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Message-ID: <1443406620.3293.26.camel@gmail.com>
Subject: [v4.2+ regression] fd7a4bed sched, rt: Convert switched_{from,
 to}_rt() / prio_changed_rt() to balance callbacks
From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>, LKML <linux-kernel@vger.kernel.org>
Date: Mon, 28 Sep 2015 04:17:00 +0200
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Hi Peter,

I bumped into an odd futextest regression, and finally bisected it to
$subject.  I haven't poked at it yet, chasing down and confirming the
little bugger munched the day.

#!/bin/sh

cd /home/git/futextest/functional
trap "killall -KILL -q cpuhog;exit;" INT

for i in `seq 0 7`; do taskset -c $i cpuhog& done
sleep 1
for i in `seq 1000`
do
	echo iteration $i
	./futex_requeue_pi -c -b -o -t 500000
done
killall cpuhog


Without the cpuhogs, it won't hang.

	-Mike