w_pthread_lock_t Struct Reference

Inherited by mcs_rwlock [protected].

Inheritance diagram for w_pthread_lock_t:

[legend]Collaboration diagram for w_pthread_lock_t:

[legend]List of all members.

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Detailed Description

Wrapper for pthread mutexes, with a queue-based lock API.

This lock uses a Pthreads mutex for the lock.

This is not a true queue-based lock, since release doesn't inform the next node in the queue, and in fact the nodes aren't kept in a queue. It just gives pthread mutexes the same API as the other queue-based locks so that we use the same idioms for critical sections based on different kinds of locks.

The idiom for using these locks is that the qnode is on a threads's stack, so the qnode implicitly identifies the owning thread.

This allows us to add an is_mine() capability that otherwise the pthread mutexen don't have.

Finally, using this class ensures that the pthread_mutex_init/destroy is done.

See also: Synchronization Primitives

Definition at line 400 of file sthread.h.

Public Member Functions
	w_pthread_lock_t ()
	~w_pthread_lock_t ()
bool	attempt (ext_qnode *me)
	Returns true if success.
void *	acquire (ext_qnode *me)
	Acquire the lock and set the qnode to refer to this lock.
void	release (ext_qnode &me)
	Release the lock and clear the qnode.
void	release (ext_qnode_ptr me)
	Release the lock and clear the qnode.
bool	is_mine (ext_qnode *me) const
	Return true if this thread holds the lock.

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Member Function Documentation

bool w_pthread_lock_t::is_mine

(

ext_qnode *

me

)

const [inline]

Return true if this thread holds the lock.

This method doesn't actually check for this pthread holding the lock, but it checks that the qnode reference is to this lock. The idiom for using these locks is that the qnode is on a threads's stack, so the qnode implicitly identifies the owning thread.

Definition at line 491 of file sthread.h.

References w_assert1.

Referenced by acquire().

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The documentation for this struct was generated from the following file:

• src/sthread/sthread.h

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