[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, 2 insertions, 1 deletions

diff --git a/arch/s390/include/asm/smp.h b/arch/s390/include/asm/smp.h
index edc03cb9cd79..045e009fc164 100644
--- a/arch/s390/include/asm/smp.h
+++ b/arch/s390/include/asm/smp.h
@@ -20,7 +20,6 @@ extern void machine_power_off_smp(void);
 
 extern int __cpu_disable (void);
 extern void __cpu_die (unsigned int cpu);
-extern void cpu_die (void) __attribute__ ((noreturn));
 extern int __cpu_up (unsigned int cpu);
 
 extern struct mutex smp_cpu_state_mutex;
@@ -71,8 +70,10 @@ static inline void smp_switch_to_ipl_cpu(void (*func)(void *), void *data)
 
 #ifdef CONFIG_HOTPLUG_CPU
 extern int smp_rescan_cpus(void);
+extern void __noreturn cpu_die(void);
 #else
 static inline int smp_rescan_cpus(void) { return 0; }
+static inline void cpu_die(void) { }
 #endif
 
 #endif /* __ASM_SMP_H */