41 lines
532 B
C
41 lines
532 B
C
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#include <sync.h>
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void spinlock_init(spinlock_t* lock)
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{
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lock->locked = 0;
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}
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static inline int atomic_xchg(volatile int* addr, int newval)
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{
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int result;
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asm volatile (
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"xchg %0, %1"
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: "=r"(result), "+m"(*addr)
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: "0"(newval)
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: "memory"
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);
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return result;
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}
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void spin_lock(spinlock_t* lock)
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{
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while (atomic_xchg(&lock->locked, 1))
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{
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while (lock->locked)
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{
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asm volatile("pause");
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}
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}
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}
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void spin_unlock(spinlock_t* lock)
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{
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__atomic_clear(&lock->locked, __ATOMIC_RELEASE);
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}
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