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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 51CA4C2BB1D for ; Tue, 14 Apr 2020 06:44:47 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2F40020735 for ; Tue, 14 Apr 2020 06:44:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2F40020735 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 06EDF8637D; Tue, 14 Apr 2020 06:44:47 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 93BmX2LLkCtD; Tue, 14 Apr 2020 06:44:46 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by whitealder.osuosl.org (Postfix) with ESMTP id 65AF5862C7; Tue, 14 Apr 2020 06:44:46 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 5B71FC1D7D; Tue, 14 Apr 2020 06:44:46 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 81880C0172 for ; Tue, 14 Apr 2020 06:44:44 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 656D720027 for ; Tue, 14 Apr 2020 06:44:44 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id y1vRjtaD6HoI for ; Tue, 14 Apr 2020 06:44:43 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by silver.osuosl.org (Postfix) with ESMTPS id BD0D31FEED for ; Tue, 14 Apr 2020 06:44:43 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id C623E68BEB; Tue, 14 Apr 2020 08:44:41 +0200 (CEST) Date: Tue, 14 Apr 2020 08:44:41 +0200 From: Christoph Hellwig To: David Rientjes Subject: Re: [rfc v2 3/6] dma-pool: dynamically expanding atomic pools Message-ID: <20200414064441.GC23359@lst.de> References: <20200410145520.17864-1-hdanton@sina.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Cc: Tom Lendacky , Hillf Danton , "Singh, Brijesh" , "Grimm, Jon" , linux , iommu , Christoph Hellwig X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Fri, Apr 10, 2020 at 12:37:20PM -0700, David Rientjes wrote: > I'll rely on Christoph to determine whether it makes sense to add some > periodic scavening of the atomic pools, whether that's needed for this to > be merged, or wheter we should enforce some maximum pool size. I don't really see the point. In fact the only part of the series I feel uneasy about is the growing of the pools, because it already adds a fair amount of complexity that we might not need for simple things, but shrinking really doesn't make any sense. So I'm tempted to not ever support shrinking, and even make growing optional code under a new config variable. We'll also need a way to query the current size through e.g. a debugfs file. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu