1 files changed, 304 insertions, 0 deletions
diff --git a/vendor/github.com/containerd/cgroups/memory.go b/vendor/github.com/containerd/cgroups/memory.go
new file mode 100644
index 000000000..9e2ddf2e4
--- /dev/null
+++ b/vendor/github.com/containerd/cgroups/memory.go
@@ -0,0 +1,304 @@
+package cgroups
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+
+	specs "github.com/opencontainers/runtime-spec/specs-go"
+)
+
+func NewMemory(root string) *memoryController {
+	return &memoryController{
+		root: filepath.Join(root, string(Memory)),
+	}
+}
+
+type memoryController struct {
+	root string
+}
+
+func (m *memoryController) Name() Name {
+	return Memory
+}
+
+func (m *memoryController) Path(path string) string {
+	return filepath.Join(m.root, path)
+}
+
+func (m *memoryController) Create(path string, resources *specs.LinuxResources) error {
+	if err := os.MkdirAll(m.Path(path), defaultDirPerm); err != nil {
+		return err
+	}
+	if resources.Memory == nil {
+		return nil
+	}
+	if resources.Memory.Kernel != nil {
+		// Check if kernel memory is enabled
+		// We have to limit the kernel memory here as it won't be accounted at all
+		// until a limit is set on the cgroup and limit cannot be set once the
+		// cgroup has children, or if there are already tasks in the cgroup.
+		for _, i := range []int64{1, -1} {
+			if err := ioutil.WriteFile(
+				filepath.Join(m.Path(path), "memory.kmem.limit_in_bytes"),
+				[]byte(strconv.FormatInt(i, 10)),
+				defaultFilePerm,
+			); err != nil {
+				return checkEBUSY(err)
+			}
+		}
+	}
+	return m.set(path, getMemorySettings(resources))
+}
+
+func (m *memoryController) Update(path string, resources *specs.LinuxResources) error {
+	if resources.Memory == nil {
+		return nil
+	}
+	g := func(v *int64) bool {
+		return v != nil && *v > 0
+	}
+	settings := getMemorySettings(resources)
+	if g(resources.Memory.Limit) && g(resources.Memory.Swap) {
+		// if the updated swap value is larger than the current memory limit set the swap changes first
+		// then set the memory limit as swap must always be larger than the current limit
+		current, err := readUint(filepath.Join(m.Path(path), "memory.limit_in_bytes"))
+		if err != nil {
+			return err
+		}
+		if current < uint64(*resources.Memory.Swap) {
+			settings[0], settings[1] = settings[1], settings[0]
+		}
+	}
+	return m.set(path, settings)
+}
+
+func (m *memoryController) Stat(path string, stats *Stats) error {
+	f, err := os.Open(filepath.Join(m.Path(path), "memory.stat"))
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	stats.Memory = &MemoryStat{}
+	if err := m.parseStats(f, stats.Memory); err != nil {
+		return err
+	}
+	for _, t := range []struct {
+		module string
+		entry  *MemoryEntry
+	}{
+		{
+			module: "",
+			entry:  &stats.Memory.Usage,
+		},
+		{
+			module: "memsw",
+			entry:  &stats.Memory.Swap,
+		},
+		{
+			module: "kmem",
+			entry:  &stats.Memory.Kernel,
+		},
+		{
+			module: "kmem.tcp",
+			entry:  &stats.Memory.KernelTCP,
+		},
+	} {
+		for _, tt := range []struct {
+			name  string
+			value *uint64
+		}{
+			{
+				name:  "usage_in_bytes",
+				value: &t.entry.Usage,
+			},
+			{
+				name:  "max_usage_in_bytes",
+				value: &t.entry.Max,
+			},
+			{
+				name:  "failcnt",
+				value: &t.entry.Failcnt,
+			},
+			{
+				name:  "limit_in_bytes",
+				value: &t.entry.Limit,
+			},
+		} {
+			parts := []string{"memory"}
+			if t.module != "" {
+				parts = append(parts, t.module)
+			}
+			parts = append(parts, tt.name)
+			v, err := readUint(filepath.Join(m.Path(path), strings.Join(parts, ".")))
+			if err != nil {
+				return err
+			}
+			*tt.value = v
+		}
+	}
+	return nil
+}
+
+func (m *memoryController) OOMEventFD(path string) (uintptr, error) {
+	root := m.Path(path)
+	f, err := os.Open(filepath.Join(root, "memory.oom_control"))
+	if err != nil {
+		return 0, err
+	}
+	defer f.Close()
+	fd, _, serr := unix.RawSyscall(unix.SYS_EVENTFD2, 0, unix.FD_CLOEXEC, 0)
+	if serr != 0 {
+		return 0, serr
+	}
+	if err := writeEventFD(root, f.Fd(), fd); err != nil {
+		unix.Close(int(fd))
+		return 0, err
+	}
+	return fd, nil
+}
+
+func writeEventFD(root string, cfd, efd uintptr) error {
+	f, err := os.OpenFile(filepath.Join(root, "cgroup.event_control"), os.O_WRONLY, 0)
+	if err != nil {
+		return err
+	}
+	_, err = f.WriteString(fmt.Sprintf("%d %d", efd, cfd))
+	f.Close()
+	return err
+}
+
+func (m *memoryController) parseStats(r io.Reader, stat *MemoryStat) error {
+	var (
+		raw  = make(map[string]uint64)
+		sc   = bufio.NewScanner(r)
+		line int
+	)
+	for sc.Scan() {
+		if err := sc.Err(); err != nil {
+			return err
+		}
+		key, v, err := parseKV(sc.Text())
+		if err != nil {
+			return fmt.Errorf("%d: %v", line, err)
+		}
+		raw[key] = v
+		line++
+	}
+	stat.Cache = raw["cache"]
+	stat.RSS = raw["rss"]
+	stat.RSSHuge = raw["rss_huge"]
+	stat.MappedFile = raw["mapped_file"]
+	stat.Dirty = raw["dirty"]
+	stat.Writeback = raw["writeback"]
+	stat.PgPgIn = raw["pgpgin"]
+	stat.PgPgOut = raw["pgpgout"]
+	stat.PgFault = raw["pgfault"]
+	stat.PgMajFault = raw["pgmajfault"]
+	stat.InactiveAnon = raw["inactive_anon"]
+	stat.ActiveAnon = raw["active_anon"]
+	stat.InactiveFile = raw["inactive_file"]
+	stat.ActiveFile = raw["active_file"]
+	stat.Unevictable = raw["unevictable"]
+	stat.HierarchicalMemoryLimit = raw["hierarchical_memory_limit"]
+	stat.HierarchicalSwapLimit = raw["hierarchical_memsw_limit"]
+	stat.TotalCache = raw["total_cache"]
+	stat.TotalRSS = raw["total_rss"]
+	stat.TotalRSSHuge = raw["total_rss_huge"]
+	stat.TotalMappedFile = raw["total_mapped_file"]
+	stat.TotalDirty = raw["total_dirty"]
+	stat.TotalWriteback = raw["total_writeback"]
+	stat.TotalPgPgIn = raw["total_pgpgin"]
+	stat.TotalPgPgOut = raw["total_pgpgout"]
+	stat.TotalPgFault = raw["total_pgfault"]
+	stat.TotalPgMajFault = raw["total_pgmajfault"]
+	stat.TotalInactiveAnon = raw["total_inactive_anon"]
+	stat.TotalActiveAnon = raw["total_active_anon"]
+	stat.TotalInactiveFile = raw["total_inactive_file"]
+	stat.TotalActiveFile = raw["total_active_file"]
+	stat.TotalUnevictable = raw["total_unevictable"]
+	return nil
+}
+
+func (m *memoryController) set(path string, settings []memorySettings) error {
+	for _, t := range settings {
+		if t.value != nil {
+			if err := ioutil.WriteFile(
+				filepath.Join(m.Path(path), fmt.Sprintf("memory.%s", t.name)),
+				[]byte(strconv.FormatInt(*t.value, 10)),
+				defaultFilePerm,
+			); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+type memorySettings struct {
+	name  string
+	value *int64
+}
+
+func getMemorySettings(resources *specs.LinuxResources) []memorySettings {
+	mem := resources.Memory
+	var swappiness *int64
+	if mem.Swappiness != nil {
+		v := int64(*mem.Swappiness)
+		swappiness = &v
+	}
+	return []memorySettings{
+		{
+			name:  "limit_in_bytes",
+			value: mem.Limit,
+		},
+		{
+			name:  "memsw.limit_in_bytes",
+			value: mem.Swap,
+		},
+		{
+			name:  "kmem.limit_in_bytes",
+			value: mem.Kernel,
+		},
+		{
+			name:  "kmem.tcp.limit_in_bytes",
+			value: mem.KernelTCP,
+		},
+		{
+			name:  "oom_control",
+			value: getOomControlValue(mem),
+		},
+		{
+			name:  "swappiness",
+			value: swappiness,
+		},
+	}
+}
+
+func checkEBUSY(err error) error {
+	if pathErr, ok := err.(*os.PathError); ok {
+		if errNo, ok := pathErr.Err.(syscall.Errno); ok {
+			if errNo == unix.EBUSY {
+				return fmt.Errorf(
+					"failed to set memory.kmem.limit_in_bytes, because either tasks have already joined this cgroup or it has children")
+			}
+		}
+	}
+	return err
+}
+
+func getOomControlValue(mem *specs.LinuxMemory) *int64 {
+	if mem.DisableOOMKiller != nil && *mem.DisableOOMKiller {
+		i := int64(1)
+		return &i
+	}
+	return nil
+}