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Message-ID: <1332498333.16159.9.camel@twins>
Subject: RE: [PATCH] Fix the race between smp_call_function and CPU booting
From: Peter Zijlstra <peterz@infradead.org>
To: "Liu, Chuansheng" <chuansheng.liu@intel.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Yanmin Zhang <yanmin_zhang@linux.intel.com>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
        "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Date: Fri, 23 Mar 2012 11:25:33 +0100
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On Thu, 2012-03-22 at 00:59 +0000, Liu, Chuansheng wrote:
> Below is the complete test patch. Just run the simpl_loop_onoffline.sh
> and simpl_loop_smpcalling.sh concurrently
> to reproduce the race.
> 
What I did was:

for i in {2..23} ; do echo 0 > /sys/devices/system/cpu/cpu${i}/online ; done
while usleep 50000 ; do echo 1 > /debug/smp_call_test ; done &
while :; do echo $i > /sys/devices/system/cpu/cpu1/online ; let i^=1 ; done

and this has been running for well over 30 minutes.. is there anything
else one needs to do?