From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751631AbWIUWAp (ORCPT ); Thu, 21 Sep 2006 18:00:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751632AbWIUWAp (ORCPT ); Thu, 21 Sep 2006 18:00:45 -0400 Received: from gate.crashing.org ([63.228.1.57]:45712 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S1751630AbWIUWAo (ORCPT ); Thu, 21 Sep 2006 18:00:44 -0400 Subject: Re: [PATCH 2/3] FRV: Permit __do_IRQ() to be dispensed with From: Benjamin Herrenschmidt To: David Howells Cc: Ingo Molnar , torvalds@osdl.org, akpm@osdl.org, linux-kernel@vger.kernel.org, uclinux-dev@uclinux.org In-Reply-To: <339.1158844334@warthog.cambridge.redhat.com> References: <1157786802.31071.171.camel@localhost.localdomain> <20060908153236.21015.56106.stgit@warthog.cambridge.redhat.com> <20060908153240.21015.67367.stgit@warthog.cambridge.redhat.com> <20060909051211.GA6922@elte.hu> <339.1158844334@warthog.cambridge.redhat.com> Content-Type: text/plain Date: Fri, 22 Sep 2006 07:59:42 +1000 Message-Id: <1158875982.26347.125.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.6.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2006-09-21 at 14:12 +0100, David Howells wrote: > Benjamin Herrenschmidt wrote: > > > It can't optimize __do_IRQ() out in any case if one uses > > generic_handle_irq() because of the test in there which can't be > > predicted at compile time. > > Do you realise that powerpc still uses __do_IRQ if CONFIG_IRQSTACKS=y? You > should probably fix that. At the moment, there is no hurry as this code is shared with arch/ppc which hasn't been ported to genirq, so we need to handle both cases. (Though I'm not sure we ever get CONFIG_IRQSTACKS with arch/ppc ... I should probably check). The code uses desc->handle_irq and falls back to __do_IRQ() if that is NULL. Ben.