diff options
Diffstat (limited to 'include/linux/sched/loadavg.h')
| -rw-r--r-- | include/linux/sched/loadavg.h | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/include/linux/sched/loadavg.h b/include/linux/sched/loadavg.h new file mode 100644 index 000000000000..4264bc6b2c27 --- /dev/null +++ b/include/linux/sched/loadavg.h @@ -0,0 +1,31 @@ +#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 11 /* nr of bits of precision */ +#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ +#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ +#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ +#define EXP_5 2014 /* 1/exp(5sec/5min) */ +#define EXP_15 2037 /* 1/exp(5sec/15min) */ + +#define CALC_LOAD(load,exp,n) \ + load *= exp; \ + load += n*(FIXED_1-exp); \ + load >>= FSHIFT; + +extern void calc_global_load(unsigned long ticks); + +#endif /* _LINUX_SCHED_LOADAVG_H */ |