From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757109AbYBERUA (ORCPT ); Tue, 5 Feb 2008 12:20:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752778AbYBERTw (ORCPT ); Tue, 5 Feb 2008 12:19:52 -0500 Received: from sinclair.provo.novell.com ([137.65.248.137]:35299 "EHLO sinclair.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752560AbYBERTv convert rfc822-to-8bit (ORCPT ); Tue, 5 Feb 2008 12:19:51 -0500 Message-Id: <47A852E8.BA47.005A.0@novell.com> X-Mailer: Novell GroupWise Internet Agent 7.0.2 HP Date: Tue, 05 Feb 2008 10:13:28 -0700 From: "Gregory Haskins" To: "Daniel Walker" Cc: "Ingo Molnar" , "Max Krasnyanskiy" , "LKML" , Subject: Re: CPU hotplug and IRQ affinity with 2.6.24-rt1 References: <47A7A131.8040800@qualcomm.com> <20080205025144.GA31774@dwalker1.mvista.com> <47A7A784.BA47.005A.0@novell.com> <20080205165936.GA18613@dwalker1.mvista.com> In-Reply-To: <20080205165936.GA18613@dwalker1.mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>> On Tue, Feb 5, 2008 at 11:59 AM, in message <20080205165936.GA18613@dwalker1.mvista.com>, Daniel Walker wrote: > On Mon, Feb 04, 2008 at 10:02:12PM -0700, Gregory Haskins wrote: >> >>> On Mon, Feb 4, 2008 at 9:51 PM, in message >> <20080205025144.GA31774@dwalker1.mvista.com>, Daniel Walker >> wrote: >> > I get the following when I tried it, >> > >> > BUG: sleeping function called from invalid context bash(5126) at >> > kernel/rtmutex.c:638 >> > in_atomic():1 [00000001], irqs_disabled():1 >> >> Hi Daniel, >> Can you try this patch and let me know if it fixes your problem? >> >> ----------------------- >> >> use rcu for root-domain kfree >> >> Signed-off-by: Gregory Haskins >> >> diff --git a/kernel/sched.c b/kernel/sched.c >> index e6ad493..77e86c1 100644 >> --- a/kernel/sched.c >> +++ b/kernel/sched.c >> @@ -339,6 +339,7 @@ struct root_domain { >> atomic_t refcount; >> cpumask_t span; >> cpumask_t online; >> + struct rcu_head rcu; >> >> /* >> * The "RT overload" flag: it gets set if a CPU has more than >> @@ -6222,6 +6223,12 @@ sd_parent_degenerate(struct sched_domain *sd, struct > sched_domain *parent) >> return 1; >> } >> >> +/* rcu callback to free a root-domain */ >> +static void rq_free_root(struct rcu_head *rcu) >> +{ >> + kfree(container_of(rcu, struct root_domain, rcu)); >> +} >> + > > I looked at the code a bit, and I'm not sure you need this complexity.. > Once you have replace the old_rq, there is no reason it needs to > protection of the run queue spinlock .. So you could just move the kfree > down below the spin_unlock_irqrestore() .. Indeed. When I looked last night at the stack, I thought the in_atomic was coming from further up in the trace. I see the issue now, thanks Daniel. (Anyone have a spare brown bag?) -Greg > > Daniel > - > To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html