nmi.h (6880B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * linux/include/linux/nmi.h 4 */ 5#ifndef LINUX_NMI_H 6#define LINUX_NMI_H 7 8#include <linux/sched.h> 9#include <asm/irq.h> 10#if defined(CONFIG_HAVE_NMI_WATCHDOG) 11#include <asm/nmi.h> 12#endif 13 14#ifdef CONFIG_LOCKUP_DETECTOR 15void lockup_detector_init(void); 16void lockup_detector_soft_poweroff(void); 17void lockup_detector_cleanup(void); 18bool is_hardlockup(void); 19 20extern int watchdog_user_enabled; 21extern int nmi_watchdog_user_enabled; 22extern int soft_watchdog_user_enabled; 23extern int watchdog_thresh; 24extern unsigned long watchdog_enabled; 25 26extern struct cpumask watchdog_cpumask; 27extern unsigned long *watchdog_cpumask_bits; 28#ifdef CONFIG_SMP 29extern int sysctl_softlockup_all_cpu_backtrace; 30extern int sysctl_hardlockup_all_cpu_backtrace; 31#else 32#define sysctl_softlockup_all_cpu_backtrace 0 33#define sysctl_hardlockup_all_cpu_backtrace 0 34#endif /* !CONFIG_SMP */ 35 36#else /* CONFIG_LOCKUP_DETECTOR */ 37static inline void lockup_detector_init(void) { } 38static inline void lockup_detector_soft_poweroff(void) { } 39static inline void lockup_detector_cleanup(void) { } 40#endif /* !CONFIG_LOCKUP_DETECTOR */ 41 42#ifdef CONFIG_SOFTLOCKUP_DETECTOR 43extern void touch_softlockup_watchdog_sched(void); 44extern void touch_softlockup_watchdog(void); 45extern void touch_softlockup_watchdog_sync(void); 46extern void touch_all_softlockup_watchdogs(void); 47extern unsigned int softlockup_panic; 48 49extern int lockup_detector_online_cpu(unsigned int cpu); 50extern int lockup_detector_offline_cpu(unsigned int cpu); 51#else /* CONFIG_SOFTLOCKUP_DETECTOR */ 52static inline void touch_softlockup_watchdog_sched(void) { } 53static inline void touch_softlockup_watchdog(void) { } 54static inline void touch_softlockup_watchdog_sync(void) { } 55static inline void touch_all_softlockup_watchdogs(void) { } 56 57#define lockup_detector_online_cpu NULL 58#define lockup_detector_offline_cpu NULL 59#endif /* CONFIG_SOFTLOCKUP_DETECTOR */ 60 61#ifdef CONFIG_DETECT_HUNG_TASK 62void reset_hung_task_detector(void); 63#else 64static inline void reset_hung_task_detector(void) { } 65#endif 66 67/* 68 * The run state of the lockup detectors is controlled by the content of the 69 * 'watchdog_enabled' variable. Each lockup detector has its dedicated bit - 70 * bit 0 for the hard lockup detector and bit 1 for the soft lockup detector. 71 * 72 * 'watchdog_user_enabled', 'nmi_watchdog_user_enabled' and 73 * 'soft_watchdog_user_enabled' are variables that are only used as an 74 * 'interface' between the parameters in /proc/sys/kernel and the internal 75 * state bits in 'watchdog_enabled'. The 'watchdog_thresh' variable is 76 * handled differently because its value is not boolean, and the lockup 77 * detectors are 'suspended' while 'watchdog_thresh' is equal zero. 78 */ 79#define NMI_WATCHDOG_ENABLED_BIT 0 80#define SOFT_WATCHDOG_ENABLED_BIT 1 81#define NMI_WATCHDOG_ENABLED (1 << NMI_WATCHDOG_ENABLED_BIT) 82#define SOFT_WATCHDOG_ENABLED (1 << SOFT_WATCHDOG_ENABLED_BIT) 83 84#if defined(CONFIG_HARDLOCKUP_DETECTOR) 85extern void hardlockup_detector_disable(void); 86extern unsigned int hardlockup_panic; 87#else 88static inline void hardlockup_detector_disable(void) {} 89#endif 90 91#if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR) 92# define NMI_WATCHDOG_SYSCTL_PERM 0644 93#else 94# define NMI_WATCHDOG_SYSCTL_PERM 0444 95#endif 96 97#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF) 98extern void arch_touch_nmi_watchdog(void); 99extern void hardlockup_detector_perf_stop(void); 100extern void hardlockup_detector_perf_restart(void); 101extern void hardlockup_detector_perf_disable(void); 102extern void hardlockup_detector_perf_enable(void); 103extern void hardlockup_detector_perf_cleanup(void); 104extern int hardlockup_detector_perf_init(void); 105#else 106static inline void hardlockup_detector_perf_stop(void) { } 107static inline void hardlockup_detector_perf_restart(void) { } 108static inline void hardlockup_detector_perf_disable(void) { } 109static inline void hardlockup_detector_perf_enable(void) { } 110static inline void hardlockup_detector_perf_cleanup(void) { } 111# if !defined(CONFIG_HAVE_NMI_WATCHDOG) 112static inline int hardlockup_detector_perf_init(void) { return -ENODEV; } 113static inline void arch_touch_nmi_watchdog(void) {} 114# else 115static inline int hardlockup_detector_perf_init(void) { return 0; } 116# endif 117#endif 118 119void watchdog_nmi_stop(void); 120void watchdog_nmi_start(void); 121int watchdog_nmi_probe(void); 122int watchdog_nmi_enable(unsigned int cpu); 123void watchdog_nmi_disable(unsigned int cpu); 124 125/** 126 * touch_nmi_watchdog - restart NMI watchdog timeout. 127 * 128 * If the architecture supports the NMI watchdog, touch_nmi_watchdog() 129 * may be used to reset the timeout - for code which intentionally 130 * disables interrupts for a long time. This call is stateless. 131 */ 132static inline void touch_nmi_watchdog(void) 133{ 134 arch_touch_nmi_watchdog(); 135 touch_softlockup_watchdog(); 136} 137 138/* 139 * Create trigger_all_cpu_backtrace() out of the arch-provided 140 * base function. Return whether such support was available, 141 * to allow calling code to fall back to some other mechanism: 142 */ 143#ifdef arch_trigger_cpumask_backtrace 144static inline bool trigger_all_cpu_backtrace(void) 145{ 146 arch_trigger_cpumask_backtrace(cpu_online_mask, false); 147 return true; 148} 149 150static inline bool trigger_allbutself_cpu_backtrace(void) 151{ 152 arch_trigger_cpumask_backtrace(cpu_online_mask, true); 153 return true; 154} 155 156static inline bool trigger_cpumask_backtrace(struct cpumask *mask) 157{ 158 arch_trigger_cpumask_backtrace(mask, false); 159 return true; 160} 161 162static inline bool trigger_single_cpu_backtrace(int cpu) 163{ 164 arch_trigger_cpumask_backtrace(cpumask_of(cpu), false); 165 return true; 166} 167 168/* generic implementation */ 169void nmi_trigger_cpumask_backtrace(const cpumask_t *mask, 170 bool exclude_self, 171 void (*raise)(cpumask_t *mask)); 172bool nmi_cpu_backtrace(struct pt_regs *regs); 173 174#else 175static inline bool trigger_all_cpu_backtrace(void) 176{ 177 return false; 178} 179static inline bool trigger_allbutself_cpu_backtrace(void) 180{ 181 return false; 182} 183static inline bool trigger_cpumask_backtrace(struct cpumask *mask) 184{ 185 return false; 186} 187static inline bool trigger_single_cpu_backtrace(int cpu) 188{ 189 return false; 190} 191#endif 192 193#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF 194u64 hw_nmi_get_sample_period(int watchdog_thresh); 195#endif 196 197#if defined(CONFIG_HARDLOCKUP_CHECK_TIMESTAMP) && \ 198 defined(CONFIG_HARDLOCKUP_DETECTOR) 199void watchdog_update_hrtimer_threshold(u64 period); 200#else 201static inline void watchdog_update_hrtimer_threshold(u64 period) { } 202#endif 203 204struct ctl_table; 205int proc_watchdog(struct ctl_table *, int, void *, size_t *, loff_t *); 206int proc_nmi_watchdog(struct ctl_table *, int , void *, size_t *, loff_t *); 207int proc_soft_watchdog(struct ctl_table *, int , void *, size_t *, loff_t *); 208int proc_watchdog_thresh(struct ctl_table *, int , void *, size_t *, loff_t *); 209int proc_watchdog_cpumask(struct ctl_table *, int, void *, size_t *, loff_t *); 210 211#ifdef CONFIG_HAVE_ACPI_APEI_NMI 212#include <asm/nmi.h> 213#endif 214 215#endif