From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 23 Feb 2011 23:52:21 +0000 (+0000)
Subject: sched: Switch wait_task_inactive to schedule_hrtimeout()
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=8eb90c30e0e815a1308828352eabd03ca04229dd;p=linux-beck.git

sched: Switch wait_task_inactive to schedule_hrtimeout()

When we force thread hard and soft interrupts the startup of ksoftirqd
would hang in kthread_bind() when wait_task_inactive() calls
schedule_timeout_uninterruptible() because there is no softirq yet
which will wake us up.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20110223234956.677109139@linutronix.de>
---

diff --git a/kernel/sched.c b/kernel/sched.c
index 18d38e4ec7ba..66ca5d9ba83c 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2224,7 +2224,10 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
 		 * yield - it could be a while.
 		 */
 		if (unlikely(on_rq)) {
-			schedule_timeout_uninterruptible(1);
+			ktime_t to = ktime_set(0, NSEC_PER_SEC/HZ);
+
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			schedule_hrtimeout(&to, HRTIMER_MODE_REL);
 			continue;
 		}