[S390] implement interrupt-enabling rwlocks
arch backend for f5f7eac41db827a47b2163330eecd7bb55ae9f12
"Allow rwlocks to re-enable interrupts".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/spinlock.h b/arch/s390/include/asm/spinlock.h
index f3861b0..c9af0d19 100644
--- a/arch/s390/include/asm/spinlock.h
+++ b/arch/s390/include/asm/spinlock.h
@@ -122,8 +122,10 @@
#define __raw_write_can_lock(x) ((x)->lock == 0)
extern void _raw_read_lock_wait(raw_rwlock_t *lp);
+extern void _raw_read_lock_wait_flags(raw_rwlock_t *lp, unsigned long flags);
extern int _raw_read_trylock_retry(raw_rwlock_t *lp);
extern void _raw_write_lock_wait(raw_rwlock_t *lp);
+extern void _raw_write_lock_wait_flags(raw_rwlock_t *lp, unsigned long flags);
extern int _raw_write_trylock_retry(raw_rwlock_t *lp);
static inline void __raw_read_lock(raw_rwlock_t *rw)
@@ -134,6 +136,14 @@
_raw_read_lock_wait(rw);
}
+static inline void __raw_read_lock_flags(raw_rwlock_t *rw, unsigned long flags)
+{
+ unsigned int old;
+ old = rw->lock & 0x7fffffffU;
+ if (_raw_compare_and_swap(&rw->lock, old, old + 1) != old)
+ _raw_read_lock_wait_flags(rw, flags);
+}
+
static inline void __raw_read_unlock(raw_rwlock_t *rw)
{
unsigned int old, cmp;
@@ -151,6 +161,12 @@
_raw_write_lock_wait(rw);
}
+static inline void __raw_write_lock_flags(raw_rwlock_t *rw, unsigned long flags)
+{
+ if (unlikely(_raw_compare_and_swap(&rw->lock, 0, 0x80000000) != 0))
+ _raw_write_lock_wait_flags(rw, flags);
+}
+
static inline void __raw_write_unlock(raw_rwlock_t *rw)
{
_raw_compare_and_swap(&rw->lock, 0x80000000, 0);
@@ -172,9 +188,6 @@
return _raw_write_trylock_retry(rw);
}
-#define __raw_read_lock_flags(lock, flags) __raw_read_lock(lock)
-#define __raw_write_lock_flags(lock, flags) __raw_write_lock(lock)
-
#define _raw_read_relax(lock) cpu_relax()
#define _raw_write_relax(lock) cpu_relax()
diff --git a/arch/s390/lib/spinlock.c b/arch/s390/lib/spinlock.c
index e41f400..f7e0d30 100644
--- a/arch/s390/lib/spinlock.c
+++ b/arch/s390/lib/spinlock.c
@@ -124,6 +124,27 @@
}
EXPORT_SYMBOL(_raw_read_lock_wait);
+void _raw_read_lock_wait_flags(raw_rwlock_t *rw, unsigned long flags)
+{
+ unsigned int old;
+ int count = spin_retry;
+
+ local_irq_restore(flags);
+ while (1) {
+ if (count-- <= 0) {
+ _raw_yield();
+ count = spin_retry;
+ }
+ if (!__raw_read_can_lock(rw))
+ continue;
+ old = rw->lock & 0x7fffffffU;
+ local_irq_disable();
+ if (_raw_compare_and_swap(&rw->lock, old, old + 1) == old)
+ return;
+ }
+}
+EXPORT_SYMBOL(_raw_read_lock_wait_flags);
+
int _raw_read_trylock_retry(raw_rwlock_t *rw)
{
unsigned int old;
@@ -157,6 +178,25 @@
}
EXPORT_SYMBOL(_raw_write_lock_wait);
+void _raw_write_lock_wait_flags(raw_rwlock_t *rw, unsigned long flags)
+{
+ int count = spin_retry;
+
+ local_irq_restore(flags);
+ while (1) {
+ if (count-- <= 0) {
+ _raw_yield();
+ count = spin_retry;
+ }
+ if (!__raw_write_can_lock(rw))
+ continue;
+ local_irq_disable();
+ if (_raw_compare_and_swap(&rw->lock, 0, 0x80000000) == 0)
+ return;
+ }
+}
+EXPORT_SYMBOL(_raw_write_lock_wait_flags);
+
int _raw_write_trylock_retry(raw_rwlock_t *rw)
{
int count = spin_retry;