How do I implement spinlocks in C?

How do I implement spinlocks in C?

To implement spinlocks in C, you can use atomic operations to create a lock that repeatedly checks if it's available.

Can you show me a simple code example?

Sure! Here's a basic example:

#include <stdatomic.h>
#include <stdbool.h>

typedef struct {
    atomic_bool lock;
} spinlock;

void spinlock_init(spinlock *s) {
    atomic_store(&s->lock, false);
}

void spinlock_lock(spinlock *s) {
    while (atomic_exchange(&s->lock, true)) {
        // Busy-wait
    }
}

void spinlock_unlock(spinlock *s) {
    atomic_store(&s->lock, false);
}

What are the advantages and disadvantages of using spinlocks?

Spinlocks are lightweight and can be efficient for short critical sections, but they can waste CPU cycles if held for long periods.

Are there any alternatives to spinlocks?

Yes, alternatives include mutexes and semaphores, which can be more efficient for longer wait times.