spinlock.h

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#ifndef UTILS_SPINLOCK_HEADER
#define UTILS_SPINLOCK_HEADER
#include <stdint.h>
#include "utils/arax_assert.h"
 
#if __x86_64__
typedef volatile uint64_t utils_spinlock;
 
#else /* if __x86_64__ */
typedef volatile uint32_t utils_spinlock;
 
#endif /* if __x86_64__ */

static inline void utils_spinlock_init(utils_spinlock *lock)
{
    *lock = 0;
}

static inline void utils_spinlock_lock(utils_spinlock *lock)
{
    do {
        while (*lock)
            ;  /* Maybe add relax()? */
        if (__sync_bool_compare_and_swap(lock, 0, 1) )
            break;  /* We got it */
    } while (1);    /* Try again */
}

static inline void utils_spinlock_unlock(utils_spinlock *lock)
{
    arax_assert(*lock); /* Attempting to unlock twice */
    __sync_fetch_and_and(lock, 0);
}
 
#endif /* ifndef UTILS_SPINLOCK_HEADER */