memcg: use __GFP_NOWARN in page cgroup allocation
[linux-3.10.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 /*
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  */
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  */
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  */
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
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
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