* @pi_tree_entry: pi node to enqueue into the mutex owner waiters tree
* @task: task reference to the blocked task
* @lock: Pointer to the rt_mutex on which the waiter blocks
+ * @wake_state: Wakeup state to use (TASK_NORMAL or TASK_RTLOCK_WAIT)
* @prio: Priority of the waiter
* @deadline: Deadline of the waiter if applicable
+ * @ww_ctx: WW context pointer
*/
struct rt_mutex_waiter {
struct rb_node tree_entry;
struct rb_node pi_tree_entry;
struct task_struct *task;
- struct rt_mutex *lock;
+ struct rt_mutex_base *lock;
+ unsigned int wake_state;
int prio;
u64 deadline;
+ struct ww_acquire_ctx *ww_ctx;
};
+/**
+ * rt_wake_q_head - Wrapper around regular wake_q_head to support
+ * "sleeping" spinlocks on RT
+ * @head: The regular wake_q_head for sleeping lock variants
+ * @rtlock_task: Task pointer for RT lock (spin/rwlock) wakeups
+ */
+struct rt_wake_q_head {
+ struct wake_q_head head;
+ struct task_struct *rtlock_task;
+};
+
+#define DEFINE_RT_WAKE_Q(name) \
+ struct rt_wake_q_head name = { \
+ .head = WAKE_Q_HEAD_INITIALIZER(name.head), \
+ .rtlock_task = NULL, \
+ }
+
+/*
+ * PI-futex support (proxy locking functions, etc.):
+ */
+extern void rt_mutex_init_proxy_locked(struct rt_mutex_base *lock,
+ struct task_struct *proxy_owner);
+extern void rt_mutex_proxy_unlock(struct rt_mutex_base *lock);
+extern int __rt_mutex_start_proxy_lock(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter,
+ struct task_struct *task);
+extern int rt_mutex_start_proxy_lock(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter,
+ struct task_struct *task);
+extern int rt_mutex_wait_proxy_lock(struct rt_mutex_base *lock,
+ struct hrtimer_sleeper *to,
+ struct rt_mutex_waiter *waiter);
+extern bool rt_mutex_cleanup_proxy_lock(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter);
+
+extern int rt_mutex_futex_trylock(struct rt_mutex_base *l);
+extern int __rt_mutex_futex_trylock(struct rt_mutex_base *l);
+
+extern void rt_mutex_futex_unlock(struct rt_mutex_base *lock);
+extern bool __rt_mutex_futex_unlock(struct rt_mutex_base *lock,
+ struct rt_wake_q_head *wqh);
+
+extern void rt_mutex_postunlock(struct rt_wake_q_head *wqh);
+
/*
* Must be guarded because this header is included from rcu/tree_plugin.h
* unconditionally.
*/
#ifdef CONFIG_RT_MUTEXES
-static inline int rt_mutex_has_waiters(struct rt_mutex *lock)
+static inline int rt_mutex_has_waiters(struct rt_mutex_base *lock)
{
return !RB_EMPTY_ROOT(&lock->waiters.rb_root);
}
-static inline struct rt_mutex_waiter *rt_mutex_top_waiter(struct rt_mutex *lock)
+/*
+ * Lockless speculative check whether @waiter is still the top waiter on
+ * @lock. This is solely comparing pointers and not derefencing the
+ * leftmost entry which might be about to vanish.
+ */
+static inline bool rt_mutex_waiter_is_top_waiter(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter)
+{
+ struct rb_node *leftmost = rb_first_cached(&lock->waiters);
+
+ return rb_entry(leftmost, struct rt_mutex_waiter, tree_entry) == waiter;
+}
+
+static inline struct rt_mutex_waiter *rt_mutex_top_waiter(struct rt_mutex_base *lock)
{
struct rb_node *leftmost = rb_first_cached(&lock->waiters);
struct rt_mutex_waiter *w = NULL;
#define RT_MUTEX_HAS_WAITERS 1UL
-static inline struct task_struct *rt_mutex_owner(struct rt_mutex *lock)
+static inline struct task_struct *rt_mutex_owner(struct rt_mutex_base *lock)
{
unsigned long owner = (unsigned long) READ_ONCE(lock->owner);
return (struct task_struct *) (owner & ~RT_MUTEX_HAS_WAITERS);
}
-#else /* CONFIG_RT_MUTEXES */
-/* Used in rcu/tree_plugin.h */
-static inline struct task_struct *rt_mutex_owner(struct rt_mutex *lock)
-{
- return NULL;
-}
-#endif /* !CONFIG_RT_MUTEXES */
/*
* Constants for rt mutex functions which have a selectable deadlock
RT_MUTEX_FULL_CHAINWALK,
};
-static inline void __rt_mutex_basic_init(struct rt_mutex *lock)
+static inline void __rt_mutex_base_init(struct rt_mutex_base *lock)
{
- lock->owner = NULL;
raw_spin_lock_init(&lock->wait_lock);
lock->waiters = RB_ROOT_CACHED;
+ lock->owner = NULL;
}
-/*
- * PI-futex support (proxy locking functions, etc.):
- */
-extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
- struct task_struct *proxy_owner);
-extern void rt_mutex_proxy_unlock(struct rt_mutex *lock);
-extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
-extern int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter,
- struct task_struct *task);
-extern int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter,
- struct task_struct *task);
-extern int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
- struct hrtimer_sleeper *to,
- struct rt_mutex_waiter *waiter);
-extern bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter);
-
-extern int rt_mutex_futex_trylock(struct rt_mutex *l);
-extern int __rt_mutex_futex_trylock(struct rt_mutex *l);
-
-extern void rt_mutex_futex_unlock(struct rt_mutex *lock);
-extern bool __rt_mutex_futex_unlock(struct rt_mutex *lock,
- struct wake_q_head *wqh);
-
-extern void rt_mutex_postunlock(struct wake_q_head *wake_q);
-
/* Debug functions */
-static inline void debug_rt_mutex_unlock(struct rt_mutex *lock)
+static inline void debug_rt_mutex_unlock(struct rt_mutex_base *lock)
{
if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES))
DEBUG_LOCKS_WARN_ON(rt_mutex_owner(lock) != current);
}
-static inline void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock)
+static inline void debug_rt_mutex_proxy_unlock(struct rt_mutex_base *lock)
{
if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES))
DEBUG_LOCKS_WARN_ON(!rt_mutex_owner(lock));
memset(waiter, 0x22, sizeof(*waiter));
}
+static inline void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
+{
+ debug_rt_mutex_init_waiter(waiter);
+ RB_CLEAR_NODE(&waiter->pi_tree_entry);
+ RB_CLEAR_NODE(&waiter->tree_entry);
+ waiter->wake_state = TASK_NORMAL;
+ waiter->task = NULL;
+}
+
+static inline void rt_mutex_init_rtlock_waiter(struct rt_mutex_waiter *waiter)
+{
+ rt_mutex_init_waiter(waiter);
+ waiter->wake_state = TASK_RTLOCK_WAIT;
+}
+
+#else /* CONFIG_RT_MUTEXES */
+/* Used in rcu/tree_plugin.h */
+static inline struct task_struct *rt_mutex_owner(struct rt_mutex_base *lock)
+{
+ return NULL;
+}
+#endif /* !CONFIG_RT_MUTEXES */
+
#endif
projects / linux-2.6-microblaze.git / blobdiff