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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Mike Galbraith <efault@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	LKML <linux-kernel@vger.kernel.org>,
	linux-rt-users@vger.kernel.org,
	Steven Rostedt <rostedt@goodmis.org>,
	Peter Zijlstra <peterz@infradead.org>
Subject: Re: v5.14-rc3-rt1 losing wakeups?
Date: Mon, 2 Aug 2021 09:02:18 +0200	[thread overview]
Message-ID: <20210802070218.5js3exubjxvsicx6@linutronix.de> (raw)
In-Reply-To: <ed1d5f9ec17a5b8d758c234562dad47cfc872ed8.camel@gmx.de>

On 2021-08-01 17:14:49 [+0200], Mike Galbraith wrote:
> On Sun, 2021-08-01 at 05:36 +0200, Mike Galbraith wrote:
> > On Fri, 2021-07-30 at 22:49 +0200, Thomas Gleixner wrote:
> > > >
> > > > First symptom is KDE/Plasma's task manager going comatose.  Notice soon
> > >
> > > KDE/Plasma points at the new fangled rtmutex based ww_mutex from
> > > Peter.
> >
> > Seems not.  When booting KVM box with nomodeset, there's exactly one
> > early boot ww_mutex lock/unlock, ancient history at the failure point.
> 
> As you've probably already surmised given it isn't the ww_mutex bits,
> it's the wake_q bits.  Apply the below, 5.14-rt ceases to fail.  Take
> perfectly healthy 5.13-rt, apply those bits, and it instantly begins
> failing as 5.14-rt had been.

Given what you have replied to the locking thread/
ww_mutex_lock_interruptible() may I assume that the wake_q bits are fine
and it is just the ww_mutex?

Sebastian

  reply	other threads:[~2021-08-02  7:02 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-30 11:07 [ANNOUNCE] v5.14-rc3-rt1 Sebastian Andrzej Siewior
2021-07-30 15:21 ` v5.14-rc3-rt1 losing wakeups? Mike Galbraith
2021-07-30 20:49   ` Thomas Gleixner
2021-07-31  1:03     ` Mike Galbraith
2021-07-31  3:33       ` Mike Galbraith
2021-07-31  8:50         ` Mike Galbraith
2021-08-01  3:36     ` Mike Galbraith
2021-08-01 15:14       ` Mike Galbraith
2021-08-02  7:02         ` Sebastian Andrzej Siewior [this message]
2021-08-02  7:18           ` Mike Galbraith
2021-08-02  8:25             ` Sebastian Andrzej Siewior
2021-08-02  8:40               ` Mike Galbraith
2021-08-02  9:12         ` Thomas Gleixner

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