hwmon: (sht15) add support for the status register
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / mm / page_cgroup.c
blob2daadc322ba61678cfc9120e3b65c551b5b96d2d
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 #include <linux/kmemleak.h>
14 static void __meminit init_page_cgroup(struct page_cgroup *pc, unsigned long id)
16 pc->flags = 0;
17 set_page_cgroup_array_id(pc, id);
18 pc->mem_cgroup = NULL;
19 INIT_LIST_HEAD(&pc->lru);
21 static unsigned long total_usage;
23 #if !defined(CONFIG_SPARSEMEM)
26 void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
28 pgdat->node_page_cgroup = NULL;
31 struct page_cgroup *lookup_page_cgroup(struct page *page)
33 unsigned long pfn = page_to_pfn(page);
34 unsigned long offset;
35 struct page_cgroup *base;
37 base = NODE_DATA(page_to_nid(page))->node_page_cgroup;
38 if (unlikely(!base))
39 return NULL;
41 offset = pfn - NODE_DATA(page_to_nid(page))->node_start_pfn;
42 return base + offset;
45 struct page *lookup_cgroup_page(struct page_cgroup *pc)
47 unsigned long pfn;
48 struct page *page;
49 pg_data_t *pgdat;
51 pgdat = NODE_DATA(page_cgroup_array_id(pc));
52 pfn = pc - pgdat->node_page_cgroup + pgdat->node_start_pfn;
53 page = pfn_to_page(pfn);
54 VM_BUG_ON(pc != lookup_page_cgroup(page));
55 return page;
58 static int __init alloc_node_page_cgroup(int nid)
60 struct page_cgroup *base, *pc;
61 unsigned long table_size;
62 unsigned long start_pfn, nr_pages, index;
64 start_pfn = NODE_DATA(nid)->node_start_pfn;
65 nr_pages = NODE_DATA(nid)->node_spanned_pages;
67 if (!nr_pages)
68 return 0;
70 table_size = sizeof(struct page_cgroup) * nr_pages;
72 base = __alloc_bootmem_node_nopanic(NODE_DATA(nid),
73 table_size, PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
74 if (!base)
75 return -ENOMEM;
76 for (index = 0; index < nr_pages; index++) {
77 pc = base + index;
78 init_page_cgroup(pc, nid);
80 NODE_DATA(nid)->node_page_cgroup = base;
81 total_usage += table_size;
82 return 0;
85 void __init page_cgroup_init_flatmem(void)
88 int nid, fail;
90 if (mem_cgroup_disabled())
91 return;
93 for_each_online_node(nid) {
94 fail = alloc_node_page_cgroup(nid);
95 if (fail)
96 goto fail;
98 printk(KERN_INFO "allocated %ld bytes of page_cgroup\n", total_usage);
99 printk(KERN_INFO "please try 'cgroup_disable=memory' option if you"
100 " don't want memory cgroups\n");
101 return;
102 fail:
103 printk(KERN_CRIT "allocation of page_cgroup failed.\n");
104 printk(KERN_CRIT "please try 'cgroup_disable=memory' boot option\n");
105 panic("Out of memory");
108 #else /* CONFIG_FLAT_NODE_MEM_MAP */
110 struct page_cgroup *lookup_page_cgroup(struct page *page)
112 unsigned long pfn = page_to_pfn(page);
113 struct mem_section *section = __pfn_to_section(pfn);
115 if (!section->page_cgroup)
116 return NULL;
117 return section->page_cgroup + pfn;
120 struct page *lookup_cgroup_page(struct page_cgroup *pc)
122 struct mem_section *section;
123 struct page *page;
124 unsigned long nr;
126 nr = page_cgroup_array_id(pc);
127 section = __nr_to_section(nr);
128 page = pfn_to_page(pc - section->page_cgroup);
129 VM_BUG_ON(pc != lookup_page_cgroup(page));
130 return page;
133 static void *__init_refok alloc_page_cgroup(size_t size, int nid)
135 void *addr = NULL;
137 addr = alloc_pages_exact_nid(nid, size, GFP_KERNEL | __GFP_NOWARN);
138 if (addr)
139 return addr;
141 if (node_state(nid, N_HIGH_MEMORY))
142 addr = vmalloc_node(size, nid);
143 else
144 addr = vmalloc(size);
146 return addr;
149 #ifdef CONFIG_MEMORY_HOTPLUG
150 static void free_page_cgroup(void *addr)
152 if (is_vmalloc_addr(addr)) {
153 vfree(addr);
154 } else {
155 struct page *page = virt_to_page(addr);
156 size_t table_size =
157 sizeof(struct page_cgroup) * PAGES_PER_SECTION;
159 BUG_ON(PageReserved(page));
160 free_pages_exact(addr, table_size);
163 #endif
165 static int __init_refok init_section_page_cgroup(unsigned long pfn)
167 struct page_cgroup *base, *pc;
168 struct mem_section *section;
169 unsigned long table_size;
170 unsigned long nr;
171 int nid, index;
173 nr = pfn_to_section_nr(pfn);
174 section = __nr_to_section(nr);
176 if (section->page_cgroup)
177 return 0;
179 nid = page_to_nid(pfn_to_page(pfn));
180 table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION;
181 base = alloc_page_cgroup(table_size, nid);
184 * The value stored in section->page_cgroup is (base - pfn)
185 * and it does not point to the memory block allocated above,
186 * causing kmemleak false positives.
188 kmemleak_not_leak(base);
190 if (!base) {
191 printk(KERN_ERR "page cgroup allocation failure\n");
192 return -ENOMEM;
195 for (index = 0; index < PAGES_PER_SECTION; index++) {
196 pc = base + index;
197 init_page_cgroup(pc, nr);
200 section->page_cgroup = base - pfn;
201 total_usage += table_size;
202 return 0;
204 #ifdef CONFIG_MEMORY_HOTPLUG
205 void __free_page_cgroup(unsigned long pfn)
207 struct mem_section *ms;
208 struct page_cgroup *base;
210 ms = __pfn_to_section(pfn);
211 if (!ms || !ms->page_cgroup)
212 return;
213 base = ms->page_cgroup + pfn;
214 free_page_cgroup(base);
215 ms->page_cgroup = NULL;
218 int __meminit online_page_cgroup(unsigned long start_pfn,
219 unsigned long nr_pages,
220 int nid)
222 unsigned long start, end, pfn;
223 int fail = 0;
225 start = start_pfn & ~(PAGES_PER_SECTION - 1);
226 end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION);
228 for (pfn = start; !fail && pfn < end; pfn += PAGES_PER_SECTION) {
229 if (!pfn_present(pfn))
230 continue;
231 fail = init_section_page_cgroup(pfn);
233 if (!fail)
234 return 0;
236 /* rollback */
237 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION)
238 __free_page_cgroup(pfn);
240 return -ENOMEM;
243 int __meminit offline_page_cgroup(unsigned long start_pfn,
244 unsigned long nr_pages, int nid)
246 unsigned long start, end, pfn;
248 start = start_pfn & ~(PAGES_PER_SECTION - 1);
249 end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION);
251 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION)
252 __free_page_cgroup(pfn);
253 return 0;
257 static int __meminit page_cgroup_callback(struct notifier_block *self,
258 unsigned long action, void *arg)
260 struct memory_notify *mn = arg;
261 int ret = 0;
262 switch (action) {
263 case MEM_GOING_ONLINE:
264 ret = online_page_cgroup(mn->start_pfn,
265 mn->nr_pages, mn->status_change_nid);
266 break;
267 case MEM_OFFLINE:
268 offline_page_cgroup(mn->start_pfn,
269 mn->nr_pages, mn->status_change_nid);
270 break;
271 case MEM_CANCEL_ONLINE:
272 case MEM_GOING_OFFLINE:
273 break;
274 case MEM_ONLINE:
275 case MEM_CANCEL_OFFLINE:
276 break;
279 return notifier_from_errno(ret);
282 #endif
284 void __init page_cgroup_init(void)
286 unsigned long pfn;
287 int fail = 0;
289 if (mem_cgroup_disabled())
290 return;
292 for (pfn = 0; !fail && pfn < max_pfn; pfn += PAGES_PER_SECTION) {
293 if (!pfn_present(pfn))
294 continue;
295 fail = init_section_page_cgroup(pfn);
297 if (fail) {
298 printk(KERN_CRIT "try 'cgroup_disable=memory' boot option\n");
299 panic("Out of memory");
300 } else {
301 hotplug_memory_notifier(page_cgroup_callback, 0);
303 printk(KERN_INFO "allocated %ld bytes of page_cgroup\n", total_usage);
304 printk(KERN_INFO "please try 'cgroup_disable=memory' option if you don't"
305 " want memory cgroups\n");
308 void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
310 return;
313 #endif
316 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
318 static DEFINE_MUTEX(swap_cgroup_mutex);
319 struct swap_cgroup_ctrl {
320 struct page **map;
321 unsigned long length;
322 spinlock_t lock;
325 struct swap_cgroup_ctrl swap_cgroup_ctrl[MAX_SWAPFILES];
327 struct swap_cgroup {
328 unsigned short id;
330 #define SC_PER_PAGE (PAGE_SIZE/sizeof(struct swap_cgroup))
331 #define SC_POS_MASK (SC_PER_PAGE - 1)
334 * SwapCgroup implements "lookup" and "exchange" operations.
335 * In typical usage, this swap_cgroup is accessed via memcg's charge/uncharge
336 * against SwapCache. At swap_free(), this is accessed directly from swap.
338 * This means,
339 * - we have no race in "exchange" when we're accessed via SwapCache because
340 * SwapCache(and its swp_entry) is under lock.
341 * - When called via swap_free(), there is no user of this entry and no race.
342 * Then, we don't need lock around "exchange".
344 * TODO: we can push these buffers out to HIGHMEM.
348 * allocate buffer for swap_cgroup.
350 static int swap_cgroup_prepare(int type)
352 struct page *page;
353 struct swap_cgroup_ctrl *ctrl;
354 unsigned long idx, max;
356 ctrl = &swap_cgroup_ctrl[type];
358 for (idx = 0; idx < ctrl->length; idx++) {
359 page = alloc_page(GFP_KERNEL | __GFP_ZERO);
360 if (!page)
361 goto not_enough_page;
362 ctrl->map[idx] = page;
364 return 0;
365 not_enough_page:
366 max = idx;
367 for (idx = 0; idx < max; idx++)
368 __free_page(ctrl->map[idx]);
370 return -ENOMEM;
374 * swap_cgroup_cmpxchg - cmpxchg mem_cgroup's id for this swp_entry.
375 * @end: swap entry to be cmpxchged
376 * @old: old id
377 * @new: new id
379 * Returns old id at success, 0 at failure.
380 * (There is no mem_cgroup using 0 as its id)
382 unsigned short swap_cgroup_cmpxchg(swp_entry_t ent,
383 unsigned short old, unsigned short new)
385 int type = swp_type(ent);
386 unsigned long offset = swp_offset(ent);
387 unsigned long idx = offset / SC_PER_PAGE;
388 unsigned long pos = offset & SC_POS_MASK;
389 struct swap_cgroup_ctrl *ctrl;
390 struct page *mappage;
391 struct swap_cgroup *sc;
392 unsigned long flags;
393 unsigned short retval;
395 ctrl = &swap_cgroup_ctrl[type];
397 mappage = ctrl->map[idx];
398 sc = page_address(mappage);
399 sc += pos;
400 spin_lock_irqsave(&ctrl->lock, flags);
401 retval = sc->id;
402 if (retval == old)
403 sc->id = new;
404 else
405 retval = 0;
406 spin_unlock_irqrestore(&ctrl->lock, flags);
407 return retval;
411 * swap_cgroup_record - record mem_cgroup for this swp_entry.
412 * @ent: swap entry to be recorded into
413 * @mem: mem_cgroup to be recorded
415 * Returns old value at success, 0 at failure.
416 * (Of course, old value can be 0.)
418 unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)
420 int type = swp_type(ent);
421 unsigned long offset = swp_offset(ent);
422 unsigned long idx = offset / SC_PER_PAGE;
423 unsigned long pos = offset & SC_POS_MASK;
424 struct swap_cgroup_ctrl *ctrl;
425 struct page *mappage;
426 struct swap_cgroup *sc;
427 unsigned short old;
428 unsigned long flags;
430 ctrl = &swap_cgroup_ctrl[type];
432 mappage = ctrl->map[idx];
433 sc = page_address(mappage);
434 sc += pos;
435 spin_lock_irqsave(&ctrl->lock, flags);
436 old = sc->id;
437 sc->id = id;
438 spin_unlock_irqrestore(&ctrl->lock, flags);
440 return old;
444 * lookup_swap_cgroup - lookup mem_cgroup tied to swap entry
445 * @ent: swap entry to be looked up.
447 * Returns CSS ID of mem_cgroup at success. 0 at failure. (0 is invalid ID)
449 unsigned short lookup_swap_cgroup(swp_entry_t ent)
451 int type = swp_type(ent);
452 unsigned long offset = swp_offset(ent);
453 unsigned long idx = offset / SC_PER_PAGE;
454 unsigned long pos = offset & SC_POS_MASK;
455 struct swap_cgroup_ctrl *ctrl;
456 struct page *mappage;
457 struct swap_cgroup *sc;
458 unsigned short ret;
460 ctrl = &swap_cgroup_ctrl[type];
461 mappage = ctrl->map[idx];
462 sc = page_address(mappage);
463 sc += pos;
464 ret = sc->id;
465 return ret;
468 int swap_cgroup_swapon(int type, unsigned long max_pages)
470 void *array;
471 unsigned long array_size;
472 unsigned long length;
473 struct swap_cgroup_ctrl *ctrl;
475 if (!do_swap_account)
476 return 0;
478 length = ((max_pages/SC_PER_PAGE) + 1);
479 array_size = length * sizeof(void *);
481 array = vmalloc(array_size);
482 if (!array)
483 goto nomem;
485 memset(array, 0, array_size);
486 ctrl = &swap_cgroup_ctrl[type];
487 mutex_lock(&swap_cgroup_mutex);
488 ctrl->length = length;
489 ctrl->map = array;
490 spin_lock_init(&ctrl->lock);
491 if (swap_cgroup_prepare(type)) {
492 /* memory shortage */
493 ctrl->map = NULL;
494 ctrl->length = 0;
495 vfree(array);
496 mutex_unlock(&swap_cgroup_mutex);
497 goto nomem;
499 mutex_unlock(&swap_cgroup_mutex);
501 return 0;
502 nomem:
503 printk(KERN_INFO "couldn't allocate enough memory for swap_cgroup.\n");
504 printk(KERN_INFO
505 "swap_cgroup can be disabled by noswapaccount boot option\n");
506 return -ENOMEM;
509 void swap_cgroup_swapoff(int type)
511 int i;
512 struct swap_cgroup_ctrl *ctrl;
514 if (!do_swap_account)
515 return;
517 mutex_lock(&swap_cgroup_mutex);
518 ctrl = &swap_cgroup_ctrl[type];
519 if (ctrl->map) {
520 for (i = 0; i < ctrl->length; i++) {
521 struct page *page = ctrl->map[i];
522 if (page)
523 __free_page(page);
525 vfree(ctrl->map);
526 ctrl->map = NULL;
527 ctrl->length = 0;
529 mutex_unlock(&swap_cgroup_mutex);
532 #endif