Files
zinnia/core/spin.c
T

25 lines
586 B
C

#include <zinnia/atomic.h>
#include <zinnia/irq.h>
#include <zinnia/spin.h>
#include <arch/cpu.h>
void spin_init(struct spinlock* spin) {
spin->next = 0;
spin->owner = 0;
}
void spin_lock(struct spinlock* spin) {
irq_lock();
uint32_t my = atomic_fetch_add(&spin->next, 1, ATOMIC_RELAXED);
while (atomic_load(&spin->owner, ATOMIC_ACQUIRE) != my) {
arch_cpu_pause();
}
}
void spin_unlock(struct spinlock* spin) {
uint32_t val = atomic_load(&spin->owner, ATOMIC_RELAXED);
atomic_store(&spin->owner, val + 1, ATOMIC_RELEASE);
irq_unlock();
}