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

 
  1/*
  2 *  linux/include/linux/nmi.h
  3 */
  4#ifndef LINUX_NMI_H
  5#define LINUX_NMI_H
  6
  7#include <linux/sched.h>
  8#include <asm/irq.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  9
 10/**
 11 * touch_nmi_watchdog - restart NMI watchdog timeout.
 12 * 
 13 * If the architecture supports the NMI watchdog, touch_nmi_watchdog()
 14 * may be used to reset the timeout - for code which intentionally
 15 * disables interrupts for a long time. This call is stateless.
 16 */
 17#if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)
 18#include <asm/nmi.h>
 19extern void touch_nmi_watchdog(void);
 20#else
 21static inline void touch_nmi_watchdog(void)
 22{
 
 23	touch_softlockup_watchdog();
 24}
 25#endif
 26
 27#if defined(CONFIG_HARDLOCKUP_DETECTOR)
 28extern void hardlockup_detector_disable(void);
 29#else
 30static inline void hardlockup_detector_disable(void) {}
 31#endif
 32
 33/*
 34 * Create trigger_all_cpu_backtrace() out of the arch-provided
 35 * base function. Return whether such support was available,
 36 * to allow calling code to fall back to some other mechanism:
 37 */
 38#ifdef arch_trigger_all_cpu_backtrace
 39static inline bool trigger_all_cpu_backtrace(void)
 40{
 41	arch_trigger_all_cpu_backtrace(true);
 
 
 42
 
 
 
 43	return true;
 44}
 45static inline bool trigger_allbutself_cpu_backtrace(void)
 
 
 
 
 
 
 
 46{
 47	arch_trigger_all_cpu_backtrace(false);
 48	return true;
 49}
 50
 51/* generic implementation */
 52void nmi_trigger_all_cpu_backtrace(bool include_self,
 
 53				   void (*raise)(cpumask_t *mask));
 54bool nmi_cpu_backtrace(struct pt_regs *regs);
 55
 56#else
 57static inline bool trigger_all_cpu_backtrace(void)
 58{
 59	return false;
 60}
 61static inline bool trigger_allbutself_cpu_backtrace(void)
 62{
 63	return false;
 64}
 
 
 
 
 
 
 
 
 65#endif
 66
 67#ifdef CONFIG_LOCKUP_DETECTOR
 68u64 hw_nmi_get_sample_period(int watchdog_thresh);
 69extern int nmi_watchdog_enabled;
 70extern int soft_watchdog_enabled;
 71extern int watchdog_user_enabled;
 72extern int watchdog_thresh;
 73extern unsigned long *watchdog_cpumask_bits;
 74extern int sysctl_softlockup_all_cpu_backtrace;
 75extern int sysctl_hardlockup_all_cpu_backtrace;
 76struct ctl_table;
 77extern int proc_watchdog(struct ctl_table *, int ,
 78			 void __user *, size_t *, loff_t *);
 79extern int proc_nmi_watchdog(struct ctl_table *, int ,
 80			     void __user *, size_t *, loff_t *);
 81extern int proc_soft_watchdog(struct ctl_table *, int ,
 82			      void __user *, size_t *, loff_t *);
 83extern int proc_watchdog_thresh(struct ctl_table *, int ,
 84				void __user *, size_t *, loff_t *);
 85extern int proc_watchdog_cpumask(struct ctl_table *, int,
 86				 void __user *, size_t *, loff_t *);
 87extern int lockup_detector_suspend(void);
 88extern void lockup_detector_resume(void);
 89#else
 90static inline int lockup_detector_suspend(void)
 91{
 92	return 0;
 93}
 94
 95static inline void lockup_detector_resume(void)
 96{
 97}
 98#endif
 
 
 99
100#ifdef CONFIG_HAVE_ACPI_APEI_NMI
101#include <asm/nmi.h>
102#endif
103
104#endif