Add OpenBSD CPU collector (#805)

collector/cpu_openbsd.go

@@ -0,0 +1,81 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !nocpu
+
+package collector
+
+import (
+	"strconv"
+	"unsafe"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"golang.org/x/sys/unix"
+)
+
+/*
+#include <sys/param.h>
+#include <sys/sched.h>
+*/
+import "C"
+
+type cpuCollector struct {
+	cpu typedDesc
+}
+
+func init() {
+	registerCollector("cpu", defaultEnabled, NewCpuCollector)
+}
+
+func NewCpuCollector() (Collector, error) {
+	return &cpuCollector{
+		cpu: typedDesc{prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, "cpu", "seconds_total"),
+			"Seconds the CPU spent in each mode.",
+			[]string{"cpu", "mode"}, nil,
+		), prometheus.CounterValue},
+	}, nil
+}
+
+func (c *cpuCollector) Update(ch chan<- prometheus.Metric) (err error) {
+	clockb, err := unix.SysctlRaw("kern.clockrate")
+	if err != nil {
+		return err
+	}
+	clock := *(*C.struct_clockinfo)(unsafe.Pointer(&clockb[0]))
+	hz := float64(clock.stathz)
+
+	ncpus, err := unix.SysctlUint32("hw.ncpu")
+	if err != nil {
+		return err
+	}
+
+	var cp_time [][C.CPUSTATES]C.int64_t
+	for i := 0; i < int(ncpus); i++ {
+		cp_timeb, err := unix.SysctlRaw("kern.cp_time2", i)
+		if err != nil {
+			return err
+		}
+		cp_time = append(cp_time, *(*[C.CPUSTATES]C.int64_t)(unsafe.Pointer(&cp_timeb[0])))
+	}
+
+	for cpu, time := range cp_time {
+		lcpu := strconv.Itoa(cpu)
+		ch <- c.cpu.mustNewConstMetric(float64(time[C.CP_USER])/hz, lcpu, "user")
+		ch <- c.cpu.mustNewConstMetric(float64(time[C.CP_NICE])/hz, lcpu, "nice")
+		ch <- c.cpu.mustNewConstMetric(float64(time[C.CP_SYS])/hz, lcpu, "system")
+		ch <- c.cpu.mustNewConstMetric(float64(time[C.CP_INTR])/hz, lcpu, "interrupt")
+		ch <- c.cpu.mustNewConstMetric(float64(time[C.CP_IDLE])/hz, lcpu, "idle")
+	}
+	return err
+}