From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754865AbZC1UNr (ORCPT ); Sat, 28 Mar 2009 16:13:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751536AbZC1UNi (ORCPT ); Sat, 28 Mar 2009 16:13:38 -0400 Received: from hera.kernel.org ([140.211.167.34]:51342 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751211AbZC1UNi (ORCPT ); Sat, 28 Mar 2009 16:13:38 -0400 Message-ID: <49CE8499.6080003@kernel.org> Date: Sat, 28 Mar 2009 13:12:09 -0700 From: Yinghai Lu User-Agent: Thunderbird 2.0.0.19 (X11/20081227) MIME-Version: 1.0 To: Rusty Russell CC: Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Andrew Morton , Mike Travis , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] irq: remove wrong ifdef References: <49CDAB27.7050602@kernel.org> <49CDAB6E.90006@kernel.org> <200903281937.48755.rusty@rustcorp.com.au> In-Reply-To: <200903281937.48755.rusty@rustcorp.com.au> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Rusty Russell wrote: > On Saturday 28 March 2009 15:15:34 Yinghai Lu wrote: >> Impact: fix smp_affinity copying >> >> CPUMASKS_OFFSTACK is not defined anywhere. >> and init_allocate_desc_masks called before it set affinity to all cpus... >> >> just remove those #idef to make them get copied >> >> Signed-off-by: Yinghai Lu >> >> --- >> include/linux/irq.h | 4 ---- >> 1 file changed, 4 deletions(-) >> >> Index: linux-2.6/include/linux/irq.h >> =================================================================== >> --- linux-2.6.orig/include/linux/irq.h >> +++ linux-2.6/include/linux/irq.h >> @@ -468,20 +468,16 @@ static inline bool init_alloc_desc_masks >> * @new_desc: pointer to new irq_desc struct >> * >> * Insures affinity and pending_masks are copied to new irq_desc. >> - * If !CONFIG_CPUMASKS_OFFSTACK the cpumasks are embedded in the >> - * irq_desc struct so the copy is redundant. >> */ >> >> static inline void init_copy_desc_masks(struct irq_desc *old_desc, >> struct irq_desc *new_desc) >> { >> -#ifdef CONFIG_CPUMASKS_OFFSTACK >> cpumask_copy(new_desc->affinity, old_desc->affinity); >> >> #ifdef CONFIG_GENERIC_PENDING_IRQ >> cpumask_copy(new_desc->pending_mask, old_desc->pending_mask); >> #endif >> -#endif >> } >> >> #else /* !CONFIG_SMP */ > > Wow, that is supposed to be CONFIG_CPUMASK_OFFSTACK. > > The reason it is there is that we already do the memcpy of old_desc: this > extra copy is only needed if the cpumasks are external. But perhaps it's > an over-optimization. please check [PATCH] irq: correct CPUMASKS_OFFSTACK typo -v2 because init_alloc_desc_masks will set desc->affinity to all cpus even CPUMASK_OFFSET is not set. -v2 will seperate that function to alloc_desc_masks and init_desc_masks. YH