diff options
| -rw-r--r-- | kernel/locking/rtmutex.c | 29 | ||||
| -rw-r--r-- | kernel/locking/rtmutex_common.h | 1 |
2 files changed, 28 insertions, 2 deletions
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 2c49d76f96c3..196cc460e38d 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -236,8 +236,7 @@ rt_mutex_waiter_less(struct rt_mutex_waiter *left, * then right waiter has a dl_prio() too. */ if (dl_prio(left->prio)) - return dl_time_before(left->task->dl.deadline, - right->task->dl.deadline); + return dl_time_before(left->deadline, right->deadline); return 0; } @@ -704,7 +703,26 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, /* [7] Requeue the waiter in the lock waiter tree. */ rt_mutex_dequeue(lock, waiter); + + /* + * Update the waiter prio fields now that we're dequeued. + * + * These values can have changed through either: + * + * sys_sched_set_scheduler() / sys_sched_setattr() + * + * or + * + * DL CBS enforcement advancing the effective deadline. + * + * Even though pi_waiters also uses these fields, and that tree is only + * updated in [11], we can do this here, since we hold [L], which + * serializes all pi_waiters access and rb_erase() does not care about + * the values of the node being removed. + */ waiter->prio = task->prio; + waiter->deadline = task->dl.deadline; + rt_mutex_enqueue(lock, waiter); /* [8] Release the task */ @@ -831,6 +849,8 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task, struct rt_mutex_waiter *waiter) { + lockdep_assert_held(&lock->wait_lock); + /* * Before testing whether we can acquire @lock, we set the * RT_MUTEX_HAS_WAITERS bit in @lock->owner. This forces all @@ -958,6 +978,8 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, struct rt_mutex *next_lock; int chain_walk = 0, res; + lockdep_assert_held(&lock->wait_lock); + /* * Early deadlock detection. We really don't want the task to * enqueue on itself just to untangle the mess later. It's not @@ -975,6 +997,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, waiter->task = task; waiter->lock = lock; waiter->prio = task->prio; + waiter->deadline = task->dl.deadline; /* Get the top priority waiter on the lock */ if (rt_mutex_has_waiters(lock)) @@ -1080,6 +1103,8 @@ static void remove_waiter(struct rt_mutex *lock, struct task_struct *owner = rt_mutex_owner(lock); struct rt_mutex *next_lock; + lockdep_assert_held(&lock->wait_lock); + raw_spin_lock(¤t->pi_lock); rt_mutex_dequeue(lock, waiter); current->pi_blocked_on = NULL; diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h index e317e1cbb3eb..50848b460851 100644 --- a/kernel/locking/rtmutex_common.h +++ b/kernel/locking/rtmutex_common.h @@ -33,6 +33,7 @@ struct rt_mutex_waiter { struct rt_mutex *deadlock_lock; #endif int prio; + u64 deadline; }; /* |