From d232ed0c0eee44a5d3bbc4f21f136a303e77c34d Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Sun, 2 Mar 2014 13:09:47 +0100 Subject: futex: Allow architectures to skip futex_atomic_cmpxchg_inatomic() test commit 03b8c7b623c80af264c4c8d6111e5c6289933666 upstream. If an architecture has futex_atomic_cmpxchg_inatomic() implemented and there is no runtime check necessary, allow to skip the test within futex_init(). This allows to get rid of some code which would always give the same result, and also allows the compiler to optimize a couple of if statements away. Signed-off-by: Heiko Carstens Cc: Finn Thain Cc: Geert Uytterhoeven Link: http://lkml.kernel.org/r/20140302120947.GA3641@osiris Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- include/linux/futex.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include') diff --git a/include/linux/futex.h b/include/linux/futex.h index b0d95cac826..6435f46d6e1 100644 --- a/include/linux/futex.h +++ b/include/linux/futex.h @@ -55,7 +55,11 @@ union futex_key { #ifdef CONFIG_FUTEX extern void exit_robust_list(struct task_struct *curr); extern void exit_pi_state_list(struct task_struct *curr); +#ifdef CONFIG_HAVE_FUTEX_CMPXCHG +#define futex_cmpxchg_enabled 1 +#else extern int futex_cmpxchg_enabled; +#endif #else static inline void exit_robust_list(struct task_struct *curr) { -- cgit v1.2.3-18-g5258