]> git.proxmox.com Git - mirror_ubuntu-hirsute-kernel.git/commit
mm/debug_pagealloc.c: don't allocate page_ext if we don't use guard page
authorJoonsoo Kim <iamjoonsoo.kim@lge.com>
Fri, 7 Oct 2016 23:58:18 +0000 (16:58 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sat, 8 Oct 2016 01:46:27 +0000 (18:46 -0700)
commitf1c1e9f7b5b3ddce6b4f1986939ec87b27515086
tree114527f311ef32b5c8c0cc9f511a61c974c2c3f4
parentacbc15a4b397f86d39416df143e30982b1da528b
mm/debug_pagealloc.c: don't allocate page_ext if we don't use guard page

What debug_pagealloc does is just mapping/unmapping page table.
Basically, it doesn't need additional memory space to memorize
something.  But, with guard page feature, it requires additional memory
to distinguish if the page is for guard or not.  Guard page is only used
when debug_guardpage_minorder is non-zero so this patch removes
additional memory allocation (page_ext) if debug_guardpage_minorder is
zero.

It saves memory if we just use debug_pagealloc and not guard page.

Link: http://lkml.kernel.org/r/1471315879-32294-3-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/page_alloc.c