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Subject: Re: 2.6.14-rc4-rt7
From: Steven Rostedt <rostedt@goodmis.org>
To: john stultz <johnstul@us.ibm.com>
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On Wed, 2005-10-26 at 18:22 -0700, john stultz wrote:

> 
> I don't know if that would really fix it, because ideally you want to
> read the prev_mono_time at the same point you calculate the time inside
> the read lock'ed critical section.

Ideally yes, but this is just for debugging, so as long as prev is read
before now, this should prevent false positives due to ordering.  But
I'm not sure if my patch did anything regardless, since the
prev_mono_time is a cpu variable, and the get_cpu and put_cpu implement
a preempt_disable, so unless an interrupt is changing it, it should be
OK.

-- Steve