1e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker#ifndef _LINUX_CONTEXT_TRACKING_STATE_H 2e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker#define _LINUX_CONTEXT_TRACKING_STATE_H 3e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker 4e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker#include <linux/percpu.h> 5e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker#include <linux/static_key.h> 6e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker 7e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbeckerstruct context_tracking { 8e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker /* 9e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker * When active is false, probes are unset in order 10e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker * to minimize overhead: TIF flags are cleared 11e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker * and calls to user_enter/exit are ignored. This 12e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker * may be further optimized using static keys. 13e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker */ 14e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker bool active; 15e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker enum ctx_state { 16e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker IN_KERNEL = 0, 17e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker IN_USER, 18e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker } state; 19e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker}; 20e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker 21e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker#ifdef CONFIG_CONTEXT_TRACKING 22e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbeckerextern struct static_key context_tracking_enabled; 23e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic WeisbeckerDECLARE_PER_CPU(struct context_tracking, context_tracking); 24e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker 2558135f574f1b791c926622387780ed3d090116d6Frederic Weisbeckerstatic inline bool context_tracking_is_enabled(void) 2658135f574f1b791c926622387780ed3d090116d6Frederic Weisbecker{ 2758135f574f1b791c926622387780ed3d090116d6Frederic Weisbecker return static_key_false(&context_tracking_enabled); 2858135f574f1b791c926622387780ed3d090116d6Frederic Weisbecker} 29d0df09ebfc126b23c1005f98ddecc9907f9c5d25Frederic Weisbecker 30d0df09ebfc126b23c1005f98ddecc9907f9c5d25Frederic Weisbeckerstatic inline bool context_tracking_cpu_is_enabled(void) 31e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker{ 32d0df09ebfc126b23c1005f98ddecc9907f9c5d25Frederic Weisbecker return __this_cpu_read(context_tracking.active); 33e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker} 34e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker 35d0df09ebfc126b23c1005f98ddecc9907f9c5d25Frederic Weisbeckerstatic inline bool context_tracking_in_user(void) 36e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker{ 37d0df09ebfc126b23c1005f98ddecc9907f9c5d25Frederic Weisbecker return __this_cpu_read(context_tracking.state) == IN_USER; 38e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker} 39e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker#else 40e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbeckerstatic inline bool context_tracking_in_user(void) { return false; } 41e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbeckerstatic inline bool context_tracking_active(void) { return false; } 42e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker#endif /* CONFIG_CONTEXT_TRACKING */ 43e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker 44e7358b3bc0d7fcec0e7a724477f06db2b0c68e21Frederic Weisbecker#endif 45