This source file includes following definitions.
- arch_spin_lock
- arch_spin_trylock
- arch_spin_unlock
1 #ifndef __LINUX_SPINLOCK_UP_H
2 #define __LINUX_SPINLOCK_UP_H
3
4 #ifndef __LINUX_SPINLOCK_H
5 # error "please don't include this file directly"
6 #endif
7
8 #include <asm/processor.h>
9 #include <asm/barrier.h>
10
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25
26 #ifdef CONFIG_DEBUG_SPINLOCK
27 #define arch_spin_is_locked(x) ((x)->slock == 0)
28
29 static inline void arch_spin_lock(arch_spinlock_t *lock)
30 {
31 lock->slock = 0;
32 barrier();
33 }
34
35 static inline int arch_spin_trylock(arch_spinlock_t *lock)
36 {
37 char oldval = lock->slock;
38
39 lock->slock = 0;
40 barrier();
41
42 return oldval > 0;
43 }
44
45 static inline void arch_spin_unlock(arch_spinlock_t *lock)
46 {
47 barrier();
48 lock->slock = 1;
49 }
50
51
52
53
54 #define arch_read_lock(lock) do { barrier(); (void)(lock); } while (0)
55 #define arch_write_lock(lock) do { barrier(); (void)(lock); } while (0)
56 #define arch_read_trylock(lock) ({ barrier(); (void)(lock); 1; })
57 #define arch_write_trylock(lock) ({ barrier(); (void)(lock); 1; })
58 #define arch_read_unlock(lock) do { barrier(); (void)(lock); } while (0)
59 #define arch_write_unlock(lock) do { barrier(); (void)(lock); } while (0)
60
61 #else
62 #define arch_spin_is_locked(lock) ((void)(lock), 0)
63
64 # define arch_spin_lock(lock) do { barrier(); (void)(lock); } while (0)
65 # define arch_spin_lock_flags(lock, flags) do { barrier(); (void)(lock); } while (0)
66 # define arch_spin_unlock(lock) do { barrier(); (void)(lock); } while (0)
67 # define arch_spin_trylock(lock) ({ barrier(); (void)(lock); 1; })
68 #endif
69
70 #define arch_spin_is_contended(lock) (((void)(lock), 0))
71
72 #endif