hugetlb_cgroup: add accounting for shared mappings

For shared mappings, the pointer to the hugetlb_cgroup to uncharge lives
in the resv_map entries, in file_region->reservation_counter.

After a call to region_chg, we charge the approprate hugetlb_cgroup, and
if successful, we pass on the hugetlb_cgroup info to a follow up
region_add call.  When a file_region entry is added to the resv_map via
region_add, we put the pointer to that cgroup in
file_region->reservation_counter.  If charging doesn't succeed, we report
the error to the caller, so that the kernel fails the reservation.

On region_del, which is when the hugetlb memory is unreserved, we also
uncharge the file_region->reservation_counter.

[akpm@linux-foundation.org: forward declare struct file_region]
Signed-off-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/20200211213128.73302-5-almasrymina@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mina Almasry 2020-04-01 21:11:28 -07:00 committed by Linus Torvalds
parent 0db9d74ed8
commit 075a61d07a
4 changed files with 155 additions and 54 deletions

View file

@ -19,6 +19,7 @@
struct hugetlb_cgroup;
struct resv_map;
struct file_region;
/*
* Minimum page order trackable by hugetlb cgroup.
@ -135,11 +136,21 @@ extern void hugetlb_cgroup_uncharge_counter(struct resv_map *resv,
unsigned long start,
unsigned long end);
extern void hugetlb_cgroup_uncharge_file_region(struct resv_map *resv,
struct file_region *rg,
unsigned long nr_pages);
extern void hugetlb_cgroup_file_init(void) __init;
extern void hugetlb_cgroup_migrate(struct page *oldhpage,
struct page *newhpage);
#else
static inline void hugetlb_cgroup_uncharge_file_region(struct resv_map *resv,
struct file_region *rg,
unsigned long nr_pages)
{
}
static inline struct hugetlb_cgroup *hugetlb_cgroup_from_page(struct page *page)
{
return NULL;