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1 : : /* SPDX-License-Identifier: GPL-2.0 */ 2 : : #ifndef _LINUX_SCHED_LOADAVG_H 3 : : #define _LINUX_SCHED_LOADAVG_H 4 : : 5 : : /* 6 : : * These are the constant used to fake the fixed-point load-average 7 : : * counting. Some notes: 8 : : * - 11 bit fractions expand to 22 bits by the multiplies: this gives 9 : : * a load-average precision of 10 bits integer + 11 bits fractional 10 : : * - if you want to count load-averages more often, you need more 11 : : * precision, or rounding will get you. With 2-second counting freq, 12 : : * the EXP_n values would be 1981, 2034 and 2043 if still using only 13 : : * 11 bit fractions. 14 : : */ 15 : : extern unsigned long avenrun[]; /* Load averages */ 16 : : extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 17 : : 18 : : #define FSHIFT 11 /* nr of bits of precision */ 19 : : #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 20 : : #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 21 : : #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 22 : : #define EXP_5 2014 /* 1/exp(5sec/5min) */ 23 : : #define EXP_15 2037 /* 1/exp(5sec/15min) */ 24 : : 25 : : /* 26 : : * a1 = a0 * e + a * (1 - e) 27 : : */ 28 : : static inline unsigned long 29 : : calc_load(unsigned long load, unsigned long exp, unsigned long active) 30 : : { 31 : : unsigned long newload; 32 : : 33 : 3 : newload = load * exp + active * (FIXED_1 - exp); 34 : 3 : if (active >= load) 35 : 3 : newload += FIXED_1-1; 36 : : 37 : 3 : return newload / FIXED_1; 38 : : } 39 : : 40 : : extern unsigned long calc_load_n(unsigned long load, unsigned long exp, 41 : : unsigned long active, unsigned int n); 42 : : 43 : : #define LOAD_INT(x) ((x) >> FSHIFT) 44 : : #define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) 45 : : 46 : : extern void calc_global_load(unsigned long ticks); 47 : : 48 : : #endif /* _LINUX_SCHED_LOADAVG_H */