Re: WARNING: at kernel/rcutree.c:1558 rcu_do_batch+0x386/0x3a0(),during CPU hotplug

From: Peter Zijlstra
Date: Fri Sep 14 2012 - 08:25:23 EST


On Fri, 2012-09-14 at 17:48 +0530, Srivatsa S. Bhat wrote:
> #! /bin/bash

CPUPATH="/sys/devices/system/cpu"

> NUMBER_OF_CPUS=`ls -d /sys/devices/system/cpu/cpu[0-9]* | wc -l`

apply the above

> cd /sys/devices/system/cpu

skip this, so running the script doesn't change PWD

> while [ 1 ]

while :;

> do
> for ((i=1; i < NUMBER_OF_CPUS; i++))
> do
> sleep 1;

Also play with shorter sleeps like: sleep .1, I've found that higher
hotplug rate triggers some races faster.

> state=`cat cpu$i/online`
> if [ $state -eq 0 ]
> then
> echo 1 > cpu$i/online
> else
> echo 0 > cpu$i/online

echo $((state^1)) > $CPUPATH/cpu$i/online

> fi
> done
> done


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