Add AIX loadavg collector

Signed-off-by: Johannes Ziemke <github@5pi.de>

collector/loadavg.go

@@ -11,8 +11,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-//go:build (darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris) && !noloadavg
-// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+//go:build (darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || aix) && !noloadavg
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris aix
 // +build !noloadavg
 
 package collector

collector/loadavg_aix.go

@@ -0,0 +1,30 @@
+// 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 !noloadavg
+// +build !noloadavg
+
+package collector
+
+import (
+	"github.com/power-devops/perfstat"
+)
+
+func getLoad() ([]float64, error) {
+	stat, err := perfstat.CpuTotalStat()
+	if err != nil {
+		return nil, err
+	}
+
+	return []float64{float64(stat.LoadAvg1), float64(stat.LoadAvg5), float64(stat.LoadAvg15)}, nil
+}