ Erw5m2S4EP8xYracE08rlswShh8CKhdeMOujswGGvCD0u4O1j5dIj53BYxQG9mRs40Vf 0vGpb/42MaYw4ydeJwtVwDPQMxN3KWVtC8+JSh1x2xXY5hBWd6rTi6gP8rlRvz8iwcP1 hOIQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:mime-version:user-agent:references :message-id:in-reply-to:subject:cc:to:from:date; bh=woCmHd1mQDwC6Bx5XMlySAcl4EmCi1f5Y832VuO909s=; b=MBt5usQ8HHnSg6dUj21I9Iz41/F5C17wu2OY4PO1/4e9UizEGCAkVWkXCwHsbjgXaf OOcOK6CJFg8WdVuHRdkzNezs4CUfrkGSrFy6+BuxT8g9mKBhKLOSd73EJouq97e2uKOt /1ODVJJyp/w41HJBf7E3AF0PV1uZcVzrI4jyb4v8Gav780HSnmQmDtEBd2tohsLd5zFu ivnbiQoRa+5eE2qTa1p35cGqoGYJOH6Rjz8zu4+B3B0opZWbxRHw/j4VgrZsXYJCOO78 zeiyqFDybvLolSjIEth8QOjRycedzWWxWp2V42jl33lg5XtXe9v6ek1Z1T/sMwPUz40k uxxw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id e19si7289724ejb.379.2019.11.26.08.34.13; Tue, 26 Nov 2019 08:34:39 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727532AbfKZQc5 (ORCPT + 99 others); Tue, 26 Nov 2019 11:32:57 -0500 Received: from gentwo.org ([3.19.106.255]:39390 "EHLO gentwo.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725972AbfKZQc4 (ORCPT ); Tue, 26 Nov 2019 11:32:56 -0500 Received: by gentwo.org (Postfix, from userid 1002) id 1F2FE3ED43; Tue, 26 Nov 2019 16:32:56 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by gentwo.org (Postfix) with ESMTP id 1E4D83EC49; Tue, 26 Nov 2019 16:32:56 +0000 (UTC) Date: Tue, 26 Nov 2019 16:32:56 +0000 (UTC) From: Christopher Lameter X-X-Sender: cl@www.lameter.com To: Michal Hocko cc: LKML , linux-mm@kvack.org Subject: Re: SLUB: purpose of sysfs events on cache creation/removal In-Reply-To: <20191126121901.GE20912@dhcp22.suse.cz> Message-ID: References: <20191126121901.GE20912@dhcp22.suse.cz> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 26 Nov 2019, Michal Hocko wrote: > Hi, > I have just learnt about KOBJ_{ADD,REMOVE} sysfs events triggered on > kmem cache creation/removal when SLUB is configured. This functionality > goes all the way down to initial SLUB merge. I do not see any references > in the Documentation explaining what those events are used for and > whether there are any real users. > > Could you shed some more light into this? I have no idea about what this is. There have been many people who reworked the sysfs support and this has been the cause for a lot of breakage over the years.