[PATCH] 2.4.18-pre7 Can't use spin_lock_* with wait_queue_head_t object.
There is code in sched.c that uses the spin_lock_* interfaces to acquire and
release the lock in the wait_queue_head_t embedded in the struct completion.
This is wrong and causes the system to OPPs on startup when compiled with
wait.h:USE_RW_WAIT_QUEUE_SPINLOCK set to 1. The patch below changes the
spin_lock_* calls to wq_write_lock_*.
--
Bob Miller Email: [email protected]
Open Software Development Lab Phone: 503.626.2455 Ext. 17
diff -ru linux.2.4.18-pre7-orig/include/linux/wait.h linux.2.4.18-pre7/include/linux/wait.h
--- linux.2.4.18-pre7-orig/include/linux/wait.h Fri Feb 1 14:56:06 2002
+++ linux.2.4.18-pre7/include/linux/wait.h Mon Feb 4 09:23:29 2002
@@ -58,6 +58,7 @@
# define wq_read_unlock read_unlock
# define wq_write_lock_irq write_lock_irq
# define wq_write_lock_irqsave write_lock_irqsave
+# define wq_write_unlock_irq write_unlock_irq
# define wq_write_unlock_irqrestore write_unlock_irqrestore
# define wq_write_unlock write_unlock
#else
@@ -70,6 +71,7 @@
# define wq_read_unlock_irqrestore spin_unlock_irqrestore
# define wq_write_lock_irq spin_lock_irq
# define wq_write_lock_irqsave spin_lock_irqsave
+# define wq_write_unlock_irq spin_unlock_irq
# define wq_write_unlock_irqrestore spin_unlock_irqrestore
# define wq_write_unlock spin_unlock
#endif
diff -ru linux.2.4.18-pre7-orig/kernel/sched.c linux.2.4.18-pre7/kernel/sched.c
--- linux.2.4.18-pre7-orig/kernel/sched.c Fri Feb 1 14:56:05 2002
+++ linux.2.4.18-pre7/kernel/sched.c Fri Feb 1 15:17:38 2002
@@ -761,15 +761,15 @@
{
unsigned long flags;
- spin_lock_irqsave(&x->wait.lock, flags);
+ wq_write_lock_irqsave(&x->wait.lock, flags);
x->done++;
__wake_up_common(&x->wait, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 1, 0);
- spin_unlock_irqrestore(&x->wait.lock, flags);
+ wq_write_unlock_irqrestore(&x->wait.lock, flags);
}
void wait_for_completion(struct completion *x)
{
- spin_lock_irq(&x->wait.lock);
+ wq_write_lock_irq(&x->wait.lock);
if (!x->done) {
DECLARE_WAITQUEUE(wait, current);
@@ -777,14 +777,14 @@
__add_wait_queue_tail(&x->wait, &wait);
do {
__set_current_state(TASK_UNINTERRUPTIBLE);
- spin_unlock_irq(&x->wait.lock);
+ wq_write_unlock_irq(&x->wait.lock);
schedule();
- spin_lock_irq(&x->wait.lock);
+ wq_write_lock_irq(&x->wait.lock);
} while (!x->done);
__remove_wait_queue(&x->wait, &wait);
}
x->done--;
- spin_unlock_irq(&x->wait.lock);
+ wq_write_unlock_irq(&x->wait.lock);
}
#define SLEEP_ON_VAR \