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1#ifndef _LINUX_SCHED_LOADAVG_H
2#define _LINUX_SCHED_LOADAVG_H
3
4/*
5 * These are the constant used to fake the fixed-point load-average
6 * counting. Some notes:
7 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
8 * a load-average precision of 10 bits integer + 11 bits fractional
9 * - if you want to count load-averages more often, you need more
10 * precision, or rounding will get you. With 2-second counting freq,
11 * the EXP_n values would be 1981, 2034 and 2043 if still using only
12 * 11 bit fractions.
13 */
14extern unsigned long avenrun[]; /* Load averages */
15extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
16
17#define FSHIFT 11 /* nr of bits of precision */
18#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
19#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
20#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
21#define EXP_5 2014 /* 1/exp(5sec/5min) */
22#define EXP_15 2037 /* 1/exp(5sec/15min) */
23
24#define CALC_LOAD(load,exp,n) \
25 load *= exp; \
26 load += n*(FIXED_1-exp); \
27 load >>= FSHIFT;
28
29extern void calc_global_load(unsigned long ticks);
30
31#endif /* _LINUX_SCHED_LOADAVG_H */