pthread_spin_lock.c\thread\src - musl - musl - an implementation of the standard library for Linux-based systems

#include "pthread_impl.h"
#include <errno.h>
int pthread_spin_lock(pthread_spinlock_t *s)
{
	while (*(volatile int *)s || a_cas(s, 0, EBUSY)) a_spin();
	return 0;
}