1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * HW NMI watchdog support
4 *
5 * started by Don Zickus, Copyright (C) 2010 Red Hat, Inc.
6 *
7 * Arch specific calls to support NMI watchdog
8 *
9 * Bits copied from original nmi.c file
10 *
11 */
12 #include <asm/apic.h>
13 #include <asm/nmi.h>
14
15 #include <linux/cpumask.h>
16 #include <linux/kdebug.h>
17 #include <linux/notifier.h>
18 #include <linux/kprobes.h>
19 #include <linux/nmi.h>
20 #include <linux/init.h>
21 #include <linux/delay.h>
22
23 #ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
hw_nmi_get_sample_period(int watchdog_thresh)24 u64 hw_nmi_get_sample_period(int watchdog_thresh)
25 {
26 return (u64)(cpu_khz) * 1000 * watchdog_thresh;
27 }
28 #endif
29
30 #ifdef arch_trigger_cpumask_backtrace
nmi_raise_cpu_backtrace(cpumask_t * mask)31 static void nmi_raise_cpu_backtrace(cpumask_t *mask)
32 {
33 apic->send_IPI_mask(mask, NMI_VECTOR);
34 }
35
arch_trigger_cpumask_backtrace(const cpumask_t * mask,bool exclude_self)36 void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
37 {
38 nmi_trigger_cpumask_backtrace(mask, exclude_self,
39 nmi_raise_cpu_backtrace);
40 }
41
nmi_cpu_backtrace_handler(unsigned int cmd,struct pt_regs * regs)42 static int nmi_cpu_backtrace_handler(unsigned int cmd, struct pt_regs *regs)
43 {
44 if (nmi_cpu_backtrace(regs))
45 return NMI_HANDLED;
46
47 return NMI_DONE;
48 }
49 NOKPROBE_SYMBOL(nmi_cpu_backtrace_handler);
50
register_nmi_cpu_backtrace_handler(void)51 static int __init register_nmi_cpu_backtrace_handler(void)
52 {
53 register_nmi_handler(NMI_LOCAL, nmi_cpu_backtrace_handler,
54 0, "arch_bt");
55 return 0;
56 }
57 early_initcall(register_nmi_cpu_backtrace_handler);
58 #endif
59
