aboutsummaryrefslogtreecommitdiff
path: root/mm/oom_kill.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/oom_kill.c')
-rw-r--r--mm/oom_kill.c90
1 files changed, 53 insertions, 37 deletions
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 0399f146ae4..3291e82d435 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -47,19 +47,21 @@ static DEFINE_SPINLOCK(zone_scan_lock);
#ifdef CONFIG_NUMA
/**
* has_intersects_mems_allowed() - check task eligiblity for kill
- * @tsk: task struct of which task to consider
+ * @start: task struct of which task to consider
* @mask: nodemask passed to page allocator for mempolicy ooms
*
* Task eligibility is determined by whether or not a candidate task, @tsk,
* shares the same mempolicy nodes as current if it is bound by such a policy
* and whether or not it has the same set of allowed cpuset nodes.
*/
-static bool has_intersects_mems_allowed(struct task_struct *tsk,
+static bool has_intersects_mems_allowed(struct task_struct *start,
const nodemask_t *mask)
{
- struct task_struct *start = tsk;
+ struct task_struct *tsk;
+ bool ret = false;
- do {
+ rcu_read_lock();
+ for_each_thread(start, tsk) {
if (mask) {
/*
* If this is a mempolicy constrained oom, tsk's
@@ -67,19 +69,20 @@ static bool has_intersects_mems_allowed(struct task_struct *tsk,
* mempolicy intersects current, otherwise it may be
* needlessly killed.
*/
- if (mempolicy_nodemask_intersects(tsk, mask))
- return true;
+ ret = mempolicy_nodemask_intersects(tsk, mask);
} else {
/*
* This is not a mempolicy constrained oom, so only
* check the mems of tsk's cpuset.
*/
- if (cpuset_mems_allowed_intersects(current, tsk))
- return true;
+ ret = cpuset_mems_allowed_intersects(current, tsk);
}
- } while_each_thread(start, tsk);
+ if (ret)
+ break;
+ }
+ rcu_read_unlock();
- return false;
+ return ret;
}
#else
static bool has_intersects_mems_allowed(struct task_struct *tsk,
@@ -97,16 +100,21 @@ static bool has_intersects_mems_allowed(struct task_struct *tsk,
*/
struct task_struct *find_lock_task_mm(struct task_struct *p)
{
- struct task_struct *t = p;
+ struct task_struct *t;
+
+ rcu_read_lock();
- do {
+ for_each_thread(p, t) {
task_lock(t);
if (likely(t->mm))
- return t;
+ goto found;
task_unlock(t);
- } while_each_thread(p, t);
+ }
+ t = NULL;
+found:
+ rcu_read_unlock();
- return NULL;
+ return t;
}
/* return true if the task is not adequate as candidate victim task. */
@@ -161,7 +169,7 @@ unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg,
* The baseline for the badness score is the proportion of RAM that each
* task's rss, pagetable and swap space use.
*/
- points = get_mm_rss(p->mm) + p->mm->nr_ptes +
+ points = get_mm_rss(p->mm) + atomic_long_read(&p->mm->nr_ptes) +
get_mm_counter(p->mm, MM_SWAPENTS);
task_unlock(p);
@@ -170,7 +178,7 @@ unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg,
* implementation used by LSMs.
*/
if (has_capability_noaudit(p, CAP_SYS_ADMIN))
- adj -= 30;
+ points -= (points * 3) / 100;
/* Normalize to oom_score_adj units */
adj *= totalpages / 1000;
@@ -288,7 +296,7 @@ enum oom_scan_t oom_scan_process_thread(struct task_struct *task,
/*
* Simple selection loop. We chose the process with the highest
- * number of 'points'.
+ * number of 'points'. Returns -1 on scan abort.
*
* (not docbooked, we don't want this one cluttering up the manual)
*/
@@ -301,7 +309,7 @@ static struct task_struct *select_bad_process(unsigned int *ppoints,
unsigned long chosen_points = 0;
rcu_read_lock();
- do_each_thread(g, p) {
+ for_each_process_thread(g, p) {
unsigned int points;
switch (oom_scan_process_thread(p, totalpages, nodemask,
@@ -314,16 +322,20 @@ static struct task_struct *select_bad_process(unsigned int *ppoints,
continue;
case OOM_SCAN_ABORT:
rcu_read_unlock();
- return ERR_PTR(-1UL);
+ return (struct task_struct *)(-1UL);
case OOM_SCAN_OK:
break;
};
points = oom_badness(p, NULL, nodemask, totalpages);
- if (points > chosen_points) {
- chosen = p;
- chosen_points = points;
- }
- } while_each_thread(g, p);
+ if (!points || points < chosen_points)
+ continue;
+ /* Prefer thread group leaders for display purposes */
+ if (points == chosen_points && thread_group_leader(chosen))
+ continue;
+
+ chosen = p;
+ chosen_points = points;
+ }
if (chosen)
get_task_struct(chosen);
rcu_read_unlock();
@@ -364,10 +376,10 @@ static void dump_tasks(const struct mem_cgroup *memcg, const nodemask_t *nodemas
continue;
}
- pr_info("[%5d] %5d %5d %8lu %8lu %7lu %8lu %5hd %s\n",
+ pr_info("[%5d] %5d %5d %8lu %8lu %7ld %8lu %5hd %s\n",
task->pid, from_kuid(&init_user_ns, task_uid(task)),
task->tgid, task->mm->total_vm, get_mm_rss(task->mm),
- task->mm->nr_ptes,
+ atomic_long_read(&task->mm->nr_ptes),
get_mm_counter(task->mm, MM_SWAPENTS),
task->signal->oom_score_adj, task->comm);
task_unlock(task);
@@ -386,8 +398,10 @@ static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order,
cpuset_print_task_mems_allowed(current);
task_unlock(current);
dump_stack();
- mem_cgroup_print_oom_info(memcg, p);
- show_mem(SHOW_MEM_FILTER_NODES);
+ if (memcg)
+ mem_cgroup_print_oom_info(memcg, p);
+ else
+ show_mem(SHOW_MEM_FILTER_NODES);
if (sysctl_oom_dump_tasks)
dump_tasks(memcg, nodemask);
}
@@ -404,7 +418,7 @@ void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
{
struct task_struct *victim = p;
struct task_struct *child;
- struct task_struct *t = p;
+ struct task_struct *t;
struct mm_struct *mm;
unsigned int victim_points = 0;
static DEFINE_RATELIMIT_STATE(oom_rs, DEFAULT_RATELIMIT_INTERVAL,
@@ -435,7 +449,7 @@ void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
* still freeing memory.
*/
read_lock(&tasklist_lock);
- do {
+ for_each_thread(p, t) {
list_for_each_entry(child, &t->children, sibling) {
unsigned int child_points;
@@ -453,13 +467,11 @@ void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
get_task_struct(victim);
}
}
- } while_each_thread(p, t);
+ }
read_unlock(&tasklist_lock);
- rcu_read_lock();
p = find_lock_task_mm(victim);
if (!p) {
- rcu_read_unlock();
put_task_struct(victim);
return;
} else if (victim != p) {
@@ -485,6 +497,7 @@ void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
* That thread will now get access to memory reserves since it has a
* pending fatal signal.
*/
+ rcu_read_lock();
for_each_process(p)
if (p->mm == mm && !same_thread_group(p, victim) &&
!(p->flags & PF_KTHREAD)) {
@@ -655,7 +668,7 @@ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask,
dump_header(NULL, gfp_mask, order, NULL, mpol_mask);
panic("Out of memory and no killable processes...\n");
}
- if (PTR_ERR(p) != -1UL) {
+ if (p != (void *)-1UL) {
oom_kill_process(p, gfp_mask, order, points, totalpages, NULL,
nodemask, "Out of memory");
killed = 1;
@@ -676,9 +689,12 @@ out:
*/
void pagefault_out_of_memory(void)
{
- struct zonelist *zonelist = node_zonelist(first_online_node,
- GFP_KERNEL);
+ struct zonelist *zonelist;
+
+ if (mem_cgroup_oom_synchronize(true))
+ return;
+ zonelist = node_zonelist(first_online_node, GFP_KERNEL);
if (try_set_zonelist_oom(zonelist, GFP_KERNEL)) {
out_of_memory(NULL, 0, 0, NULL, false);
clear_zonelist_oom(zonelist, GFP_KERNEL);