x86/mm/cpa: Add large page preservation statistics

The large page preservation mechanism is just magic and provides no
information at all. Add optional statistic output in debugfs so the magic can
be evaluated. Defaults is off.

Output:

 1G pages checked:                    2
 1G pages sameprot:                   0
 1G pages preserved:                  0
 2M pages checked:                  540
 2M pages sameprot:                 466
 2M pages preserved:                 47
 4K pages checked:               800770
 4K pages set-checked:             7668

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Dave Hansen <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Bin Yang <[email protected]>
Cc: Mark Gross <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

0 files changed, 0 insertions, 0 deletions