diff options
Diffstat (limited to 'include/asm-sparc64')
-rw-r--r-- | include/asm-sparc64/rwsem.h | 48 |
1 files changed, 4 insertions, 44 deletions
diff --git a/include/asm-sparc64/rwsem.h b/include/asm-sparc64/rwsem.h index a1cc94f95984..4568ee4022df 100644 --- a/include/asm-sparc64/rwsem.h +++ b/include/asm-sparc64/rwsem.h | |||
@@ -46,54 +46,14 @@ extern void __up_read(struct rw_semaphore *sem); | |||
46 | extern void __up_write(struct rw_semaphore *sem); | 46 | extern void __up_write(struct rw_semaphore *sem); |
47 | extern void __downgrade_write(struct rw_semaphore *sem); | 47 | extern void __downgrade_write(struct rw_semaphore *sem); |
48 | 48 | ||
49 | static __inline__ int rwsem_atomic_update(int delta, struct rw_semaphore *sem) | 49 | static inline int rwsem_atomic_update(int delta, struct rw_semaphore *sem) |
50 | { | 50 | { |
51 | int tmp = delta; | 51 | return atomic_add_return(delta, (atomic_t *)(&sem->count)); |
52 | |||
53 | __asm__ __volatile__( | ||
54 | "1:\tlduw [%2], %%g1\n\t" | ||
55 | "add %%g1, %1, %%g7\n\t" | ||
56 | "cas [%2], %%g1, %%g7\n\t" | ||
57 | "cmp %%g1, %%g7\n\t" | ||
58 | "membar #StoreLoad | #StoreStore\n\t" | ||
59 | "bne,pn %%icc, 1b\n\t" | ||
60 | " nop\n\t" | ||
61 | "mov %%g7, %0\n\t" | ||
62 | : "=&r" (tmp) | ||
63 | : "0" (tmp), "r" (sem) | ||
64 | : "g1", "g7", "memory", "cc"); | ||
65 | |||
66 | return tmp + delta; | ||
67 | } | ||
68 | |||
69 | #define rwsem_atomic_add rwsem_atomic_update | ||
70 | |||
71 | static __inline__ __u16 rwsem_cmpxchgw(struct rw_semaphore *sem, __u16 __old, __u16 __new) | ||
72 | { | ||
73 | u32 old = (sem->count & 0xffff0000) | (u32) __old; | ||
74 | u32 new = (old & 0xffff0000) | (u32) __new; | ||
75 | u32 prev; | ||
76 | |||
77 | again: | ||
78 | __asm__ __volatile__("cas [%2], %3, %0\n\t" | ||
79 | "membar #StoreLoad | #StoreStore" | ||
80 | : "=&r" (prev) | ||
81 | : "0" (new), "r" (sem), "r" (old) | ||
82 | : "memory"); | ||
83 | |||
84 | /* To give the same semantics as x86 cmpxchgw, keep trying | ||
85 | * if only the upper 16-bits changed. | ||
86 | */ | ||
87 | if (prev != old && | ||
88 | ((prev & 0xffff) == (old & 0xffff))) | ||
89 | goto again; | ||
90 | |||
91 | return prev & 0xffff; | ||
92 | } | 52 | } |
93 | 53 | ||
94 | static __inline__ signed long rwsem_cmpxchg(struct rw_semaphore *sem, signed long old, signed long new) | 54 | static inline void rwsem_atomic_add(int delta, struct rw_semaphore *sem) |
95 | { | 55 | { |
96 | return cmpxchg(&sem->count,old,new); | 56 | atomic_add(delta, (atomic_t *)(&sem->count)); |
97 | } | 57 | } |
98 | 58 | ||
99 | #endif /* __KERNEL__ */ | 59 | #endif /* __KERNEL__ */ |