Merge branch 'master' of /home/trondmy/kernel/linux-2.6/

[powerpc.git] / arch / s390 / lib / spinlock.c

diff --git a/arch/s390/lib/spinlock.c b/arch/s390/lib/spinlock.c
index 60f80a4..8d76403 100644 (file)
--- a/arch/s390/lib/spinlock.c
+++ b/arch/s390/lib/spinlock.c
@@ -2,8 +2,7 @@
  *  arch/s390/lib/spinlock.c
  *    Out of line spinlock code.
  *
- *  S390 version
- *    Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Copyright (C) IBM Corp. 2004, 2006
  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
  */
 
@@ -25,55 +24,80 @@ static int __init spin_retry_setup(char *str)
 }
 __setup("spin_retry=", spin_retry_setup);
 
-static inline void
-_diag44(void)
+static inline void _raw_yield(void)
 {
-#ifdef CONFIG_64BIT
        if (MACHINE_HAS_DIAG44)
-#endif
                asm volatile("diag 0,0,0x44");
 }
 
-void
-_raw_spin_lock_wait(raw_spinlock_t *lp, unsigned int pc)
+static inline void _raw_yield_cpu(int cpu)
+{
+       if (MACHINE_HAS_DIAG9C)
+               asm volatile("diag %0,0,0x9c"
+                            : : "d" (__cpu_logical_map[cpu]));
+       else
+               _raw_yield();
+}
+
+void _raw_spin_lock_wait(raw_spinlock_t *lp, unsigned int pc)
 {
        int count = spin_retry;
+       unsigned int cpu = ~smp_processor_id();
 
        while (1) {
                if (count-- <= 0) {
-                       _diag44();
+                       unsigned int owner = lp->owner_cpu;
+                       if (owner != 0)
+                               _raw_yield_cpu(~owner);
                        count = spin_retry;
                }
-               if (_raw_compare_and_swap(&lp->lock, 0, pc) == 0)
+               if (__raw_spin_is_locked(lp))
+                       continue;
+               if (_raw_compare_and_swap(&lp->owner_cpu, 0, cpu) == 0) {
+                       lp->owner_pc = pc;
                        return;
+               }
        }
 }
 EXPORT_SYMBOL(_raw_spin_lock_wait);
 
-int
-_raw_spin_trylock_retry(raw_spinlock_t *lp, unsigned int pc)
+int _raw_spin_trylock_retry(raw_spinlock_t *lp, unsigned int pc)
 {
-       int count = spin_retry;
-
-       while (count-- > 0) {
-               if (_raw_compare_and_swap(&lp->lock, 0, pc) == 0)
+       unsigned int cpu = ~smp_processor_id();
+       int count;
+
+       for (count = spin_retry; count > 0; count--) {
+               if (__raw_spin_is_locked(lp))
+                       continue;
+               if (_raw_compare_and_swap(&lp->owner_cpu, 0, cpu) == 0) {
+                       lp->owner_pc = pc;
                        return 1;
+               }
        }
        return 0;
 }
 EXPORT_SYMBOL(_raw_spin_trylock_retry);
 
-void
-_raw_read_lock_wait(raw_rwlock_t *rw)
+void _raw_spin_relax(raw_spinlock_t *lock)
+{
+       unsigned int cpu = lock->owner_cpu;
+       if (cpu != 0)
+               _raw_yield_cpu(~cpu);
+}
+EXPORT_SYMBOL(_raw_spin_relax);
+
+void _raw_read_lock_wait(raw_rwlock_t *rw)
 {
        unsigned int old;
        int count = spin_retry;
 
        while (1) {
                if (count-- <= 0) {
-                       _diag44();
+                       _raw_yield();
                        count = spin_retry;
                }
+               if (!__raw_read_can_lock(rw))
+                       continue;
                old = rw->lock & 0x7fffffffU;
                if (_raw_compare_and_swap(&rw->lock, old, old + 1) == old)
                        return;
@@ -81,13 +105,14 @@ _raw_read_lock_wait(raw_rwlock_t *rw)
 }
 EXPORT_SYMBOL(_raw_read_lock_wait);
 
-int
-_raw_read_trylock_retry(raw_rwlock_t *rw)
+int _raw_read_trylock_retry(raw_rwlock_t *rw)
 {
        unsigned int old;
        int count = spin_retry;
 
        while (count-- > 0) {
+               if (!__raw_read_can_lock(rw))
+                       continue;
                old = rw->lock & 0x7fffffffU;
                if (_raw_compare_and_swap(&rw->lock, old, old + 1) == old)
                        return 1;
@@ -96,28 +121,30 @@ _raw_read_trylock_retry(raw_rwlock_t *rw)
 }
 EXPORT_SYMBOL(_raw_read_trylock_retry);
 
-void
-_raw_write_lock_wait(raw_rwlock_t *rw)
+void _raw_write_lock_wait(raw_rwlock_t *rw)
 {
        int count = spin_retry;
 
        while (1) {
                if (count-- <= 0) {
-                       _diag44();
+                       _raw_yield();
                        count = spin_retry;
                }
+               if (!__raw_write_can_lock(rw))
+                       continue;
                if (_raw_compare_and_swap(&rw->lock, 0, 0x80000000) == 0)
                        return;
        }
 }
 EXPORT_SYMBOL(_raw_write_lock_wait);
 
-int
-_raw_write_trylock_retry(raw_rwlock_t *rw)
+int _raw_write_trylock_retry(raw_rwlock_t *rw)
 {
        int count = spin_retry;
 
        while (count-- > 0) {
+               if (!__raw_write_can_lock(rw))
+                       continue;
                if (_raw_compare_and_swap(&rw->lock, 0, 0x80000000) == 0)
                        return 1;
        }