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Date: Tue, 18 Oct 2016 01:25:59 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: "Luck, Tony" <tony.luck@intel.com>
cc: "Yu, Fenghua" <fenghua.yu@intel.com>,
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Subject: RE: [PATCH v4 13/18] x86/intel_rdt: Add mkdir to resctrl file
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On Mon, 17 Oct 2016, Luck, Tony wrote:

> > How so? CLOSID 9 is using CLOSID 1 L2 settings. Are we just keeping the L2
> > setting of CLOSID 1 around and do not reset it to default?
> 
> No. When CLOSID 9 arrives at the L2 h/w, it doesn't just take the bits it
> likes an discard the high bits to map to L2_CBM[1]. It just turns into 
> into the maximum allowed value for an L2 CBM.

So all CLOSIDs >= 8 will use all valid CBM bits for L2? That's even more
insane as this breaks any L2 partitioning which is set up by CLOSIDs < 8.

So effectively CLOSIDs >= 8 are useless in the L3=16 and L2=8 case.

Thanks,

	tglx