include/linux/hugetlb_cgroup.h

   1 /*
   2  * Copyright IBM Corporation, 2012
   3  * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of version 2.1 of the GNU Lesser General Public License
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  12  *
  13  */
  14
  15 #ifndef _LINUX_HUGETLB_CGROUP_H
  16 #define _LINUX_HUGETLB_CGROUP_H
  17
  18 #include <linux/res_counter.h>
  19
  20 struct hugetlb_cgroup;
  21 /*
  22  * Minimum page order trackable by hugetlb cgroup.
  23  * At least 3 pages are necessary for all the tracking information.
  24  */
  25 #define HUGETLB_CGROUP_MIN_ORDER        2
  26
  27 #ifdef CONFIG_CGROUP_HUGETLB
  28
  29 static inline struct hugetlb_cgroup *hugetlb_cgroup_from_page(struct page *page)
  30 {
  31         VM_BUG_ON(!PageHuge(page));
  32
  33         if (compound_order(page) < HUGETLB_CGROUP_MIN_ORDER)
  34                 return NULL;
  35         return (struct hugetlb_cgroup *)page[2].lru.next;
  36 }
  37
  38 static inline
  39 int set_hugetlb_cgroup(struct page *page, struct hugetlb_cgroup *h_cg)
  40 {
  41         VM_BUG_ON(!PageHuge(page));
  42
  43         if (compound_order(page) < HUGETLB_CGROUP_MIN_ORDER)
  44                 return -1;
  45         page[2].lru.next = (void *)h_cg;
  46         return 0;
  47 }
  48
  49 static inline bool hugetlb_cgroup_disabled(void)
  50 {
  51         if (hugetlb_subsys.disabled)
  52                 return true;
  53         return false;
  54 }
  55
  56 #else
  57 static inline struct hugetlb_cgroup *hugetlb_cgroup_from_page(struct page *page)
  58 {
  59         return NULL;
  60 }
  61
  62 static inline
  63 int set_hugetlb_cgroup(struct page *page, struct hugetlb_cgroup *h_cg)
  64 {
  65         return 0;
  66 }
  67
  68 static inline bool hugetlb_cgroup_disabled(void)
  69 {
  70         return true;
  71 }
  72
  73 #endif  /* CONFIG_MEM_RES_CTLR_HUGETLB */
  74 #endif