1 #include <linux/mm.h>
2 #include <linux/mmzone.h>
3 #include <linux/bootmem.h>
4 #include <linux/bit_spinlock.h>
5 #include <linux/page_cgroup.h>
6 #include <linux/hash.h>
7 #include <linux/slab.h>
8 #include <linux/memory.h>
9 #include <linux/vmalloc.h>
10 #include <linux/cgroup.h>
11 #include <linux/swapops.h>
12
13 static void __meminit
__init_page_cgroup(struct page_cgroup * pc,unsigned long pfn)14 __init_page_cgroup(struct page_cgroup *pc, unsigned long pfn)
15 {
16 pc->flags = 0;
17 pc->mem_cgroup = NULL;
18 pc->page = pfn_to_page(pfn);
19 INIT_LIST_HEAD(&pc->lru);
20 }
21 static unsigned long total_usage;
22
23 #if !defined(CONFIG_SPARSEMEM)
24
25
pgdat_page_cgroup_init(struct pglist_data * pgdat)26 void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
27 {
28 pgdat->node_page_cgroup = NULL;
29 }
30
lookup_page_cgroup(struct page * page)31 struct page_cgroup *lookup_page_cgroup(struct page *page)
32 {
33 unsigned long pfn = page_to_pfn(page);
34 unsigned long offset;
35 struct page_cgroup *base;
36
37 base = NODE_DATA(page_to_nid(page))->node_page_cgroup;
38 if (unlikely(!base))
39 return NULL;
40
41 offset = pfn - NODE_DATA(page_to_nid(page))->node_start_pfn;
42 return base + offset;
43 }
44
alloc_node_page_cgroup(int nid)45 static int __init alloc_node_page_cgroup(int nid)
46 {
47 struct page_cgroup *base, *pc;
48 unsigned long table_size;
49 unsigned long start_pfn, nr_pages, index;
50
51 start_pfn = NODE_DATA(nid)->node_start_pfn;
52 nr_pages = NODE_DATA(nid)->node_spanned_pages;
53
54 if (!nr_pages)
55 return 0;
56
57 table_size = sizeof(struct page_cgroup) * nr_pages;
58
59 base = __alloc_bootmem_node_nopanic(NODE_DATA(nid),
60 table_size, PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
61 if (!base)
62 return -ENOMEM;
63 for (index = 0; index < nr_pages; index++) {
64 pc = base + index;
65 __init_page_cgroup(pc, start_pfn + index);
66 }
67 NODE_DATA(nid)->node_page_cgroup = base;
68 total_usage += table_size;
69 return 0;
70 }
71
page_cgroup_init(void)72 void __init page_cgroup_init(void)
73 {
74
75 int nid, fail;
76
77 if (mem_cgroup_disabled())
78 return;
79
80 for_each_online_node(nid) {
81 fail = alloc_node_page_cgroup(nid);
82 if (fail)
83 goto fail;
84 }
85 printk(KERN_INFO "allocated %ld bytes of page_cgroup\n", total_usage);
86 printk(KERN_INFO "please try cgroup_disable=memory option if you"
87 " don't want\n");
88 return;
89 fail:
90 printk(KERN_CRIT "allocation of page_cgroup was failed.\n");
91 printk(KERN_CRIT "please try cgroup_disable=memory boot option\n");
92 panic("Out of memory");
93 }
94
95 #else /* CONFIG_FLAT_NODE_MEM_MAP */
96
lookup_page_cgroup(struct page * page)97 struct page_cgroup *lookup_page_cgroup(struct page *page)
98 {
99 unsigned long pfn = page_to_pfn(page);
100 struct mem_section *section = __pfn_to_section(pfn);
101
102 return section->page_cgroup + pfn;
103 }
104
105 /* __alloc_bootmem...() is protected by !slab_available() */
init_section_page_cgroup(unsigned long pfn)106 static int __init_refok init_section_page_cgroup(unsigned long pfn)
107 {
108 struct mem_section *section = __pfn_to_section(pfn);
109 struct page_cgroup *base, *pc;
110 unsigned long table_size;
111 int nid, index;
112
113 if (!section->page_cgroup) {
114 nid = page_to_nid(pfn_to_page(pfn));
115 table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION;
116 if (slab_is_available()) {
117 base = kmalloc_node(table_size,
118 GFP_KERNEL | __GFP_NOWARN, nid);
119 if (!base)
120 base = vmalloc_node(table_size, nid);
121 } else {
122 base = __alloc_bootmem_node_nopanic(NODE_DATA(nid),
123 table_size,
124 PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
125 }
126 } else {
127 /*
128 * We don't have to allocate page_cgroup again, but
129 * address of memmap may be changed. So, we have to initialize
130 * again.
131 */
132 base = section->page_cgroup + pfn;
133 table_size = 0;
134 /* check address of memmap is changed or not. */
135 if (base->page == pfn_to_page(pfn))
136 return 0;
137 }
138
139 if (!base) {
140 printk(KERN_ERR "page cgroup allocation failure\n");
141 return -ENOMEM;
142 }
143
144 for (index = 0; index < PAGES_PER_SECTION; index++) {
145 pc = base + index;
146 __init_page_cgroup(pc, pfn + index);
147 }
148
149 section->page_cgroup = base - pfn;
150 total_usage += table_size;
151 return 0;
152 }
153 #ifdef CONFIG_MEMORY_HOTPLUG
__free_page_cgroup(unsigned long pfn)154 void __free_page_cgroup(unsigned long pfn)
155 {
156 struct mem_section *ms;
157 struct page_cgroup *base;
158
159 ms = __pfn_to_section(pfn);
160 if (!ms || !ms->page_cgroup)
161 return;
162 base = ms->page_cgroup + pfn;
163 if (is_vmalloc_addr(base)) {
164 vfree(base);
165 ms->page_cgroup = NULL;
166 } else {
167 struct page *page = virt_to_page(base);
168 if (!PageReserved(page)) { /* Is bootmem ? */
169 kfree(base);
170 ms->page_cgroup = NULL;
171 }
172 }
173 }
174
online_page_cgroup(unsigned long start_pfn,unsigned long nr_pages,int nid)175 int __meminit online_page_cgroup(unsigned long start_pfn,
176 unsigned long nr_pages,
177 int nid)
178 {
179 unsigned long start, end, pfn;
180 int fail = 0;
181
182 start = start_pfn & ~(PAGES_PER_SECTION - 1);
183 end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION);
184
185 for (pfn = start; !fail && pfn < end; pfn += PAGES_PER_SECTION) {
186 if (!pfn_present(pfn))
187 continue;
188 fail = init_section_page_cgroup(pfn);
189 }
190 if (!fail)
191 return 0;
192
193 /* rollback */
194 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION)
195 __free_page_cgroup(pfn);
196
197 return -ENOMEM;
198 }
199
offline_page_cgroup(unsigned long start_pfn,unsigned long nr_pages,int nid)200 int __meminit offline_page_cgroup(unsigned long start_pfn,
201 unsigned long nr_pages, int nid)
202 {
203 unsigned long start, end, pfn;
204
205 start = start_pfn & ~(PAGES_PER_SECTION - 1);
206 end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION);
207
208 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION)
209 __free_page_cgroup(pfn);
210 return 0;
211
212 }
213
page_cgroup_callback(struct notifier_block * self,unsigned long action,void * arg)214 static int __meminit page_cgroup_callback(struct notifier_block *self,
215 unsigned long action, void *arg)
216 {
217 struct memory_notify *mn = arg;
218 int ret = 0;
219 switch (action) {
220 case MEM_GOING_ONLINE:
221 ret = online_page_cgroup(mn->start_pfn,
222 mn->nr_pages, mn->status_change_nid);
223 break;
224 case MEM_OFFLINE:
225 offline_page_cgroup(mn->start_pfn,
226 mn->nr_pages, mn->status_change_nid);
227 break;
228 case MEM_CANCEL_ONLINE:
229 case MEM_GOING_OFFLINE:
230 break;
231 case MEM_ONLINE:
232 case MEM_CANCEL_OFFLINE:
233 break;
234 }
235
236 if (ret)
237 ret = notifier_from_errno(ret);
238 else
239 ret = NOTIFY_OK;
240
241 return ret;
242 }
243
244 #endif
245
page_cgroup_init(void)246 void __init page_cgroup_init(void)
247 {
248 unsigned long pfn;
249 int fail = 0;
250
251 if (mem_cgroup_disabled())
252 return;
253
254 for (pfn = 0; !fail && pfn < max_pfn; pfn += PAGES_PER_SECTION) {
255 if (!pfn_present(pfn))
256 continue;
257 fail = init_section_page_cgroup(pfn);
258 }
259 if (fail) {
260 printk(KERN_CRIT "try cgroup_disable=memory boot option\n");
261 panic("Out of memory");
262 } else {
263 hotplug_memory_notifier(page_cgroup_callback, 0);
264 }
265 printk(KERN_INFO "allocated %ld bytes of page_cgroup\n", total_usage);
266 printk(KERN_INFO "please try cgroup_disable=memory option if you don't"
267 " want\n");
268 }
269
pgdat_page_cgroup_init(struct pglist_data * pgdat)270 void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
271 {
272 return;
273 }
274
275 #endif
276
277
278 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
279
280 static DEFINE_MUTEX(swap_cgroup_mutex);
281 struct swap_cgroup_ctrl {
282 struct page **map;
283 unsigned long length;
284 };
285
286 struct swap_cgroup_ctrl swap_cgroup_ctrl[MAX_SWAPFILES];
287
288 /*
289 * This 8bytes seems big..maybe we can reduce this when we can use "id" for
290 * cgroup rather than pointer.
291 */
292 struct swap_cgroup {
293 struct mem_cgroup *val;
294 };
295 #define SC_PER_PAGE (PAGE_SIZE/sizeof(struct swap_cgroup))
296 #define SC_POS_MASK (SC_PER_PAGE - 1)
297
298 /*
299 * SwapCgroup implements "lookup" and "exchange" operations.
300 * In typical usage, this swap_cgroup is accessed via memcg's charge/uncharge
301 * against SwapCache. At swap_free(), this is accessed directly from swap.
302 *
303 * This means,
304 * - we have no race in "exchange" when we're accessed via SwapCache because
305 * SwapCache(and its swp_entry) is under lock.
306 * - When called via swap_free(), there is no user of this entry and no race.
307 * Then, we don't need lock around "exchange".
308 *
309 * TODO: we can push these buffers out to HIGHMEM.
310 */
311
312 /*
313 * allocate buffer for swap_cgroup.
314 */
swap_cgroup_prepare(int type)315 static int swap_cgroup_prepare(int type)
316 {
317 struct page *page;
318 struct swap_cgroup_ctrl *ctrl;
319 unsigned long idx, max;
320
321 if (!do_swap_account)
322 return 0;
323 ctrl = &swap_cgroup_ctrl[type];
324
325 for (idx = 0; idx < ctrl->length; idx++) {
326 page = alloc_page(GFP_KERNEL | __GFP_ZERO);
327 if (!page)
328 goto not_enough_page;
329 ctrl->map[idx] = page;
330 }
331 return 0;
332 not_enough_page:
333 max = idx;
334 for (idx = 0; idx < max; idx++)
335 __free_page(ctrl->map[idx]);
336
337 return -ENOMEM;
338 }
339
340 /**
341 * swap_cgroup_record - record mem_cgroup for this swp_entry.
342 * @ent: swap entry to be recorded into
343 * @mem: mem_cgroup to be recorded
344 *
345 * Returns old value at success, NULL at failure.
346 * (Of course, old value can be NULL.)
347 */
swap_cgroup_record(swp_entry_t ent,struct mem_cgroup * mem)348 struct mem_cgroup *swap_cgroup_record(swp_entry_t ent, struct mem_cgroup *mem)
349 {
350 int type = swp_type(ent);
351 unsigned long offset = swp_offset(ent);
352 unsigned long idx = offset / SC_PER_PAGE;
353 unsigned long pos = offset & SC_POS_MASK;
354 struct swap_cgroup_ctrl *ctrl;
355 struct page *mappage;
356 struct swap_cgroup *sc;
357 struct mem_cgroup *old;
358
359 if (!do_swap_account)
360 return NULL;
361
362 ctrl = &swap_cgroup_ctrl[type];
363
364 mappage = ctrl->map[idx];
365 sc = page_address(mappage);
366 sc += pos;
367 old = sc->val;
368 sc->val = mem;
369
370 return old;
371 }
372
373 /**
374 * lookup_swap_cgroup - lookup mem_cgroup tied to swap entry
375 * @ent: swap entry to be looked up.
376 *
377 * Returns pointer to mem_cgroup at success. NULL at failure.
378 */
lookup_swap_cgroup(swp_entry_t ent)379 struct mem_cgroup *lookup_swap_cgroup(swp_entry_t ent)
380 {
381 int type = swp_type(ent);
382 unsigned long offset = swp_offset(ent);
383 unsigned long idx = offset / SC_PER_PAGE;
384 unsigned long pos = offset & SC_POS_MASK;
385 struct swap_cgroup_ctrl *ctrl;
386 struct page *mappage;
387 struct swap_cgroup *sc;
388 struct mem_cgroup *ret;
389
390 if (!do_swap_account)
391 return NULL;
392
393 ctrl = &swap_cgroup_ctrl[type];
394 mappage = ctrl->map[idx];
395 sc = page_address(mappage);
396 sc += pos;
397 ret = sc->val;
398 return ret;
399 }
400
swap_cgroup_swapon(int type,unsigned long max_pages)401 int swap_cgroup_swapon(int type, unsigned long max_pages)
402 {
403 void *array;
404 unsigned long array_size;
405 unsigned long length;
406 struct swap_cgroup_ctrl *ctrl;
407
408 if (!do_swap_account)
409 return 0;
410
411 length = ((max_pages/SC_PER_PAGE) + 1);
412 array_size = length * sizeof(void *);
413
414 array = vmalloc(array_size);
415 if (!array)
416 goto nomem;
417
418 memset(array, 0, array_size);
419 ctrl = &swap_cgroup_ctrl[type];
420 mutex_lock(&swap_cgroup_mutex);
421 ctrl->length = length;
422 ctrl->map = array;
423 if (swap_cgroup_prepare(type)) {
424 /* memory shortage */
425 ctrl->map = NULL;
426 ctrl->length = 0;
427 vfree(array);
428 mutex_unlock(&swap_cgroup_mutex);
429 goto nomem;
430 }
431 mutex_unlock(&swap_cgroup_mutex);
432
433 printk(KERN_INFO
434 "swap_cgroup: uses %ld bytes of vmalloc for pointer array space"
435 " and %ld bytes to hold mem_cgroup pointers on swap\n",
436 array_size, length * PAGE_SIZE);
437 printk(KERN_INFO
438 "swap_cgroup can be disabled by noswapaccount boot option.\n");
439
440 return 0;
441 nomem:
442 printk(KERN_INFO "couldn't allocate enough memory for swap_cgroup.\n");
443 printk(KERN_INFO
444 "swap_cgroup can be disabled by noswapaccount boot option\n");
445 return -ENOMEM;
446 }
447
swap_cgroup_swapoff(int type)448 void swap_cgroup_swapoff(int type)
449 {
450 int i;
451 struct swap_cgroup_ctrl *ctrl;
452
453 if (!do_swap_account)
454 return;
455
456 mutex_lock(&swap_cgroup_mutex);
457 ctrl = &swap_cgroup_ctrl[type];
458 if (ctrl->map) {
459 for (i = 0; i < ctrl->length; i++) {
460 struct page *page = ctrl->map[i];
461 if (page)
462 __free_page(page);
463 }
464 vfree(ctrl->map);
465 ctrl->map = NULL;
466 ctrl->length = 0;
467 }
468 mutex_unlock(&swap_cgroup_mutex);
469 }
470
471 #endif
472