[deliverable/linux.git] / include / linux / context_tracking_state.h

#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_in_user(void)
{
	return __this_cpu_read(context_tracking.state) == IN_USER;
}

static inline bool context_tracking_active(void)
{
	return __this_cpu_read(context_tracking.active);
}
#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
Commit	Line	Data
e7358b3b FW	1	#ifndef _LINUX_CONTEXT_TRACKING_STATE_H
	2	#define _LINUX_CONTEXT_TRACKING_STATE_H
	3
	4	#include <linux/percpu.h>
	5	#include <linux/static_key.h>
	6
	7	struct context_tracking {
	8	/*
	9	* When active is false, probes are unset in order
	10	* to minimize overhead: TIF flags are cleared
	11	* and calls to user_enter/exit are ignored. This
	12	* may be further optimized using static keys.
	13	*/
	14	bool active;
	15	enum ctx_state {
	16	IN_KERNEL = 0,
	17	IN_USER,
	18	} state;
	19	};
	20
	21	#ifdef CONFIG_CONTEXT_TRACKING
	22	extern struct static_key context_tracking_enabled;
	23	DECLARE_PER_CPU(struct context_tracking, context_tracking);
	24
	25	static inline bool context_tracking_in_user(void)
	26	{
	27	return __this_cpu_read(context_tracking.state) == IN_USER;
	28	}
	29
	30	static inline bool context_tracking_active(void)
	31	{
	32	return __this_cpu_read(context_tracking.active);
	33	}
	34	#else
	35	static inline bool context_tracking_in_user(void) { return false; }
	36	static inline bool context_tracking_active(void) { return false; }
	37	#endif /* CONFIG_CONTEXT_TRACKING */
	38
	39	#endif