hw_nmi.c 1.32 KB
Newer Older
1
// SPDX-License-Identifier: GPL-2.0
2 3 4 5 6 7 8 9 10 11
/*
 *  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
 *
 */
12
#include <linux/thread_info.h>
13
#include <asm/apic.h>
14
#include <asm/nmi.h>
15 16

#include <linux/cpumask.h>
17 18 19
#include <linux/kdebug.h>
#include <linux/notifier.h>
#include <linux/kprobes.h>
20
#include <linux/nmi.h>
21
#include <linux/init.h>
22
#include <linux/delay.h>
23

24
#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
25
u64 hw_nmi_get_sample_period(int watchdog_thresh)
26
{
27
	return (u64)(cpu_khz) * 1000 * watchdog_thresh;
28
}
29
#endif
30

31
#ifdef arch_trigger_cpumask_backtrace
32
static void nmi_raise_cpu_backtrace(cpumask_t *mask)
33
{
34
	apic->send_IPI_mask(mask, NMI_VECTOR);
35 36
}

37
void arch_trigger_cpumask_backtrace(const cpumask_t *mask, int exclude_cpu)
38
{
39
	nmi_trigger_cpumask_backtrace(mask, exclude_cpu,
40
				      nmi_raise_cpu_backtrace);
41 42
}

43
static int nmi_cpu_backtrace_handler(unsigned int cmd, struct pt_regs *regs)
44
{
45
	if (nmi_cpu_backtrace(regs))
46
		return NMI_HANDLED;
47

48
	return NMI_DONE;
49
}
50
NOKPROBE_SYMBOL(nmi_cpu_backtrace_handler);
51

52
static int __init register_nmi_cpu_backtrace_handler(void)
53
{
54
	register_nmi_handler(NMI_LOCAL, nmi_cpu_backtrace_handler,
55
				0, "arch_bt");
56 57
	return 0;
}
58
early_initcall(register_nmi_cpu_backtrace_handler);
59
#endif