LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>
To: "Steven Rostedt" <rostedt@goodmis.org>, "Ingo Molnar" <mingo@elte.hu>
Cc: "LKML" <linux-kernel@vger.kernel.org>,
	"Linus Torvalds" <torvalds@linux-foundation.org>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Brown, Len" <len.brown@intel.com>,
	"Adam Belay" <abelay@novell.com>,
	"Peter Zijlstra" <a.p.zijlstra@chello.nl>,
	"Andi Kleen" <ak@suse.de>
Subject: RE: [PATCH] Kick CPUS that might be sleeping in cpus_idle_wait
Date: Thu, 10 Jan 2008 09:31:39 -0800	[thread overview]
Message-ID: <924EFEDD5F540B4284297C4DC59F3DEE5A2710@orsmsx423.amr.corp.intel.com> (raw)
In-Reply-To: <Pine.LNX.4.58.0801100936320.6420@gandalf.stny.rr.com>

 

>-----Original Message-----
>From: linux-kernel-owner@vger.kernel.org 
>[mailto:linux-kernel-owner@vger.kernel.org] On Behalf Of Steven Rostedt
>Sent: Thursday, January 10, 2008 6:44 AM
>To: Ingo Molnar
>Cc: LKML; Linus Torvalds; Andrew Morton; Thomas Gleixner; 
>Brown, Len; Pallipadi, Venkatesh; Adam Belay; Peter Zijlstra; 
>Andi Kleen
>Subject: Re: [PATCH] Kick CPUS that might be sleeping in cpus_idle_wait
>
>
>
>On Thu, 10 Jan 2008, Ingo Molnar wrote:
>> > FYI, I just hit this hang on 2.6.24-rc6 without any extra 
>patches. So,
>> > unless 2.6.24-rc7 did anything to fix this issue, this is a high
>> > priority bug (IMHO).
>>
>> i'm wondering why this only triggered now. Is this something new in
>> 2.6.24?
>
>It only triggeres with the switching of the idle governors. 
>And not just
>one, you need to switch twice. The first loading of a governor does not
>call cpu_idle_wait, but the second one does. NO_HZ must also 
>be enabled,
>plus this needs to happen when no events or threads are 
>scheduled to run
>on a CPU, which limits this to boot up.
>
>Also, this only seems to happen on my 2x2 (4way) and only once 
>in a while.
>
>I'm surprised that I'm the only one so far to report it. I can 
>boot up the
>2.6.23 kernel on this box to see if it also hangs sometimes. But, as I
>said, it may take several hundreds of tries to see it.


With 2.6.23, you can try compiling acpi processor.ko as a module and
doing insmod and rmmod in a loop. That should call cpu_idle_wait very
frequently.

Thanks,
Venki

  reply	other threads:[~2008-01-10 17:52 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-01-08  2:27 [RFC PATCH] kick sleeping idle CPUS on cpu_idle_wait Steven Rostedt
2008-01-08  3:33 ` Andi Kleen
2008-01-09 20:42   ` [PATCH] Kick CPUS that might be sleeping in cpus_idle_wait Steven Rostedt
2008-01-09 22:12     ` Steven Rostedt
2008-01-10 13:45       ` Ingo Molnar
2008-01-10 14:43         ` Steven Rostedt
2008-01-10 17:31           ` Pallipadi, Venkatesh [this message]
2008-01-10 18:03             ` Steven Rostedt
2008-01-09 23:42     ` Andrew Morton
2008-01-10  0:05       ` Steven Rostedt
2008-01-10  0:12     ` Pallipadi, Venkatesh
     [not found]     ` <B5B0CFF685D7DF46A05CF1678CFB42ED20E00653@orsmsx423.amr.corp.intel.com>
2008-02-08  1:05       ` [PATCH] x86: Simplify cpu_idle_wait Venki Pallipadi
2008-02-08 10:28         ` Andi Kleen
2008-02-08 17:24           ` Venki Pallipadi
2008-02-08 18:45             ` Andi Kleen
2008-02-09  9:33             ` Thomas Gleixner
2008-04-10 16:49               ` Venki Pallipadi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=924EFEDD5F540B4284297C4DC59F3DEE5A2710@orsmsx423.amr.corp.intel.com \
    --to=venkatesh.pallipadi@intel.com \
    --cc=a.p.zijlstra@chello.nl \
    --cc=abelay@novell.com \
    --cc=ak@suse.de \
    --cc=akpm@linux-foundation.org \
    --cc=len.brown@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=rostedt@goodmis.org \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.org \
    --subject='RE: [PATCH] Kick CPUS that might be sleeping in cpus_idle_wait' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).