mscp/src/atomic.h

#ifndef _ATOMIC_H_
#define _ATOMIC_H_

#include <stdlib.h>
#include <pthread.h>
#include <util.h>

typedef int refcnt;

static inline void refcnt_inc(refcnt *cnt)
{
	__sync_add_and_fetch(cnt, 1);
}

static inline refcnt refcnt_dec(refcnt *cnt)
{
	return __sync_sub_and_fetch(cnt, 1);
}


typedef pthread_mutex_t lock;

static inline void lock_init(lock *l)
{
	pthread_mutex_init(l, NULL);
}

static inline void lock_acquire(lock *l)
{
	int ret = pthread_mutex_lock(l);
	if (ret < 0) {
		switch (ret) {
		case EINVAL:
			pr_err("invalid mutex\n");
			exit(1);
		case EDEADLK:
			pr_err("a deadlock would occur\n");
			exit(1);
		}
	}
}

static inline void lock_release(lock *l)
{
	int ret = pthread_mutex_unlock(l);
	if (ret < 0) {
		switch (ret) {
		case EINVAL:
			pr_err("invalid mutex\n");
			exit(1);
		case EPERM:
			pr_err("this thread does not hold this mutex\n");
			exit(1);
		}
	}
}

static inline void lock_release_via_cleanup(void *l)
{
	lock_release(l);
}

#define LOCK_ACQUIRE_THREAD(l)				\
		lock_acquire(l);			\
		pthread_cleanup_push(lock_release_via_cleanup, l)


#define LOCK_RELEASE_THREAD() \
	pthread_cleanup_pop(1)

#endif /* _ATOMIC_H_ */