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s390/uaccess: use __builtin_expect for get_user/put_user

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We always expect that get_user and put_user return with zero. Give the
compiler a hint so it can slightly optimize the code and avoid
branches.
This is the same what x86 got with commit a76cf66e94 ("x86/uaccess:
Tell the compiler that uaccess is unlikely to fault").

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Heiko Carstens 2016-06-13 10:17:20 +02:00 committed by Martin Schwidefsky
parent b8ac5e2f4d
commit ee64baf4ea
1 changed files with 2 additions and 2 deletions
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4
arch/s390/include/asm/uaccess.h
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@ -191,7 +191,7 @@ static inline int __get_user_fn(void *x, const void __user *ptr, unsigned long s
__put_user_bad(); \
break; \
} \
__pu_err; \
__builtin_expect(__pu_err, 0); \
})
#define put_user(x, ptr) \
@ -240,7 +240,7 @@ int __put_user_bad(void) __attribute__((noreturn));
__get_user_bad(); \
break; \
} \
__gu_err; \
__builtin_expect(__gu_err, 0); \
})
#define get_user(x, ptr) \