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Date: Wed, 16 Aug 2017 16:57:41 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: "Luck, Tony" <tony.luck@intel.com>
cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>,
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Subject: RE: [PATCH 1/2] x86/intel_rdt/mbm: Fix MBM overflow handler during
 hot cpu
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On Wed, 16 Aug 2017, Luck, Tony wrote:
> > You could alternatively use flush and make the worker code schedule the
> > work on a still online CPU in the domain instead of blindly rescheduling it
> > on the same CPU.
> 
> We looked at that when you suggested flush. The problem is that we have
> already deleted the current cpu from the bitmask for the domain. So the
> worker code doesn't know which domain it is running on, so can't pick
> another.
> 
> If we try to do the flush before dropping the cpu from the bitmask, then
> the worker code doesn't have any reason to pick a different CPU.
> 
> Is there is some cheap "I'm running on a CPU that is in the process of going
> offline" test that we could make in the worker code?

Don't think so. It was just a thought, but the code as provided is fine and
merged as is.

Thanks,

	tglx