2 * HW NMI watchdog support
4 * started by Don Zickus, Copyright (C) 2010 Red Hat, Inc.
6 * Arch specific calls to support NMI watchdog
8 * Bits copied from original nmi.c file
14 #include <linux/cpumask.h>
15 #include <linux/kdebug.h>
16 #include <linux/notifier.h>
17 #include <linux/kprobes.h>
18 #include <linux/nmi.h>
19 #include <linux/init.h>
20 #include <linux/delay.h>
22 #ifdef CONFIG_HARDLOCKUP_DETECTOR
23 u64 hw_nmi_get_sample_period(int watchdog_thresh)
25 return (u64)(cpu_khz) * 1000 * watchdog_thresh;
29 #ifdef arch_trigger_cpumask_backtrace
30 static void nmi_raise_cpu_backtrace(cpumask_t *mask)
32 apic->send_IPI_mask(mask, NMI_VECTOR);
35 void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
37 nmi_trigger_cpumask_backtrace(mask, exclude_self,
38 nmi_raise_cpu_backtrace);
41 static int nmi_cpu_backtrace_handler(unsigned int cmd, struct pt_regs *regs)
43 if (nmi_cpu_backtrace(regs))
48 NOKPROBE_SYMBOL(nmi_cpu_backtrace_handler);
50 static int __init register_nmi_cpu_backtrace_handler(void)
52 register_nmi_handler(NMI_LOCAL, nmi_cpu_backtrace_handler,
56 early_initcall(register_nmi_cpu_backtrace_handler);