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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/mm/oom_kill.c
3 *
4 * Copyright (C) 1998,2000 Rik van Riel
5 * Thanks go out to Claus Fischer for some serious inspiration and
6 * for goading me into coding this file...
David Rientjesa63d83f2010-08-09 17:19:46 -07007 * Copyright (C) 2010 Google, Inc.
8 * Rewritten by David Rientjes
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 *
10 * The routines in this file are used to kill a process when
Paul Jacksona49335c2005-09-06 15:18:09 -070011 * we're seriously out of memory. This gets called from __alloc_pages()
12 * in mm/page_alloc.c when we really run out of memory.
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 *
14 * Since we won't call these routines often (on a well-configured
15 * machine) this file will double as a 'coding guide' and a signpost
16 * for newbie kernel hackers. It features several pointers to major
17 * kernel subsystems and hints as to where to find out what things do.
18 */
19
Alexey Dobriyan8ac773b2006-10-19 23:28:32 -070020#include <linux/oom.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/mm.h>
Alexey Dobriyan4e950f62007-07-30 02:36:13 +040022#include <linux/err.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090023#include <linux/gfp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/sched.h>
25#include <linux/swap.h>
26#include <linux/timex.h>
27#include <linux/jiffies.h>
Paul Jacksonef08e3b2005-09-06 15:18:13 -070028#include <linux/cpuset.h>
Paul Gortmakerb95f1b312011-10-16 02:01:52 -040029#include <linux/export.h>
Martin Schwidefsky8bc719d2006-09-25 23:31:20 -070030#include <linux/notifier.h>
Pavel Emelianovc7ba5c92008-02-07 00:13:58 -080031#include <linux/memcontrol.h>
David Rientjes6f48d0eb2010-08-09 17:18:52 -070032#include <linux/mempolicy.h>
David Howells5cd9c582008-08-14 11:37:28 +010033#include <linux/security.h>
David Rientjesedd45542011-03-22 16:30:12 -070034#include <linux/ptrace.h>
David Rientjesf660daa2011-10-31 17:07:07 -070035#include <linux/freezer.h>
KAMEZAWA Hiroyuki43d2b112012-01-10 15:08:09 -080036#include <linux/ftrace.h>
David Rientjesdc3f21e2012-03-21 16:33:47 -070037#include <linux/ratelimit.h>
KAMEZAWA Hiroyuki43d2b112012-01-10 15:08:09 -080038
39#define CREATE_TRACE_POINTS
40#include <trace/events/oom.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
KAMEZAWA Hiroyukifadd8fb2006-06-23 02:03:13 -070042int sysctl_panic_on_oom;
David Rientjesfe071d72007-10-16 23:25:56 -070043int sysctl_oom_kill_allocating_task;
David Rientjesad915c42010-08-09 17:18:53 -070044int sysctl_oom_dump_tasks = 1;
David Rientjesc7d4cae2009-01-06 14:39:00 -080045static DEFINE_SPINLOCK(zone_scan_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
David Rientjes43362a42011-10-31 17:07:18 -070047/*
48 * compare_swap_oom_score_adj() - compare and swap current's oom_score_adj
49 * @old_val: old oom_score_adj for compare
50 * @new_val: new oom_score_adj for swap
51 *
52 * Sets the oom_score_adj value for current to @new_val iff its present value is
53 * @old_val. Usually used to reinstate a previous value to prevent racing with
54 * userspacing tuning the value in the interim.
55 */
56void compare_swap_oom_score_adj(int old_val, int new_val)
57{
58 struct sighand_struct *sighand = current->sighand;
59
60 spin_lock_irq(&sighand->siglock);
61 if (current->signal->oom_score_adj == old_val)
62 current->signal->oom_score_adj = new_val;
KAMEZAWA Hiroyuki43d2b112012-01-10 15:08:09 -080063 trace_oom_score_adj_update(current);
David Rientjes43362a42011-10-31 17:07:18 -070064 spin_unlock_irq(&sighand->siglock);
65}
66
David Rientjes72788c32011-05-24 17:11:40 -070067/**
68 * test_set_oom_score_adj() - set current's oom_score_adj and return old value
69 * @new_val: new oom_score_adj value
70 *
71 * Sets the oom_score_adj value for current to @new_val with proper
72 * synchronization and returns the old value. Usually used to temporarily
73 * set a value, save the old value in the caller, and then reinstate it later.
74 */
75int test_set_oom_score_adj(int new_val)
76{
77 struct sighand_struct *sighand = current->sighand;
78 int old_val;
79
80 spin_lock_irq(&sighand->siglock);
81 old_val = current->signal->oom_score_adj;
David Rientjesc9f01242011-10-31 17:07:15 -070082 current->signal->oom_score_adj = new_val;
KAMEZAWA Hiroyuki43d2b112012-01-10 15:08:09 -080083 trace_oom_score_adj_update(current);
David Rientjes72788c32011-05-24 17:11:40 -070084 spin_unlock_irq(&sighand->siglock);
85
86 return old_val;
87}
88
David Rientjes6f48d0eb2010-08-09 17:18:52 -070089#ifdef CONFIG_NUMA
90/**
91 * has_intersects_mems_allowed() - check task eligiblity for kill
92 * @tsk: task struct of which task to consider
93 * @mask: nodemask passed to page allocator for mempolicy ooms
94 *
95 * Task eligibility is determined by whether or not a candidate task, @tsk,
96 * shares the same mempolicy nodes as current if it is bound by such a policy
97 * and whether or not it has the same set of allowed cpuset nodes.
KOSAKI Motohiro495789a2009-09-21 17:03:14 -070098 */
David Rientjes6f48d0eb2010-08-09 17:18:52 -070099static bool has_intersects_mems_allowed(struct task_struct *tsk,
100 const nodemask_t *mask)
KOSAKI Motohiro495789a2009-09-21 17:03:14 -0700101{
David Rientjes6f48d0eb2010-08-09 17:18:52 -0700102 struct task_struct *start = tsk;
KOSAKI Motohiro495789a2009-09-21 17:03:14 -0700103
KOSAKI Motohiro495789a2009-09-21 17:03:14 -0700104 do {
David Rientjes6f48d0eb2010-08-09 17:18:52 -0700105 if (mask) {
106 /*
107 * If this is a mempolicy constrained oom, tsk's
108 * cpuset is irrelevant. Only return true if its
109 * mempolicy intersects current, otherwise it may be
110 * needlessly killed.
111 */
112 if (mempolicy_nodemask_intersects(tsk, mask))
113 return true;
114 } else {
115 /*
116 * This is not a mempolicy constrained oom, so only
117 * check the mems of tsk's cpuset.
118 */
119 if (cpuset_mems_allowed_intersects(current, tsk))
120 return true;
121 }
KOSAKI Motohirodf1090a2010-08-09 17:19:39 -0700122 } while_each_thread(start, tsk);
123
David Rientjes6f48d0eb2010-08-09 17:18:52 -0700124 return false;
KOSAKI Motohiro495789a2009-09-21 17:03:14 -0700125}
David Rientjes6f48d0eb2010-08-09 17:18:52 -0700126#else
127static bool has_intersects_mems_allowed(struct task_struct *tsk,
128 const nodemask_t *mask)
129{
130 return true;
131}
132#endif /* CONFIG_NUMA */
KOSAKI Motohiro495789a2009-09-21 17:03:14 -0700133
David Rientjes6f48d0eb2010-08-09 17:18:52 -0700134/*
135 * The process p may have detached its own ->mm while exiting or through
136 * use_mm(), but one or more of its subthreads may still have a valid
137 * pointer. Return p, or any of its subthreads with a valid ->mm, with
138 * task_lock() held.
139 */
KAMEZAWA Hiroyuki158e0a22010-08-10 18:03:00 -0700140struct task_struct *find_lock_task_mm(struct task_struct *p)
Oleg Nesterovdd8e8f42010-08-09 17:18:45 -0700141{
142 struct task_struct *t = p;
143
144 do {
145 task_lock(t);
146 if (likely(t->mm))
147 return t;
148 task_unlock(t);
149 } while_each_thread(p, t);
150
151 return NULL;
152}
153
KOSAKI Motohiroab290ad2010-08-09 17:19:35 -0700154/* return true if the task is not adequate as candidate victim task. */
David Rientjese85bfd32010-09-22 13:05:10 -0700155static bool oom_unkillable_task(struct task_struct *p,
Johannes Weiner72835c82012-01-12 17:18:32 -0800156 const struct mem_cgroup *memcg, const nodemask_t *nodemask)
KOSAKI Motohiroab290ad2010-08-09 17:19:35 -0700157{
158 if (is_global_init(p))
159 return true;
160 if (p->flags & PF_KTHREAD)
161 return true;
162
163 /* When mem_cgroup_out_of_memory() and p is not member of the group */
Johannes Weiner72835c82012-01-12 17:18:32 -0800164 if (memcg && !task_in_mem_cgroup(p, memcg))
KOSAKI Motohiroab290ad2010-08-09 17:19:35 -0700165 return true;
166
167 /* p may not have freeable memory in nodemask */
168 if (!has_intersects_mems_allowed(p, nodemask))
169 return true;
170
171 return false;
172}
173
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174/**
David Rientjesa63d83f2010-08-09 17:19:46 -0700175 * oom_badness - heuristic function to determine which candidate task to kill
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 * @p: task struct of which task we should calculate
David Rientjesa63d83f2010-08-09 17:19:46 -0700177 * @totalpages: total present RAM allowed for page allocation
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 *
David Rientjesa63d83f2010-08-09 17:19:46 -0700179 * The heuristic for determining which task to kill is made to be as simple and
180 * predictable as possible. The goal is to return the highest value for the
181 * task consuming the most memory to avoid subsequent oom failures.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 */
David Rientjesa7f638f2012-05-29 15:06:47 -0700183unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg,
184 const nodemask_t *nodemask, unsigned long totalpages)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185{
David Rientjes1e11ad82012-06-08 13:21:26 -0700186 long points;
David Rientjes61eafb02012-06-20 12:52:58 -0700187 long adj;
KOSAKI Motohiro28b83c52009-09-21 17:03:13 -0700188
Johannes Weiner72835c82012-01-12 17:18:32 -0800189 if (oom_unkillable_task(p, memcg, nodemask))
KOSAKI Motohiro26ebc982010-08-09 17:19:37 -0700190 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191
Oleg Nesterovdd8e8f42010-08-09 17:18:45 -0700192 p = find_lock_task_mm(p);
193 if (!p)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 return 0;
195
David Rientjes61eafb02012-06-20 12:52:58 -0700196 adj = p->signal->oom_score_adj;
197 if (adj == OOM_SCORE_ADJ_MIN) {
Michal Hocko5aecc852011-11-15 14:36:07 -0800198 task_unlock(p);
199 return 0;
200 }
201
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 /*
David Rientjesa63d83f2010-08-09 17:19:46 -0700203 * The baseline for the badness score is the proportion of RAM that each
KOSAKI Motohirof755a042011-04-27 15:26:50 -0700204 * task's rss, pagetable and swap space use.
David Rientjesa63d83f2010-08-09 17:19:46 -0700205 */
David Rientjesa7f638f2012-05-29 15:06:47 -0700206 points = get_mm_rss(p->mm) + p->mm->nr_ptes +
207 get_mm_counter(p->mm, MM_SWAPENTS);
Andrew Morton97c2c9b82006-04-18 22:20:38 -0700208 task_unlock(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209
210 /*
David Rientjesa63d83f2010-08-09 17:19:46 -0700211 * Root processes get 3% bonus, just like the __vm_enough_memory()
212 * implementation used by LSMs.
Hugh Dickins7ba34852007-01-05 16:37:03 -0800213 */
David Rientjesa63d83f2010-08-09 17:19:46 -0700214 if (has_capability_noaudit(p, CAP_SYS_ADMIN))
David Rientjes61eafb02012-06-20 12:52:58 -0700215 adj -= 30;
Hugh Dickins7ba34852007-01-05 16:37:03 -0800216
David Rientjes61eafb02012-06-20 12:52:58 -0700217 /* Normalize to oom_score_adj units */
218 adj *= totalpages / 1000;
219 points += adj;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220
David Rientjesf19e8aa2010-09-22 13:04:52 -0700221 /*
David Rientjesa7f638f2012-05-29 15:06:47 -0700222 * Never return 0 for an eligible task regardless of the root bonus and
223 * oom_score_adj (oom_score_adj can't be OOM_SCORE_ADJ_MIN here).
David Rientjesf19e8aa2010-09-22 13:04:52 -0700224 */
David Rientjes1e11ad82012-06-08 13:21:26 -0700225 return points > 0 ? points : 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226}
227
228/*
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800229 * Determine the type of allocation constraint.
230 */
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800231#ifdef CONFIG_NUMA
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800232static enum oom_constraint constrained_alloc(struct zonelist *zonelist,
David Rientjesa63d83f2010-08-09 17:19:46 -0700233 gfp_t gfp_mask, nodemask_t *nodemask,
234 unsigned long *totalpages)
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800235{
Mel Gorman54a6eb52008-04-28 02:12:16 -0700236 struct zone *zone;
Mel Gormandd1a2392008-04-28 02:12:17 -0700237 struct zoneref *z;
Mel Gorman54a6eb52008-04-28 02:12:16 -0700238 enum zone_type high_zoneidx = gfp_zone(gfp_mask);
David Rientjesa63d83f2010-08-09 17:19:46 -0700239 bool cpuset_limited = false;
240 int nid;
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800241
David Rientjesa63d83f2010-08-09 17:19:46 -0700242 /* Default to all available memory */
243 *totalpages = totalram_pages + total_swap_pages;
244
245 if (!zonelist)
246 return CONSTRAINT_NONE;
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800247 /*
248 * Reach here only when __GFP_NOFAIL is used. So, we should avoid
249 * to kill current.We have to random task kill in this case.
250 * Hopefully, CONSTRAINT_THISNODE...but no way to handle it, now.
251 */
252 if (gfp_mask & __GFP_THISNODE)
253 return CONSTRAINT_NONE;
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800254
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800255 /*
David Rientjesa63d83f2010-08-09 17:19:46 -0700256 * This is not a __GFP_THISNODE allocation, so a truncated nodemask in
257 * the page allocator means a mempolicy is in effect. Cpuset policy
258 * is enforced in get_page_from_freelist().
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800259 */
David Rientjesa63d83f2010-08-09 17:19:46 -0700260 if (nodemask && !nodes_subset(node_states[N_HIGH_MEMORY], *nodemask)) {
261 *totalpages = total_swap_pages;
262 for_each_node_mask(nid, *nodemask)
263 *totalpages += node_spanned_pages(nid);
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800264 return CONSTRAINT_MEMORY_POLICY;
David Rientjesa63d83f2010-08-09 17:19:46 -0700265 }
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800266
267 /* Check this allocation failure is caused by cpuset's wall function */
268 for_each_zone_zonelist_nodemask(zone, z, zonelist,
269 high_zoneidx, nodemask)
270 if (!cpuset_zone_allowed_softwall(zone, gfp_mask))
David Rientjesa63d83f2010-08-09 17:19:46 -0700271 cpuset_limited = true;
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800272
David Rientjesa63d83f2010-08-09 17:19:46 -0700273 if (cpuset_limited) {
274 *totalpages = total_swap_pages;
275 for_each_node_mask(nid, cpuset_current_mems_allowed)
276 *totalpages += node_spanned_pages(nid);
277 return CONSTRAINT_CPUSET;
278 }
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800279 return CONSTRAINT_NONE;
280}
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800281#else
282static enum oom_constraint constrained_alloc(struct zonelist *zonelist,
David Rientjesa63d83f2010-08-09 17:19:46 -0700283 gfp_t gfp_mask, nodemask_t *nodemask,
284 unsigned long *totalpages)
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800285{
David Rientjesa63d83f2010-08-09 17:19:46 -0700286 *totalpages = totalram_pages + total_swap_pages;
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800287 return CONSTRAINT_NONE;
288}
289#endif
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800290
David Rientjes9cbb78b2012-07-31 16:43:44 -0700291enum oom_scan_t oom_scan_process_thread(struct task_struct *task,
292 unsigned long totalpages, const nodemask_t *nodemask,
293 bool force_kill)
David Rientjes462607e2012-07-31 16:43:40 -0700294{
295 if (task->exit_state)
296 return OOM_SCAN_CONTINUE;
David Rientjes9cbb78b2012-07-31 16:43:44 -0700297 if (oom_unkillable_task(task, NULL, nodemask))
David Rientjes462607e2012-07-31 16:43:40 -0700298 return OOM_SCAN_CONTINUE;
299
300 /*
301 * This task already has access to memory reserves and is being killed.
302 * Don't allow any other task to have access to the reserves.
303 */
304 if (test_tsk_thread_flag(task, TIF_MEMDIE)) {
305 if (unlikely(frozen(task)))
306 __thaw_task(task);
307 if (!force_kill)
308 return OOM_SCAN_ABORT;
309 }
310 if (!task->mm)
311 return OOM_SCAN_CONTINUE;
312
313 if (task->flags & PF_EXITING) {
314 /*
315 * If task is current and is in the process of releasing memory,
316 * allow the "kill" to set TIF_MEMDIE, which will allow it to
317 * access memory reserves. Otherwise, it may stall forever.
318 *
319 * The iteration isn't broken here, however, in case other
320 * threads are found to have already been oom killed.
321 */
322 if (task == current)
323 return OOM_SCAN_SELECT;
324 else if (!force_kill) {
325 /*
326 * If this task is not being ptraced on exit, then wait
327 * for it to finish before killing some other task
328 * unnecessarily.
329 */
330 if (!(task->group_leader->ptrace & PT_TRACE_EXIT))
331 return OOM_SCAN_ABORT;
332 }
333 }
334 return OOM_SCAN_OK;
335}
336
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800337/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 * Simple selection loop. We chose the process with the highest
David Rientjes6b0c81b2012-07-31 16:43:45 -0700339 * number of 'points'.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 *
341 * (not docbooked, we don't want this one cluttering up the manual)
342 */
David Rientjesa63d83f2010-08-09 17:19:46 -0700343static struct task_struct *select_bad_process(unsigned int *ppoints,
David Rientjes9cbb78b2012-07-31 16:43:44 -0700344 unsigned long totalpages, const nodemask_t *nodemask,
345 bool force_kill)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346{
David Rientjes3a5dda72011-03-22 16:30:09 -0700347 struct task_struct *g, *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 struct task_struct *chosen = NULL;
David Rientjesa7f638f2012-05-29 15:06:47 -0700349 unsigned long chosen_points = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350
David Rientjes6b0c81b2012-07-31 16:43:45 -0700351 rcu_read_lock();
David Rientjes3a5dda72011-03-22 16:30:09 -0700352 do_each_thread(g, p) {
David Rientjesa63d83f2010-08-09 17:19:46 -0700353 unsigned int points;
Paul Jacksona49335c2005-09-06 15:18:09 -0700354
David Rientjes9cbb78b2012-07-31 16:43:44 -0700355 switch (oom_scan_process_thread(p, totalpages, nodemask,
David Rientjes462607e2012-07-31 16:43:40 -0700356 force_kill)) {
357 case OOM_SCAN_SELECT:
358 chosen = p;
359 chosen_points = ULONG_MAX;
360 /* fall through */
361 case OOM_SCAN_CONTINUE:
Andrey Vagin30e2b412011-03-22 16:30:11 -0700362 continue;
David Rientjes462607e2012-07-31 16:43:40 -0700363 case OOM_SCAN_ABORT:
David Rientjes6b0c81b2012-07-31 16:43:45 -0700364 rcu_read_unlock();
David Rientjes462607e2012-07-31 16:43:40 -0700365 return ERR_PTR(-1UL);
366 case OOM_SCAN_OK:
367 break;
368 };
David Rientjes9cbb78b2012-07-31 16:43:44 -0700369 points = oom_badness(p, NULL, nodemask, totalpages);
David Rientjesa7f638f2012-05-29 15:06:47 -0700370 if (points > chosen_points) {
Paul Jacksona49335c2005-09-06 15:18:09 -0700371 chosen = p;
David Rientjesa7f638f2012-05-29 15:06:47 -0700372 chosen_points = points;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373 }
David Rientjes3a5dda72011-03-22 16:30:09 -0700374 } while_each_thread(g, p);
David Rientjes6b0c81b2012-07-31 16:43:45 -0700375 if (chosen)
376 get_task_struct(chosen);
377 rcu_read_unlock();
Oleg Nesterov972c4ea2006-09-29 02:01:12 -0700378
David Rientjesa7f638f2012-05-29 15:06:47 -0700379 *ppoints = chosen_points * 1000 / totalpages;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 return chosen;
381}
382
383/**
Randy Dunlap1b578df2008-03-19 17:00:42 -0700384 * dump_tasks - dump current memory state of all system tasks
Wanpeng Lidad75572012-06-20 12:53:01 -0700385 * @memcg: current's memory controller, if constrained
David Rientjese85bfd32010-09-22 13:05:10 -0700386 * @nodemask: nodemask passed to page allocator for mempolicy ooms
Randy Dunlap1b578df2008-03-19 17:00:42 -0700387 *
David Rientjese85bfd32010-09-22 13:05:10 -0700388 * Dumps the current memory state of all eligible tasks. Tasks not in the same
389 * memcg, not in the same cpuset, or bound to a disjoint set of mempolicy nodes
390 * are not shown.
David Rientjesde34d962012-07-31 16:42:56 -0700391 * State information includes task's pid, uid, tgid, vm size, rss, nr_ptes,
392 * swapents, oom_score_adj value, and name.
David Rientjesfef1bdd2008-02-07 00:14:07 -0800393 */
Johannes Weiner72835c82012-01-12 17:18:32 -0800394static void dump_tasks(const struct mem_cgroup *memcg, const nodemask_t *nodemask)
David Rientjesfef1bdd2008-02-07 00:14:07 -0800395{
KOSAKI Motohiroc55db952010-08-09 17:18:46 -0700396 struct task_struct *p;
397 struct task_struct *task;
David Rientjesfef1bdd2008-02-07 00:14:07 -0800398
David Rientjesde34d962012-07-31 16:42:56 -0700399 pr_info("[ pid ] uid tgid total_vm rss nr_ptes swapents oom_score_adj name\n");
David Rientjes6b0c81b2012-07-31 16:43:45 -0700400 rcu_read_lock();
KOSAKI Motohiroc55db952010-08-09 17:18:46 -0700401 for_each_process(p) {
Johannes Weiner72835c82012-01-12 17:18:32 -0800402 if (oom_unkillable_task(p, memcg, nodemask))
David Rientjesfef1bdd2008-02-07 00:14:07 -0800403 continue;
404
KOSAKI Motohiroc55db952010-08-09 17:18:46 -0700405 task = find_lock_task_mm(p);
406 if (!task) {
David Rientjes6d2661e2009-05-28 14:34:19 -0700407 /*
David Rientjes74ab7f12010-08-09 17:18:46 -0700408 * This is a kthread or all of p's threads have already
409 * detached their mm's. There's no need to report
KOSAKI Motohiroc55db952010-08-09 17:18:46 -0700410 * them; they can't be oom killed anyway.
David Rientjes6d2661e2009-05-28 14:34:19 -0700411 */
David Rientjes6d2661e2009-05-28 14:34:19 -0700412 continue;
413 }
KOSAKI Motohiroc55db952010-08-09 17:18:46 -0700414
David Rientjesde34d962012-07-31 16:42:56 -0700415 pr_info("[%5d] %5d %5d %8lu %8lu %7lu %8lu %5d %s\n",
Eric W. Biederman078de5f2012-02-08 07:00:08 -0800416 task->pid, from_kuid(&init_user_ns, task_uid(task)),
417 task->tgid, task->mm->total_vm, get_mm_rss(task->mm),
David Rientjesde34d962012-07-31 16:42:56 -0700418 task->mm->nr_ptes,
419 get_mm_counter(task->mm, MM_SWAPENTS),
David Rientjesa63d83f2010-08-09 17:19:46 -0700420 task->signal->oom_score_adj, task->comm);
KOSAKI Motohiroc55db952010-08-09 17:18:46 -0700421 task_unlock(task);
422 }
David Rientjes6b0c81b2012-07-31 16:43:45 -0700423 rcu_read_unlock();
David Rientjesfef1bdd2008-02-07 00:14:07 -0800424}
425
Daisuke Nishimurad31f56d2009-12-15 16:47:12 -0800426static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order,
Johannes Weiner72835c82012-01-12 17:18:32 -0800427 struct mem_cgroup *memcg, const nodemask_t *nodemask)
David Rientjes1b604d72009-12-14 17:57:47 -0800428{
David Rientjes5e9d8342010-08-09 17:18:51 -0700429 task_lock(current);
David Rientjes1b604d72009-12-14 17:57:47 -0800430 pr_warning("%s invoked oom-killer: gfp_mask=0x%x, order=%d, "
Davidlohr Bueso01dc52e2012-10-08 16:29:30 -0700431 "oom_score_adj=%d\n",
432 current->comm, gfp_mask, order,
David Rientjesa63d83f2010-08-09 17:19:46 -0700433 current->signal->oom_score_adj);
David Rientjes1b604d72009-12-14 17:57:47 -0800434 cpuset_print_task_mems_allowed(current);
435 task_unlock(current);
436 dump_stack();
Johannes Weiner72835c82012-01-12 17:18:32 -0800437 mem_cgroup_print_oom_info(memcg, p);
David Rientjesb2b755b2011-03-24 15:18:15 -0700438 show_mem(SHOW_MEM_FILTER_NODES);
David Rientjes1b604d72009-12-14 17:57:47 -0800439 if (sysctl_oom_dump_tasks)
Johannes Weiner72835c82012-01-12 17:18:32 -0800440 dump_tasks(memcg, nodemask);
David Rientjes1b604d72009-12-14 17:57:47 -0800441}
442
KOSAKI Motohiro3b4798c2009-12-15 16:45:32 -0800443#define K(x) ((x) << (PAGE_SHIFT-10))
David Rientjes6b0c81b2012-07-31 16:43:45 -0700444/*
445 * Must be called while holding a reference to p, which will be released upon
446 * returning.
447 */
David Rientjes9cbb78b2012-07-31 16:43:44 -0700448void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
449 unsigned int points, unsigned long totalpages,
450 struct mem_cgroup *memcg, nodemask_t *nodemask,
451 const char *message)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452{
Linus Torvalds52d3c032011-03-14 15:17:07 -0700453 struct task_struct *victim = p;
David Rientjes5e9d8342010-08-09 17:18:51 -0700454 struct task_struct *child;
Linus Torvalds52d3c032011-03-14 15:17:07 -0700455 struct task_struct *t = p;
David Rientjes647f2bd2012-03-21 16:33:46 -0700456 struct mm_struct *mm;
Linus Torvalds52d3c032011-03-14 15:17:07 -0700457 unsigned int victim_points = 0;
David Rientjesdc3f21e2012-03-21 16:33:47 -0700458 static DEFINE_RATELIMIT_STATE(oom_rs, DEFAULT_RATELIMIT_INTERVAL,
459 DEFAULT_RATELIMIT_BURST);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460
Nick Piggin50ec3bb2006-09-25 23:31:29 -0700461 /*
462 * If the task is already exiting, don't alarm the sysadmin or kill
463 * its children or threads, just set TIF_MEMDIE so it can die quickly
464 */
KOSAKI Motohiro0753ba02009-08-18 14:11:10 -0700465 if (p->flags & PF_EXITING) {
David Rientjes43589972010-08-09 17:18:49 -0700466 set_tsk_thread_flag(p, TIF_MEMDIE);
David Rientjes6b0c81b2012-07-31 16:43:45 -0700467 put_task_struct(p);
David Rientjes2a1c9b12012-03-21 16:33:46 -0700468 return;
Nick Piggin50ec3bb2006-09-25 23:31:29 -0700469 }
470
David Rientjesdc3f21e2012-03-21 16:33:47 -0700471 if (__ratelimit(&oom_rs))
David Rientjes8447d952012-03-21 16:33:47 -0700472 dump_header(p, gfp_mask, order, memcg, nodemask);
473
David Rientjes5e9d8342010-08-09 17:18:51 -0700474 task_lock(p);
David Rientjesa63d83f2010-08-09 17:19:46 -0700475 pr_err("%s: Kill process %d (%s) score %d or sacrifice child\n",
David Rientjes5e9d8342010-08-09 17:18:51 -0700476 message, task_pid_nr(p), p->comm, points);
477 task_unlock(p);
Nick Pigginf3af38d2006-12-06 20:31:51 -0800478
David Rientjes5e9d8342010-08-09 17:18:51 -0700479 /*
480 * If any of p's children has a different mm and is eligible for kill,
David Rientjes11239832011-07-25 17:12:17 -0700481 * the one with the highest oom_badness() score is sacrificed for its
David Rientjes5e9d8342010-08-09 17:18:51 -0700482 * parent. This attempts to lose the minimal amount of work done while
483 * still freeing memory.
484 */
David Rientjes6b0c81b2012-07-31 16:43:45 -0700485 read_lock(&tasklist_lock);
Oleg Nesterovdd8e8f42010-08-09 17:18:45 -0700486 do {
David Rientjes5e9d8342010-08-09 17:18:51 -0700487 list_for_each_entry(child, &t->children, sibling) {
David Rientjesa63d83f2010-08-09 17:19:46 -0700488 unsigned int child_points;
David Rientjes5e9d8342010-08-09 17:18:51 -0700489
David Rientjesedd45542011-03-22 16:30:12 -0700490 if (child->mm == p->mm)
491 continue;
David Rientjesa63d83f2010-08-09 17:19:46 -0700492 /*
493 * oom_badness() returns 0 if the thread is unkillable
494 */
Johannes Weiner72835c82012-01-12 17:18:32 -0800495 child_points = oom_badness(child, memcg, nodemask,
David Rientjesa63d83f2010-08-09 17:19:46 -0700496 totalpages);
David Rientjes5e9d8342010-08-09 17:18:51 -0700497 if (child_points > victim_points) {
David Rientjes6b0c81b2012-07-31 16:43:45 -0700498 put_task_struct(victim);
David Rientjes5e9d8342010-08-09 17:18:51 -0700499 victim = child;
500 victim_points = child_points;
David Rientjes6b0c81b2012-07-31 16:43:45 -0700501 get_task_struct(victim);
David Rientjes5e9d8342010-08-09 17:18:51 -0700502 }
Oleg Nesterovdd8e8f42010-08-09 17:18:45 -0700503 }
504 } while_each_thread(p, t);
David Rientjes6b0c81b2012-07-31 16:43:45 -0700505 read_unlock(&tasklist_lock);
Oleg Nesterovdd8e8f42010-08-09 17:18:45 -0700506
David Rientjes6b0c81b2012-07-31 16:43:45 -0700507 rcu_read_lock();
508 p = find_lock_task_mm(victim);
509 if (!p) {
510 rcu_read_unlock();
511 put_task_struct(victim);
David Rientjes647f2bd2012-03-21 16:33:46 -0700512 return;
David Rientjes6b0c81b2012-07-31 16:43:45 -0700513 } else if (victim != p) {
514 get_task_struct(p);
515 put_task_struct(victim);
516 victim = p;
517 }
David Rientjes647f2bd2012-03-21 16:33:46 -0700518
519 /* mm cannot safely be dereferenced after task_unlock(victim) */
520 mm = victim->mm;
521 pr_err("Killed process %d (%s) total-vm:%lukB, anon-rss:%lukB, file-rss:%lukB\n",
522 task_pid_nr(victim), victim->comm, K(victim->mm->total_vm),
523 K(get_mm_counter(victim->mm, MM_ANONPAGES)),
524 K(get_mm_counter(victim->mm, MM_FILEPAGES)));
525 task_unlock(victim);
526
527 /*
528 * Kill all user processes sharing victim->mm in other thread groups, if
529 * any. They don't get access to memory reserves, though, to avoid
530 * depletion of all memory. This prevents mm->mmap_sem livelock when an
531 * oom killed thread cannot exit because it requires the semaphore and
532 * its contended by another thread trying to allocate memory itself.
533 * That thread will now get access to memory reserves since it has a
534 * pending fatal signal.
535 */
536 for_each_process(p)
537 if (p->mm == mm && !same_thread_group(p, victim) &&
538 !(p->flags & PF_KTHREAD)) {
539 if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
540 continue;
541
542 task_lock(p); /* Protect ->comm from prctl() */
543 pr_err("Kill process %d (%s) sharing same memory\n",
544 task_pid_nr(p), p->comm);
545 task_unlock(p);
Oleg Nesterovd2d39302012-03-23 15:02:45 -0700546 do_send_sig_info(SIGKILL, SEND_SIG_FORCED, p, true);
David Rientjes647f2bd2012-03-21 16:33:46 -0700547 }
David Rientjes6b0c81b2012-07-31 16:43:45 -0700548 rcu_read_unlock();
David Rientjes647f2bd2012-03-21 16:33:46 -0700549
550 set_tsk_thread_flag(victim, TIF_MEMDIE);
Oleg Nesterovd2d39302012-03-23 15:02:45 -0700551 do_send_sig_info(SIGKILL, SEND_SIG_FORCED, victim, true);
David Rientjes6b0c81b2012-07-31 16:43:45 -0700552 put_task_struct(victim);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553}
David Rientjes647f2bd2012-03-21 16:33:46 -0700554#undef K
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555
David Rientjes309ed882010-08-09 17:18:54 -0700556/*
557 * Determines whether the kernel must panic because of the panic_on_oom sysctl.
558 */
David Rientjes876aafb2012-07-31 16:43:48 -0700559void check_panic_on_oom(enum oom_constraint constraint, gfp_t gfp_mask,
560 int order, const nodemask_t *nodemask)
David Rientjes309ed882010-08-09 17:18:54 -0700561{
562 if (likely(!sysctl_panic_on_oom))
563 return;
564 if (sysctl_panic_on_oom != 2) {
565 /*
566 * panic_on_oom == 1 only affects CONSTRAINT_NONE, the kernel
567 * does not panic for cpuset, mempolicy, or memcg allocation
568 * failures.
569 */
570 if (constraint != CONSTRAINT_NONE)
571 return;
572 }
David Rientjese85bfd32010-09-22 13:05:10 -0700573 dump_header(NULL, gfp_mask, order, NULL, nodemask);
David Rientjes309ed882010-08-09 17:18:54 -0700574 panic("Out of memory: %s panic_on_oom is enabled\n",
575 sysctl_panic_on_oom == 2 ? "compulsory" : "system-wide");
576}
577
Martin Schwidefsky8bc719d2006-09-25 23:31:20 -0700578static BLOCKING_NOTIFIER_HEAD(oom_notify_list);
579
580int register_oom_notifier(struct notifier_block *nb)
581{
582 return blocking_notifier_chain_register(&oom_notify_list, nb);
583}
584EXPORT_SYMBOL_GPL(register_oom_notifier);
585
586int unregister_oom_notifier(struct notifier_block *nb)
587{
588 return blocking_notifier_chain_unregister(&oom_notify_list, nb);
589}
590EXPORT_SYMBOL_GPL(unregister_oom_notifier);
591
David Rientjes098d7f12007-10-16 23:25:55 -0700592/*
593 * Try to acquire the OOM killer lock for the zones in zonelist. Returns zero
594 * if a parallel OOM killing is already taking place that includes a zone in
595 * the zonelist. Otherwise, locks all zones in the zonelist and returns 1.
596 */
Minchan Kimff321fe2010-08-09 17:18:57 -0700597int try_set_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_mask)
David Rientjes098d7f12007-10-16 23:25:55 -0700598{
Mel Gormandd1a2392008-04-28 02:12:17 -0700599 struct zoneref *z;
600 struct zone *zone;
David Rientjes098d7f12007-10-16 23:25:55 -0700601 int ret = 1;
602
David Rientjesc7d4cae2009-01-06 14:39:00 -0800603 spin_lock(&zone_scan_lock);
Mel Gormandd1a2392008-04-28 02:12:17 -0700604 for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) {
605 if (zone_is_oom_locked(zone)) {
David Rientjes098d7f12007-10-16 23:25:55 -0700606 ret = 0;
607 goto out;
608 }
Mel Gormandd1a2392008-04-28 02:12:17 -0700609 }
David Rientjes098d7f12007-10-16 23:25:55 -0700610
Mel Gormandd1a2392008-04-28 02:12:17 -0700611 for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) {
612 /*
David Rientjesc7d4cae2009-01-06 14:39:00 -0800613 * Lock each zone in the zonelist under zone_scan_lock so a
Minchan Kimff321fe2010-08-09 17:18:57 -0700614 * parallel invocation of try_set_zonelist_oom() doesn't succeed
Mel Gormandd1a2392008-04-28 02:12:17 -0700615 * when it shouldn't.
616 */
617 zone_set_flag(zone, ZONE_OOM_LOCKED);
618 }
619
David Rientjes098d7f12007-10-16 23:25:55 -0700620out:
David Rientjesc7d4cae2009-01-06 14:39:00 -0800621 spin_unlock(&zone_scan_lock);
David Rientjes098d7f12007-10-16 23:25:55 -0700622 return ret;
623}
624
625/*
626 * Clears the ZONE_OOM_LOCKED flag for all zones in the zonelist so that failed
627 * allocation attempts with zonelists containing them may now recall the OOM
628 * killer, if necessary.
629 */
Mel Gormandd1a2392008-04-28 02:12:17 -0700630void clear_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_mask)
David Rientjes098d7f12007-10-16 23:25:55 -0700631{
Mel Gormandd1a2392008-04-28 02:12:17 -0700632 struct zoneref *z;
633 struct zone *zone;
David Rientjes098d7f12007-10-16 23:25:55 -0700634
David Rientjesc7d4cae2009-01-06 14:39:00 -0800635 spin_lock(&zone_scan_lock);
Mel Gormandd1a2392008-04-28 02:12:17 -0700636 for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) {
637 zone_clear_flag(zone, ZONE_OOM_LOCKED);
638 }
David Rientjesc7d4cae2009-01-06 14:39:00 -0800639 spin_unlock(&zone_scan_lock);
David Rientjes098d7f12007-10-16 23:25:55 -0700640}
641
Nick Piggin1c0fe6e2009-01-06 14:38:59 -0800642/*
David Rientjese3658932010-08-09 17:18:55 -0700643 * Try to acquire the oom killer lock for all system zones. Returns zero if a
644 * parallel oom killing is taking place, otherwise locks all zones and returns
645 * non-zero.
646 */
647static int try_set_system_oom(void)
648{
649 struct zone *zone;
650 int ret = 1;
651
652 spin_lock(&zone_scan_lock);
653 for_each_populated_zone(zone)
654 if (zone_is_oom_locked(zone)) {
655 ret = 0;
656 goto out;
657 }
658 for_each_populated_zone(zone)
659 zone_set_flag(zone, ZONE_OOM_LOCKED);
660out:
661 spin_unlock(&zone_scan_lock);
662 return ret;
663}
664
665/*
666 * Clears ZONE_OOM_LOCKED for all system zones so that failed allocation
667 * attempts or page faults may now recall the oom killer, if necessary.
668 */
669static void clear_system_oom(void)
670{
671 struct zone *zone;
672
673 spin_lock(&zone_scan_lock);
674 for_each_populated_zone(zone)
675 zone_clear_flag(zone, ZONE_OOM_LOCKED);
676 spin_unlock(&zone_scan_lock);
677}
678
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679/**
Dave Peterson6937a252006-06-23 02:03:13 -0700680 * out_of_memory - kill the "best" process when we run out of memory
Randy Dunlap1b578df2008-03-19 17:00:42 -0700681 * @zonelist: zonelist pointer
682 * @gfp_mask: memory allocation flags
683 * @order: amount of memory being requested as a power of 2
David Rientjes6f48d0eb2010-08-09 17:18:52 -0700684 * @nodemask: nodemask passed to page allocator
David Rientjes08ab9b12012-03-21 16:34:04 -0700685 * @force_kill: true if a task must be killed, even if others are exiting
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 *
687 * If we run out of memory, we have the choice between either
688 * killing a random task (bad), letting the system crash (worse)
689 * OR try to be smart about which process to kill. Note that we
690 * don't have to be perfect here, we just have to be good.
691 */
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -0800692void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask,
David Rientjes08ab9b12012-03-21 16:34:04 -0700693 int order, nodemask_t *nodemask, bool force_kill)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694{
David Rientjese85bfd32010-09-22 13:05:10 -0700695 const nodemask_t *mpol_mask;
David Rientjes0aad4b32010-08-09 17:18:59 -0700696 struct task_struct *p;
David Rientjesa63d83f2010-08-09 17:19:46 -0700697 unsigned long totalpages;
Martin Schwidefsky8bc719d2006-09-25 23:31:20 -0700698 unsigned long freed = 0;
David Rientjes9cbb78b2012-07-31 16:43:44 -0700699 unsigned int uninitialized_var(points);
David Rientjese3658932010-08-09 17:18:55 -0700700 enum oom_constraint constraint = CONSTRAINT_NONE;
KOSAKI Motohirob52723c2010-08-19 14:13:39 -0700701 int killed = 0;
Martin Schwidefsky8bc719d2006-09-25 23:31:20 -0700702
703 blocking_notifier_call_chain(&oom_notify_list, 0, &freed);
704 if (freed > 0)
705 /* Got some memory back in the last second. */
706 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707
David Rientjes7b98c2e2010-08-09 17:18:48 -0700708 /*
709 * If current has a pending SIGKILL, then automatically select it. The
710 * goal is to allow it to allocate so that it may quickly exit and free
711 * its memory.
712 */
713 if (fatal_signal_pending(current)) {
714 set_thread_flag(TIF_MEMDIE);
715 return;
716 }
717
Christoph Lameter9b0f8b02006-02-20 18:27:52 -0800718 /*
719 * Check if there were limitations on the allocation (only relevant for
720 * NUMA) that may require different handling.
721 */
David Rientjesa63d83f2010-08-09 17:19:46 -0700722 constraint = constrained_alloc(zonelist, gfp_mask, nodemask,
723 &totalpages);
David Rientjese85bfd32010-09-22 13:05:10 -0700724 mpol_mask = (constraint == CONSTRAINT_MEMORY_POLICY) ? nodemask : NULL;
725 check_panic_on_oom(constraint, gfp_mask, order, mpol_mask);
David Rientjes0aad4b32010-08-09 17:18:59 -0700726
David Rientjes121d1ba2012-07-31 16:42:55 -0700727 if (sysctl_oom_kill_allocating_task && current->mm &&
KOSAKI Motohiroa96cfd62010-08-09 17:19:38 -0700728 !oom_unkillable_task(current, NULL, nodemask) &&
David Rientjes121d1ba2012-07-31 16:42:55 -0700729 current->signal->oom_score_adj != OOM_SCORE_ADJ_MIN) {
David Rientjes6b0c81b2012-07-31 16:43:45 -0700730 get_task_struct(current);
David Rientjes2a1c9b12012-03-21 16:33:46 -0700731 oom_kill_process(current, gfp_mask, order, 0, totalpages, NULL,
732 nodemask,
733 "Out of memory (oom_kill_allocating_task)");
734 goto out;
David Rientjes0aad4b32010-08-09 17:18:59 -0700735 }
736
David Rientjes9cbb78b2012-07-31 16:43:44 -0700737 p = select_bad_process(&points, totalpages, mpol_mask, force_kill);
David Rientjes0aad4b32010-08-09 17:18:59 -0700738 /* Found nothing?!?! Either we hang forever, or we panic. */
739 if (!p) {
David Rientjese85bfd32010-09-22 13:05:10 -0700740 dump_header(NULL, gfp_mask, order, NULL, mpol_mask);
David Rientjes0aad4b32010-08-09 17:18:59 -0700741 panic("Out of memory and no killable processes...\n");
742 }
David Rientjes2a1c9b12012-03-21 16:33:46 -0700743 if (PTR_ERR(p) != -1UL) {
744 oom_kill_process(p, gfp_mask, order, points, totalpages, NULL,
745 nodemask, "Out of memory");
746 killed = 1;
747 }
KOSAKI Motohirob52723c2010-08-19 14:13:39 -0700748out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749 /*
David Rientjes4f774b92012-07-31 16:42:37 -0700750 * Give the killed threads a good chance of exiting before trying to
751 * allocate memory again.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 */
David Rientjes4f774b92012-07-31 16:42:37 -0700753 if (killed)
754 schedule_timeout_killable(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755}
David Rientjese3658932010-08-09 17:18:55 -0700756
757/*
758 * The pagefault handler calls here because it is out of memory, so kill a
759 * memory-hogging task. If a populated zone has ZONE_OOM_LOCKED set, a parallel
760 * oom killing is already in progress so do nothing. If a task is found with
761 * TIF_MEMDIE set, it has been killed so do nothing and allow it to exit.
762 */
763void pagefault_out_of_memory(void)
764{
765 if (try_set_system_oom()) {
David Rientjes08ab9b12012-03-21 16:34:04 -0700766 out_of_memory(NULL, 0, 0, NULL, false);
David Rientjese3658932010-08-09 17:18:55 -0700767 clear_system_oom();
768 }
David Rientjes4f774b92012-07-31 16:42:37 -0700769 schedule_timeout_killable(1);
David Rientjese3658932010-08-09 17:18:55 -0700770}