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>

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>
Heiko Carstens
1 parent 491f6f8e5f
Showing 2 changed files with 6 additions and 0 deletions Side-by-side Diff
arch/s390/Kconfig
arch/s390/include/asm/spinlock.h
@@ -93,6 +93,7 @@
 	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
@@ -44,6 +44,11 @@
 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;
...	...	@@ -93,6 +93,7 @@
93	93	select ARCH_INLINE_WRITE_UNLOCK_IRQ
94	94	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
95	95	select ARCH_SAVE_PAGE_KEYS if HIBERNATION
	96	+ select ARCH_USE_CMPXCHG_LOCKREF
96	97	select ARCH_WANT_IPC_PARSE_VERSION
97	98	select BUILDTIME_EXTABLE_SORT
98	99	select CLONE_BACKWARDS2
...	...	@@ -44,6 +44,11 @@
44	44	extern int arch_spin_trylock_retry(arch_spinlock_t *);
45	45	extern void arch_spin_relax(arch_spinlock_t *lock);
46	46
	47	+static inline int arch_spin_value_unlocked(arch_spinlock_t lock)
	48	+{
	49	+ return lock.owner_cpu == 0;
	50	+}
	51	+
47	52	static inline void arch_spin_lock(arch_spinlock_t *lp)
48	53	{
49	54	int old;