diff options
| -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__ */ |
