public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Ingo Molnar <mingo@elte.hu>
To: Rui Nuno Capela <rncbc@rncbc.org>
Cc: linux-kernel@vger.kernel.org, Lee Revell <rlrevell@joe-job.com>,
	mark_h_johnson@raytheon.com, "K.R. Foley" <kr@cybsft.com>,
	Bill Huey <bhuey@lnxw.com>, Adam Heath <doogie@debian.org>,
	Florian Schmidt <mista.tapas@gmx.net>,
	Thomas Gleixner <tglx@linutronix.de>,
	Michal Schmidt <xschmi00@stud.feec.vutbr.cz>,
	Fernando Pablo Lopez-Lezcano <nando@ccrma.stanford.edu>,
	Karsten Wiese <annabellesgarden@yahoo.de>,
	Gunther Persoons <gunther_persoons@spymac.com>,
	emann@mrv.com, Shane Shrybman <shrybman@aei.ca>,
	Amit Shah <amit.shah@codito.com>,
	Esben Nielsen <simlo@phys.au.dk>
Subject: Re: Real-Time Preemption, -RT-2.6.10-rc2-mm3-V0.7.31-7
Date: Wed, 1 Dec 2004 16:40:47 +0100	[thread overview]
Message-ID: <20041201154046.GA15244@elte.hu> (raw)
In-Reply-To: <32831.192.168.1.5.1101905229.squirrel@192.168.1.5>


ok, got the latest traces from Rui offlist.

here's a summary of an xrun that went like this:

   jackd-4711  00000000 0.002ms (+0.000ms): do_poll (sys_poll)
   ...
   jackd-4711  80000002 0.012ms (+0.000ms): dequeue_task (deactivate_task)
   ...
   IRQ 5-3052  ........ 1.946ms (+0.000ms): ->    jackd-4711
                     [ 00000027 00000001 ]: try_to_wake_up
   ...
qjackctl-4719  ........ 2.362ms (+0.000ms): common_interrupt:
                     [ b75e9090 00000005 00000000 ]
   ...
   IRQ 5-3052  00000000 2.473ms (+0.000ms): xrun (snd_pcm_period_elapsed)
   ...

this shows an interesting phenomenon: for whatever reason IRQ5's thread
didnt run until timestamp 1.946ms. There is lots of idle time between
timestamps 0.012ms and 1.946ms, so this must be some weird condition. 

Rui, could you activate trace_freerunning and send me a couple of 'big'
traces that result out of it? Apparently there is some other, earlier
activity that caused this to happen to IRQ5. Nothing seems to have woken
up IRQ5 when it ran, which is weird by itself too.

if IRQ thread 5 got delayed somehow that might explain the xrun: the
hardware interrupt had no chance to run. But how IRQ5 could stay on the
runqueue while the idle thread managed to run is strange.

	Ingo

  reply	other threads:[~2004-12-01 15:42 UTC|newest]

Thread overview: 65+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-11-26 12:12 Real-Time Preemption, -RT-2.6.10-rc2-mm3-V0.7.31-7 Rui Nuno Capela
2004-11-29 11:05 ` Ingo Molnar
2004-11-29 11:16 ` Ingo Molnar
2004-11-29 11:24   ` Ingo Molnar
2004-11-29 15:42     ` Ingo Molnar
2004-11-29 13:13   ` Rui Nuno Capela
2004-11-29 14:33     ` Ingo Molnar
2004-11-29 15:23       ` Ingo Molnar
2004-11-29 23:16         ` Real-Time Preemption, -RT-2.6.10-rc2-mm3-V0.7.31-13 Gene Heskett
2004-11-30  1:50           ` K.R. Foley
2004-11-30  3:19             ` Gene Heskett
2004-11-30  4:54             ` Gene Heskett
2004-11-30 15:26               ` K.R. Foley
2004-11-30 16:24                 ` Gene Heskett
2004-11-30 16:52                   ` Zwane Mwaikambo
2004-12-01  7:16                     ` Gene Heskett
2004-11-30 16:57                   ` K.R. Foley
2004-11-30 10:29         ` Real-Time Preemption, -RT-2.6.10-rc2-mm3-V0.7.31-7 Rui Nuno Capela
2004-11-30 13:19           ` Ingo Molnar
2004-11-30 15:39             ` Rui Nuno Capela
2004-11-30 16:42               ` Ingo Molnar
2004-12-01 10:32               ` Ingo Molnar
2004-12-01 11:25                 ` Ingo Molnar
2004-12-01 12:49                   ` Rui Nuno Capela
2004-12-01 12:47                 ` Rui Nuno Capela
2004-12-01 15:40                   ` Ingo Molnar [this message]
2004-12-01 16:06                     ` Ingo Molnar
2004-12-01 16:20                       ` [patch] Real-Time Preemption, -RT-2.6.10-rc2-mm3-V0.7.31-19 Ingo Molnar
2004-12-01 16:31                         ` Ingo Molnar
2004-12-01 18:59                         ` Rui Nuno Capela
2004-12-01 21:29                           ` Ingo Molnar
2004-12-01 21:30                             ` Ingo Molnar
     [not found]                               ` <32788.192.168.1.8.1101938057.squirrel@192.168.1.8>
2004-12-01 21:58                                 ` Ingo Molnar
2004-12-01 22:04                                   ` Rui Nuno Capela
2004-12-01 22:09                                 ` Ingo Molnar
2004-12-01 22:31                                   ` Rui Nuno Capela
2004-12-02  9:12                                     ` Rui Nuno Capela
2004-12-02 12:59                                       ` Rui Nuno Capela
2004-12-02 16:38                                         ` Fernando Lopez-Lezcano
2004-12-01 22:43                                   ` Florian Schmidt
2004-12-02  8:40                                     ` Ingo Molnar
2004-12-02 12:22                                       ` Florian Schmidt
2004-12-02 12:29                                         ` Ingo Molnar
2004-12-02 13:06                                           ` Florian Schmidt
2004-12-02 13:10                                             ` Ingo Molnar
2004-12-02 13:40                                               ` Florian Schmidt
2004-12-02 13:49                                                 ` Ingo Molnar
2004-12-02 16:08                                                   ` Florian Schmidt
2004-12-02 17:44                                                   ` Florian Schmidt
2004-12-02 21:12                                                     ` Florian Schmidt
2004-12-02 13:18                                             ` Rui Nuno Capela
2004-12-03  1:41                         ` Fernando Lopez-Lezcano
2004-12-03  2:23                           ` Fernando Lopez-Lezcano
2004-11-30 18:13   ` Real-Time Preemption, -RT-2.6.10-rc2-mm3-V0.7.31-7 Remi Colinet
2004-11-30  8:15     ` Ingo Molnar
2004-12-01  8:30       ` Eran Mann
2004-12-01  8:53         ` Ingo Molnar
2004-12-01 18:19           ` Adam Heath
  -- strict thread matches above, loose matches on Subject: below --
2004-11-28 19:42 Eran Mann
2004-11-30  8:58 ` Ingo Molnar
2004-11-30 16:20   ` Gene Heskett
2004-11-30 14:33 Mark_H_Johnson
2004-12-01  9:02 ` Ingo Molnar
2004-12-01 14:57 Mark_H_Johnson
2004-12-01 21:20 ` Ingo Molnar

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=20041201154046.GA15244@elte.hu \
    --to=mingo@elte.hu \
    --cc=amit.shah@codito.com \
    --cc=annabellesgarden@yahoo.de \
    --cc=bhuey@lnxw.com \
    --cc=doogie@debian.org \
    --cc=emann@mrv.com \
    --cc=gunther_persoons@spymac.com \
    --cc=kr@cybsft.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mark_h_johnson@raytheon.com \
    --cc=mista.tapas@gmx.net \
    --cc=nando@ccrma.stanford.edu \
    --cc=rlrevell@joe-job.com \
    --cc=rncbc@rncbc.org \
    --cc=shrybman@aei.ca \
    --cc=simlo@phys.au.dk \
    --cc=tglx@linutronix.de \
    --cc=xschmi00@stud.feec.vutbr.cz \
    /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