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