69 lines
2.4 KiB
C
69 lines
2.4 KiB
C
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#ifndef _KERNEL_LIBKERN_LOCK_H
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#define _KERNEL_LIBKERN_LOCK_H
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#include <libkern/c_attrs.h>
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#include <libkern/kassert.h>
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#include <libkern/log.h>
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#include <libkern/types.h>
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// #define DEBUG_SPINLOCK
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struct spinlock {
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int status;
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#ifdef DEBUG_SPINLOCK
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#endif // DEBUG_SPINLOCK
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};
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typedef struct spinlock spinlock_t;
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static ALWAYS_INLINE void spinlock_init(spinlock_t* lock)
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{
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__atomic_store_n(&lock->status, 0, __ATOMIC_RELAXED);
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}
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static ALWAYS_INLINE void spinlock_acquire(spinlock_t* lock)
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{
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int counter = 16;
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while (__atomic_exchange_n(&lock->status, 1, __ATOMIC_ACQUIRE) == 1) {
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extern bool system_can_preempt_kernel();
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if (system_can_preempt_kernel()) {
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if (!(--counter)) {
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extern void resched();
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resched();
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}
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}
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}
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}
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static ALWAYS_INLINE void spinlock_release(spinlock_t* lock)
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{
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ASSERT(lock->status == 1);
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__atomic_store_n(&lock->status, 0, __ATOMIC_RELEASE);
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}
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static ALWAYS_INLINE bool spinlock_try_acquire(spinlock_t* lock)
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{
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return !__atomic_exchange_n(&lock->status, 1, __ATOMIC_ACQUIRE);
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}
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#ifdef DEBUG_SPINLOCK
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#define spinlock_acquire(x) \
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system_disable_interrupts(); \
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extern int vmm_init_setup_finished; \
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if (vmm_init_setup_finished) { \
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log("acquire lock[%d] %s %s:%d", system_cpu_id(), #x, __FILE__, __LINE__); \
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} \
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system_enable_interrupts(); \
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spinlock_acquire(x);
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#define spinlock_release(x) \
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system_disable_interrupts(); \
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extern int vmm_init_setup_finished; \
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if (vmm_init_setup_finished) { \
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log("release lock[%d] %s %s:%d ", system_cpu_id(), #x, __FILE__, __LINE__); \
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} \
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system_enable_interrupts(); \
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spinlock_release(x);
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#endif
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#endif // _KERNEL_LIBKERN_LOCK_H
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