35 lines
1.0 KiB
C
35 lines
1.0 KiB
C
// sync_primitives.c
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#include "spinlock.h"
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// Initialize the spinlock
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void spinlock_init(Spinlock *spinlock) {
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spinlock->lock = 0; // Unlocked state
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}
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// Acquire the spinlock
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void spinlock_acquire(Spinlock *spinlock) {
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int status;
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do {
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// Wait until the lock is available
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do {
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__asm__ volatile ("ldrex %0, [%1]"
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: "=&r" (status)
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: "r" (&spinlock->lock)
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: "memory");
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} while (status != 0);
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// Try to acquire the lock using strex
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__asm__ volatile ("strex %0, %2, [%1]"
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: "=&r" (status)
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: "r" (&spinlock->lock), "r" (1)
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: "memory");
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} while (status != 0); // Retry if strex failed
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}
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// Release the spinlock
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void spinlock_release(Spinlock *spinlock) {
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// Use a memory barrier to ensure proper ordering
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__asm__ volatile ("dmb" ::: "memory");
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spinlock->lock = 0; // Release the lock
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}
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