[GIT PULL] scheduler fixes

[Ingo Molnar]

Linus,

Please pull the latest sched-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
sched-urgent-for-linus

   # HEAD: e117cb52bdb4d376b711bee34af6434c9e314b3b sched/deadline: Fix 
switched_from_dl() warning

Two fixes: a stop-machine preemption fix and a SCHED_DEADLINE fix.

 Thanks,

        Ingo

------------------>
Isaac J. Manjarres (1):
      stop_machine: Disable preemption when waking two stopper threads

Juri Lelli (1):
      sched/deadline: Fix switched_from_dl() warning


 kernel/sched/deadline.c | 11 ++++++++++-
 kernel/stop_machine.c   |  6 +++++-
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index fbfc3f1d368a..10c7b51c0d1f 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -2290,8 +2290,17 @@ static void switched_from_dl(struct rq *rq, struct 
task_struct *p)
        if (task_on_rq_queued(p) && p->dl.dl_runtime)
                task_non_contending(p);
 
-       if (!task_on_rq_queued(p))
+       if (!task_on_rq_queued(p)) {
+               /*
+                * Inactive timer is armed. However, p is leaving DEADLINE and
+                * might migrate away from this rq while continuing to run on
+                * some other class. We need to remove its contribution from
+                * this rq running_bw now, or sub_rq_bw (below) will complain.
+                */
+               if (p->dl.dl_non_contending)
+                       sub_running_bw(&p->dl, &rq->dl);
                sub_rq_bw(&p->dl, &rq->dl);
+       }
 
        /*
         * We cannot use inactive_task_timer() to invoke sub_running_bw()
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index f89014a2c238..1ff523dae6e2 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -270,7 +270,11 @@ static int cpu_stop_queue_two_works(int cpu1, struct 
cpu_stop_work *work1,
                goto retry;
        }
 
-       wake_up_q(&wakeq);
+       if (!err) {
+               preempt_disable();
+               wake_up_q(&wakeq);
+               preempt_enable();
+       }
 
        return err;
 }