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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=ham 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 82B1FC072B5 for ; Fri, 24 May 2019 16:11:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 58C252133D for ; Fri, 24 May 2019 16:11:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="VdgAfLUX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390822AbfEXQLu (ORCPT ); Fri, 24 May 2019 12:11:50 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:35060 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390411AbfEXQLu (ORCPT ); Fri, 24 May 2019 12:11:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=XMpCB89ytjbHczxqQZJ1ZkGk4p/wzfOhXhEuznTtcMU=; b=VdgAfLUXLCJlXG5l/7G3EXePj SSJwDOnYPi2jv9q8sjeH/rp5wl1hTE0k/mlDMPdly9vpf0znyQWHE8P/xVkTzmwchhL3NdHUR7Zut n0dGIxrqop8fek0MoEG+PplDVqzElFrd1g2zn+17UZgMLiGSfdYN5pHxWDRasOM76wm59MNcuHm3e W+jzXozQbR427BFuT7WuqXHdnjX8+XTo6y+4gsoqt+cCg+b1HDipQVf4KCcyy1Fnn8fUmaDw9HUBS 80J/IN9BUnKAmEqEy0gKcjABkN60UlsvYuSKfiBxJEEcLE4HITTrK43TTI0zj2SL340n2TrIdrYna rs1KInx3w==; Received: from willy by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1hUCnK-00037T-RC; Fri, 24 May 2019 16:11:46 +0000 Date: Fri, 24 May 2019 09:11:46 -0700 From: Matthew Wilcox To: Johannes Weiner Cc: Shakeel Butt , Andrew Morton , Linux MM , linux-fsdevel , LKML , Kernel Team Subject: Re: xarray breaks thrashing detection and cgroup isolation Message-ID: <20190524161146.GC1075@bombadil.infradead.org> References: <20190523174349.GA10939@cmpxchg.org> <20190523183713.GA14517@bombadil.infradead.org> <20190523190032.GA7873@bombadil.infradead.org> <20190523192117.GA5723@cmpxchg.org> <20190523194130.GA4598@bombadil.infradead.org> <20190523195933.GA6404@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190523195933.GA6404@cmpxchg.org> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 23, 2019 at 03:59:33PM -0400, Johannes Weiner wrote: > My point is that we cannot have random drivers' internal data > structures charge to and pin cgroups indefinitely just because they > happen to do the modprobing or otherwise interact with the driver. > > It makes no sense in terms of performance or cgroup semantics. But according to Roman, you already have that problem with the page cache. https://lore.kernel.org/linux-mm/20190522222254.GA5700@castle/T/ So this argument doesn't make sense to me.