diff --git a/fs/exec.c b/fs/exec.c
index 25dcbe5fc35664d6f389ce48f051d6528d607014..36254645b7cc4d81f7c73b2940767fe06de1642c 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -841,10 +841,6 @@ static int exec_mmap(struct mm_struct *mm)
tsk->mm = mm;
tsk->active_mm = mm;
activate_mm(active_mm, mm);
- if (old_mm && tsk->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) {
- atomic_dec(&old_mm->oom_disable_count);
- atomic_inc(&tsk->mm->oom_disable_count);
- }
task_unlock(tsk);
arch_pick_mmap_layout(mm);
if (old_mm) {
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 5eb02069e1b817730050b7b46304a9244c064bde..8f0087e20e168ee04e6b14e7ef05a68f13e4b58e 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1107,13 +1107,6 @@ static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
goto err_sighand;
}
- if (oom_adjust != task->signal->oom_adj) {
- if (oom_adjust == OOM_DISABLE)
- atomic_inc(&task->mm->oom_disable_count);
- if (task->signal->oom_adj == OOM_DISABLE)
- atomic_dec(&task->mm->oom_disable_count);
- }
-
/*
* Warn that /proc/pid/oom_adj is deprecated, see
* Documentation/feature-removal-schedule.txt.
@@ -1215,12 +1208,6 @@ static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
goto err_sighand;
}
- if (oom_score_adj != task->signal->oom_score_adj) {
- if (oom_score_adj == OOM_SCORE_ADJ_MIN)
- atomic_inc(&task->mm->oom_disable_count);
- if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
- atomic_dec(&task->mm->oom_disable_count);
- }
task->signal->oom_score_adj = oom_score_adj;
if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
task->signal->oom_score_adj_min = oom_score_adj;
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index c93d00a6e95d19ca347ab52761de58bf91141c74..6456624aa9644573ea5298e114a2230564f5b54e 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -336,9 +336,6 @@ struct mm_struct {
unsigned int token_priority;
unsigned int last_interval;
- /* How many tasks sharing this mm are OOM_DISABLE */
- atomic_t oom_disable_count;
-
unsigned long flags; /* Must use atomic bitops to access the bits */
struct core_state *core_state; /* coredumping support */
diff --git a/kernel/exit.c b/kernel/exit.c
index 2913b3509d4288026990cc087894e69eace6c564..d0b7d988f8735beb6e1e7b5f7b42ecbd04b91bf5 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -681,8 +681,6 @@ static void exit_mm(struct task_struct * tsk)
enter_lazy_tlb(mm, current);
/* We don't want this task to be frozen prematurely */
clear_freeze_flag(tsk);
- if (tsk->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
- atomic_dec(&mm->oom_disable_count);
task_unlock(tsk);
mm_update_next_owner(mm);
mmput(mm);
diff --git a/kernel/fork.c b/kernel/fork.c
index 8e6b6f4fb272ba498a4acdbcb6a29c8f7e6c87dd..70d76191afb9449033f09ef2c3532d450defdd49 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -501,7 +501,6 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p)
mm->cached_hole_size = ~0UL;
mm_init_aio(mm);
mm_init_owner(mm, p);
- atomic_set(&mm->oom_disable_count, 0);
if (likely(!mm_alloc_pgd(mm))) {
mm->def_flags = 0;
@@ -816,8 +815,6 @@ static int copy_mm(unsigned long clone_flags, struct task_struct *tsk)
/* Initializing for Swap token stuff */
mm->token_priority = 0;
mm->last_interval = 0;
- if (tsk->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
- atomic_inc(&mm->oom_disable_count);
tsk->mm = mm;
tsk->active_mm = mm;
@@ -1391,13 +1388,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
bad_fork_cleanup_namespaces:
exit_task_namespaces(p);
bad_fork_cleanup_mm:
- if (p->mm) {
- task_lock(p);
- if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
- atomic_dec(&p->mm->oom_disable_count);
- task_unlock(p);
+ if (p->mm)
mmput(p->mm);
- }
bad_fork_cleanup_signal:
if (!(clone_flags & CLONE_THREAD))
free_signal_struct(p->signal);
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index b0d8943bc9fd798530e8c5b5899da026ecc74f56..2b97e8f04607b2ccb0011a3af5996aa41efe069b 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -54,13 +54,7 @@ int test_set_oom_score_adj(int new_val)
spin_lock_irq(&sighand->siglock);
old_val = current->signal->oom_score_adj;
- if (new_val != old_val) {
- if (new_val == OOM_SCORE_ADJ_MIN)
- atomic_inc(¤t->mm->oom_disable_count);
- else if (old_val == OOM_SCORE_ADJ_MIN)
- atomic_dec(¤t->mm->oom_disable_count);
- current->signal->oom_score_adj = new_val;
- }
+ current->signal->oom_score_adj = new_val;
spin_unlock_irq(&sighand->siglock);
return old_val;
@@ -172,16 +166,6 @@ unsigned int oom_badness(struct task_struct *p, struct mem_cgroup *mem,
if (!p)
return 0;
- /*
- * Shortcut check for a thread sharing p->mm that is OOM_SCORE_ADJ_MIN
- * so the entire heuristic doesn't need to be executed for something
- * that cannot be killed.
- */
- if (atomic_read(&p->mm->oom_disable_count)) {
- task_unlock(p);
- return 0;
- }
-
/*
* The memory controller may have a limit of 0 bytes, so avoid a divide
* by zero, if necessary.
@@ -451,6 +435,9 @@ static int oom_kill_task(struct task_struct *p, struct mem_cgroup *mem)
for_each_process(q)
if (q->mm == mm && !same_thread_group(q, p) &&
!(q->flags & PF_KTHREAD)) {
+ if (q->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
+ continue;
+
task_lock(q); /* Protect ->comm from prctl() */
pr_err("Kill process %d (%s) sharing same memory\n",
task_pid_nr(q), q->comm);
@@ -727,7 +714,7 @@ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask,
read_lock(&tasklist_lock);
if (sysctl_oom_kill_allocating_task &&
!oom_unkillable_task(current, NULL, nodemask) &&
- current->mm && !atomic_read(¤t->mm->oom_disable_count)) {
+ current->mm) {
/*
* oom_kill_process() needs tasklist_lock held. If it returns
* non-zero, current could not be killed so we must fallback to