[PATCH 6/6] [RFC] alarmtimer: Deboost on nanosleep

[John Stultz <john.stultz@linaro.org>]

Example of deboosting tasks before blocking on a wakeup
source like alarmtimer based nanosleep.

With this final patch, the kernel will be able to suspend
when SCHED_STAYAWAKE flagged tasks are blocked on the alarmtimer.

CC: Rafael J. Wysocki <rjw@sisk.pl>
CC: arve@android.com
CC: markgross@thegnar.org
CC: Alan Stern <stern@rowland.harvard.edu>
CC: amit.kucheria@linaro.org
CC: farrowg@sg.ibm.com
CC: Dmitry Fink (Palm GBU) <Dmitry.Fink@palm.com>
CC: linux-pm@lists.linux-foundation.org
CC: khilman@ti.com
CC: Magnus Damm <damm@opensource.se>
CC: mjg@redhat.com 
CC: peterz@infradead.org 
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 kernel/time/alarmtimer.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 00ee80f..c855d40 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -568,9 +568,10 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp)
 	do {
 		set_current_state(TASK_INTERRUPTIBLE);
 		alarm_start(alarm, absexp, ktime_set(0, 0));
-		if (likely(alarm->data))
+		if (likely(alarm->data)) {
+			sched_deboost_task_active_count(current);
 			schedule();
-
+		}
 		alarm_cancel(alarm);
 	} while (alarm->data && !signal_pending(current));
 
-- 
1.7.3.2.146.gca209