ck_rwlock(3) | Library Functions Manual | ck_rwlock(3) |
NAME
ck_rwlock_init
,
ck_rwlock_write_lock
,
ck_rwlock_write_unlock
,
ck_rwlock_write_trylock
,
ck_rwlock_write_downgrade
,
ck_rwlock_locked_writer
,
ck_rwlock_read_lock
,
ck_rwlock_read_trylock
,
ck_rwlock_read_unlock
,
ck_rwlock_locked_reader
,
ck_rwlock_recursive_write_lock
,
ck_rwlock_recursive_write_trylock
,
ck_rwlock_recurisve_write_unlock
,
ck_rwlock_recursive_read_lock
,
ck_rwlock_recursive_read_trylock
,
ck_rwlock_recursive_read_unlock
—
centralized write-biased reader-writer locks
LIBRARY
Concurrency Kit (libck, -lck)
SYNOPSIS
#include
<ck_rwlock.h>
ck_rwlock_t lock =
CK_RWLOCK_INITIALIZER;
void
ck_rwlock_init
(ck_rwlock_t
*lock);
void
ck_rwlock_write_lock
(ck_rwlock_t
*lock);
void
ck_rwlock_write_unlock
(ck_rwlock_t
*lock);
bool
ck_rwlock_write_trylock
(ck_rwlock_t
*lock);
bool
ck_rwlock_write_downgrade
(ck_rwlock_t
*lock);
bool
ck_rwlock_locked_writer
(ck_rwlock_t
*lock);
void
ck_rwlock_read_lock
(ck_rwlock_t
*lock);
bool
ck_rwlock_read_trylock
(ck_rwlock_t
*lock);
void
ck_rwlock_read_unlock
(ck_rwlock_t
*lock);
bool
ck_rwlock_locked_reader
(ck_rwlock_t
*lock);
ck_rwlock_recursive_t lock =
CK_RWLOCK_RECURSIVE_INITIALIZER;
void
ck_rwlock_recursive_write_lock
(ck_rwlock_recursive_t
*lock, unsigned int
tid);
bool
ck_rwlock_recursive_write_trylock
(ck_rwlock_recursive_t
*lock, unsigned int
tid);
void
ck_rwlock_recurisve_write_unlock
(ck_rwlock_recursive_t
*lock);
void
ck_rwlock_recursive_read_lock
(ck_rwlock_recursive_t
*lock);
bool
ck_rwlock_recursive_read_trylock
(ck_rwlock_recursive_t
*lock);
void
ck_rwlock_recursive_read_unlock
(ck_rwlock_recursive_t
*lock);
DESCRIPTION
This is a centralized write-biased reader-writer lock. It requires
very little space overhead and has a low latency fast path. Write-side
recursion requires usage of ck_rwlock_recursive. Read-side recursion is
disallowed. The
ck_rwlock_write_downgrade
()
function degrades the caller's write-side acquisition to a read-side
acquisition without forfeit of current critical section.
EXAMPLE
#include <ck_rwlock.h> static ck_rwlock_t lock = CK_RWLOCK_INITIALIZER; static void reader(void) { for (;;) { ck_rwlock_read_lock(&lock); /* Read-side critical section. */ ck_rwlock_read_unlock(&lock); if (ck_rwlock_read_trylock(&lock) == true) { /* Read-side critical section. */ ck_rwlock_read_unlock(&lock); } } return; } static void writer(void) { for (;;) { ck_rwlock_write_lock(&lock); /* Write-side critical section. */ ck_rwlock_write_unlock(&lock); if (ck_rwlock_write_trylock(&lock, 1) == true) { /* Write-side critical section. */ ck_rwlock_write_unlock(&lock); } } return; }
SEE ALSO
Additional information available at http://concurrencykit.org/
July 26, 2013. |