Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758247Ab3CYJjG (ORCPT ); Mon, 25 Mar 2013 05:39:06 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:50936 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752573Ab3CYJjC (ORCPT ); Mon, 25 Mar 2013 05:39:02 -0400 X-IronPort-AV: E=Sophos;i="4.87,344,1363104000"; d="scan'208";a="6939713" Message-ID: <51501BB6.5000306@cn.fujitsu.com> Date: Mon, 25 Mar 2013 17:41:10 +0800 From: Lin Feng User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Lenky Gao CC: linux-kernel@vger.kernel.org, yinghai@kernel.org, mingo@elte.hu, gorcunov@gmail.com, rusty@rustcorp.com.au, sivanich@sgi.com, agordeev@redhat.com Subject: Re: Question: How to distribute the interrupts over multiple cores? References: <514FBD6E.2030706@cn.fujitsu.com> <514FC385.4030008@cn.fujitsu.com> <514FDE5F.5020500@cn.fujitsu.com> <514FF70A.6080402@cn.fujitsu.com> In-Reply-To: X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/03/25 17:38:16, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/03/25 17:38:17, Serialize complete at 2013/03/25 17:38:17 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 941 Lines: 30 Hi, On 03/25/2013 05:00 PM, Lenky Gao wrote: > I have found a comment in function physflat_cpu_mask_to_apicid to explain why. > > static unsigned int physflat_cpu_mask_to_apicid(const struct cpumask *cpumask) > { > int cpu; > > /* > * We're using fixed IRQ delivery, can only return one phys APIC ID. > * May as well be the first. > */ > ... > > This is mean i can not distribute the interrupts over multiple cores > when the machine have more than 8 cores? > > Sorry I can't find physflat_cpu_mask_to_apicid() in latest Linux tree, seems it has been removed out.. But just consider what you said that it's limited by "8 cores" IMHO it's impossible or it is a bug. thanks, linfeng -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/