From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933186AbWKSUaG (ORCPT ); Sun, 19 Nov 2006 15:30:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933166AbWKSUaG (ORCPT ); Sun, 19 Nov 2006 15:30:06 -0500 Received: from h155.mvista.com ([63.81.120.155]:58285 "EHLO imap.sh.mvista.com") by vger.kernel.org with ESMTP id S933188AbWKSUaE (ORCPT ); Sun, 19 Nov 2006 15:30:04 -0500 Message-ID: <4560BF28.8010406@ru.mvista.com> Date: Sun, 19 Nov 2006 23:31:36 +0300 From: Sergei Shtylyov Organization: MontaVista Software Inc. User-Agent: Mozilla/5.0 (X11; U; Linux i686; rv:1.7.2) Gecko/20040803 X-Accept-Language: ru, en-us, en-gb MIME-Version: 1.0 To: Ingo Molnar Cc: Benjamin Herrenschmidt , linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, dwalker@mvista.com Subject: Re: [PATCH] 2.6.18-rt7: PowerPC: fix breakage in threaded fasteoi type IRQ handlers References: <200611192243.34850.sshtylyov@ru.mvista.com> <1163966437.5826.99.camel@localhost.localdomain> <20061119200650.GA22949@elte.hu> <1163967590.5826.104.camel@localhost.localdomain> <20061119202348.GA27649@elte.hu> In-Reply-To: <20061119202348.GA27649@elte.hu> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello. Ingo Molnar wrote: >>What do you need an ack() for on fasteoi ? On all fasteoi controllers >>I have, ack is implicit by obtaining the vector number and all there >>is is an eoi... > it's a compatibility hack only. Threaded handlers are a different type > of flow, but often the fasteoi handler is not changed to the threaded > handler so i changed it to be a threaded handler too. The fasteoi flow seem to only had been used for x86 IOAPIC in the RT patch only *before* PPC took to using them in the mainline... > threaded handlers need a mask() + an ack(), because that's the correct Not all of them. This could be customized on type-by-type basis. I.e. we could call eoi() instead of ack() for fasteoi chips without having to resort to the duplicated ack/eoi handlers. > model to map them to kernel threads - threaded handlers can be delayed > for a long time if something higher-prio is preempting them. > > Ingo WBR, Sergei