/* SPDX-License-Identifier: GPL-2.0 */ /* * linux/include/linux/nmi.h */ #ifndef LINUX_NMI_H #define LINUX_NMI_H #include #include /* Arch specific watchdogs might need to share extra watchdog-related APIs. */ #if defined(CONFIG_HARDLOCKUP_DETECTOR_ARCH) || defined(CONFIG_HARDLOCKUP_DETECTOR_SPARC64) #include #endif #ifdef CONFIG_LOCKUP_DETECTOR void lockup_detector_init(void); void lockup_detector_retry_init(void); void lockup_detector_soft_poweroff(void); void lockup_detector_cleanup(void); extern int 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_retry_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', 'watchdog_hardlockup_user_enabled' and * 'watchdog_softlockup_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 WATCHDOG_HARDLOCKUP_ENABLED_BIT 0 #define WATCHDOG_SOFTOCKUP_ENABLED_BIT 1 #define WATCHDOG_HARDLOCKUP_ENABLED (1 << WATCHDOG_HARDLOCKUP_ENABLED_BIT) #define WATCHDOG_SOFTOCKUP_ENABLED (1 << WATCHDOG_SOFTOCKUP_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 /* Sparc64 has special implemetantion that is always enabled. */ #if defined(CONFIG_HARDLOCKUP_DETECTOR) || defined(CONFIG_HARDLOCKUP_DETECTOR_SPARC64) void arch_touch_nmi_watchdog(void); #else static inline void arch_touch_nmi_watchdog(void) { } #endif #if defined(CONFIG_HARDLOCKUP_DETECTOR_COUNTS_HRTIMER) void watchdog_hardlockup_touch_cpu(unsigned int cpu); void watchdog_hardlockup_check(unsigned int cpu, struct pt_regs *regs); #endif #if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF) extern void hardlockup_detector_perf_stop(void); extern void hardlockup_detector_perf_restart(void); extern void hardlockup_detector_perf_cleanup(void); #else static inline void hardlockup_detector_perf_stop(void) { } static inline void hardlockup_detector_perf_restart(void) { } static inline void hardlockup_detector_perf_cleanup(void) { } #endif void watchdog_hardlockup_stop(void); void watchdog_hardlockup_start(void); int watchdog_hardlockup_probe(void); void watchdog_hardlockup_enable(unsigned int cpu); void watchdog_hardlockup_disable(unsigned int cpu); void lockup_detector_reconfigure(void); #ifdef CONFIG_HARDLOCKUP_DETECTOR_BUDDY void watchdog_buddy_check_hardlockup(int hrtimer_interrupts); #else static inline void watchdog_buddy_check_hardlockup(int hrtimer_interrupts) {} #endif /** * touch_nmi_watchdog - manually reset the hardlockup watchdog timeout. * * If we support detecting hardlockups, touch_nmi_watchdog() may be * used to pet the watchdog (reset the timeout) - for code which * intentionally disables interrupts for a long time. This call is stateless. * * Though this function has "nmi" in the name, the hardlockup watchdog might * not be backed by NMIs. This function will likely be renamed to * touch_hardlockup_watchdog() in the future. */ static inline void touch_nmi_watchdog(void) { /* * Pass on to the hardlockup detector selected via CONFIG_. Note that * the hardlockup detector may not be arch-specific nor using NMIs * and the arch_touch_nmi_watchdog() function will likely be renamed * in the future. */ 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, -1); return true; } static inline bool trigger_allbutcpu_cpu_backtrace(int exclude_cpu) { arch_trigger_cpumask_backtrace(cpu_online_mask, exclude_cpu); return true; } static inline bool trigger_cpumask_backtrace(struct cpumask *mask) { arch_trigger_cpumask_backtrace(mask, -1); return true; } static inline bool trigger_single_cpu_backtrace(int cpu) { arch_trigger_cpumask_backtrace(cpumask_of(cpu), -1); return true; } /* generic implementation */ void nmi_trigger_cpumask_backtrace(const cpumask_t *mask, int exclude_cpu, 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_allbutcpu_cpu_backtrace(int exclude_cpu) { 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); bool arch_perf_nmi_is_available(void); #endif #if defined(CONFIG_HARDLOCKUP_CHECK_TIMESTAMP) && \ defined(CONFIG_HARDLOCKUP_DETECTOR_PERF) void watchdog_update_hrtimer_threshold(u64 period); #else static inline void watchdog_update_hrtimer_threshold(u64 period) { } #endif #ifdef CONFIG_HAVE_ACPI_APEI_NMI #include #endif #ifdef CONFIG_NMI_CHECK_CPU void nmi_backtrace_stall_snap(const struct cpumask *btp); void nmi_backtrace_stall_check(const struct cpumask *btp); #else static inline void nmi_backtrace_stall_snap(const struct cpumask *btp) {} static inline void nmi_backtrace_stall_check(const struct cpumask *btp) {} #endif #endif