libmetal
spinlock.h
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30 
31 /*
32  * @file spinlock.h
33  * @brief Spinlock primitives for libmetal.
34  */
35 
36 #ifndef __METAL_SPINLOCK__H__
37 #define __METAL_SPINLOCK__H__
38 
39 #include "metal/atomic.h"
40 #include "metal/cpu.h"
41 
42 #ifdef __cplusplus
43 extern "C" {
44 #endif
45 
50 };
51 
53 #define METAL_SPINLOCK_INIT {ATOMIC_VAR_INIT(0)}
54 
59 static inline void metal_spinlock_init(struct metal_spinlock *slock)
60 {
61  atomic_store(&slock->v, 0);
62 }
63 
69 static inline void metal_spinlock_acquire(struct metal_spinlock *slock)
70 {
71  while (atomic_flag_test_and_set(&slock->v)) {
73  }
74 }
75 
81 static inline void metal_spinlock_release(struct metal_spinlock *slock)
82 {
83  atomic_flag_clear(&slock->v);
84 }
85 
88 #ifdef __cplusplus
89 }
90 #endif
91 
92 #endif /* __METAL_SPINLOCK__H__ */
Definition: spinlock.h:48
static void metal_spinlock_release(struct metal_spinlock *slock)
Release a previously acquired spinlock.
Definition: spinlock.h:81
#define metal_cpu_yield()
Definition: cpu.h:39
static void metal_spinlock_init(struct metal_spinlock *slock)
Initialize a libmetal spinlock.
Definition: spinlock.h:59
static void metal_spinlock_acquire(struct metal_spinlock *slock)
Acquire a spinlock.
Definition: spinlock.h:69
#define atomic_flag_test_and_set(FLAG)
Definition: atomic.h:67
#define atomic_flag_clear(FLAG)
Definition: atomic.h:71
#define atomic_store(OBJ, VAL)
Definition: atomic.h:79
atomic_int v
Definition: spinlock.h:49
int atomic_int
Definition: atomic.h:48