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Date:   Sat, 11 May 2019 23:45:20 +0200
From:   Andrea Parri <andrea.parri@amarulasolutions.com>
To:     "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Juri Lelli <juri.lelli@redhat.com>,
        Morten Rasmussen <morten.rasmussen@arm.com>, joelaf@google.com,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: Question about sched_setaffinity()
Message-ID: <20190511214520.GA3251@andrea>
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> > The below trace explain the issue. Some Paul person did it, see below.
> > It's broken per construction :-)
> 
> *facepalm*  Hence the very strange ->cpus_allowed mask.  I really
> should have figured that one out.
> 
> The fix is straightforward.  I just added "rcutorture.shuffle_interval=0"
> to the TRIVIAL.boot file, which stops rcutorture from shuffling its
> kthreads around.

I added the option to the file and I didn't reproduce the issue.


> Please accept my apologies for the hassle, and thank you for tracking
> this down!!!

Peter (echoing Paul):  Thank you for pointing that shuffler out!

  Andrea