From dca74ee3f0215b7f83a91c7316588ffc2f8e2932 Mon Sep 17 00:00:00 2001
From: Andrew Wilkins <axw@elastic.co>
Date: Wed, 16 Sep 2020 17:43:05 +0800
Subject: [PATCH 1/2] libbeat/cmd/instance: report cgroup stats

---
 libbeat/cmd/instance/metrics.go | 80 +++++++++++++++++++++++++++++++++
 1 file changed, 80 insertions(+)

diff --git a/libbeat/cmd/instance/metrics.go b/libbeat/cmd/instance/metrics.go
index 54cd3ab55d83..be612dab6612 100644
--- a/libbeat/cmd/instance/metrics.go
+++ b/libbeat/cmd/instance/metrics.go
@@ -28,6 +28,7 @@ import (
 	"github.com/elastic/beats/v7/libbeat/metric/system/cpu"
 	"github.com/elastic/beats/v7/libbeat/metric/system/process"
 	"github.com/elastic/beats/v7/libbeat/monitoring"
+	"github.com/elastic/gosigar/cgroup"
 )
 
 var (
@@ -58,6 +59,9 @@ func setupMetrics(name string) error {
 	monitoring.NewFunc(beatMetrics, "memstats", reportMemStats, monitoring.Report)
 	monitoring.NewFunc(beatMetrics, "cpu", reportBeatCPU, monitoring.Report)
 	monitoring.NewFunc(beatMetrics, "runtime", reportRuntime, monitoring.Report)
+	if runtime.GOOS == "linux" {
+		monitoring.NewFunc(beatMetrics, "cgroup", reportBeatCgroups, monitoring.Report)
+	}
 
 	setupPlatformSpecificMetrics()
 
@@ -254,3 +258,79 @@ func reportRuntime(_ monitoring.Mode, V monitoring.Visitor) {
 
 	monitoring.ReportInt(V, "goroutines", int64(runtime.NumGoroutine()))
 }
+
+func reportBeatCgroups(_ monitoring.Mode, V monitoring.Visitor) {
+	V.OnRegistryStart()
+	defer V.OnRegistryFinished()
+
+	pid, err := process.GetSelfPid()
+	if err != nil {
+		logp.Err("error getting PID for self process: %v", err)
+		return
+	}
+
+	cgroups, err := cgroup.NewReader("", true)
+	if err != nil {
+		if err == cgroup.ErrCgroupsMissing {
+			logp.Warn("cgroup data collection disabled: %v", err)
+		} else {
+			logp.Err("cgroup data collection disabled: %v", err)
+		}
+		return
+	}
+	selfStats, err := cgroups.GetStatsForProcess(pid)
+	if err != nil {
+		logp.Err("error getting group status: %v", err)
+		return
+	}
+
+	if cpu := selfStats.CPU; cpu != nil {
+		monitoring.ReportNamespace(V, "cpu", func() {
+			if cpu.ID != "" {
+				monitoring.ReportString(V, "id", cpu.ID)
+			}
+			monitoring.ReportNamespace(V, "cfs", func() {
+				monitoring.ReportNamespace(V, "period", func() {
+					monitoring.ReportInt(V, "us", int64(cpu.CFS.PeriodMicros))
+				})
+				monitoring.ReportNamespace(V, "quota", func() {
+					monitoring.ReportInt(V, "us", int64(cpu.CFS.QuotaMicros))
+				})
+			})
+			monitoring.ReportNamespace(V, "stats", func() {
+				monitoring.ReportInt(V, "periods", int64(cpu.Stats.Periods))
+				monitoring.ReportNamespace(V, "throttled", func() {
+					monitoring.ReportInt(V, "periods", int64(cpu.Stats.ThrottledPeriods))
+					monitoring.ReportInt(V, "ns", int64(cpu.Stats.ThrottledTimeNanos))
+				})
+			})
+		})
+	}
+
+	if cpuacct := selfStats.CPUAccounting; cpuacct != nil {
+		monitoring.ReportNamespace(V, "cpuacct", func() {
+			if cpuacct.ID != "" {
+				monitoring.ReportString(V, "id", cpuacct.ID)
+			}
+			monitoring.ReportNamespace(V, "total", func() {
+				monitoring.ReportInt(V, "ns", int64(cpuacct.TotalNanos))
+			})
+		})
+	}
+
+	if memory := selfStats.Memory; memory != nil {
+		monitoring.ReportNamespace(V, "memory", func() {
+			if memory.ID != "" {
+				monitoring.ReportString(V, "id", memory.ID)
+			}
+			monitoring.ReportNamespace(V, "mem", func() {
+				monitoring.ReportNamespace(V, "limit", func() {
+					monitoring.ReportInt(V, "bytes", int64(memory.Mem.Limit))
+				})
+				monitoring.ReportNamespace(V, "usage", func() {
+					monitoring.ReportInt(V, "bytes", int64(memory.Mem.Usage))
+				})
+			})
+		})
+	}
+}

From 69cc63bdb7a0a7bc8c4804659635c9de62e5b50e Mon Sep 17 00:00:00 2001
From: Andrew Wilkins <axw@elastic.co>
Date: Thu, 24 Sep 2020 17:40:26 +0800
Subject: [PATCH 2/2] move cgroup metrics registration

---
 libbeat/cmd/instance/metrics.go | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/libbeat/cmd/instance/metrics.go b/libbeat/cmd/instance/metrics.go
index be612dab6612..fa0d42bbeafd 100644
--- a/libbeat/cmd/instance/metrics.go
+++ b/libbeat/cmd/instance/metrics.go
@@ -59,9 +59,6 @@ func setupMetrics(name string) error {
 	monitoring.NewFunc(beatMetrics, "memstats", reportMemStats, monitoring.Report)
 	monitoring.NewFunc(beatMetrics, "cpu", reportBeatCPU, monitoring.Report)
 	monitoring.NewFunc(beatMetrics, "runtime", reportRuntime, monitoring.Report)
-	if runtime.GOOS == "linux" {
-		monitoring.NewFunc(beatMetrics, "cgroup", reportBeatCgroups, monitoring.Report)
-	}
 
 	setupPlatformSpecificMetrics()
 
@@ -69,10 +66,15 @@ func setupMetrics(name string) error {
 }
 
 func setupPlatformSpecificMetrics() {
+	switch runtime.GOOS {
+	case "linux":
+		monitoring.NewFunc(beatMetrics, "cgroup", reportBeatCgroups, monitoring.Report)
+	case "windows":
+		setupWindowsHandlesMetrics()
+	}
+
 	if runtime.GOOS != "windows" {
 		monitoring.NewFunc(systemMetrics, "load", reportSystemLoadAverage, monitoring.Report)
-	} else {
-		setupWindowsHandlesMetrics()
 	}
 
 	setupLinuxBSDFDMetrics()