pthread_barrier_wait.c File Reference

#include "c.h"
#include "port/pg_pthread.h"

Include dependency graph for pthread_barrier_wait.c:

Go to the source code of this file.

Functions
int	pthread_barrier_init (pthread_barrier_t *barrier, const void *attr, int count)
int	pthread_barrier_wait (pthread_barrier_t *barrier)
int	pthread_barrier_destroy (pthread_barrier_t *barrier)

Function Documentation

pthread_barrier_destroy()

int pthread_barrier_destroy

(

pthread_barrier_t *

barrier

)

Definition at line 72 of file pthread_barrier_wait.c.

{
    pthread_cond_destroy(&barrier->cond);
    pthread_mutex_destroy(&barrier->mutex);
    return 0;
}

References barrier.

pthread_barrier_init()

int pthread_barrier_init	(	pthread_barrier_t *	barrier,
		const void *	attr,
		int	count
	)

Definition at line 19 of file pthread_barrier_wait.c.

{
    int         error;
 
    barrier->sense = false;
    barrier->count = count;
    barrier->arrived = 0;
    if ((error = pthread_cond_init(&barrier->cond, NULL)) != 0)
        return error;
    if ((error = pthread_mutex_init(&barrier->mutex, NULL)) != 0)
    {
        pthread_cond_destroy(&barrier->cond);
        return error;
    }
 
    return 0;
}

References barrier, error(), and pthread_mutex_init().

pthread_barrier_wait()

int pthread_barrier_wait

(

pthread_barrier_t *

barrier

)

Definition at line 38 of file pthread_barrier_wait.c.

{
    bool        initial_sense;
 
    pthread_mutex_lock(&barrier->mutex);
 
    /* We have arrived at the barrier. */
    barrier->arrived++;
    Assert(barrier->arrived <= barrier->count);
 
    /* If we were the last to arrive, release the others and return. */
    if (barrier->arrived == barrier->count)
    {
        barrier->arrived = 0;
        barrier->sense = !barrier->sense;
        pthread_mutex_unlock(&barrier->mutex);
        pthread_cond_broadcast(&barrier->cond);
 
        return PTHREAD_BARRIER_SERIAL_THREAD;
    }
 
    /* Wait for someone else to flip the sense. */
    initial_sense = barrier->sense;
    do
    {
        pthread_cond_wait(&barrier->cond, &barrier->mutex);
    } while (barrier->sense == initial_sense);
 
    pthread_mutex_unlock(&barrier->mutex);
 
    return 0;
}

References Assert, barrier, PTHREAD_BARRIER_SERIAL_THREAD, pthread_mutex_lock(), and pthread_mutex_unlock().