linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Frank Rowand <frank.rowand@am.sony.com>
Cc: "Rowand, Frank" <Frank_Rowand@sonyusa.com>,
	Peter Zijlstra <peterz@infradead.org>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	linux-rt-users <linux-rt-users@vger.kernel.org>,
	Mike Galbraith <efault@gmx.de>
Subject: Re: [ANNOUNCE] 3.0.1-rt11
Date: Mon, 29 Aug 2011 20:17:20 -0700	[thread overview]
Message-ID: <20110830031720.GC2218@linux.vnet.ibm.com> (raw)
In-Reply-To: <4E5BEF21.6040908@am.sony.com>

On Mon, Aug 29, 2011 at 12:57:21PM -0700, Frank Rowand wrote:
> On 08/26/11 16:55, Paul E. McKenney wrote:
> > On Wed, Aug 24, 2011 at 04:58:49PM -0700, Frank Rowand wrote:
> >> On 08/13/11 03:53, Peter Zijlstra wrote:
> >>>
> >>> Whee, I can skip release announcements too!
> >>>
> >>> So no the subject ain't no mistake its not, 3.0.1-rt11 is there for the
> >>> grabs.
> >>>
> >>> Changes include (including the missing -rt10):
> >>>
> >>>   - hrtimer fix that should make RT_GROUP work again
> >>>   - RCU fixes that should make the RCU stalls go away
> >>>   - fixes SMP=n builds after breaking them in -rt9
> >>
> >> I have a consistent (every boot) hang on boot.  With a few
> >> hacks to get console output, I get the
> >>
> >>   rcu_preempt_state detected stalls on CPUs/tasks
> >>
> >> messages in the attached console log.
> 
> < snip >
> 
> > 
> > Hmmm...  The last few that I have seen that looked like this were
> > due to my messing up rcutorture so that the RCU-boost testing kthreads
> > ran CPU-bound at real-time priority.
> > 
> > Is it possible that something similar is happening on your system?
> > 
> >                                                         Thanx, Paul
> 
> I don't think so.  That would require CONFIG_RCU_TORTURE_TEST, correct?
> And that is not set:
> 
> < way big snip >
> 
> >> # CONFIG_RCU_TORTURE_TEST is not set
> >> CONFIG_RCU_CPU_STALL_TIMEOUT=60
> >> CONFIG_RCU_CPU_STALL_VERBOSE=y
> 
> I'm finally getting back to this today, so I'm starting to learn about
> the RCU stall detector, so maybe I can make some more sense of this.

This condition does not require CONFIG_RCU_TORTURE_TEST, rather, my
bug in CONFIG_RCU_TORTURE_TEST was one way to make this happen.  Any
condition that prevents RCU_SOFTIRQ from ever executing can cause these
symptoms.

							Thanx, Paul

  reply	other threads:[~2011-08-30  3:17 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-08-13 10:53 [ANNOUNCE] 3.0.1-rt11 Peter Zijlstra
2011-08-13 11:48 ` Mike Galbraith
2011-08-13 11:58   ` Peter Zijlstra
2011-08-13 13:59     ` Mike Galbraith
2011-08-13 14:23       ` Peter Zijlstra
2011-08-13 16:27       ` Paul E. McKenney
2011-08-14  4:23         ` Mike Galbraith
2011-08-16 14:17           ` Nivedita Singhvi
2011-08-16 15:10             ` Mike Galbraith
2011-08-16 15:18               ` Nivedita Singhvi
2011-08-16 19:31               ` Paul E. McKenney
2011-08-17  4:28                 ` Mike Galbraith
2011-08-17  5:03                   ` Nivedita Singhvi
2011-08-15 10:09         ` Mike Galbraith
2011-08-14 21:19 ` Clark Williams
2011-08-23 14:12 ` [patch] sched, rt: fix migrate_enable() thinko Mike Galbraith
2011-09-08  2:11   ` Frank Rowand
2011-09-08  4:58     ` Mike Galbraith
2011-08-24 23:58 ` [ANNOUNCE] 3.0.1-rt11 Frank Rowand
2011-08-26 23:55   ` Paul E. McKenney
2011-08-29 19:57     ` Frank Rowand
2011-08-30  3:17       ` Paul E. McKenney [this message]
2011-09-07  2:53     ` Frank Rowand
2011-09-07  3:00       ` Frank Rowand
2011-09-07  6:42       ` Paul E. McKenney
2011-09-07  9:25       ` Thomas Gleixner
2011-09-07 10:46         ` Russell King - ARM Linux
2011-09-07 10:47           ` Russell King - ARM Linux
2011-09-07 10:57             ` Thomas Gleixner
2011-09-07 14:01               ` Russell King - ARM Linux
2011-09-07 16:32                 ` Thomas Gleixner
2011-09-07 16:33                 ` Frank Rowand

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=20110830031720.GC2218@linux.vnet.ibm.com \
    --to=paulmck@linux.vnet.ibm.com \
    --cc=Frank_Rowand@sonyusa.com \
    --cc=efault@gmx.de \
    --cc=frank.rowand@am.sony.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rt-users@vger.kernel.org \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
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).