ARM: add basic support for on-demand backtrace of other CPUs

[karo-tx-linux.git] / arch / arm / kernel / smp.c

diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 90dfbedfbfb8527b74ddcfcef125beb151f875f5..3a20c386fd33f71f383c552dcfca2b0f7bbcbc44 100644 (file)
--- 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);
@@ -630,6 +632,12 @@ 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 +732,13 @@ 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);
+}