[PATCH 3/3] pm_qos: only schedule work when in interrupt context

[florian@mickler.org]

With this patch we only schedule the work when in interrupt context.

Before update_request was callable from interrupt-context there was a
1:1 relation between a change in the request-value and a notification.
This patch restores that behaviour for all constraints that have update_request
never called from interrupt context.

The notifier mutex serializes calls to blocking_notifier_call_chain, so
that we are serialized against any pending or currently executing notification.

Signed-off-by: Florian Mickler <florian@mickler.org>
---
 kernel/pm_qos_params.c |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
index 9346906..c06cae9 100644
--- a/kernel/pm_qos_params.c
+++ b/kernel/pm_qos_params.c
@@ -152,11 +152,15 @@ static s32 min_compare(s32 v1, s32 v2)
 static void pm_qos_call_notifiers(struct pm_qos_object *o,
 				  unsigned long curr_value)
 {
-	schedule_work(&o->notify);
-
 	if (o->atomic_notifiers)
 		atomic_notifier_call_chain(o->atomic_notifiers,
-					   curr_value, NULL);
+				(unsigned long) curr_value, NULL);
+
+	if (in_interrupt()) 
+		schedule_work(&o->notify);
+	else 
+		blocking_notifier_call_chain(o->blocking_notifiers, 
+				(unsigned long) curr_value, NULL);
 }
 
 static void update_notify(struct work_struct *work)
-- 
1.7.1