1 files changed, 58 insertions, 0 deletions
diff --git a/arch/x86/kernel/apic/hw_nmi.c b/arch/x86/kernel/apic/hw_nmi.c
new file mode 100644
index 000000000..d1fc62a67
--- /dev/null
+++ b/arch/x86/kernel/apic/hw_nmi.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  HW NMI watchdog support
+ *
+ *  started by Don Zickus, Copyright (C) 2010 Red Hat, Inc.
+ *
+ *  Arch specific calls to support NMI watchdog
+ *
+ *  Bits copied from original nmi.c file
+ *
+ */
+#include <asm/apic.h>
+#include <asm/nmi.h>
+
+#include <linux/cpumask.h>
+#include <linux/kdebug.h>
+#include <linux/notifier.h>
+#include <linux/kprobes.h>
+#include <linux/nmi.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+
+#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
+u64 hw_nmi_get_sample_period(int watchdog_thresh)
+{
+	return (u64)(cpu_khz) * 1000 * watchdog_thresh;
+}
+#endif
+
+#ifdef arch_trigger_cpumask_backtrace
+static void nmi_raise_cpu_backtrace(cpumask_t *mask)
+{
+	apic->send_IPI_mask(mask, NMI_VECTOR);
+}
+
+void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
+{
+	nmi_trigger_cpumask_backtrace(mask, exclude_self,
+				      nmi_raise_cpu_backtrace);
+}
+
+static int nmi_cpu_backtrace_handler(unsigned int cmd, struct pt_regs *regs)
+{
+	if (nmi_cpu_backtrace(regs))
+		return NMI_HANDLED;
+
+	return NMI_DONE;
+}
+NOKPROBE_SYMBOL(nmi_cpu_backtrace_handler);
+
+static int __init register_nmi_cpu_backtrace_handler(void)
+{
+	register_nmi_handler(NMI_LOCAL, nmi_cpu_backtrace_handler,
+				0, "arch_bt");
+	return 0;
+}
+early_initcall(register_nmi_cpu_backtrace_handler);
+#endif