Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755250Ab1EEPZ6 (ORCPT ); Thu, 5 May 2011 11:25:58 -0400 Received: from rcsinet10.oracle.com ([148.87.113.121]:28802 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753361Ab1EEPZ4 (ORCPT ); Thu, 5 May 2011 11:25:56 -0400 Message-ID: <4DC2C12E.1070101@oracle.com> Date: Thu, 05 May 2011 10:24:30 -0500 From: Dave Kleikamp User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110503 Lightning/1.0b2 OracleBeehiveExtension/1.0.0.2-OracleInternal ObetStats/UAFCAFCATUAFLAF_1301673577011-962016341 Thunderbird/3.1.10 MIME-Version: 1.0 To: Andi Kleen CC: Thomas Gleixner , Chris Mason , Peter Zijlstra , Tim Chen , linux-kernel@vger.kernel.org, lenb@kernel.org, paulmck@us.ibm.com Subject: Re: idle issues running sembench on 128 cpus II References: <4DC1C95B.4040706@gmail.com> <20110504230349.GC2925@one.firstfloor.org> <20110504234241.GD2925@one.firstfloor.org> <20110504234806.GF2925@one.firstfloor.org> In-Reply-To: <20110504234806.GF2925@one.firstfloor.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Source-IP: acsinet21.oracle.com [141.146.126.237] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090208.4DC2C13E.00B2:SCFMA922111,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1797 Lines: 55 On 05/04/2011 06:48 PM, Andi Kleen wrote: >> Here's a new patch without the raw. Boots on my Westmere. > > Sorry appended the old patch. Here's really the new version. > > From: Andi Kleen > Date: Wed, 4 May 2011 15:09:27 -0700 > Subject: [PATCH] Move C3 stop test outside lock > > Avoid taking locks in the idle path for systems where the timer > doesn't stop in C3. > > Signed-off-by: Andi Kleen > > diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c > index da800ff..7f565b7 100644 > --- a/kernel/time/tick-broadcast.c > +++ b/kernel/time/tick-broadcast.c > @@ -456,23 +456,22 @@ void tick_broadcast_oneshot_control(unsigned long reason) > unsigned long flags; > int cpu; > > - raw_spin_lock_irqsave(&tick_broadcast_lock, flags); > - > /* > * Periodic mode does not care about the enter/exit of power > * states > */ > if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) > - goto out; > + return; > > - bc = tick_broadcast_device.evtdev; > cpu = smp_processor_id(); > + bc = tick_broadcast_device.evtdev; > td =&per_cpu(tick_cpu_device, cpu); > dev = td->evtdev; > > if (!(dev->features& CLOCK_EVT_FEAT_C3STOP)) > - goto out; > + return; out: is now defined but not used in this function. > > + raw_spin_lock_irqsave(&tick_broadcast_lock, flags); > if (reason == CLOCK_EVT_NOTIFY_BROADCAST_ENTER) { > if (!cpumask_test_cpu(cpu, tick_get_broadcast_oneshot_mask())) { > cpumask_set_cpu(cpu, tick_get_broadcast_oneshot_mask()); > -- 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/