From: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx>
The out-of-tree KSM used ioctls on fds cloned from /dev/ksm to register
a memory area for merging: we prefer now to use an madvise(2) interface.
This patch just defines MADV_MERGEABLE (to tell KSM it may merge pages
in this area found identical to pages in other mergeable areas) and
MADV_UNMERGEABLE (to undo that).
Most architectures use asm-generic, but alpha, mips, parisc, xtensa
need their own definitions: included here for mmotm convenience, but
we'll probably want to split this and feed pieces to arch maintainers.
Based upon earlier patches by Chris Wright and Izik Eidus.
Signed-off-by: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx>
Signed-off-by: Chris Wright <chrisw@xxxxxxxxxx>
Signed-off-by: Izik Eidus <ieidus@xxxxxxxxxx>