* Copyright (C) 1998,2000 Rik van Riel
* Thanks go out to Claus Fischer for some serious inspiration and
* for goading me into coding this file...
+ * Copyright (C) 2010 Google, Inc.
+ * Rewritten by David Rientjes
*
* The routines in this file are used to kill a process when
* we're seriously out of memory. This gets called from __alloc_pages()
int sysctl_panic_on_oom;
int sysctl_oom_kill_allocating_task;
-int sysctl_oom_dump_tasks;
+int sysctl_oom_dump_tasks = 1;
static DEFINE_SPINLOCK(zone_scan_lock);
-/* #define DEBUG */
#ifdef CONFIG_NUMA
/**
if (cpuset_mems_allowed_intersects(current, tsk))
return true;
}
- tsk = next_thread(tsk);
- } while (tsk != start);
+ } while_each_thread(start, tsk);
+
return false;
}
#else
}
#endif /* CONFIG_NUMA */
+/*
+ * If this is a system OOM (not a memcg OOM) and the task selected to be
+ * killed is not already running at high (RT) priorities, speed up the
+ * recovery by boosting the dying task to the lowest FIFO priority.
+ * That helps with the recovery and avoids interfering with RT tasks.
+ */
+static void boost_dying_task_prio(struct task_struct *p,
+ struct mem_cgroup *mem)
+{
+ struct sched_param param = { .sched_priority = 1 };
+
+ if (mem)
+ return;
+
+ if (!rt_task(p))
+ sched_setscheduler_nocheck(p, SCHED_FIFO, ¶m);
+}
+
/*
* The process p may have detached its own ->mm while exiting or through
* use_mm(), but one or more of its subthreads may still have a valid
* pointer. Return p, or any of its subthreads with a valid ->mm, with
* task_lock() held.
*/
-static struct task_struct *find_lock_task_mm(struct task_struct *p)
+struct task_struct *find_lock_task_mm(struct task_struct *p)
{
struct task_struct *t = p;
return NULL;
}
+/* return true if the task is not adequate as candidate victim task. */
+static bool oom_unkillable_task(struct task_struct *p, struct mem_cgroup *mem,
+ const nodemask_t *nodemask)
+{
+ if (is_global_init(p))
+ return true;
+ if (p->flags & PF_KTHREAD)
+ return true;
+
+ /* When mem_cgroup_out_of_memory() and p is not member of the group */
+ if (mem && !task_in_mem_cgroup(p, mem))
+ return true;
+
+ /* p may not have freeable memory in nodemask */
+ if (!has_intersects_mems_allowed(p, nodemask))
+ return true;
+
+ return false;
+}
+
/**
- * badness - calculate a numeric value for how bad this task has been
+ * oom_badness - heuristic function to determine which candidate task to kill
* @p: task struct of which task we should calculate
- * @uptime: current uptime in seconds
+ * @totalpages: total present RAM allowed for page allocation
*
- * The formula used is relatively simple and documented inline in the
- * function. The main rationale is that we want to select a good task
- * to kill when we run out of memory.
- *
- * Good in this context means that:
- * 1) we lose the minimum amount of work done
- * 2) we recover a large amount of memory
- * 3) we don't kill anything innocent of eating tons of memory
- * 4) we want to kill the minimum amount of processes (one)
- * 5) we try to kill the process the user expects us to kill, this
- * algorithm has been meticulously tuned to meet the principle
- * of least surprise ... (be careful when you change it)
+ * The heuristic for determining which task to kill is made to be as simple and
+ * predictable as possible. The goal is to return the highest value for the
+ * task consuming the most memory to avoid subsequent oom failures.
*/
-
-unsigned long badness(struct task_struct *p, unsigned long uptime)
+unsigned int oom_badness(struct task_struct *p, struct mem_cgroup *mem,
+ const nodemask_t *nodemask, unsigned long totalpages)
{
- unsigned long points, cpu_time, run_time;
- struct task_struct *child;
- struct task_struct *c, *t;
- int oom_adj = p->signal->oom_adj;
- struct task_cputime task_time;
- unsigned long utime;
- unsigned long stime;
+ int points;
- if (oom_adj == OOM_DISABLE)
+ if (oom_unkillable_task(p, mem, nodemask))
return 0;
p = find_lock_task_mm(p);
return 0;
/*
- * The memory size of the process is the basis for the badness.
- */
- points = p->mm->total_vm;
- task_unlock(p);
-
- /*
- * swapoff can easily use up all memory, so kill those first.
- */
- if (p->flags & PF_OOM_ORIGIN)
- return ULONG_MAX;
-
- /*
- * Processes which fork a lot of child processes are likely
- * a good choice. We add half the vmsize of the children if they
- * have an own mm. This prevents forking servers to flood the
- * machine with an endless amount of children. In case a single
- * child is eating the vast majority of memory, adding only half
- * to the parents will make the child our kill candidate of choice.
+ * Shortcut check for OOM_SCORE_ADJ_MIN so the entire heuristic doesn't
+ * need to be executed for something that cannot be killed.
*/
- t = p;
- do {
- list_for_each_entry(c, &t->children, sibling) {
- child = find_lock_task_mm(c);
- if (child) {
- if (child->mm != p->mm)
- points += child->mm->total_vm/2 + 1;
- task_unlock(child);
- }
- }
- } while_each_thread(p, t);
+ if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) {
+ task_unlock(p);
+ return 0;
+ }
/*
- * CPU time is in tens of seconds and run time is in thousands
- * of seconds. There is no particular reason for this other than
- * that it turned out to work very well in practice.
+ * When the PF_OOM_ORIGIN bit is set, it indicates the task should have
+ * priority for oom killing.
*/
- thread_group_cputime(p, &task_time);
- utime = cputime_to_jiffies(task_time.utime);
- stime = cputime_to_jiffies(task_time.stime);
- cpu_time = (utime + stime) >> (SHIFT_HZ + 3);
-
-
- if (uptime >= p->start_time.tv_sec)
- run_time = (uptime - p->start_time.tv_sec) >> 10;
- else
- run_time = 0;
-
- if (cpu_time)
- points /= int_sqrt(cpu_time);
- if (run_time)
- points /= int_sqrt(int_sqrt(run_time));
+ if (p->flags & PF_OOM_ORIGIN) {
+ task_unlock(p);
+ return 1000;
+ }
/*
- * Niced processes are most likely less important, so double
- * their badness points.
+ * The memory controller may have a limit of 0 bytes, so avoid a divide
+ * by zero, if necessary.
*/
- if (task_nice(p) > 0)
- points *= 2;
+ if (!totalpages)
+ totalpages = 1;
/*
- * Superuser processes are usually more important, so we make it
- * less likely that we kill those.
+ * The baseline for the badness score is the proportion of RAM that each
+ * task's rss and swap space use.
*/
- if (has_capability_noaudit(p, CAP_SYS_ADMIN) ||
- has_capability_noaudit(p, CAP_SYS_RESOURCE))
- points /= 4;
+ points = (get_mm_rss(p->mm) + get_mm_counter(p->mm, MM_SWAPENTS)) * 1000 /
+ totalpages;
+ task_unlock(p);
/*
- * We don't want to kill a process with direct hardware access.
- * Not only could that mess up the hardware, but usually users
- * tend to only have this flag set on applications they think
- * of as important.
+ * Root processes get 3% bonus, just like the __vm_enough_memory()
+ * implementation used by LSMs.
*/
- if (has_capability_noaudit(p, CAP_SYS_RAWIO))
- points /= 4;
+ if (has_capability_noaudit(p, CAP_SYS_ADMIN))
+ points -= 30;
/*
- * Adjust the score by oom_adj.
+ * /proc/pid/oom_score_adj ranges from -1000 to +1000 such that it may
+ * either completely disable oom killing or always prefer a certain
+ * task.
*/
- if (oom_adj) {
- if (oom_adj > 0) {
- if (!points)
- points = 1;
- points <<= oom_adj;
- } else
- points >>= -(oom_adj);
- }
+ points += p->signal->oom_score_adj;
-#ifdef DEBUG
- printk(KERN_DEBUG "OOMkill: task %d (%s) got %lu points\n",
- p->pid, p->comm, points);
-#endif
- return points;
+ if (points < 0)
+ return 0;
+ return (points < 1000) ? points : 1000;
}
/*
*/
#ifdef CONFIG_NUMA
static enum oom_constraint constrained_alloc(struct zonelist *zonelist,
- gfp_t gfp_mask, nodemask_t *nodemask)
+ gfp_t gfp_mask, nodemask_t *nodemask,
+ unsigned long *totalpages)
{
struct zone *zone;
struct zoneref *z;
enum zone_type high_zoneidx = gfp_zone(gfp_mask);
+ bool cpuset_limited = false;
+ int nid;
+ /* Default to all available memory */
+ *totalpages = totalram_pages + total_swap_pages;
+
+ if (!zonelist)
+ return CONSTRAINT_NONE;
/*
* Reach here only when __GFP_NOFAIL is used. So, we should avoid
* to kill current.We have to random task kill in this case.
return CONSTRAINT_NONE;
/*
- * The nodemask here is a nodemask passed to alloc_pages(). Now,
- * cpuset doesn't use this nodemask for its hardwall/softwall/hierarchy
- * feature. mempolicy is an only user of nodemask here.
- * check mempolicy's nodemask contains all N_HIGH_MEMORY
+ * This is not a __GFP_THISNODE allocation, so a truncated nodemask in
+ * the page allocator means a mempolicy is in effect. Cpuset policy
+ * is enforced in get_page_from_freelist().
*/
- if (nodemask && !nodes_subset(node_states[N_HIGH_MEMORY], *nodemask))
+ if (nodemask && !nodes_subset(node_states[N_HIGH_MEMORY], *nodemask)) {
+ *totalpages = total_swap_pages;
+ for_each_node_mask(nid, *nodemask)
+ *totalpages += node_spanned_pages(nid);
return CONSTRAINT_MEMORY_POLICY;
+ }
/* Check this allocation failure is caused by cpuset's wall function */
for_each_zone_zonelist_nodemask(zone, z, zonelist,
high_zoneidx, nodemask)
if (!cpuset_zone_allowed_softwall(zone, gfp_mask))
- return CONSTRAINT_CPUSET;
+ cpuset_limited = true;
+ if (cpuset_limited) {
+ *totalpages = total_swap_pages;
+ for_each_node_mask(nid, cpuset_current_mems_allowed)
+ *totalpages += node_spanned_pages(nid);
+ return CONSTRAINT_CPUSET;
+ }
return CONSTRAINT_NONE;
}
#else
static enum oom_constraint constrained_alloc(struct zonelist *zonelist,
- gfp_t gfp_mask, nodemask_t *nodemask)
+ gfp_t gfp_mask, nodemask_t *nodemask,
+ unsigned long *totalpages)
{
+ *totalpages = totalram_pages + total_swap_pages;
return CONSTRAINT_NONE;
}
#endif
*
* (not docbooked, we don't want this one cluttering up the manual)
*/
-static struct task_struct *select_bad_process(unsigned long *ppoints,
- struct mem_cgroup *mem, enum oom_constraint constraint,
- const nodemask_t *mask)
+static struct task_struct *select_bad_process(unsigned int *ppoints,
+ unsigned long totalpages, struct mem_cgroup *mem,
+ const nodemask_t *nodemask)
{
struct task_struct *p;
struct task_struct *chosen = NULL;
- struct timespec uptime;
*ppoints = 0;
- do_posix_clock_monotonic_gettime(&uptime);
for_each_process(p) {
- unsigned long points;
+ unsigned int points;
- /* skip the init task and kthreads */
- if (is_global_init(p) || (p->flags & PF_KTHREAD))
- continue;
- if (mem && !task_in_mem_cgroup(p, mem))
- continue;
- if (!has_intersects_mems_allowed(p,
- constraint == CONSTRAINT_MEMORY_POLICY ? mask :
- NULL))
+ if (oom_unkillable_task(p, mem, nodemask))
continue;
/*
* the process of exiting and releasing its resources.
* Otherwise we could get an easy OOM deadlock.
*/
- if ((p->flags & PF_EXITING) && p->mm) {
+ if (thread_group_empty(p) && (p->flags & PF_EXITING) && p->mm) {
if (p != current)
return ERR_PTR(-1UL);
chosen = p;
- *ppoints = ULONG_MAX;
+ *ppoints = 1000;
}
- if (p->signal->oom_adj == OOM_DISABLE)
- continue;
-
- points = badness(p, uptime.tv_sec);
- if (points > *ppoints || !chosen) {
+ points = oom_badness(p, mem, nodemask, totalpages);
+ if (points > *ppoints) {
chosen = p;
*ppoints = points;
}
*
* Dumps the current memory state of all system tasks, excluding kernel threads.
* State information includes task's pid, uid, tgid, vm size, rss, cpu, oom_adj
- * score, and name.
+ * value, oom_score_adj value, and name.
*
* If the actual is non-NULL, only tasks that are a member of the mem_cgroup are
* shown.
struct task_struct *p;
struct task_struct *task;
- printk(KERN_INFO "[ pid ] uid tgid total_vm rss cpu oom_adj "
- "name\n");
+ pr_info("[ pid ] uid tgid total_vm rss cpu oom_adj oom_score_adj name\n");
for_each_process(p) {
if (p->flags & PF_KTHREAD)
continue;
continue;
}
- printk(KERN_INFO "[%5d] %5d %5d %8lu %8lu %3u %3d %s\n",
- task->pid, __task_cred(task)->uid, task->tgid,
- task->mm->total_vm, get_mm_rss(task->mm),
- task_cpu(task), task->signal->oom_adj, task->comm);
+ pr_info("[%5d] %5d %5d %8lu %8lu %3u %3d %5d %s\n",
+ task->pid, __task_cred(task)->uid, task->tgid,
+ task->mm->total_vm, get_mm_rss(task->mm),
+ task_cpu(task), task->signal->oom_adj,
+ task->signal->oom_score_adj, task->comm);
task_unlock(task);
}
}
{
task_lock(current);
pr_warning("%s invoked oom-killer: gfp_mask=0x%x, order=%d, "
- "oom_adj=%d\n",
- current->comm, gfp_mask, order, current->signal->oom_adj);
+ "oom_adj=%d, oom_score_adj=%d\n",
+ current->comm, gfp_mask, order, current->signal->oom_adj,
+ current->signal->oom_score_adj);
cpuset_print_task_mems_allowed(current);
task_unlock(current);
dump_stack();
}
#define K(x) ((x) << (PAGE_SHIFT-10))
-
-/*
- * Send SIGKILL to the selected process irrespective of CAP_SYS_RAW_IO
- * flag though it's unlikely that we select a process with CAP_SYS_RAW_IO
- * set.
- */
-static void __oom_kill_task(struct task_struct *p, int verbose)
+static int oom_kill_task(struct task_struct *p, struct mem_cgroup *mem)
{
- if (is_global_init(p)) {
- WARN_ON(1);
- printk(KERN_WARNING "tried to kill init!\n");
- return;
+ p = find_lock_task_mm(p);
+ if (!p) {
+ task_unlock(p);
+ return 1;
}
+ pr_err("Killed process %d (%s) total-vm:%lukB, anon-rss:%lukB, file-rss:%lukB\n",
+ task_pid_nr(p), p->comm, K(p->mm->total_vm),
+ K(get_mm_counter(p->mm, MM_ANONPAGES)),
+ K(get_mm_counter(p->mm, MM_FILEPAGES)));
+ task_unlock(p);
- p = find_lock_task_mm(p);
- if (!p)
- return;
- if (verbose)
- printk(KERN_ERR "Killed process %d (%s) "
- "vsz:%lukB, anon-rss:%lukB, file-rss:%lukB\n",
- task_pid_nr(p), p->comm,
- K(p->mm->total_vm),
- K(get_mm_counter(p->mm, MM_ANONPAGES)),
- K(get_mm_counter(p->mm, MM_FILEPAGES)));
- task_unlock(p);
+ set_tsk_thread_flag(p, TIF_MEMDIE);
+ force_sig(SIGKILL, p);
/*
* We give our sacrificial lamb high priority and access to
* all the memory it needs. That way it should be able to
* exit() and clear out its resources quickly...
*/
- p->rt.time_slice = HZ;
- set_tsk_thread_flag(p, TIF_MEMDIE);
-
- force_sig(SIGKILL, p);
-}
-
-static int oom_kill_task(struct task_struct *p)
-{
- /* WARNING: mm may not be dereferenced since we did not obtain its
- * value from get_task_mm(p). This is OK since all we need to do is
- * compare mm to q->mm below.
- *
- * Furthermore, even if mm contains a non-NULL value, p->mm may
- * change to NULL at any time since we do not hold task_lock(p).
- * However, this is of no concern to us.
- */
- if (!p->mm || p->signal->oom_adj == OOM_DISABLE)
- return 1;
-
- __oom_kill_task(p, 1);
+ boost_dying_task_prio(p, mem);
return 0;
}
+#undef K
static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
- unsigned long points, struct mem_cgroup *mem,
+ unsigned int points, unsigned long totalpages,
+ struct mem_cgroup *mem, nodemask_t *nodemask,
const char *message)
{
struct task_struct *victim = p;
struct task_struct *child;
struct task_struct *t = p;
- unsigned long victim_points = 0;
- struct timespec uptime;
+ unsigned int victim_points = 0;
if (printk_ratelimit())
dump_header(p, gfp_mask, order, mem);
*/
if (p->flags & PF_EXITING) {
set_tsk_thread_flag(p, TIF_MEMDIE);
+ boost_dying_task_prio(p, mem);
return 0;
}
task_lock(p);
- pr_err("%s: Kill process %d (%s) score %lu or sacrifice child\n",
+ pr_err("%s: Kill process %d (%s) score %d or sacrifice child\n",
message, task_pid_nr(p), p->comm, points);
task_unlock(p);
* parent. This attempts to lose the minimal amount of work done while
* still freeing memory.
*/
- do_posix_clock_monotonic_gettime(&uptime);
do {
list_for_each_entry(child, &t->children, sibling) {
- unsigned long child_points;
+ unsigned int child_points;
- if (child->mm == p->mm)
- continue;
- if (mem && !task_in_mem_cgroup(child, mem))
- continue;
-
- /* badness() returns 0 if the thread is unkillable */
- child_points = badness(child, uptime.tv_sec);
+ /*
+ * oom_badness() returns 0 if the thread is unkillable
+ */
+ child_points = oom_badness(child, mem, nodemask,
+ totalpages);
if (child_points > victim_points) {
victim = child;
victim_points = child_points;
}
} while_each_thread(p, t);
- return oom_kill_task(victim);
+ return oom_kill_task(victim, mem);
+}
+
+/*
+ * Determines whether the kernel must panic because of the panic_on_oom sysctl.
+ */
+static void check_panic_on_oom(enum oom_constraint constraint, gfp_t gfp_mask,
+ int order)
+{
+ if (likely(!sysctl_panic_on_oom))
+ return;
+ if (sysctl_panic_on_oom != 2) {
+ /*
+ * panic_on_oom == 1 only affects CONSTRAINT_NONE, the kernel
+ * does not panic for cpuset, mempolicy, or memcg allocation
+ * failures.
+ */
+ if (constraint != CONSTRAINT_NONE)
+ return;
+ }
+ read_lock(&tasklist_lock);
+ dump_header(NULL, gfp_mask, order, NULL);
+ read_unlock(&tasklist_lock);
+ panic("Out of memory: %s panic_on_oom is enabled\n",
+ sysctl_panic_on_oom == 2 ? "compulsory" : "system-wide");
}
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
void mem_cgroup_out_of_memory(struct mem_cgroup *mem, gfp_t gfp_mask)
{
- unsigned long points = 0;
+ unsigned long limit;
+ unsigned int points = 0;
struct task_struct *p;
- if (sysctl_panic_on_oom == 2)
- panic("out of memory(memcg). panic_on_oom is selected.\n");
+ check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, 0);
+ limit = mem_cgroup_get_limit(mem) >> PAGE_SHIFT;
read_lock(&tasklist_lock);
retry:
- p = select_bad_process(&points, mem, CONSTRAINT_NONE, NULL);
+ p = select_bad_process(&points, limit, mem, NULL);
if (!p || PTR_ERR(p) == -1UL)
goto out;
- if (oom_kill_process(p, gfp_mask, 0, points, mem,
+ if (oom_kill_process(p, gfp_mask, 0, points, limit, mem, NULL,
"Memory cgroup out of memory"))
goto retry;
out:
* if a parallel OOM killing is already taking place that includes a zone in
* the zonelist. Otherwise, locks all zones in the zonelist and returns 1.
*/
-int try_set_zone_oom(struct zonelist *zonelist, gfp_t gfp_mask)
+int try_set_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_mask)
{
struct zoneref *z;
struct zone *zone;
for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) {
/*
* Lock each zone in the zonelist under zone_scan_lock so a
- * parallel invocation of try_set_zone_oom() doesn't succeed
+ * parallel invocation of try_set_zonelist_oom() doesn't succeed
* when it shouldn't.
*/
zone_set_flag(zone, ZONE_OOM_LOCKED);
}
/*
- * Must be called with tasklist_lock held for read.
+ * Try to acquire the oom killer lock for all system zones. Returns zero if a
+ * parallel oom killing is taking place, otherwise locks all zones and returns
+ * non-zero.
*/
-static void __out_of_memory(gfp_t gfp_mask, int order,
- enum oom_constraint constraint, const nodemask_t *mask)
+static int try_set_system_oom(void)
{
- struct task_struct *p;
- unsigned long points;
-
- if (sysctl_oom_kill_allocating_task)
- if (!oom_kill_process(current, gfp_mask, order, 0, NULL,
- "Out of memory (oom_kill_allocating_task)"))
- return;
-retry:
- /*
- * Rambo mode: Shoot down a process and hope it solves whatever
- * issues we may have.
- */
- p = select_bad_process(&points, NULL, constraint, mask);
-
- if (PTR_ERR(p) == -1UL)
- return;
-
- /* Found nothing?!?! Either we hang forever, or we panic. */
- if (!p) {
- read_unlock(&tasklist_lock);
- dump_header(NULL, gfp_mask, order, NULL);
- panic("Out of memory and no killable processes...\n");
- }
+ struct zone *zone;
+ int ret = 1;
- if (oom_kill_process(p, gfp_mask, order, points, NULL,
- "Out of memory"))
- goto retry;
+ spin_lock(&zone_scan_lock);
+ for_each_populated_zone(zone)
+ if (zone_is_oom_locked(zone)) {
+ ret = 0;
+ goto out;
+ }
+ for_each_populated_zone(zone)
+ zone_set_flag(zone, ZONE_OOM_LOCKED);
+out:
+ spin_unlock(&zone_scan_lock);
+ return ret;
}
/*
- * pagefault handler calls into here because it is out of memory but
- * doesn't know exactly how or why.
+ * Clears ZONE_OOM_LOCKED for all system zones so that failed allocation
+ * attempts or page faults may now recall the oom killer, if necessary.
*/
-void pagefault_out_of_memory(void)
+static void clear_system_oom(void)
{
- unsigned long freed = 0;
-
- blocking_notifier_call_chain(&oom_notify_list, 0, &freed);
- if (freed > 0)
- /* Got some memory back in the last second. */
- return;
-
- if (sysctl_panic_on_oom)
- panic("out of memory from page fault. panic_on_oom is selected.\n");
-
- read_lock(&tasklist_lock);
- /* unknown gfp_mask and order */
- __out_of_memory(0, 0, CONSTRAINT_NONE, NULL);
- read_unlock(&tasklist_lock);
+ struct zone *zone;
- /*
- * Give "p" a good chance of killing itself before we
- * retry to allocate memory.
- */
- if (!test_thread_flag(TIF_MEMDIE))
- schedule_timeout_uninterruptible(1);
+ spin_lock(&zone_scan_lock);
+ for_each_populated_zone(zone)
+ zone_clear_flag(zone, ZONE_OOM_LOCKED);
+ spin_unlock(&zone_scan_lock);
}
/**
void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask,
int order, nodemask_t *nodemask)
{
+ struct task_struct *p;
+ unsigned long totalpages;
unsigned long freed = 0;
- enum oom_constraint constraint;
+ unsigned int points;
+ enum oom_constraint constraint = CONSTRAINT_NONE;
blocking_notifier_call_chain(&oom_notify_list, 0, &freed);
if (freed > 0)
*/
if (fatal_signal_pending(current)) {
set_thread_flag(TIF_MEMDIE);
+ boost_dying_task_prio(current, NULL);
return;
}
- if (sysctl_panic_on_oom == 2) {
- dump_header(NULL, gfp_mask, order, NULL);
- panic("out of memory. Compulsory panic_on_oom is selected.\n");
- }
-
/*
* Check if there were limitations on the allocation (only relevant for
* NUMA) that may require different handling.
*/
- constraint = constrained_alloc(zonelist, gfp_mask, nodemask);
+ constraint = constrained_alloc(zonelist, gfp_mask, nodemask,
+ &totalpages);
+ check_panic_on_oom(constraint, gfp_mask, order);
+
read_lock(&tasklist_lock);
- if (unlikely(sysctl_panic_on_oom)) {
+ if (sysctl_oom_kill_allocating_task &&
+ !oom_unkillable_task(current, NULL, nodemask) &&
+ (current->signal->oom_adj != OOM_DISABLE)) {
/*
- * panic_on_oom only affects CONSTRAINT_NONE, the kernel
- * should not panic for cpuset or mempolicy induced memory
- * failures.
+ * oom_kill_process() needs tasklist_lock held. If it returns
+ * non-zero, current could not be killed so we must fallback to
+ * the tasklist scan.
*/
- if (constraint == CONSTRAINT_NONE) {
- dump_header(NULL, gfp_mask, order, NULL);
- read_unlock(&tasklist_lock);
- panic("Out of memory: panic_on_oom is enabled\n");
- }
+ if (!oom_kill_process(current, gfp_mask, order, 0, totalpages,
+ NULL, nodemask,
+ "Out of memory (oom_kill_allocating_task)"))
+ return;
+ }
+
+retry:
+ p = select_bad_process(&points, totalpages, NULL,
+ constraint == CONSTRAINT_MEMORY_POLICY ? nodemask :
+ NULL);
+ if (PTR_ERR(p) == -1UL)
+ return;
+
+ /* Found nothing?!?! Either we hang forever, or we panic. */
+ if (!p) {
+ dump_header(NULL, gfp_mask, order, NULL);
+ read_unlock(&tasklist_lock);
+ panic("Out of memory and no killable processes...\n");
}
- __out_of_memory(gfp_mask, order, constraint, nodemask);
+
+ if (oom_kill_process(p, gfp_mask, order, points, totalpages, NULL,
+ nodemask, "Out of memory"))
+ goto retry;
read_unlock(&tasklist_lock);
/*
if (!test_thread_flag(TIF_MEMDIE))
schedule_timeout_uninterruptible(1);
}
+
+/*
+ * The pagefault handler calls here because it is out of memory, so kill a
+ * memory-hogging task. If a populated zone has ZONE_OOM_LOCKED set, a parallel
+ * oom killing is already in progress so do nothing. If a task is found with
+ * TIF_MEMDIE set, it has been killed so do nothing and allow it to exit.
+ */
+void pagefault_out_of_memory(void)
+{
+ if (try_set_system_oom()) {
+ out_of_memory(NULL, 0, 0, NULL);
+ clear_system_oom();
+ }
+ if (!test_thread_flag(TIF_MEMDIE))
+ schedule_timeout_uninterruptible(1);
+}
git://bbs.cooldavid.org / net-next-2.6.git / blobdiff