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/mmdebug.h>
 19
 20struct hugetlb_cgroup;
 21struct resv_map;
 22struct file_region;
 23
 24/*
 25 * Minimum page order trackable by hugetlb cgroup.
 26 * At least 4 pages are necessary for all the tracking information.
 27 * The second tail page (hpage[2]) is the fault usage cgroup.
 28 * The third tail page (hpage[3]) is the reservation usage cgroup.
 29 */
 30#define HUGETLB_CGROUP_MIN_ORDER	2
 31
 32#ifdef CONFIG_CGROUP_HUGETLB
 33enum hugetlb_memory_event {
 34	HUGETLB_MAX,
 35	HUGETLB_NR_MEMORY_EVENTS,
 36};
 37
 38struct hugetlb_cgroup {
 39	struct cgroup_subsys_state css;
 40
 41	/*
 42	 * the counter to account for hugepages from hugetlb.
 43	 */
 44	struct page_counter hugepage[HUGE_MAX_HSTATE];
 45
 46	/*
 47	 * the counter to account for hugepage reservations from hugetlb.
 48	 */
 49	struct page_counter rsvd_hugepage[HUGE_MAX_HSTATE];
 50
 51	atomic_long_t events[HUGE_MAX_HSTATE][HUGETLB_NR_MEMORY_EVENTS];
 52	atomic_long_t events_local[HUGE_MAX_HSTATE][HUGETLB_NR_MEMORY_EVENTS];
 53
 54	/* Handle for "hugetlb.events" */
 55	struct cgroup_file events_file[HUGE_MAX_HSTATE];
 56
 57	/* Handle for "hugetlb.events.local" */
 58	struct cgroup_file events_local_file[HUGE_MAX_HSTATE];
 59};
 60
 61static inline struct hugetlb_cgroup *
 62__hugetlb_cgroup_from_page(struct page *page, bool rsvd)
 63{
 64	VM_BUG_ON_PAGE(!PageHuge(page), page);
 65
 66	if (compound_order(page) < HUGETLB_CGROUP_MIN_ORDER)
 67		return NULL;
 68	if (rsvd)
 69		return (struct hugetlb_cgroup *)page[3].private;
 70	else
 71		return (struct hugetlb_cgroup *)page[2].private;
 72}
 73
 74static inline struct hugetlb_cgroup *hugetlb_cgroup_from_page(struct page *page)
 75{
 76	return __hugetlb_cgroup_from_page(page, false);
 77}
 78
 79static inline struct hugetlb_cgroup *
 80hugetlb_cgroup_from_page_rsvd(struct page *page)
 81{
 82	return __hugetlb_cgroup_from_page(page, true);
 83}
 84
 85static inline int __set_hugetlb_cgroup(struct page *page,
 86				       struct hugetlb_cgroup *h_cg, bool rsvd)
 87{
 88	VM_BUG_ON_PAGE(!PageHuge(page), page);
 89
 90	if (compound_order(page) < HUGETLB_CGROUP_MIN_ORDER)
 91		return -1;
 92	if (rsvd)
 93		page[3].private = (unsigned long)h_cg;
 94	else
 95		page[2].private = (unsigned long)h_cg;
 96	return 0;
 97}
 98
 99static inline int set_hugetlb_cgroup(struct page *page,
100				     struct hugetlb_cgroup *h_cg)
101{
102	return __set_hugetlb_cgroup(page, h_cg, false);
103}
104
105static inline int set_hugetlb_cgroup_rsvd(struct page *page,
106					  struct hugetlb_cgroup *h_cg)
107{
108	return __set_hugetlb_cgroup(page, h_cg, true);
109}
110
111static inline bool hugetlb_cgroup_disabled(void)
112{
113	return !cgroup_subsys_enabled(hugetlb_cgrp_subsys);
114}
115
116extern int hugetlb_cgroup_charge_cgroup(int idx, unsigned long nr_pages,
117					struct hugetlb_cgroup **ptr);
118extern int hugetlb_cgroup_charge_cgroup_rsvd(int idx, unsigned long nr_pages,
119					     struct hugetlb_cgroup **ptr);
120extern void hugetlb_cgroup_commit_charge(int idx, unsigned long nr_pages,
121					 struct hugetlb_cgroup *h_cg,
122					 struct page *page);
123extern void hugetlb_cgroup_commit_charge_rsvd(int idx, unsigned long nr_pages,
124					      struct hugetlb_cgroup *h_cg,
125					      struct page *page);
126extern void hugetlb_cgroup_uncharge_page(int idx, unsigned long nr_pages,
127					 struct page *page);
128extern void hugetlb_cgroup_uncharge_page_rsvd(int idx, unsigned long nr_pages,
129					      struct page *page);
130
131extern void hugetlb_cgroup_uncharge_cgroup(int idx, unsigned long nr_pages,
132					   struct hugetlb_cgroup *h_cg);
133extern void hugetlb_cgroup_uncharge_cgroup_rsvd(int idx, unsigned long nr_pages,
134						struct hugetlb_cgroup *h_cg);
135extern void hugetlb_cgroup_uncharge_counter(struct resv_map *resv,
136					    unsigned long start,
137					    unsigned long end);
138
139extern void hugetlb_cgroup_uncharge_file_region(struct resv_map *resv,
140						struct file_region *rg,
141						unsigned long nr_pages);
142
143extern void hugetlb_cgroup_file_init(void) __init;
144extern void hugetlb_cgroup_migrate(struct page *oldhpage,
145				   struct page *newhpage);
146
147#else
148static inline void hugetlb_cgroup_uncharge_file_region(struct resv_map *resv,
149						       struct file_region *rg,
150						       unsigned long nr_pages)
151{
152}
153
154static inline struct hugetlb_cgroup *hugetlb_cgroup_from_page(struct page *page)
155{
156	return NULL;
157}
158
159static inline struct hugetlb_cgroup *
160hugetlb_cgroup_from_page_resv(struct page *page)
161{
162	return NULL;
163}
164
165static inline struct hugetlb_cgroup *
166hugetlb_cgroup_from_page_rsvd(struct page *page)
167{
168	return NULL;
169}
170
171static inline int set_hugetlb_cgroup(struct page *page,
172				     struct hugetlb_cgroup *h_cg)
173{
174	return 0;
175}
176
177static inline int set_hugetlb_cgroup_rsvd(struct page *page,
178					  struct hugetlb_cgroup *h_cg)
179{
180	return 0;
181}
182
183static inline bool hugetlb_cgroup_disabled(void)
184{
185	return true;
186}
187
188static inline int hugetlb_cgroup_charge_cgroup(int idx, unsigned long nr_pages,
189					       struct hugetlb_cgroup **ptr)
190{
191	return 0;
192}
193
194static inline int hugetlb_cgroup_charge_cgroup_rsvd(int idx,
195						    unsigned long nr_pages,
196						    struct hugetlb_cgroup **ptr)
197{
198	return 0;
199}
200
201static inline void hugetlb_cgroup_commit_charge(int idx, unsigned long nr_pages,
202						struct hugetlb_cgroup *h_cg,
203						struct page *page)
204{
205}
206
207static inline void
208hugetlb_cgroup_commit_charge_rsvd(int idx, unsigned long nr_pages,
209				  struct hugetlb_cgroup *h_cg,
210				  struct page *page)
211{
212}
213
214static inline void hugetlb_cgroup_uncharge_page(int idx, unsigned long nr_pages,
215						struct page *page)
216{
217}
218
219static inline void hugetlb_cgroup_uncharge_page_rsvd(int idx,
220						     unsigned long nr_pages,
221						     struct page *page)
222{
223}
224static inline void hugetlb_cgroup_uncharge_cgroup(int idx,
225						  unsigned long nr_pages,
226						  struct hugetlb_cgroup *h_cg)
227{
228}
229
230static inline void
231hugetlb_cgroup_uncharge_cgroup_rsvd(int idx, unsigned long nr_pages,
232				    struct hugetlb_cgroup *h_cg)
233{
234}
235
236static inline void hugetlb_cgroup_uncharge_counter(struct resv_map *resv,
237						   unsigned long start,
238						   unsigned long end)
239{
240}
241
242static inline void hugetlb_cgroup_file_init(void)
243{
244}
245
246static inline void hugetlb_cgroup_migrate(struct page *oldhpage,
247					  struct page *newhpage)
248{
249}
250
251#endif  /* CONFIG_MEM_RES_CTLR_HUGETLB */
252#endif