Node_Exporter/collector/cpu_freebsd.go
2015-07-14 13:58:54 +04:30

73 lines
1.9 KiB
Go

// +build !nocpu
package collector
import (
"errors"
"os"
"strconv"
"unsafe"
"github.com/prometheus/client_golang/prometheus"
)
/*
#cgo LDFLAGS: -lkvm
#include <fcntl.h>
#include <kvm.h>
#include <sys/param.h>
#include <sys/pcpu.h>
#include <sys/resource.h>
*/
import "C"
type statCollector struct {
cpu *prometheus.CounterVec
}
func init() {
Factories["cpu"] = NewStatCollector
}
// Takes a prometheus registry and returns a new Collector exposing
// CPU stats.
func NewStatCollector() (Collector, error) {
return &statCollector{
cpu: prometheus.NewCounterVec(
prometheus.CounterOpts{
Namespace: Namespace,
Name: "cpu_seconds_total",
Help: "Seconds the CPU spent in each mode.",
},
[]string{"cpu", "mode"},
),
}, nil
}
// Expose CPU stats using KVM.
func (c *statCollector) Update(ch chan<- prometheus.Metric) (err error) {
if os.Geteuid() != 0 && os.Getegid() != 2 {
return errors.New("caller should be either root user or kmem group to access /dev/mem")
}
var errbuf *C.char
kd := C.kvm_open(nil, nil, nil, C.O_RDONLY, errbuf)
if errbuf != nil {
return errors.New("failed to call kvm_open()")
}
defer C.kvm_close(kd)
ncpus := C.kvm_getncpus(kd)
for i := 0; i < int(ncpus); i++ {
pcpu := C.kvm_getpcpu(kd, C.int(i))
cp_time := ((*C.struct_pcpu)(unsafe.Pointer(pcpu))).pc_cp_time
c.cpu.With(prometheus.Labels{"cpu": strconv.Itoa(i), "mode": "user"}).Set(float64(cp_time[C.CP_USER]))
c.cpu.With(prometheus.Labels{"cpu": strconv.Itoa(i), "mode": "nice"}).Set(float64(cp_time[C.CP_NICE]))
c.cpu.With(prometheus.Labels{"cpu": strconv.Itoa(i), "mode": "system"}).Set(float64(cp_time[C.CP_SYS]))
c.cpu.With(prometheus.Labels{"cpu": strconv.Itoa(i), "mode": "interrupt"}).Set(float64(cp_time[C.CP_INTR]))
c.cpu.With(prometheus.Labels{"cpu": strconv.Itoa(i), "mode": "idle"}).Set(float64(cp_time[C.CP_IDLE]))
}
c.cpu.Collect(ch)
return err
}