hugetlb: add a list for tracking in-use HugeTLB pages

hugepage_activelist will be used to track currently used HugeTLB pages.
We need to find the in-use HugeTLB pages to support HugeTLB cgroup removal.
On cgroup removal we update the page's HugeTLB cgroup to point to parent
cgroup.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 0f23c1840c9b..ed550d819044 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -211,6 +211,7 @@ struct hstate {
         unsigned long resv_huge_pages;
         unsigned long surplus_huge_pages;
         unsigned long nr_overcommit_huge_pages;
+        struct list_head hugepage_activelist;
         struct list_head hugepage_freelists[MAX_NUMNODES];
         unsigned int nr_huge_pages_node[MAX_NUMNODES];
         unsigned int free_huge_pages_node[MAX_NUMNODES];