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