Read-Write Mutex

Read-Write Mutex. More...

Data Structures
struct	rwmutex_t
	Read-Write Mutex structure. More...

Macros
#define	RWMUTEX_READ_SCOPE(mutex)
	Acquires a rwmutex for reading for the reminder of the current scope.
#define	RWMUTEX_WRITE_SCOPE(mutex)
	Acquires a rwmutex for writing for the reminder of the current scope.

Functions
void	rwmutex_init (rwmutex_t *mtx)
	Initializes a rwmutex.
void	rwmutex_deinit (rwmutex_t *mtx)
	Deinitializes a rwmutex.
void	rwmutex_read_acquire (rwmutex_t *mtx)
	Acquires a rwmutex for reading, blocking until it is available.
uint64_t	rwmutex_read_try_acquire (rwmutex_t *mtx)
	Tries to acquire a rwmutex for reading.
void	rwmutex_read_release (rwmutex_t *mtx)
	Releases a rwmutex from reading.
void	rwmutex_write_acquire (rwmutex_t *mtx)
	Acquires a rwmutex for writing, blocking until it is available.
uint64_t	rwmutex_write_try_acquire (rwmutex_t *mtx)
	Tries to acquire a rwmutex for writing.
void	rwmutex_write_release (rwmutex_t *mtx)
	Releases a rwmutex from writing.
static void	rwmutex_read_cleanup (rwmutex_t **mutex)
static void	rwmutex_write_cleanup (rwmutex_t **mutex)

Detailed Description

Read-Write Mutex.

Macro Definition Documentation

RWMUTEX_READ_SCOPE

#define RWMUTEX_READ_SCOPE

(

mutex

)

Value:

    __attribute__((cleanup(rwmutex_read_cleanup))) rwmutex_t* CONCAT(rm, __COUNTER__) = (mutex); \
    rwmutex_read_acquire((mutex))

Acquires a rwmutex for reading for the reminder of the current scope.

Parameters

mutex

Pointer to the rwmutex to acquire.

Definition at line 21 of file rwmutex.h.

RWMUTEX_WRITE_SCOPE

#define RWMUTEX_WRITE_SCOPE

(

mutex

)

Value:

    __attribute__((cleanup(rwmutex_write_cleanup))) rwmutex_t* CONCAT(wm, __COUNTER__) = (mutex); \
    rwmutex_write_acquire((mutex))

Acquires a rwmutex for writing for the reminder of the current scope.

Parameters

mutex

Pointer to the rwmutex to acquire.

Definition at line 30 of file rwmutex.h.

Function Documentation

rwmutex_deinit()

void rwmutex_deinit

(

rwmutex_t *

mtx

)

Deinitializes a rwmutex.

Parameters

mtx	Pointer to the rwmutex to deinitialize.

Definition at line 20 of file rwmutex.c.

References rwmutex_t::activeReaders, assert, rwmutex_t::hasWriter, rwmutex_t::lock, LOCK_SCOPE, rwmutex_t::readerQueue, wait_queue_deinit(), rwmutex_t::waitingWriters, and rwmutex_t::writerQueue.

Referenced by socket_free(), and socket_new().

rwmutex_init()

void rwmutex_init

(

rwmutex_t *

mtx

)

Initializes a rwmutex.

Parameters

mtx	Pointer to the rwmutex to initialize.

Definition at line 10 of file rwmutex.c.

References rwmutex_t::activeReaders, rwmutex_t::hasWriter, rwmutex_t::lock, lock_init(), rwmutex_t::readerQueue, wait_queue_init(), rwmutex_t::waitingWriters, and rwmutex_t::writerQueue.

Referenced by socket_new().

rwmutex_read_acquire()

void rwmutex_read_acquire

(

rwmutex_t *

mtx

)

Acquires a rwmutex for reading, blocking until it is available.

Parameters

mtx	Pointer to the rwmutex to acquire.

Definition at line 30 of file rwmutex.c.

References rwmutex_t::activeReaders, ERR, rwmutex_t::hasWriter, rwmutex_t::lock, LOCK_SCOPE, NULL, rwmutex_t::readerQueue, WAIT_BLOCK_LOCK, and rwmutex_t::waitingWriters.

rwmutex_read_cleanup()

static void rwmutex_read_cleanup ( rwmutex_t **  mutex )

inlinestatic

Definition at line 116 of file rwmutex.h.

References mutex, and rwmutex_read_release().

rwmutex_read_release()

void rwmutex_read_release

(

rwmutex_t *

mtx

)

Releases a rwmutex from reading.

Parameters

mtx	Pointer to the rwmutex to release.

Definition at line 67 of file rwmutex.c.

References rwmutex_t::activeReaders, assert, EOK, rwmutex_t::lock, LOCK_SCOPE, NULL, wait_unblock(), rwmutex_t::waitingWriters, and rwmutex_t::writerQueue.

Referenced by rwmutex_read_cleanup().

rwmutex_read_try_acquire()

uint64_t rwmutex_read_try_acquire

(

rwmutex_t *

mtx

)

Tries to acquire a rwmutex for reading.

If the rwmutex is owned by another thread for writing or a writer is waiting, this function will fail with EWOULDBLOCK.

If the function succeeds, rwmutex_read_release() must be called to release the rwmutex.

Parameters

mtx	Pointer to the rwmutex to acquire.

Returns

On success, 0. On error, ERR and errno is set.

Definition at line 47 of file rwmutex.c.

References rwmutex_t::activeReaders, EINVAL, ERR, errno, EWOULDBLOCK, rwmutex_t::hasWriter, rwmutex_t::lock, LOCK_SCOPE, NULL, and rwmutex_t::waitingWriters.

rwmutex_write_acquire()

void rwmutex_write_acquire

(

rwmutex_t *

mtx

)

Acquires a rwmutex for writing, blocking until it is available.

Parameters

mtx	Pointer to the rwmutex to acquire.

Definition at line 85 of file rwmutex.c.

References rwmutex_t::activeReaders, ERR, rwmutex_t::hasWriter, rwmutex_t::lock, LOCK_SCOPE, NULL, WAIT_BLOCK_LOCK, rwmutex_t::waitingWriters, and rwmutex_t::writerQueue.

Referenced by socket_start_transition().

rwmutex_write_cleanup()

static void rwmutex_write_cleanup ( rwmutex_t **  mutex )

inlinestatic

Definition at line 121 of file rwmutex.h.

References mutex, and rwmutex_write_release().

rwmutex_write_release()

void rwmutex_write_release

(

rwmutex_t *

mtx

)

Releases a rwmutex from writing.

Parameters

mtx	Pointer to the rwmutex to release.

Definition at line 124 of file rwmutex.c.

References EOK, rwmutex_t::hasWriter, rwmutex_t::lock, LOCK_SCOPE, NULL, rwmutex_t::readerQueue, WAIT_ALL, wait_unblock(), rwmutex_t::waitingWriters, and rwmutex_t::writerQueue.

Referenced by rwmutex_write_cleanup(), socket_end_transition(), and socket_start_transition().

rwmutex_write_try_acquire()

uint64_t rwmutex_write_try_acquire

(

rwmutex_t *

mtx

)

Tries to acquire a rwmutex for writing.

If the function succeeds, rwmutex_write_release() must be called to release the rwmutex.

Parameters

mtx	Pointer to the rwmutex to acquire.

Returns

On success, 0. On error, ERR and errno is set.

Definition at line 104 of file rwmutex.c.

References rwmutex_t::activeReaders, EINVAL, ERR, errno, EWOULDBLOCK, rwmutex_t::hasWriter, rwmutex_t::lock, LOCK_SCOPE, and NULL.