1 files changed, 361 insertions, 0 deletions
diff --git a/vendor/github.com/containerd/cgroups/blkio.go b/vendor/github.com/containerd/cgroups/blkio.go
new file mode 100644
index 000000000..f59c75bb5
--- /dev/null
+++ b/vendor/github.com/containerd/cgroups/blkio.go
@@ -0,0 +1,361 @@
+/*
+   Copyright The containerd 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.
+*/
+
+package cgroups
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	v1 "github.com/containerd/cgroups/stats/v1"
+	specs "github.com/opencontainers/runtime-spec/specs-go"
+)
+
+// NewBlkio returns a Blkio controller given the root folder of cgroups.
+// It may optionally accept other configuration options, such as ProcRoot(path)
+func NewBlkio(root string, options ...func(controller *blkioController)) *blkioController {
+	ctrl := &blkioController{
+		root:     filepath.Join(root, string(Blkio)),
+		procRoot: "/proc",
+	}
+	for _, opt := range options {
+		opt(ctrl)
+	}
+	return ctrl
+}
+
+// ProcRoot overrides the default location of the "/proc" filesystem
+func ProcRoot(path string) func(controller *blkioController) {
+	return func(c *blkioController) {
+		c.procRoot = path
+	}
+}
+
+type blkioController struct {
+	root     string
+	procRoot string
+}
+
+func (b *blkioController) Name() Name {
+	return Blkio
+}
+
+func (b *blkioController) Path(path string) string {
+	return filepath.Join(b.root, path)
+}
+
+func (b *blkioController) Create(path string, resources *specs.LinuxResources) error {
+	if err := os.MkdirAll(b.Path(path), defaultDirPerm); err != nil {
+		return err
+	}
+	if resources.BlockIO == nil {
+		return nil
+	}
+	for _, t := range createBlkioSettings(resources.BlockIO) {
+		if t.value != nil {
+			if err := retryingWriteFile(
+				filepath.Join(b.Path(path), "blkio."+t.name),
+				t.format(t.value),
+				defaultFilePerm,
+			); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+func (b *blkioController) Update(path string, resources *specs.LinuxResources) error {
+	return b.Create(path, resources)
+}
+
+func (b *blkioController) Stat(path string, stats *v1.Metrics) error {
+	stats.Blkio = &v1.BlkIOStat{}
+
+	var settings []blkioStatSettings
+
+	// Try to read CFQ stats available on all CFQ enabled kernels first
+	if _, err := os.Lstat(filepath.Join(b.Path(path), "blkio.io_serviced_recursive")); err == nil {
+		settings = []blkioStatSettings{
+			{
+				name:  "sectors_recursive",
+				entry: &stats.Blkio.SectorsRecursive,
+			},
+			{
+				name:  "io_service_bytes_recursive",
+				entry: &stats.Blkio.IoServiceBytesRecursive,
+			},
+			{
+				name:  "io_serviced_recursive",
+				entry: &stats.Blkio.IoServicedRecursive,
+			},
+			{
+				name:  "io_queued_recursive",
+				entry: &stats.Blkio.IoQueuedRecursive,
+			},
+			{
+				name:  "io_service_time_recursive",
+				entry: &stats.Blkio.IoServiceTimeRecursive,
+			},
+			{
+				name:  "io_wait_time_recursive",
+				entry: &stats.Blkio.IoWaitTimeRecursive,
+			},
+			{
+				name:  "io_merged_recursive",
+				entry: &stats.Blkio.IoMergedRecursive,
+			},
+			{
+				name:  "time_recursive",
+				entry: &stats.Blkio.IoTimeRecursive,
+			},
+		}
+	}
+
+	f, err := os.Open(filepath.Join(b.procRoot, "partitions"))
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	devices, err := getDevices(f)
+	if err != nil {
+		return err
+	}
+
+	var size int
+	for _, t := range settings {
+		if err := b.readEntry(devices, path, t.name, t.entry); err != nil {
+			return err
+		}
+		size += len(*t.entry)
+	}
+	if size > 0 {
+		return nil
+	}
+
+	// Even the kernel is compiled with the CFQ scheduler, the cgroup may not use
+	// block devices with the CFQ scheduler. If so, we should fallback to throttle.* files.
+	settings = []blkioStatSettings{
+		{
+			name:  "throttle.io_serviced",
+			entry: &stats.Blkio.IoServicedRecursive,
+		},
+		{
+			name:  "throttle.io_service_bytes",
+			entry: &stats.Blkio.IoServiceBytesRecursive,
+		},
+	}
+	for _, t := range settings {
+		if err := b.readEntry(devices, path, t.name, t.entry); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (b *blkioController) readEntry(devices map[deviceKey]string, path, name string, entry *[]*v1.BlkIOEntry) error {
+	f, err := os.Open(filepath.Join(b.Path(path), "blkio."+name))
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	sc := bufio.NewScanner(f)
+	for sc.Scan() {
+		// format: dev type amount
+		fields := strings.FieldsFunc(sc.Text(), splitBlkIOStatLine)
+		if len(fields) < 3 {
+			if len(fields) == 2 && fields[0] == "Total" {
+				// skip total line
+				continue
+			} else {
+				return fmt.Errorf("invalid line found while parsing %s: %s", path, sc.Text())
+			}
+		}
+		major, err := strconv.ParseUint(fields[0], 10, 64)
+		if err != nil {
+			return err
+		}
+		minor, err := strconv.ParseUint(fields[1], 10, 64)
+		if err != nil {
+			return err
+		}
+		op := ""
+		valueField := 2
+		if len(fields) == 4 {
+			op = fields[2]
+			valueField = 3
+		}
+		v, err := strconv.ParseUint(fields[valueField], 10, 64)
+		if err != nil {
+			return err
+		}
+		*entry = append(*entry, &v1.BlkIOEntry{
+			Device: devices[deviceKey{major, minor}],
+			Major:  major,
+			Minor:  minor,
+			Op:     op,
+			Value:  v,
+		})
+	}
+	return sc.Err()
+}
+
+func createBlkioSettings(blkio *specs.LinuxBlockIO) []blkioSettings {
+	settings := []blkioSettings{}
+
+	if blkio.Weight != nil {
+		settings = append(settings,
+			blkioSettings{
+				name:   "weight",
+				value:  blkio.Weight,
+				format: uintf,
+			})
+	}
+	if blkio.LeafWeight != nil {
+		settings = append(settings,
+			blkioSettings{
+				name:   "leaf_weight",
+				value:  blkio.LeafWeight,
+				format: uintf,
+			})
+	}
+	for _, wd := range blkio.WeightDevice {
+		if wd.Weight != nil {
+			settings = append(settings,
+				blkioSettings{
+					name:   "weight_device",
+					value:  wd,
+					format: weightdev,
+				})
+		}
+		if wd.LeafWeight != nil {
+			settings = append(settings,
+				blkioSettings{
+					name:   "leaf_weight_device",
+					value:  wd,
+					format: weightleafdev,
+				})
+		}
+	}
+	for _, t := range []struct {
+		name string
+		list []specs.LinuxThrottleDevice
+	}{
+		{
+			name: "throttle.read_bps_device",
+			list: blkio.ThrottleReadBpsDevice,
+		},
+		{
+			name: "throttle.read_iops_device",
+			list: blkio.ThrottleReadIOPSDevice,
+		},
+		{
+			name: "throttle.write_bps_device",
+			list: blkio.ThrottleWriteBpsDevice,
+		},
+		{
+			name: "throttle.write_iops_device",
+			list: blkio.ThrottleWriteIOPSDevice,
+		},
+	} {
+		for _, td := range t.list {
+			settings = append(settings, blkioSettings{
+				name:   t.name,
+				value:  td,
+				format: throttleddev,
+			})
+		}
+	}
+	return settings
+}
+
+type blkioSettings struct {
+	name   string
+	value  interface{}
+	format func(v interface{}) []byte
+}
+
+type blkioStatSettings struct {
+	name  string
+	entry *[]*v1.BlkIOEntry
+}
+
+func uintf(v interface{}) []byte {
+	return []byte(strconv.FormatUint(uint64(*v.(*uint16)), 10))
+}
+
+func weightdev(v interface{}) []byte {
+	wd := v.(specs.LinuxWeightDevice)
+	return []byte(fmt.Sprintf("%d:%d %d", wd.Major, wd.Minor, *wd.Weight))
+}
+
+func weightleafdev(v interface{}) []byte {
+	wd := v.(specs.LinuxWeightDevice)
+	return []byte(fmt.Sprintf("%d:%d %d", wd.Major, wd.Minor, *wd.LeafWeight))
+}
+
+func throttleddev(v interface{}) []byte {
+	td := v.(specs.LinuxThrottleDevice)
+	return []byte(fmt.Sprintf("%d:%d %d", td.Major, td.Minor, td.Rate))
+}
+
+func splitBlkIOStatLine(r rune) bool {
+	return r == ' ' || r == ':'
+}
+
+type deviceKey struct {
+	major, minor uint64
+}
+
+// getDevices makes a best effort attempt to read all the devices into a map
+// keyed by major and minor number. Since devices may be mapped multiple times,
+// we err on taking the first occurrence.
+func getDevices(r io.Reader) (map[deviceKey]string, error) {
+
+	var (
+		s       = bufio.NewScanner(r)
+		devices = make(map[deviceKey]string)
+	)
+	for i := 0; s.Scan(); i++ {
+		if i < 2 {
+			continue
+		}
+		fields := strings.Fields(s.Text())
+		major, err := strconv.Atoi(fields[0])
+		if err != nil {
+			return nil, err
+		}
+		minor, err := strconv.Atoi(fields[1])
+		if err != nil {
+			return nil, err
+		}
+		key := deviceKey{
+			major: uint64(major),
+			minor: uint64(minor),
+		}
+		if _, ok := devices[key]; ok {
+			continue
+		}
+		devices[key] = filepath.Join("/dev", fields[3])
+	}
+	return devices, s.Err()
+}