s390/irq: count cpu restart events

Count CPU Restart events and make them visible via /proc/interrupts.
Every CPU hotplug (online) event will increase the per cpu counter.

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

3 files changed, 3 insertions, 0 deletions

diff --git a/arch/s390/include/asm/irq.h b/arch/s390/include/asm/irq.h
index c98dcac70ae0..7def77302d63 100644
--- a/arch/s390/include/asm/irq.h
+++ b/arch/s390/include/asm/irq.h
@@ -42,6 +42,7 @@ enum interruption_class {
         IRQIO_PCI,
         IRQIO_MSI,
         NMI_NMI,
+        CPU_RST,
         NR_ARCH_IRQS
 };
 
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index 5f5462447aff..9df824ea1667 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -82,6 +82,7 @@ static const struct irq_class irqclass_sub_desc[NR_ARCH_IRQS] = {
         [IRQIO_PCI]  = {.name = "PCI", .desc = "[I/O] PCI Interrupt" },
         [IRQIO_MSI]  = {.name = "MSI", .desc = "[I/O] MSI Interrupt" },
         [NMI_NMI]    = {.name = "NMI", .desc = "[NMI] Machine Check"},
+        [CPU_RST]    = {.name = "RST", .desc = "[CPU] CPU Restart"},
 };
 
 /*
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 4a36d5b5e4c9..7433a2f9e5cc 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -709,6 +709,7 @@ static void __cpuinit smp_start_secondary(void *cpuvoid)
         pfault_init();
         notify_cpu_starting(smp_processor_id());
         set_cpu_online(smp_processor_id(), true);
+        inc_irq_stat(CPU_RST);
         local_irq_enable();
         /* cpu_idle will call schedule for us */
         cpu_idle();