66 lines
1.9 KiB
C
66 lines
1.9 KiB
C
/* ProcFS - util.c - by Alen Stojanov and David van Moolenbroek */
|
|
|
|
#include "inc.h"
|
|
|
|
/*===========================================================================*
|
|
* procfs_getloadavg *
|
|
*===========================================================================*/
|
|
int procfs_getloadavg(struct load *loadavg, int nelem)
|
|
{
|
|
/* Retrieve system load average information.
|
|
*/
|
|
struct loadinfo loadinfo;
|
|
u32_t system_hz, ticks_per_slot;
|
|
int p, unfilled_ticks;
|
|
int minutes[3] = { 1, 5, 15 };
|
|
ssize_t l;
|
|
|
|
if(nelem < 1) {
|
|
errno = ENOSPC;
|
|
return -1;
|
|
}
|
|
|
|
system_hz = sys_hz();
|
|
|
|
if((l=sys_getloadinfo(&loadinfo)) != OK)
|
|
return -1;
|
|
if(nelem > 3)
|
|
nelem = 3;
|
|
|
|
/* How many ticks are missing from the newest-filled slot? */
|
|
ticks_per_slot = _LOAD_UNIT_SECS * system_hz;
|
|
unfilled_ticks =
|
|
ticks_per_slot - (loadinfo.last_clock % ticks_per_slot);
|
|
|
|
for(p = 0; p < nelem; p++) {
|
|
int h, slots;
|
|
int latest = loadinfo.proc_last_slot;
|
|
slots = minutes[p] * 60 / _LOAD_UNIT_SECS;
|
|
loadavg[p].proc_load = 0;
|
|
|
|
/* Add up the total number of process ticks for this number
|
|
* of minutes (minutes[p]). Start with the newest slot, which
|
|
* is latest, and count back for the number of slots that
|
|
* correspond to the right number of minutes. Take wraparound
|
|
* into account by calculating the index modulo _LOAD_HISTORY,
|
|
* which is the number of slots of history kept.
|
|
*/
|
|
for(h = 0; h < slots; h++) {
|
|
int slot;
|
|
slot = (latest - h + _LOAD_HISTORY) % _LOAD_HISTORY;
|
|
loadavg[p].proc_load +=
|
|
loadinfo.proc_load_history[slot];
|
|
l += (double) loadinfo.proc_load_history[slot];
|
|
}
|
|
|
|
/* The load average over this number of minutes is the number
|
|
* of process-ticks divided by the number of ticks, not
|
|
* counting the number of ticks the last slot hasn't been
|
|
* around yet.
|
|
*/
|
|
loadavg[p].ticks = slots * ticks_per_slot - unfilled_ticks;
|
|
}
|
|
|
|
return nelem;
|
|
}
|