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