diff options
Diffstat (limited to 'arch/arm/kernel/smp.c')
| -rw-r--r-- | arch/arm/kernel/smp.c | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 3d6b7821cff8..48185a773852 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); +} |