From: Yong Zhang <yong.zhang@xxxxxxxxxxxxx> 1) call_function.lock used in smp_call_function_many() is just to protect call_function.queue and &data->refs, cpu_online_mask is outside of the lock. And it's not necessary to protect cpu_online_mask, because data->cpumask is pre-calculate and even if a cpu is brougt up when calling arch_send_call_function_ipi_mask(), it's harmless because validation test in generic_smp_call_function_interrupt() will take care of it. 2) For cpu down issue, stop_machine() will guarantee that no concurrent smp_call_fuction() is processing. Signed-off-by: Yong Zhang <yong.zhang0@xxxxxxxxx> Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Cc: linux390@xxxxxxxxxx Cc: linux-s390@xxxxxxxxxxxxxxx --- arch/s390/kernel/smp.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 647ba94..14c8a08 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -716,9 +716,7 @@ static void __cpuinit smp_start_secondary(void *cpuvoid) init_cpu_vtimer(); pfault_init(); notify_cpu_starting(smp_processor_id()); - ipi_call_lock(); set_cpu_online(smp_processor_id(), true); - ipi_call_unlock(); local_irq_enable(); /* cpu_idle will call schedule for us */ cpu_idle(); -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
