memcg: remove redundant message at swapon
[linux-2.6.git] / mm / page_cgroup.c
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
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
26 void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
27 {
28         pgdat->node_page_cgroup = NULL;
29 }
30
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
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
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
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() */
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
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
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
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
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
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
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 struct swap_cgroup {
289         unsigned short          id;
290 };
291 #define SC_PER_PAGE     (PAGE_SIZE/sizeof(struct swap_cgroup))
292 #define SC_POS_MASK     (SC_PER_PAGE - 1)
293
294 /*
295  * SwapCgroup implements "lookup" and "exchange" operations.
296  * In typical usage, this swap_cgroup is accessed via memcg's charge/uncharge
297  * against SwapCache. At swap_free(), this is accessed directly from swap.
298  *
299  * This means,
300  *  - we have no race in "exchange" when we're accessed via SwapCache because
301  *    SwapCache(and its swp_entry) is under lock.
302  *  - When called via swap_free(), there is no user of this entry and no race.
303  * Then, we don't need lock around "exchange".
304  *
305  * TODO: we can push these buffers out to HIGHMEM.
306  */
307
308 /*
309  * allocate buffer for swap_cgroup.
310  */
311 static int swap_cgroup_prepare(int type)
312 {
313         struct page *page;
314         struct swap_cgroup_ctrl *ctrl;
315         unsigned long idx, max;
316
317         if (!do_swap_account)
318                 return 0;
319         ctrl = &swap_cgroup_ctrl[type];
320
321         for (idx = 0; idx < ctrl->length; idx++) {
322                 page = alloc_page(GFP_KERNEL | __GFP_ZERO);
323                 if (!page)
324                         goto not_enough_page;
325                 ctrl->map[idx] = page;
326         }
327         return 0;
328 not_enough_page:
329         max = idx;
330         for (idx = 0; idx < max; idx++)
331                 __free_page(ctrl->map[idx]);
332
333         return -ENOMEM;
334 }
335
336 /**
337  * swap_cgroup_record - record mem_cgroup for this swp_entry.
338  * @ent: swap entry to be recorded into
339  * @mem: mem_cgroup to be recorded
340  *
341  * Returns old value at success, 0 at failure.
342  * (Of course, old value can be 0.)
343  */
344 unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)
345 {
346         int type = swp_type(ent);
347         unsigned long offset = swp_offset(ent);
348         unsigned long idx = offset / SC_PER_PAGE;
349         unsigned long pos = offset & SC_POS_MASK;
350         struct swap_cgroup_ctrl *ctrl;
351         struct page *mappage;
352         struct swap_cgroup *sc;
353         unsigned short old;
354
355         if (!do_swap_account)
356                 return 0;
357
358         ctrl = &swap_cgroup_ctrl[type];
359
360         mappage = ctrl->map[idx];
361         sc = page_address(mappage);
362         sc += pos;
363         old = sc->id;
364         sc->id = id;
365
366         return old;
367 }
368
369 /**
370  * lookup_swap_cgroup - lookup mem_cgroup tied to swap entry
371  * @ent: swap entry to be looked up.
372  *
373  * Returns CSS ID of mem_cgroup at success. 0 at failure. (0 is invalid ID)
374  */
375 unsigned short lookup_swap_cgroup(swp_entry_t ent)
376 {
377         int type = swp_type(ent);
378         unsigned long offset = swp_offset(ent);
379         unsigned long idx = offset / SC_PER_PAGE;
380         unsigned long pos = offset & SC_POS_MASK;
381         struct swap_cgroup_ctrl *ctrl;
382         struct page *mappage;
383         struct swap_cgroup *sc;
384         unsigned short ret;
385
386         if (!do_swap_account)
387                 return 0;
388
389         ctrl = &swap_cgroup_ctrl[type];
390         mappage = ctrl->map[idx];
391         sc = page_address(mappage);
392         sc += pos;
393         ret = sc->id;
394         return ret;
395 }
396
397 int swap_cgroup_swapon(int type, unsigned long max_pages)
398 {
399         void *array;
400         unsigned long array_size;
401         unsigned long length;
402         struct swap_cgroup_ctrl *ctrl;
403
404         if (!do_swap_account)
405                 return 0;
406
407         length = ((max_pages/SC_PER_PAGE) + 1);
408         array_size = length * sizeof(void *);
409
410         array = vmalloc(array_size);
411         if (!array)
412                 goto nomem;
413
414         memset(array, 0, array_size);
415         ctrl = &swap_cgroup_ctrl[type];
416         mutex_lock(&swap_cgroup_mutex);
417         ctrl->length = length;
418         ctrl->map = array;
419         if (swap_cgroup_prepare(type)) {
420                 /* memory shortage */
421                 ctrl->map = NULL;
422                 ctrl->length = 0;
423                 vfree(array);
424                 mutex_unlock(&swap_cgroup_mutex);
425                 goto nomem;
426         }
427         mutex_unlock(&swap_cgroup_mutex);
428
429         return 0;
430 nomem:
431         printk(KERN_INFO "couldn't allocate enough memory for swap_cgroup.\n");
432         printk(KERN_INFO
433                 "swap_cgroup can be disabled by noswapaccount boot option\n");
434         return -ENOMEM;
435 }
436
437 void swap_cgroup_swapoff(int type)
438 {
439         int i;
440         struct swap_cgroup_ctrl *ctrl;
441
442         if (!do_swap_account)
443                 return;
444
445         mutex_lock(&swap_cgroup_mutex);
446         ctrl = &swap_cgroup_ctrl[type];
447         if (ctrl->map) {
448                 for (i = 0; i < ctrl->length; i++) {
449                         struct page *page = ctrl->map[i];
450                         if (page)
451                                 __free_page(page);
452                 }
453                 vfree(ctrl->map);
454                 ctrl->map = NULL;
455                 ctrl->length = 0;
456         }
457         mutex_unlock(&swap_cgroup_mutex);
458 }
459
460 #endif