Documentation/ABI/testing/ppc-memtrace

   1 What:           /sys/kernel/debug/powerpc/memtrace
   2 Date:           Aug 2017
   3 KernelVersion:  4.14
   4 Contact:        linuxppc-dev@lists.ozlabs.org
   5 Description:    This folder contains the relevant debugfs files for the
   6                 hardware trace macro to use. CONFIG_PPC64_HARDWARE_TRACING
   7                 must be set.
   8
   9 What:           /sys/kernel/debug/powerpc/memtrace/enable
  10 Date:           Aug 2017
  11 KernelVersion:  4.14
  12 Contact:        linuxppc-dev@lists.ozlabs.org
  13 Description:    Write an integer containing the size in bytes of the memory
  14                 you want removed from each NUMA node to this file - it must be
  15                 aligned to the memblock size. This amount of RAM will be removed
  16                 from the kernel mappings and the following debugfs files will be
  17                 created. This can only be successfully done once per boot. Once
  18                 memory is successfully removed from each node, the following
  19                 files are created.
  20
  21 What:           /sys/kernel/debug/powerpc/memtrace/<node-id>
  22 Date:           Aug 2017
  23 KernelVersion:  4.14
  24 Contact:        linuxppc-dev@lists.ozlabs.org
  25 Description:    This directory contains information about the removed memory
  26                 from the specific NUMA node.
  27
  28 What:           /sys/kernel/debug/powerpc/memtrace/<node-id>/size
  29 Date:           Aug 2017
  30 KernelVersion:  4.14
  31 Contact:        linuxppc-dev@lists.ozlabs.org
  32 Description:    This contains the size of the memory removed from the node.
  33
  34 What:           /sys/kernel/debug/powerpc/memtrace/<node-id>/start
  35 Date:           Aug 2017
  36 KernelVersion:  4.14
  37 Contact:        linuxppc-dev@lists.ozlabs.org
  38 Description:    This contains the start address of the removed memory.
  39
  40 What:           /sys/kernel/debug/powerpc/memtrace/<node-id>/trace
  41 Date:           Aug 2017
  42 KernelVersion:  4.14
  43 Contact:        linuxppc-dev@lists.ozlabs.org
  44 Description:    This is where the hardware trace macro will output the trace
  45                 it generates.