1 files changed, 5 insertions, 10 deletions

diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h
index 4ab704339656..c6d1c7da3ea5 100644
--- a/kernel/sched/stats.h
+++ b/kernel/sched/stats.h
@@ -174,7 +174,8 @@ static inline bool cputimer_running(struct task_struct *tsk)
 {
         struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
 
-        if (!cputimer->running)
+        /* Check if cputimer isn't running. This is accessed without locking. */
+        if (!READ_ONCE(cputimer->running))
                 return false;
 
         /*
@@ -215,9 +216,7 @@ static inline void account_group_user_time(struct task_struct *tsk,
         if (!cputimer_running(tsk))
                 return;
 
-        raw_spin_lock(&cputimer->lock);
-        cputimer->cputime.utime += cputime;
-        raw_spin_unlock(&cputimer->lock);
+        atomic64_add(cputime, &cputimer->utime);
 }
 
 /**
@@ -238,9 +237,7 @@ static inline void account_group_system_time(struct task_struct *tsk,
         if (!cputimer_running(tsk))
                 return;
 
-        raw_spin_lock(&cputimer->lock);
-        cputimer->cputime.stime += cputime;
-        raw_spin_unlock(&cputimer->lock);
+        atomic64_add(cputime, &cputimer->stime);
 }
 
 /**
@@ -261,7 +258,5 @@ static inline void account_group_exec_runtime(struct task_struct *tsk,
         if (!cputimer_running(tsk))
                 return;
 
-        raw_spin_lock(&cputimer->lock);
-        cputimer->cputime.sum_exec_runtime += ns;
-        raw_spin_unlock(&cputimer->lock);
+        atomic64_add(ns, &cputimer->sum_exec_runtime);
 }