[S390] smp/idle: call init_idle() before starting a new cpu

Call init_idle() which (re-)initializes the idle task structure before
it gets used on a new cpu.
That way we can also get rid of the odd preempt_enable_no_resched()
call we have in the cpu offline path within cpu_idle(). That call
prevented preempt count imbalances between cpu hotplug operations.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 8e84b5af49ba..10766be524eb 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -575,6 +575,7 @@ int __cpuinit __cpu_up(unsigned int cpu)
                 idle = c_idle.idle;
                 current_set[cpu] = c_idle.idle;
         }
+        init_idle(idle, cpu);
         if (smp_alloc_lowcore(cpu))
                 return -ENOMEM;
         do {