From 2ebd8075848b52619886fd894f830dcaba5e91bd Mon Sep 17 00:00:00 2001
From: Johannes Ziemke <github@5pi.de>
Date: Tue, 30 Jul 2024 07:56:47 -0500
Subject: [PATCH] Add AIX CPU collector

Signed-off-by: Johannes Ziemke <github@5pi.de>
---
 collector/cpu_aix.go | 76 ++++++++++++++++++++++++++++++++++++++++++++
 go.mod               |  1 +
 2 files changed, 77 insertions(+)
 create mode 100644 collector/cpu_aix.go

diff --git a/collector/cpu_aix.go b/collector/cpu_aix.go
new file mode 100644
index 00000000..9d896e2d
--- /dev/null
+++ b/collector/cpu_aix.go
@@ -0,0 +1,76 @@
+// Copyright 2024 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.
+
+//go:build !nocpu
+// +build !nocpu
+
+package collector
+
+/*
+#include <unistd.h>  // Include the standard Unix header
+#include <errno.h>   // For errno
+*/
+import "C"
+import (
+	"fmt"
+	"log/slog"
+	"strconv"
+
+	"github.com/power-devops/perfstat"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type cpuCollector struct {
+	cpu           typedDesc
+	logger        *slog.Logger
+	tickPerSecond int64
+}
+
+func init() {
+	registerCollector("cpu", defaultEnabled, NewCpuCollector)
+}
+
+func tickPerSecond() (int64, error) {
+	ticks, err := C.sysconf(C._SC_CLK_TCK)
+	if ticks == -1 || err != nil {
+		return 0, fmt.Errorf("failed to get clock ticks per second: %v", err)
+	}
+	return int64(ticks), nil
+}
+
+func NewCpuCollector(logger *slog.Logger) (Collector, error) {
+	ticks, err := tickPerSecond()
+	if err != nil {
+		return nil, err
+	}
+	return &cpuCollector{
+		cpu:           typedDesc{nodeCPUSecondsDesc, prometheus.CounterValue},
+		logger:        logger,
+		tickPerSecond: ticks,
+	}, nil
+}
+
+func (c *cpuCollector) Update(ch chan<- prometheus.Metric) error {
+	stats, err := perfstat.CpuStat()
+	if err != nil {
+		return err
+	}
+
+	for n, stat := range stats {
+		ch <- c.cpu.mustNewConstMetric(float64(stat.User/c.tickPerSecond), strconv.Itoa(n), "user")
+		ch <- c.cpu.mustNewConstMetric(float64(stat.Sys/c.tickPerSecond), strconv.Itoa(n), "system")
+		ch <- c.cpu.mustNewConstMetric(float64(stat.Idle/c.tickPerSecond), strconv.Itoa(n), "idle")
+		ch <- c.cpu.mustNewConstMetric(float64(stat.Wait/c.tickPerSecond), strconv.Itoa(n), "wait")
+	}
+	return nil
+}
diff --git a/go.mod b/go.mod
index f6180440..080f0697 100644
--- a/go.mod
+++ b/go.mod
@@ -20,6 +20,7 @@ require (
 	github.com/mdlayher/netlink v1.7.2
 	github.com/mdlayher/wifi v0.2.0
 	github.com/opencontainers/selinux v1.11.0
+	github.com/power-devops/perfstat v0.0.0-20240221224432-82ca36839d55
 	github.com/prometheus-community/go-runit v0.1.0
 	github.com/prometheus/client_golang v1.20.3
 	github.com/prometheus/client_model v0.6.1