[S390] implement interrupt-enabling rwlocks

arch backend for f5f7eac41d
"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>
This commit is contained in:
Heiko Carstens
2009-06-12 10:26:22 +02:00
committed by Martin Schwidefsky
parent 76d4e00a05
commit ce58ae6f7f
2 changed files with 56 additions and 3 deletions

View File

@@ -124,6 +124,27 @@ void _raw_read_lock_wait(raw_rwlock_t *rw)
}
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 @@ void _raw_write_lock_wait(raw_rwlock_t *rw)
}
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;