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Diffstat (limited to 'include/asm-ia64/spinlock.h')
-rw-r--r--include/asm-ia64/spinlock.h12
1 files changed, 11 insertions, 1 deletions
diff --git a/include/asm-ia64/spinlock.h b/include/asm-ia64/spinlock.h
index 5b78611411c..0c91a76c5ea 100644
--- a/include/asm-ia64/spinlock.h
+++ b/include/asm-ia64/spinlock.h
@@ -201,6 +201,16 @@ static inline void __raw_write_unlock(raw_rwlock_t *x)
#endif /* !ASM_SUPPORTED */
-#define __raw_read_trylock(lock) generic__raw_read_trylock(lock)
+static inline int __raw_read_trylock(raw_rwlock_t *x)
+{
+ union {
+ raw_rwlock_t lock;
+ __u32 word;
+ } old, new;
+ old.lock = new.lock = *x;
+ old.lock.write_lock = new.lock.write_lock = 0;
+ ++new.lock.read_counter;
+ return (u32)ia64_cmpxchg4_acq((__u32 *)(x), new.word, old.word) == old.word;
+}
#endif /* _ASM_IA64_SPINLOCK_H */