root/include/linux/nmi.h

INCLUDED FROM

DEFINITIONS

1. lockup_detector_init
2. lockup_detector_soft_poweroff
3. lockup_detector_cleanup
4. touch_softlockup_watchdog_sched
5. touch_softlockup_watchdog
6. touch_softlockup_watchdog_sync
7. touch_all_softlockup_watchdogs
8. reset_hung_task_detector
9. hardlockup_detector_disable
10. hardlockup_detector_perf_stop
11. hardlockup_detector_perf_restart
12. hardlockup_detector_perf_disable
13. hardlockup_detector_perf_enable
14. hardlockup_detector_perf_cleanup
15. hardlockup_detector_perf_init
16. arch_touch_nmi_watchdog
17. hardlockup_detector_perf_init
18. touch_nmi_watchdog
19. trigger_all_cpu_backtrace
20. trigger_allbutself_cpu_backtrace
21. trigger_cpumask_backtrace
22. trigger_single_cpu_backtrace
23. trigger_all_cpu_backtrace
24. trigger_allbutself_cpu_backtrace
25. trigger_cpumask_backtrace
26. trigger_single_cpu_backtrace
27. watchdog_update_hrtimer_threshold

   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
  15 void lockup_detector_init(void);
  16 void lockup_detector_soft_poweroff(void);
  17 void lockup_detector_cleanup(void);
  18 bool is_hardlockup(void);
  19 
  20 extern int watchdog_user_enabled;
  21 extern int nmi_watchdog_user_enabled;
  22 extern int soft_watchdog_user_enabled;
  23 extern int watchdog_thresh;
  24 extern unsigned long watchdog_enabled;
  25 
  26 extern struct cpumask watchdog_cpumask;
  27 extern unsigned long *watchdog_cpumask_bits;
  28 #ifdef CONFIG_SMP
  29 extern int sysctl_softlockup_all_cpu_backtrace;
  30 extern 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 */
  37 static inline void lockup_detector_init(void) { }
  38 static inline void lockup_detector_soft_poweroff(void) { }
  39 static inline void lockup_detector_cleanup(void) { }
  40 #endif /* !CONFIG_LOCKUP_DETECTOR */
  41 
  42 #ifdef CONFIG_SOFTLOCKUP_DETECTOR
  43 extern void touch_softlockup_watchdog_sched(void);
  44 extern void touch_softlockup_watchdog(void);
  45 extern void touch_softlockup_watchdog_sync(void);
  46 extern void touch_all_softlockup_watchdogs(void);
  47 extern unsigned int  softlockup_panic;
  48 
  49 extern int lockup_detector_online_cpu(unsigned int cpu);
  50 extern int lockup_detector_offline_cpu(unsigned int cpu);
  51 #else /* CONFIG_SOFTLOCKUP_DETECTOR */
  52 static inline void touch_softlockup_watchdog_sched(void) { }
  53 static inline void touch_softlockup_watchdog(void) { }
  54 static inline void touch_softlockup_watchdog_sync(void) { }
  55 static 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
  62 void reset_hung_task_detector(void);
  63 #else
  64 static 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)
  85 extern void hardlockup_detector_disable(void);
  86 extern unsigned int hardlockup_panic;
  87 #else
  88 static 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)
  98 extern void arch_touch_nmi_watchdog(void);
  99 extern void hardlockup_detector_perf_stop(void);
 100 extern void hardlockup_detector_perf_restart(void);
 101 extern void hardlockup_detector_perf_disable(void);
 102 extern void hardlockup_detector_perf_enable(void);
 103 extern void hardlockup_detector_perf_cleanup(void);
 104 extern int hardlockup_detector_perf_init(void);
 105 #else
 106 static inline void hardlockup_detector_perf_stop(void) { }
 107 static inline void hardlockup_detector_perf_restart(void) { }
 108 static inline void hardlockup_detector_perf_disable(void) { }
 109 static inline void hardlockup_detector_perf_enable(void) { }
 110 static inline void hardlockup_detector_perf_cleanup(void) { }
 111 # if !defined(CONFIG_HAVE_NMI_WATCHDOG)
 112 static inline int hardlockup_detector_perf_init(void) { return -ENODEV; }
 113 static inline void arch_touch_nmi_watchdog(void) {}
 114 # else
 115 static inline int hardlockup_detector_perf_init(void) { return 0; }
 116 # endif
 117 #endif
 118 
 119 void watchdog_nmi_stop(void);
 120 void watchdog_nmi_start(void);
 121 int watchdog_nmi_probe(void);
 122 int watchdog_nmi_enable(unsigned int cpu);
 123 void 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  */
 132 static 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
 144 static inline bool trigger_all_cpu_backtrace(void)
 145 {
 146         arch_trigger_cpumask_backtrace(cpu_online_mask, false);
 147         return true;
 148 }
 149 
 150 static inline bool trigger_allbutself_cpu_backtrace(void)
 151 {
 152         arch_trigger_cpumask_backtrace(cpu_online_mask, true);
 153         return true;
 154 }
 155 
 156 static inline bool trigger_cpumask_backtrace(struct cpumask *mask)
 157 {
 158         arch_trigger_cpumask_backtrace(mask, false);
 159         return true;
 160 }
 161 
 162 static 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 */
 169 void nmi_trigger_cpumask_backtrace(const cpumask_t *mask,
 170                                    bool exclude_self,
 171                                    void (*raise)(cpumask_t *mask));
 172 bool nmi_cpu_backtrace(struct pt_regs *regs);
 173 
 174 #else
 175 static inline bool trigger_all_cpu_backtrace(void)
 176 {
 177         return false;
 178 }
 179 static inline bool trigger_allbutself_cpu_backtrace(void)
 180 {
 181         return false;
 182 }
 183 static inline bool trigger_cpumask_backtrace(struct cpumask *mask)
 184 {
 185         return false;
 186 }
 187 static inline bool trigger_single_cpu_backtrace(int cpu)
 188 {
 189         return false;
 190 }
 191 #endif
 192 
 193 #ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
 194 u64 hw_nmi_get_sample_period(int watchdog_thresh);
 195 #endif
 196 
 197 #if defined(CONFIG_HARDLOCKUP_CHECK_TIMESTAMP) && \
 198     defined(CONFIG_HARDLOCKUP_DETECTOR)
 199 void watchdog_update_hrtimer_threshold(u64 period);
 200 #else
 201 static inline void watchdog_update_hrtimer_threshold(u64 period) { }
 202 #endif
 203 
 204 struct ctl_table;
 205 extern int proc_watchdog(struct ctl_table *, int ,
 206                          void __user *, size_t *, loff_t *);
 207 extern int proc_nmi_watchdog(struct ctl_table *, int ,
 208                              void __user *, size_t *, loff_t *);
 209 extern int proc_soft_watchdog(struct ctl_table *, int ,
 210                               void __user *, size_t *, loff_t *);
 211 extern int proc_watchdog_thresh(struct ctl_table *, int ,
 212                                 void __user *, size_t *, loff_t *);
 213 extern int proc_watchdog_cpumask(struct ctl_table *, int,
 214                                  void __user *, size_t *, loff_t *);
 215 
 216 #ifdef CONFIG_HAVE_ACPI_APEI_NMI
 217 #include <asm/nmi.h>
 218 #endif
 219 
 220 #endif