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 <heiko.carstens@de.ibm.com>
This commit is contained in:
Heiko Carstens 2013-09-05 13:26:17 +02:00
parent 491f6f8e5f
commit efc1d23b3d
2 changed files with 6 additions and 0 deletions

View File

@ -93,6 +93,7 @@ config S390
select ARCH_INLINE_WRITE_UNLOCK_IRQ
select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
select ARCH_SAVE_PAGE_KEYS if HIBERNATION
select ARCH_USE_CMPXCHG_LOCKREF
select ARCH_WANT_IPC_PARSE_VERSION
select BUILDTIME_EXTABLE_SORT
select CLONE_BACKWARDS2

View File

@ -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;