[PATCH 0/2] x86/resctrl: Support wider MBM counters

[Reinette Chatre <reinette.chatre@intel.com>]

Memory Bandwidth Monitoring (MBM) is an Intel Resource Director
Technology (RDT) feature that tracks Total and Local bandwidth
generated which misses the L3 cache.

The original Memory Bandwidth Monitoring (MBM) architectural
definition defines counters of up to 62 bits and the first-generation
MBM implementation uses 24 bit counters. Software is required to poll
at 1 second or faster to ensure that data is retrieved before a counter
rollover occurs more than once under worst conditions.

As system bandwidths scale the software requirement is maintained with
the introduction of a per-resource enumerable MBM counter width.

This series adds support for the new enumerable MBM counter width.

Details about the feature can be found in Chapter 9 of the most
recent Intel ISE available from
https://software.intel.com/sites/default/files/managed/c5/15/architecture-instruction-set-extensions-programming-reference.pdf

Reinette Chatre (2):
  x86/resctrl: Maintain MBM counter width per resource
  x86/resctrl: Support CPUID enumeration of MBM counter width

 arch/x86/include/asm/processor.h          |  1 +
 arch/x86/kernel/cpu/common.c              |  5 +++++
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  8 ++++---
 arch/x86/kernel/cpu/resctrl/internal.h    | 15 ++++++++++---
 arch/x86/kernel/cpu/resctrl/monitor.c     | 27 ++++++++++++++++-------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    |  2 +-
 6 files changed, 43 insertions(+), 15 deletions(-)

-- 
2.21.0