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author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2016-06-13 10:17:20 +0200 |
---|---|---|
committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2016-06-13 15:58:25 +0200 |
commit | ee64baf4ea3b7affb7e325bb3d188515ec4bb66e (patch) | |
tree | e99c82a4efe621de6d6683fc5af366aef5d807ca | |
parent | s390/uaccess: fix whitespace damage (diff) | |
download | linux-ee64baf4ea3b7affb7e325bb3d188515ec4bb66e.tar.xz linux-ee64baf4ea3b7affb7e325bb3d188515ec4bb66e.zip |
s390/uaccess: use __builtin_expect for get_user/put_user
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 a76cf66e948a ("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>
-rw-r--r-- | arch/s390/include/asm/uaccess.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h index e0900ddf91dd..2ea7f3208cd2 100644 --- a/arch/s390/include/asm/uaccess.h +++ b/arch/s390/include/asm/uaccess.h @@ -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) \ |