1 files changed, 166 insertions, 0 deletions
diff --git a/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs/cpuacct.go b/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs/cpuacct.go
new file mode 100644
index 000000000..d3bd7e111
--- /dev/null
+++ b/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs/cpuacct.go
@@ -0,0 +1,166 @@
+package fs
+
+import (
+	"bufio"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/opencontainers/runc/libcontainer/cgroups"
+	"github.com/opencontainers/runc/libcontainer/cgroups/fscommon"
+	"github.com/opencontainers/runc/libcontainer/configs"
+)
+
+const (
+	cgroupCpuacctStat     = "cpuacct.stat"
+	cgroupCpuacctUsageAll = "cpuacct.usage_all"
+
+	nanosecondsInSecond = 1000000000
+
+	userModeColumn              = 1
+	kernelModeColumn            = 2
+	cuacctUsageAllColumnsNumber = 3
+
+	// The value comes from `C.sysconf(C._SC_CLK_TCK)`, and
+	// on Linux it's a constant which is safe to be hard coded,
+	// so we can avoid using cgo here. For details, see:
+	// https://github.com/containerd/cgroups/pull/12
+	clockTicks uint64 = 100
+)
+
+type CpuacctGroup struct{}
+
+func (s *CpuacctGroup) Name() string {
+	return "cpuacct"
+}
+
+func (s *CpuacctGroup) Apply(path string, _ *configs.Resources, pid int) error {
+	return apply(path, pid)
+}
+
+func (s *CpuacctGroup) Set(_ string, _ *configs.Resources) error {
+	return nil
+}
+
+func (s *CpuacctGroup) GetStats(path string, stats *cgroups.Stats) error {
+	if !cgroups.PathExists(path) {
+		return nil
+	}
+	userModeUsage, kernelModeUsage, err := getCpuUsageBreakdown(path)
+	if err != nil {
+		return err
+	}
+
+	totalUsage, err := fscommon.GetCgroupParamUint(path, "cpuacct.usage")
+	if err != nil {
+		return err
+	}
+
+	percpuUsage, err := getPercpuUsage(path)
+	if err != nil {
+		return err
+	}
+
+	percpuUsageInKernelmode, percpuUsageInUsermode, err := getPercpuUsageInModes(path)
+	if err != nil {
+		return err
+	}
+
+	stats.CpuStats.CpuUsage.TotalUsage = totalUsage
+	stats.CpuStats.CpuUsage.PercpuUsage = percpuUsage
+	stats.CpuStats.CpuUsage.PercpuUsageInKernelmode = percpuUsageInKernelmode
+	stats.CpuStats.CpuUsage.PercpuUsageInUsermode = percpuUsageInUsermode
+	stats.CpuStats.CpuUsage.UsageInUsermode = userModeUsage
+	stats.CpuStats.CpuUsage.UsageInKernelmode = kernelModeUsage
+	return nil
+}
+
+// Returns user and kernel usage breakdown in nanoseconds.
+func getCpuUsageBreakdown(path string) (uint64, uint64, error) {
+	var userModeUsage, kernelModeUsage uint64
+	const (
+		userField   = "user"
+		systemField = "system"
+		file        = cgroupCpuacctStat
+	)
+
+	// Expected format:
+	// user <usage in ticks>
+	// system <usage in ticks>
+	data, err := cgroups.ReadFile(path, file)
+	if err != nil {
+		return 0, 0, err
+	}
+	// TODO: use strings.SplitN instead.
+	fields := strings.Fields(data)
+	if len(fields) < 4 || fields[0] != userField || fields[2] != systemField {
+		return 0, 0, malformedLine(path, file, data)
+	}
+	if userModeUsage, err = strconv.ParseUint(fields[1], 10, 64); err != nil {
+		return 0, 0, &parseError{Path: path, File: file, Err: err}
+	}
+	if kernelModeUsage, err = strconv.ParseUint(fields[3], 10, 64); err != nil {
+		return 0, 0, &parseError{Path: path, File: file, Err: err}
+	}
+
+	return (userModeUsage * nanosecondsInSecond) / clockTicks, (kernelModeUsage * nanosecondsInSecond) / clockTicks, nil
+}
+
+func getPercpuUsage(path string) ([]uint64, error) {
+	const file = "cpuacct.usage_percpu"
+	percpuUsage := []uint64{}
+	data, err := cgroups.ReadFile(path, file)
+	if err != nil {
+		return percpuUsage, err
+	}
+	// TODO: use strings.SplitN instead.
+	for _, value := range strings.Fields(data) {
+		value, err := strconv.ParseUint(value, 10, 64)
+		if err != nil {
+			return percpuUsage, &parseError{Path: path, File: file, Err: err}
+		}
+		percpuUsage = append(percpuUsage, value)
+	}
+	return percpuUsage, nil
+}
+
+func getPercpuUsageInModes(path string) ([]uint64, []uint64, error) {
+	usageKernelMode := []uint64{}
+	usageUserMode := []uint64{}
+	const file = cgroupCpuacctUsageAll
+
+	fd, err := cgroups.OpenFile(path, file, os.O_RDONLY)
+	if os.IsNotExist(err) {
+		return usageKernelMode, usageUserMode, nil
+	} else if err != nil {
+		return nil, nil, err
+	}
+	defer fd.Close()
+
+	scanner := bufio.NewScanner(fd)
+	scanner.Scan() // skipping header line
+
+	for scanner.Scan() {
+		lineFields := strings.SplitN(scanner.Text(), " ", cuacctUsageAllColumnsNumber+1)
+		if len(lineFields) != cuacctUsageAllColumnsNumber {
+			continue
+		}
+
+		usageInKernelMode, err := strconv.ParseUint(lineFields[kernelModeColumn], 10, 64)
+		if err != nil {
+			return nil, nil, &parseError{Path: path, File: file, Err: err}
+		}
+		usageKernelMode = append(usageKernelMode, usageInKernelMode)
+
+		usageInUserMode, err := strconv.ParseUint(lineFields[userModeColumn], 10, 64)
+		if err != nil {
+			return nil, nil, &parseError{Path: path, File: file, Err: err}
+		}
+		usageUserMode = append(usageUserMode, usageInUserMode)
+	}
+	if err := scanner.Err(); err != nil {
+		return nil, nil, &parseError{Path: path, File: file, Err: err}
+	}
+
+	return usageKernelMode, usageUserMode, nil
+}