diff options
Diffstat (limited to 'kernel/locking/mutex.c')
| -rw-r--r-- | kernel/locking/mutex.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index c0731685603f..9b349619f431 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -364,7 +364,11 @@ bool mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner) */ barrier(); - if (!owner->on_cpu || need_resched()) { + /* + * Use vcpu_is_preempted to detect lock holder preemption issue. + */ + if (!owner->on_cpu || need_resched() || + vcpu_is_preempted(task_cpu(owner))) { ret = false; break; } @@ -389,8 +393,13 @@ static inline int mutex_can_spin_on_owner(struct mutex *lock) rcu_read_lock(); owner = __mutex_owner(lock); + + /* + * As lock holder preemption issue, we both skip spinning if task is not + * on cpu or its cpu is preempted + */ if (owner) - retval = owner->on_cpu; + retval = owner->on_cpu && !vcpu_is_preempted(task_cpu(owner)); rcu_read_unlock(); /* |