/* SPDX-License-Identifier: GPL-2.0 */ /* * linux/include/linux/nmi.h */ #ifndef LINUX_NMI_H #define LINUX_NMI_H #include <linux/sched.h> #include <asm/irq.h> #if defined(CONFIG_HAVE_NMI_WATCHDOG) #include <asm/nmi.h> #endif #ifdef CONFIG_LOCKUP_DETECTOR void lockup_detector_init(void); void lockup_detector_soft_poweroff(void); void lockup_detector_cleanup(void); bool is_hardlockup(void); extern int watchdog_user_enabled; extern int nmi_watchdog_user_enabled; extern int soft_watchdog_user_enabled; extern int watchdog_thresh; extern unsigned long watchdog_enabled; extern struct cpumask watchdog_cpumask; extern unsigned long *watchdog_cpumask_bits; #ifdef CONFIG_SMP extern int sysctl_softlockup_all_cpu_backtrace; extern int sysctl_hardlockup_all_cpu_backtrace; #else #define sysctl_softlockup_all_cpu_backtrace 0 #define sysctl_hardlockup_all_cpu_backtrace 0 #endif /* !CONFIG_SMP */ #else /* CONFIG_LOCKUP_DETECTOR */ static inline void lockup_detector_init(void) { } static inline void lockup_detector_soft_poweroff(void) { } static inline void lockup_detector_cleanup(void) { } #endif /* !CONFIG_LOCKUP_DETECTOR */ #ifdef CONFIG_SOFTLOCKUP_DETECTOR extern void touch_softlockup_watchdog_sched(void); extern void touch_softlockup_watchdog(void); extern void touch_softlockup_watchdog_sync(void); extern void touch_all_softlockup_watchdogs(void); extern unsigned int softlockup_panic; extern int lockup_detector_online_cpu(unsigned int cpu); extern int lockup_detector_offline_cpu(unsigned int cpu); #else /* CONFIG_SOFTLOCKUP_DETECTOR */ static inline void touch_softlockup_watchdog_sched(void) { } static inline void touch_softlockup_watchdog(void) { } static inline void touch_softlockup_watchdog_sync(void) { } static inline void touch_all_softlockup_watchdogs(void) { } #define lockup_detector_online_cpu NULL #define lockup_detector_offline_cpu NULL #endif /* CONFIG_SOFTLOCKUP_DETECTOR */ #ifdef CONFIG_DETECT_HUNG_TASK void reset_hung_task_detector(void); #else static inline void reset_hung_task_detector(void) { } #endif /* * The run state of the lockup detectors is controlled by the content of the * 'watchdog_enabled' variable. Each lockup detector has its dedicated bit - * bit 0 for the hard lockup detector and bit 1 for the soft lockup detector. * * 'watchdog_user_enabled', 'nmi_watchdog_user_enabled' and * 'soft_watchdog_user_enabled' are variables that are only used as an * 'interface' between the parameters in /proc/sys/kernel and the internal * state bits in 'watchdog_enabled'. The 'watchdog_thresh' variable is * handled differently because its value is not boolean, and the lockup * detectors are 'suspended' while 'watchdog_thresh' is equal zero. */ #define NMI_WATCHDOG_ENABLED_BIT 0 #define SOFT_WATCHDOG_ENABLED_BIT 1 #define NMI_WATCHDOG_ENABLED (1 << NMI_WATCHDOG_ENABLED_BIT) #define SOFT_WATCHDOG_ENABLED (1 << SOFT_WATCHDOG_ENABLED_BIT) #if defined(CONFIG_HARDLOCKUP_DETECTOR) extern void hardlockup_detector_disable(void); extern unsigned int hardlockup_panic; #else static inline void hardlockup_detector_disable(void) {} #endif #if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR) # define NMI_WATCHDOG_SYSCTL_PERM 0644 #else # define NMI_WATCHDOG_SYSCTL_PERM 0444 #endif #if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF) extern void arch_touch_nmi_watchdog(void); extern void hardlockup_detector_perf_stop(void); extern void hardlockup_detector_perf_restart(void); extern void hardlockup_detector_perf_disable(void); extern void hardlockup_detector_perf_enable(void); extern void hardlockup_detector_perf_cleanup(void); extern int hardlockup_detector_perf_init(void); #else static inline void hardlockup_detector_perf_stop(void) { } static inline void hardlockup_detector_perf_restart(void) { } static inline void hardlockup_detector_perf_disable(void) { } static inline void hardlockup_detector_perf_enable(void) { } static inline void hardlockup_detector_perf_cleanup(void) { } # if !defined(CONFIG_HAVE_NMI_WATCHDOG) static inline int hardlockup_detector_perf_init(void) { return -ENODEV; } static inline void arch_touch_nmi_watchdog(void) {} # else static inline int hardlockup_detector_perf_init(void) { return 0; } # endif #endif void watchdog_nmi_stop(void); void watchdog_nmi_start(void); int watchdog_nmi_probe(void); int watchdog_nmi_enable(unsigned int cpu); void watchdog_nmi_disable(unsigned int cpu); /** * touch_nmi_watchdog - restart NMI watchdog timeout. * * If the architecture supports the NMI watchdog, touch_nmi_watchdog() * may be used to reset the timeout - for code which intentionally * disables interrupts for a long time. This call is stateless. */ static inline void touch_nmi_watchdog(void) { arch_touch_nmi_watchdog(); touch_softlockup_watchdog(); } /* * Create trigger_all_cpu_backtrace() out of the arch-provided * base function. Return whether such support was available, * to allow calling code to fall back to some other mechanism: */ #ifdef arch_trigger_cpumask_backtrace static inline bool trigger_all_cpu_backtrace(void) { arch_trigger_cpumask_backtrace(cpu_online_mask, false); return true; } static inline bool trigger_allbutself_cpu_backtrace(void) { arch_trigger_cpumask_backtrace(cpu_online_mask, true); return true; } static inline bool trigger_cpumask_backtrace(struct cpumask *mask) { arch_trigger_cpumask_backtrace(mask, false); return true; } static inline bool trigger_single_cpu_backtrace(int cpu) { arch_trigger_cpumask_backtrace(cpumask_of(cpu), false); return true; } /* generic implementation */ void nmi_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self, void (*raise)(cpumask_t *mask)); bool nmi_cpu_backtrace(struct pt_regs *regs); #else static inline bool trigger_all_cpu_backtrace(void) { return false; } static inline bool trigger_allbutself_cpu_backtrace(void) { return false; } static inline bool trigger_cpumask_backtrace(struct cpumask *mask) { return false; } static inline bool trigger_single_cpu_backtrace(int cpu) { return false; } #endif #ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF u64 hw_nmi_get_sample_period(int watchdog_thresh); #endif #if defined(CONFIG_HARDLOCKUP_CHECK_TIMESTAMP) && \ defined(CONFIG_HARDLOCKUP_DETECTOR) void watchdog_update_hrtimer_threshold(u64 period); #else static inline void watchdog_update_hrtimer_threshold(u64 period) { } #endif struct ctl_table; extern int proc_watchdog(struct ctl_table *, int , void __user *, size_t *, loff_t *); extern int proc_nmi_watchdog(struct ctl_table *, int , void __user *, size_t *, loff_t *); extern int proc_soft_watchdog(struct ctl_table *, int , void __user *, size_t *, loff_t *); extern int proc_watchdog_thresh(struct ctl_table *, int , void __user *, size_t *, loff_t *); extern int proc_watchdog_cpumask(struct ctl_table *, int, void __user *, size_t *, loff_t *); #ifdef CONFIG_HAVE_ACPI_APEI_NMI #include <asm/nmi.h> #endif #endif