[PATCH] s390: spinlock fixes

Remove useless spin_retry_counter and fix compilation for UP kernels.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/s390/lib/Makefile

@@ -4,5 +4,6 @@
 
 EXTRA_AFLAGS := -traditional
 
-lib-y += delay.o string.o spinlock.o
+lib-y += delay.o string.o
 lib-y += $(if $(CONFIG_64BIT),uaccess64.o,uaccess.o)
+lib-$(CONFIG_SMP) += spinlock.o

arch/s390/lib/spinlock.c

@@ -13,7 +13,6 @@
 #include <linux/init.h>
 #include <asm/io.h>
 
-atomic_t spin_retry_counter;
 int spin_retry = 1000;
 
 /**
@@ -45,7 +44,6 @@ _raw_spin_lock_wait(raw_spinlock_t *lp, unsigned int pc)
 			_diag44();
 			count = spin_retry;
 		}
-		atomic_inc(&spin_retry_counter);
 		if (_raw_compare_and_swap(&lp->lock, 0, pc) == 0)
 			return;
 	}
@@ -58,7 +56,6 @@ _raw_spin_trylock_retry(raw_spinlock_t *lp, unsigned int pc)
 	int count = spin_retry;
 
 	while (count-- > 0) {
-		atomic_inc(&spin_retry_counter);
 		if (_raw_compare_and_swap(&lp->lock, 0, pc) == 0)
 			return 1;
 	}
@@ -77,7 +74,6 @@ _raw_read_lock_wait(raw_rwlock_t *rw)
 			_diag44();
 			count = spin_retry;
 		}
-		atomic_inc(&spin_retry_counter);
 		old = rw->lock & 0x7fffffffU;
 		if (_raw_compare_and_swap(&rw->lock, old, old + 1) == old)
 			return;
@@ -92,7 +88,6 @@ _raw_read_trylock_retry(raw_rwlock_t *rw)
 	int count = spin_retry;
 
 	while (count-- > 0) {
-		atomic_inc(&spin_retry_counter);
 		old = rw->lock & 0x7fffffffU;
 		if (_raw_compare_and_swap(&rw->lock, old, old + 1) == old)
 			return 1;
@@ -111,7 +106,6 @@ _raw_write_lock_wait(raw_rwlock_t *rw)
 			_diag44();
 			count = spin_retry;
 		}
-		atomic_inc(&spin_retry_counter);
 		if (_raw_compare_and_swap(&rw->lock, 0, 0x80000000) == 0)
 			return;
 	}
@@ -124,7 +118,6 @@ _raw_write_trylock_retry(raw_rwlock_t *rw)
 	int count = spin_retry;
 
 	while (count-- > 0) {
-		atomic_inc(&spin_retry_counter);
 		if (_raw_compare_and_swap(&rw->lock, 0, 0x80000000) == 0)
 			return 1;
 	}

kernel/sysctl.c

@@ -648,7 +648,7 @@ static ctl_table kern_table[] = {
 		.mode		= 0644,
 		.proc_handler	= &proc_dointvec,
 	},
-#if defined(CONFIG_S390)
+#if defined(CONFIG_S390) && defined(CONFIG_SMP)
 	{
 		.ctl_name	= KERN_SPIN_RETRY,
 		.procname	= "spin_retry",