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=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C249AC433DB for ; Wed, 24 Mar 2021 08:43:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 911A0619D3 for ; Wed, 24 Mar 2021 08:43:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234257AbhCXInR (ORCPT ); Wed, 24 Mar 2021 04:43:17 -0400 Received: from verein.lst.de ([213.95.11.211]:36021 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231202AbhCXImy (ORCPT ); Wed, 24 Mar 2021 04:42:54 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id C8A8B68B05; Wed, 24 Mar 2021 09:42:50 +0100 (CET) Date: Wed, 24 Mar 2021 09:42:50 +0100 From: Christoph Hellwig To: Florian Fainelli Cc: linux-kernel@vger.kernel.org, Konrad Rzeszutek Wilk , Christoph Hellwig , Marek Szyprowski , Robin Murphy , "open list:SWIOTLB SUBSYSTEM" Subject: Re: [PATCH v3] swiotlb: Make SWIOTLB_NO_FORCE perform no allocation Message-ID: <20210324084250.GA4474@lst.de> References: <20210321033740.312500-1-f.fainelli@gmail.com> <20210323015350.399493-1-f.fainelli@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210323015350.399493-1-f.fainelli@gmail.com> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 22, 2021 at 06:53:49PM -0700, Florian Fainelli wrote: > When SWIOTLB_NO_FORCE is used, there should really be no allocations of > default_nslabs to occur since we are not going to use those slabs. If a > platform was somehow setting swiotlb_no_force and a later call to > swiotlb_init() was to be made we would still be proceeding with > allocating the default SWIOTLB size (64MB), whereas if swiotlb=noforce > was set on the kernel command line we would have only allocated 2KB. > > This would be inconsistent and the point of initializing default_nslabs > to 1, was intended to allocate the minimum amount of memory possible, so > simply remove that minimal allocation period. > > Signed-off-by: Florian Fainelli Looks good, Reviewed-by: Christoph Hellwig