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#ifndef _ASM_X86_TIMER_H
#define _ASM_X86_TIMER_H
#include <linux/percpu.h>
#include <linux/math64.h>
unsigned long long native_sched_clock(void);
extern int recalibrate_cpu_khz(void);
extern int no_timer_check;
/*
* We use the full linear equation: f(x) = a + b*x, in order to allow
* a continuous function in the face of dynamic freq changes.
*
* Continuity means that when our frequency changes our slope (b); we want to
* ensure that: f(t) == f'(t), which gives: a + b*t == a' + b'*t.
*
* Without an offset (a) the above would not be possible.
*
* See the comment near cycles_2_ns() for details on how we compute (b).
*/
struct cyc2ns_data {
u32 cyc2ns_mul;
u32 cyc2ns_shift;
u64 cyc2ns_offset;
u32 __count;
/* u32 hole */
}; /* 24 bytes -- do not grow */
extern struct cyc2ns_data *cyc2ns_read_begin(void);
extern void cyc2ns_read_end(struct cyc2ns_data *);