| // 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 <linux/thread_info.h> |
| #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 |