diff options
Diffstat (limited to 'kernel/locking/mutex.c')
| -rw-r--r-- | kernel/locking/mutex.c | 40 |
1 files changed, 26 insertions, 14 deletions
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 427187ff02db..186b463fe326 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -674,6 +674,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas goto err_early_kill; } + raw_spin_lock(¤t->blocked_lock); __set_task_blocked_on(current, lock); set_current_state(state); trace_contention_begin(lock, LCB_F_MUTEX); @@ -687,8 +688,9 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas * the handoff. */ if (__mutex_trylock(lock)) - goto acquired; + break; + raw_spin_unlock(¤t->blocked_lock); /* * Check for signals and kill conditions while holding * wait_lock. This ensures the lock cancellation is ordered @@ -711,12 +713,14 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas first = lock->first_waiter == &waiter; + raw_spin_lock_irqsave(&lock->wait_lock, flags); + raw_spin_lock(¤t->blocked_lock); /* * As we likely have been woken up by task * that has cleared our blocked_on state, re-set * it to the lock we are trying to acquire. */ - set_task_blocked_on(current, lock); + __set_task_blocked_on(current, lock); set_current_state(state); /* * Here we order against unlock; we must either see it change @@ -727,25 +731,33 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas break; if (first) { - trace_contention_begin(lock, LCB_F_MUTEX | LCB_F_SPIN); + bool opt_acquired; + /* * mutex_optimistic_spin() can call schedule(), so - * clear blocked on so we don't become unselectable + * we need to release these locks before calling it, + * and clear blocked on so we don't become unselectable * to run. */ - clear_task_blocked_on(current, lock); - if (mutex_optimistic_spin(lock, ww_ctx, &waiter)) + __clear_task_blocked_on(current, lock); + raw_spin_unlock(¤t->blocked_lock); + raw_spin_unlock_irqrestore(&lock->wait_lock, flags); + + trace_contention_begin(lock, LCB_F_MUTEX | LCB_F_SPIN); + opt_acquired = mutex_optimistic_spin(lock, ww_ctx, &waiter); + + raw_spin_lock_irqsave(&lock->wait_lock, flags); + raw_spin_lock(¤t->blocked_lock); + __set_task_blocked_on(current, lock); + + if (opt_acquired) break; - set_task_blocked_on(current, lock); trace_contention_begin(lock, LCB_F_MUTEX); } - - raw_spin_lock_irqsave(&lock->wait_lock, flags); } - raw_spin_lock_irqsave(&lock->wait_lock, flags); -acquired: __clear_task_blocked_on(current, lock); __set_current_state(TASK_RUNNING); + raw_spin_unlock(¤t->blocked_lock); if (ww_ctx) { /* @@ -773,11 +785,11 @@ skip_wait: return 0; err: - __clear_task_blocked_on(current, lock); + clear_task_blocked_on(current, lock); __set_current_state(TASK_RUNNING); __mutex_remove_waiter(lock, &waiter); err_early_kill: - WARN_ON(__get_task_blocked_on(current)); + WARN_ON(get_task_blocked_on(current)); trace_contention_end(lock, ret); raw_spin_unlock_irqrestore_wake(&lock->wait_lock, flags, &wake_q); debug_mutex_free_waiter(&waiter); @@ -993,7 +1005,7 @@ static noinline void __sched __mutex_unlock_slowpath(struct mutex *lock, unsigne next = waiter->task; debug_mutex_wake_waiter(lock, waiter); - __clear_task_blocked_on(next, lock); + set_task_blocked_on_waking(next, lock); wake_q_add(&wake_q, next); } |
