From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161121AbXDKAQe (ORCPT ); Tue, 10 Apr 2007 20:16:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161133AbXDKAQe (ORCPT ); Tue, 10 Apr 2007 20:16:34 -0400 Received: from mga09.intel.com ([134.134.136.24]:13239 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161121AbXDKAQd (ORCPT ); Tue, 10 Apr 2007 20:16:33 -0400 X-ExtLoop1: 1 X-IronPort-AV: i="4.14,392,1170662400"; d="scan'208"; a="71637792:sNHT19297683" Date: Tue, 10 Apr 2007 17:15:14 -0700 From: Venki Pallipadi To: Adam Belay , Andi Kleen , eranian@hpl.hp.com Cc: Venki Pallipadi , "Rafael J. Wysocki" , Andrew Morton , linux-kernel@vger.kernel.org, randy.dunlap@oracle.com, lenb@kernel.org Subject: Re: 2.6.21-rc6-mm1 Message-ID: <20070411001513.GA2975@linux-os.sc.intel.com> References: <653FFBB4508B9042B5D43DC9E18836F539ADFB@scsmsx415.amr.corp.intel.com> <200704091940.53439.rjw@sisk.pl> <1176249569.32554.229.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1176249569.32554.229.camel@localhost.localdomain> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 10, 2007 at 07:59:29PM -0400, Adam Belay wrote: > On Tue, 2007-04-10 at 15:20 -0700, Venki Pallipadi wrote: > > On Mon, Apr 09, 2007 at 07:40:52PM +0200, Rafael J. Wysocki wrote: > > > On Monday, 9 April 2007 18:14, Pallipadi, Venkatesh wrote: > > > > > > > > >-----Original Message----- > > > > >From: Rafael J. Wysocki [mailto:rjw@sisk.pl] > > > > >Sent: Monday, April 09, 2007 9:08 AM > > > > >To: Andrew Morton > > > > >Cc: linux-kernel@vger.kernel.org; randy.dunlap@oracle.com; > > > > >lenb@kernel.org; Pallipadi, Venkatesh > > > > >Subject: Re: 2.6.21-rc6-mm1 > > > > > > > > > >On Sunday, 8 April 2007 23:35, Andrew Morton wrote: > > > > >> > > > > >> > > > > >ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2 > > > > >.6.21-rc6/2.6.21-rc6-mm1/ > > > > >> > > > > >> > > > > >> - Lots of x86 updates > > > > >> > > > > >> - This is a 25MB diff against mainline, which is rather large. > > > > > > > > > >The cpuidle thing tends to hang my x86-64 machines on boot. > > > > > > > > > > > > > Hi Rafael, > > > > > > > > At what point during boot does it hang? > > > > > > When mounting the root filesystem. It hangs completely, even the magic SysRq > > > doesn't work > > > > > > > Rafael: Below patch should fix the hang. > > Len: Please include this patch in acpi-test. > > > > Thanks, > > Venki > > > > Prevent hang on x86-64, when ACPI processor driver is added as a module on > > a system that does not support C-states. > > > > x86-64 expects all idle handlers to enable interrupts before returning from > > idle handler. This is due to enter_idle(), exit_idle() races. Make > > cpuidle_idle_call() confirm to this when there is no pm_idle_old. > > > > Also, cpuidle look at the return values of attch_driver() and set > > current_driver to NULL if attach fails on all CPUs. > > My vote would be to instead remove enter_idle() and exit_idle() from > x86-64, just as was done with i386. Performance monitoring > infrastructure shouldn't be interfering with the idle interrupt > delivery, as that could only hurt performance... Besides, there's > probably a better way of doing this than an idle notifier anyway. > Agreed. I did not like local_irq_enable() in cpuidle either, but added it anyway as it was a corner case when cpuidle is active and no driver is active and not a common case. I thought we will have it as a bandaid solution until enter_idle, exit_idle is around. Andi/Stephane: What are the plans around enter_idle exit_idle in x86-64. Is it still being used by perfmon for x86-64 arch? Thanks, Venki