pm_qos_requirement-fix
Signed-off-by: John Kacur <jkacur at gmail dot com>

Add a raw spinlock for the target value.


Index: linux-2.6.26.1-rt1.jk/kernel/pm_qos_params.c
===================================================================
--- linux-2.6.26.1-rt1.jk.orig/kernel/pm_qos_params.c
+++ linux-2.6.26.1-rt1.jk/kernel/pm_qos_params.c
@@ -111,6 +111,7 @@ static struct pm_qos_object *pm_qos_arra
 };
 
 static DEFINE_SPINLOCK(pm_qos_lock);
+static DEFINE_RAW_SPINLOCK(pm_qos_rawlock);
 
 static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
 		size_t count, loff_t *f_pos);
@@ -149,13 +150,15 @@ static void update_target(int target)
 		extreme_value = pm_qos_array[target]->comparitor(
 				extreme_value, node->value);
 	}
+	spin_unlock_irqrestore(&pm_qos_lock, flags);
+	spin_lock_irqsave(&pm_qos_rawlock, flags);
 	if (pm_qos_array[target]->target_value != extreme_value) {
 		call_notifier = 1;
 		pm_qos_array[target]->target_value = extreme_value;
 		pr_debug(KERN_ERR "new target for qos %d is %d\n", target,
 			pm_qos_array[target]->target_value);
 	}
-	spin_unlock_irqrestore(&pm_qos_lock, flags);
+	spin_unlock_irqrestore(&pm_qos_rawlock, flags);
 
 	if (call_notifier)
 		blocking_notifier_call_chain(pm_qos_array[target]->notifiers,
@@ -195,9 +198,9 @@ int pm_qos_requirement(int pm_qos_class)
 	int ret_val;
 	unsigned long flags;
 
-	spin_lock_irqsave(&pm_qos_lock, flags);
+	spin_lock_irqsave(&pm_qos_rawlock, flags);
 	ret_val = pm_qos_array[pm_qos_class]->target_value;
-	spin_unlock_irqrestore(&pm_qos_lock, flags);
+	spin_unlock_irqrestore(&pm_qos_rawlock, flags);
 
 	return ret_val;
 }