wmcpuload/src/cpu_bsdi.c

   1 /*
   2  * cpu_bsdi - module to get cpu usage, for BSDi
   3  *
   4  * Copyright (C) 2001, 2002 Seiichi SATO <ssato@sh.rim.or.jp>
   5  * Copyright (C)       2002 Nicolas Belan <belan@matranet.com>
   6  *
   7  * Licensed under the GPL
   8  */
   9
  10 #ifdef HAVE_CONFIG_H
  11 #include "config.h"
  12 #endif
  13
  14 #include <stdio.h>
  15 #include <unistd.h>
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include "cpu.h"
  19
  20 #include <sys/param.h>
  21 #include <sys/sysctl.h>
  22 #include <sys/dkstat.h>
  23
  24 void
  25 cpu_init(void)
  26 {
  27     /* You don't need initialization under BSDi */
  28     return;
  29 }
  30
  31 /* Returns the current CPU usage in percent */
  32 int
  33 cpu_get_usage(struct cpu_options *opts)
  34 {
  35     int total, used, result;
  36     static int pre_total, pre_used;
  37         struct cpustats cpustat;
  38         int mib[] = { CTL_KERN, KERN_CPUSTATS };
  39     size_t size = sizeof(struct cpustats);
  40
  41     /* get cpu time*/
  42     if (sysctl(mib, 2, &cpustat, &size, NULL, 0) < 0)
  43         return 0;
  44
  45     /* calc usage */
  46     used = cpustat.cp_time[CP_USER] + cpustat.cp_time[CP_SYS];
  47     if (!opts->ignore_nice)
  48         used += cpustat.cp_time[CP_NICE];
  49     total = used + cpustat.cp_time[CP_IDLE];
  50
  51     if (pre_total == 0)
  52         result = 0;
  53     else if ((total - pre_total) > 0)
  54         result = 100 * (double)(used - pre_used) / (double)(total - pre_total);
  55     else
  56         result = 0;
  57
  58     /* save used/total for next calculation */
  59     pre_used = used;
  60     pre_total = total;
  61
  62     return result;
  63 }