From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261798AbUB0MEh (ORCPT ); Fri, 27 Feb 2004 07:04:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261806AbUB0MEh (ORCPT ); Fri, 27 Feb 2004 07:04:37 -0500 Received: from phoenix.infradead.org ([213.86.99.234]:45828 "EHLO phoenix.infradead.org") by vger.kernel.org with ESMTP id S261798AbUB0MEf (ORCPT ); Fri, 27 Feb 2004 07:04:35 -0500 Date: Fri, 27 Feb 2004 12:04:33 +0000 From: Christoph Hellwig To: Tim Bird Cc: linux kernel Subject: Re: Why no interrupt priorities? Message-ID: <20040227120433.A31544@infradead.org> Mail-Followup-To: Christoph Hellwig , Tim Bird , linux kernel References: <403E4363.2070908@am.sony.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <403E4363.2070908@am.sony.com>; from tim.bird@am.sony.com on Thu, Feb 26, 2004 at 11:05:07AM -0800 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 26, 2004 at 11:05:07AM -0800, Tim Bird wrote: > What's the rationale for not supporting interrupt priorities > in the kernel? What do you actually want to do them? Linux doesn't do the traditional unix spl scheme for coplexity and performance reasons, see www.usenix.org/publications/library/proceedings/ana97/full_papers/small/small.ps for a related paper. Give that linux hardirq handlers should be very small there's no performance gain in that area for sane architectures, too.