Event mutex implementation. More...

Functions
void	event_mutex_init (struct event_mutex em, struct waitset waitset)
	Initialise a new event mutex.

bool	event_mutex_enqueue_lock (struct event_mutex em, struct event_queue_node qn, struct event_closure lockcont)
	Enqueue a lock acquisition request for the mutex. More...

void	event_mutex_threaded_lock (struct event_mutex *em)
	Acquire the mutex, blocking the calling thread until done. More...

void	event_mutex_unlock (struct event_mutex *em)
	Unlock the mutex, which must be held by the caller. More...

Detailed Description

Event mutex implementation.

This code implements an event-driven mutex which supports lock acquisition events.

Function Documentation

bool event_mutex_enqueue_lock	(	struct event_mutex *	em,
		struct event_queue_node *	qn,
		struct event_closure	lockcont
	)

Enqueue a lock acquisition request for the mutex.

Parameters

em	Event mutex
qn	Storage for queue node. allocated by caller, live until continuation runs
lockcont	Continuation for lock acquisition

Returns: true iff the lock was acquired and the continuation run, false if enqueued

void event_mutex_threaded_lock ( struct event_mutex * em )

Acquire the mutex, blocking the calling thread until done.

Parameters

em	Event mutex

void event_mutex_unlock ( struct event_mutex * em )

Unlock the mutex, which must be held by the caller.

Note: This always prefers releasing a thread rather than triggering the next event, so threaded code can starve event-driven code in a program that mixes the two models.