s390/mm: better annotate 2KB pagetable fragments handling
authorAlexander Gordeev <agordeev@linux.ibm.com>
Thu, 4 Nov 2021 06:14:45 +0000 (07:14 +0100)
committerHeiko Carstens <hca@linux.ibm.com>
Thu, 16 Dec 2021 18:58:08 +0000 (19:58 +0100)
commit1194372db6f3c917c9c6f6907e8378cf1076c557
tree611fa39fd09dafadfb2b36d667cbd3930f9af013
parentc2c224932fd0ee6854d6ebfc8d059c2bcad86606
s390/mm: better annotate 2KB pagetable fragments handling

Explicitly encode immediate value of pending remove nibble
(bits 31-28) and tracking nibble (bits 27-24) of the page
refcount whenever these nibbles are tested or changed, for
better readability. Also, add some comments describing how
the fragments are handled.

Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
arch/s390/mm/pgalloc.c