#ifndef _LINUX_CONTEXT_TRACKING_STATE_H #define _LINUX_CONTEXT_TRACKING_STATE_H #include <linux/percpu.h> #include <linux/static_key.h> struct context_tracking { /* * When active is false, probes are unset in order * to minimize overhead: TIF flags are cleared * and calls to user_enter/exit are ignored. This * may be further optimized using static keys. */ bool active; enum ctx_state { IN_KERNEL = 0, IN_USER, } state; }; #ifdef CONFIG_CONTEXT_TRACKING extern struct static_key context_tracking_enabled; DECLARE_PER_CPU(struct context_tracking, context_tracking); static inline bool context_tracking_is_enabled(void) { return static_key_false(&context_tracking_enabled); } static inline bool context_tracking_cpu_is_enabled(void) { return __this_cpu_read(context_tracking.active); } static inline bool context_tracking_in_user(void) { return __this_cpu_read(context_tracking.state) == IN_USER; } #else static inline bool context_tracking_in_user(void) { return false; } static inline bool context_tracking_active(void) { return false; } #endif /* CONFIG_CONTEXT_TRACKING */ #endif