x86/intel_rdt: Add cpus_list rdtgroup file
authorJiri Olsa <jolsa@redhat.com>
Mon, 10 Apr 2017 14:52:32 +0000 (16:52 +0200)
committerThomas Gleixner <tglx@linutronix.de>
Mon, 10 Apr 2017 17:10:25 +0000 (19:10 +0200)
commit4ffa3c977b5da2907eb294dc6d0259a02f2284aa
tree7267158eb409425c430d92efcfd529757ed436cb
parent17f8ba1dca072ce66c25b9e74ea2500b029594a0
x86/intel_rdt: Add cpus_list rdtgroup file

The resource control filesystem provides only a bitmask based cpus file for
assigning CPUs to a resource group. That's cumbersome with large cpumasks
and non-intuitive when modifying the file from the command line.

Range based cpu lists are commonly used along with bitmask based cpu files
in various subsystems throughout the kernel.

Add 'cpus_list' file which is CPU range based.

  # cd /sys/fs/resctrl/
  # echo 1-10 > krava/cpus_list
  # cat krava/cpus_list
  1-10
  # cat krava/cpus
  0007fe
  # cat cpus
  fffff9
  # cat cpus_list
  0,3-23

[ tglx: Massaged changelog and replaced "bitmask lists" by "CPU ranges" ]

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Shaohua Li <shli@fb.com>
Link: http://lkml.kernel.org/r/20170410145232.GF25354@krava
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Documentation/x86/intel_rdt_ui.txt
arch/x86/include/asm/intel_rdt.h
arch/x86/kernel/cpu/intel_rdt_rdtgroup.c