From efc1d23b3d9af8cbff9f26677d67fb9c1b9cb792 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Thu, 5 Sep 2013 13:26:17 +0200 Subject: s390: enable ARCH_USE_CMPXCHG_LOCKREF Enable ARCH_USE_CMPXCHG_LOCKREF since it shows performance improvements with Linus' simple stat() test case of up to 50% on a 30 cpu system. Signed-off-by: Heiko Carstens --- arch/s390/include/asm/spinlock.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/s390/include/asm/spinlock.h') diff --git a/arch/s390/include/asm/spinlock.h b/arch/s390/include/asm/spinlock.h index 701fe8c59e1..83e5d216105 100644 --- a/arch/s390/include/asm/spinlock.h +++ b/arch/s390/include/asm/spinlock.h @@ -44,6 +44,11 @@ extern void arch_spin_lock_wait_flags(arch_spinlock_t *, unsigned long flags); extern int arch_spin_trylock_retry(arch_spinlock_t *); extern void arch_spin_relax(arch_spinlock_t *lock); +static inline int arch_spin_value_unlocked(arch_spinlock_t lock) +{ + return lock.owner_cpu == 0; +} + static inline void arch_spin_lock(arch_spinlock_t *lp) { int old; -- cgit v1.2.3-70-g09d2