linux/include/linux/sched/loadavg.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_SCHED_LOADAVG_H
#define _LINUX_SCHED_LOADAVG_H

/*
 * These are the constant used to fake the fixed-point load-average
 * counting. Some notes:
 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
 *    a load-average precision of 10 bits integer + 11 bits fractional
 *  - if you want to count load-averages more often, you need more
 *    precision, or rounding will get you. With 2-second counting freq,
 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 *    11 bit fractions.
 */
extern unsigned long avenrun[];		/* Load averages */
extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);

#define FSHIFT …
#define FIXED_1 …
#define LOAD_FREQ …
#define EXP_1 …
#define EXP_5 …
#define EXP_15 …

/*
 * a1 = a0 * e + a * (1 - e)
 */
static inline unsigned long
calc_load(unsigned long load, unsigned long exp, unsigned long active)
{ … }

extern unsigned long calc_load_n(unsigned long load, unsigned long exp,
				 unsigned long active, unsigned int n);

#define LOAD_INT(x) …
#define LOAD_FRAC(x) …

extern void calc_global_load(void);

#endif /* _LINUX_SCHED_LOADAVG_H */