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Diffstat (limited to 'arch/arm/kernel/smp.c')
-rw-r--r--arch/arm/kernel/smp.c35
1 files changed, 33 insertions, 2 deletions
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 3d6b7821c..48185a773 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -21,6 +21,7 @@
#include <linux/cpu.h>
#include <linux/seq_file.h>
#include <linux/irq.h>
+#include <linux/nmi.h>
#include <linux/percpu.h>
#include <linux/clockchips.h>
#include <linux/completion.h>
@@ -72,6 +73,7 @@ enum ipi_msg_type {
IPI_CPU_STOP,
IPI_IRQ_WORK,
IPI_COMPLETION,
+ IPI_CPU_BACKTRACE = 15,
};
static DECLARE_COMPLETION(cpu_running);
@@ -175,13 +177,26 @@ static int platform_cpu_disable(unsigned int cpu)
if (smp_ops.cpu_disable)
return smp_ops.cpu_disable(cpu);
+ return 0;
+}
+
+int platform_can_hotplug_cpu(unsigned int cpu)
+{
+ /* cpu_die must be specified to support hotplug */
+ if (!smp_ops.cpu_die)
+ return 0;
+
+ if (smp_ops.cpu_can_disable)
+ return smp_ops.cpu_can_disable(cpu);
+
/*
* By default, allow disabling all CPUs except the first one,
* since this is special on a lot of platforms, e.g. because
* of clock tick interrupts.
*/
- return cpu == 0 ? -EPERM : 0;
+ return cpu != 0;
}
+
/*
* __cpu_disable runs on the processor to be shutdown.
*/
@@ -253,7 +268,7 @@ void __cpu_die(unsigned int cpu)
* of the other hotplug-cpu capable cores, so presumably coming
* out of idle fixes this.
*/
-void __ref cpu_die(void)
+void arch_cpu_idle_dead(void)
{
unsigned int cpu = smp_processor_id();
@@ -630,6 +645,12 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
irq_exit();
break;
+ case IPI_CPU_BACKTRACE:
+ irq_enter();
+ nmi_cpu_backtrace(regs);
+ irq_exit();
+ break;
+
default:
pr_crit("CPU%u: Unknown IPI message 0x%x\n",
cpu, ipinr);
@@ -724,3 +745,13 @@ static int __init register_cpufreq_notifier(void)
core_initcall(register_cpufreq_notifier);
#endif
+
+static void raise_nmi(cpumask_t *mask)
+{
+ smp_cross_call(mask, IPI_CPU_BACKTRACE);
+}
+
+void arch_trigger_all_cpu_backtrace(bool include_self)
+{
+ nmi_trigger_all_cpu_backtrace(include_self, raise_nmi);
+}