diff --git a/pkg/cgroups/cgroups.go b/pkg/cgroups/cgroups.go
index b9318f99e7..1e96caa7e3 100644
--- a/pkg/cgroups/cgroups.go
+++ b/pkg/cgroups/cgroups.go
@@ -5,10 +5,23 @@ import (
"fmt"
"github.com/dotcloud/docker/pkg/mount"
"io"
+ "io/ioutil"
"os"
+ "path/filepath"
+ "strconv"
"strings"
)
+type Cgroup struct {
+ Name string `json:"name,omitempty"`
+ Parent string `json:"parent,omitempty"`
+
+ DeviceAccess bool `json:"device_access,omitempty"` // name of parent cgroup or slice
+ Memory int64 `json:"memory,omitempty"` // Memory limit (in bytes)
+ MemorySwap int64 `json:"memory_swap,omitempty"` // Total memory usage (memory + swap); set `-1' to disable swap
+ CpuShares int64 `json:"cpu_shares,omitempty"` // CPU shares (relative weight vs. other containers)
+}
+
// https://www.kernel.org/doc/Documentation/cgroups/cgroups.txt
func FindCgroupMountpoint(subsystem string) (string, error) {
mounts, err := mount.GetMounts()
@@ -25,7 +38,6 @@ func FindCgroupMountpoint(subsystem string) (string, error) {
}
}
}
-
return "", fmt.Errorf("cgroup mountpoint not found for %s", subsystem)
}
@@ -50,9 +62,50 @@ func GetInitCgroupDir(subsystem string) (string, error) {
return parseCgroupFile(subsystem, f)
}
+func (c *Cgroup) Path(root, subsystem string) (string, error) {
+ cgroup := c.Name
+ if c.Parent != "" {
+ cgroup = filepath.Join(c.Parent, cgroup)
+ }
+ initPath, err := GetInitCgroupDir(subsystem)
+ if err != nil {
+ return "", err
+ }
+ return filepath.Join(root, subsystem, initPath, cgroup), nil
+}
+
+func (c *Cgroup) Join(root, subsystem string, pid int) (string, error) {
+ path, err := c.Path(root, subsystem)
+ if err != nil {
+ return "", err
+ }
+ if err := os.MkdirAll(path, 0755); err != nil && !os.IsExist(err) {
+ return "", err
+ }
+ if err := writeFile(path, "tasks", strconv.Itoa(pid)); err != nil {
+ return "", err
+ }
+ return path, nil
+}
+
+func (c *Cgroup) Cleanup(root string) error {
+ get := func(subsystem string) string {
+ path, _ := c.Path(root, subsystem)
+ return path
+ }
+
+ for _, path := range []string{
+ get("memory"),
+ get("devices"),
+ get("cpu"),
+ } {
+ os.RemoveAll(path)
+ }
+ return nil
+}
+
func parseCgroupFile(subsystem string, r io.Reader) (string, error) {
s := bufio.NewScanner(r)
-
for s.Scan() {
if err := s.Err(); err != nil {
return "", err
@@ -67,3 +120,7 @@ func parseCgroupFile(subsystem string, r io.Reader) (string, error) {
}
return "", fmt.Errorf("cgroup '%s' not found in /proc/self/cgroup", subsystem)
}
+
+func writeFile(dir, file, data string) error {
+ return ioutil.WriteFile(filepath.Join(dir, file), []byte(data), 0700)
+}
diff --git a/pkg/libcontainer/cgroup/cgroup.go b/pkg/libcontainer/cgroup/cgroup.go
index e30262ca50..5f27ac3ffb 100644
--- a/pkg/libcontainer/cgroup/cgroup.go
+++ b/pkg/libcontainer/cgroup/cgroup.go
@@ -10,71 +10,46 @@ import (
"strconv"
)
-// We have two implementation of cgroups support, one is based on
-// systemd and the dbus api, and one is based on raw cgroup fs operations
-// following the pre-single-writer model docs at:
-// http://www.freedesktop.org/wiki/Software/systemd/PaxControlGroups/
-const (
- cgroupRoot = "/sys/fs/cgroup"
-)
-
-func useSystemd() bool {
- return false
-}
-
-func applyCgroupSystemd(container *libcontainer.Container, pid int) error {
- return fmt.Errorf("not supported yet")
-}
-
-func writeFile(dir, file, data string) error {
- return ioutil.WriteFile(filepath.Join(dir, file), []byte(data), 0700)
-}
-
-func getCgroup(subsystem string, container *libcontainer.Container) (string, error) {
- cgroup := container.CgroupName
- if container.CgroupParent != "" {
- cgroup = filepath.Join(container.CgroupParent, cgroup)
+func ApplyCgroup(container *libcontainer.Container, pid int) (err error) {
+ if container.Cgroups == nil {
+ return nil
}
- initPath, err := cgroups.GetInitCgroupDir(subsystem)
+ // We have two implementation of cgroups support, one is based on
+ // systemd and the dbus api, and one is based on raw cgroup fs operations
+ // following the pre-single-writer model docs at:
+ // http://www.freedesktop.org/wiki/Software/systemd/PaxControlGroups/
+ //
+ // we can pick any subsystem to find the root
+ cgroupRoot, err := cgroups.FindCgroupMountpoint("memory")
if err != nil {
- return "", err
+ return err
}
-
- path := filepath.Join(cgroupRoot, subsystem, initPath, cgroup)
-
- return path, nil
-}
-
-func joinCgroup(subsystem string, container *libcontainer.Container, pid int) (string, error) {
- path, err := getCgroup(subsystem, container)
- if err != nil {
- return "", err
- }
-
- if err := os.MkdirAll(path, 0755); err != nil && !os.IsExist(err) {
- return "", err
- }
-
- if err := writeFile(path, "tasks", strconv.Itoa(pid)); err != nil {
- return "", err
- }
-
- return path, nil
-}
-
-func applyCgroupRaw(container *libcontainer.Container, pid int) (retErr error) {
+ cgroupRoot = filepath.Dir(cgroupRoot)
if _, err := os.Stat(cgroupRoot); err != nil {
return fmt.Errorf("cgroups fs not found")
}
+ if err := setupDevices(container, cgroupRoot, pid); err != nil {
+ return err
+ }
+ if err := setupMemory(container, cgroupRoot, pid); err != nil {
+ return err
+ }
+ if err := setupCpu(container, cgroupRoot, pid); err != nil {
+ return err
+ }
+ return nil
+}
- if !container.DeviceAccess {
- dir, err := joinCgroup("devices", container, pid)
+func setupDevices(container *libcontainer.Container, cgroupRoot string, pid int) (err error) {
+ if !container.Cgroups.DeviceAccess {
+ dir, err := container.Cgroups.Join(cgroupRoot, "devices", pid)
if err != nil {
return err
}
+
defer func() {
- if retErr != nil {
+ if err != nil {
os.RemoveAll(dir)
}
}()
@@ -113,65 +88,53 @@ func applyCgroupRaw(container *libcontainer.Container, pid int) (retErr error) {
}
}
}
+ return nil
+}
- if container.Memory != 0 || container.MemorySwap != 0 {
- dir, err := joinCgroup("memory", container, pid)
+func setupMemory(container *libcontainer.Container, cgroupRoot string, pid int) (err error) {
+ if container.Cgroups.Memory != 0 || container.Cgroups.MemorySwap != 0 {
+ dir, err := container.Cgroups.Join(cgroupRoot, "memory", pid)
if err != nil {
return err
}
defer func() {
- if retErr != nil {
+ if err != nil {
os.RemoveAll(dir)
}
}()
- if container.Memory != 0 {
- if err := writeFile(dir, "memory.limit_in_bytes", strconv.FormatInt(container.Memory, 10)); err != nil {
+ if container.Cgroups.Memory != 0 {
+ if err := writeFile(dir, "memory.limit_in_bytes", strconv.FormatInt(container.Cgroups.Memory, 10)); err != nil {
return err
}
- if err := writeFile(dir, "memory.soft_limit_in_bytes", strconv.FormatInt(container.Memory, 10)); err != nil {
+ if err := writeFile(dir, "memory.soft_limit_in_bytes", strconv.FormatInt(container.Cgroups.Memory, 10)); err != nil {
return err
}
}
- if container.MemorySwap != 0 {
- if err := writeFile(dir, "memory.memsw.limit_in_bytes", strconv.FormatInt(container.MemorySwap, 10)); err != nil {
+ if container.Cgroups.MemorySwap != 0 {
+ if err := writeFile(dir, "memory.memsw.limit_in_bytes", strconv.FormatInt(container.Cgroups.MemorySwap, 10)); err != nil {
return err
}
}
}
+ return nil
+}
+func setupCpu(container *libcontainer.Container, cgroupRoot string, pid int) (err error) {
// We always want to join the cpu group, to allow fair cpu scheduling
// on a container basis
- dir, err := joinCgroup("cpu", container, pid)
+ dir, err := container.Cgroups.Join(cgroupRoot, "cpu", pid)
if err != nil {
return err
}
- if container.CpuShares != 0 {
- if err := writeFile(dir, "cpu.shares", strconv.FormatInt(container.CpuShares, 10)); err != nil {
+ if container.Cgroups.CpuShares != 0 {
+ if err := writeFile(dir, "cpu.shares", strconv.FormatInt(container.Cgroups.CpuShares, 10)); err != nil {
return err
}
}
return nil
}
-func CleanupCgroup(container *libcontainer.Container) error {
- path, _ := getCgroup("memory", container)
- os.RemoveAll(path)
- path, _ = getCgroup("devices", container)
- os.RemoveAll(path)
- path, _ = getCgroup("cpu", container)
- os.RemoveAll(path)
- return nil
-}
-
-func ApplyCgroup(container *libcontainer.Container, pid int) error {
- if container.CgroupName == "" {
- return nil
- }
-
- if useSystemd() {
- return applyCgroupSystemd(container, pid)
- } else {
- return applyCgroupRaw(container, pid)
- }
+func writeFile(dir, file, data string) error {
+ return ioutil.WriteFile(filepath.Join(dir, file), []byte(data), 0700)
}
diff --git a/pkg/libcontainer/container.go b/pkg/libcontainer/container.go
index b34ac8b351..4c0e39a798 100644
--- a/pkg/libcontainer/container.go
+++ b/pkg/libcontainer/container.go
@@ -1,23 +1,21 @@
package libcontainer
+import (
+ "github.com/dotcloud/docker/pkg/cgroups"
+)
+
// Container defines configuration options for how a
// container is setup inside a directory and how a process should be executed
type Container struct {
- Hostname string `json:"hostname,omitempty"` // hostname
- ReadonlyFs bool `json:"readonly_fs,omitempty"` // set the containers rootfs as readonly
- User string `json:"user,omitempty"` // user to execute the process as
- WorkingDir string `json:"working_dir,omitempty"` // current working directory
- Env []string `json:"environment,omitempty"` // environment to set
- Namespaces Namespaces `json:"namespaces,omitempty"` // namespaces to apply
- Capabilities Capabilities `json:"capabilities,omitempty"` // capabilities to drop
- Network *Network `json:"network,omitempty"` // nil for host's network stack
-
- CgroupName string `json:"cgroup_name,omitempty"` // name of cgroup
- CgroupParent string `json:"cgroup_parent,omitempty"` // name of parent cgroup or slice
- DeviceAccess bool `json:"device_access,omitempty"` // name of parent cgroup or slice
- Memory int64 `json:"memory,omitempty"` // Memory limit (in bytes)
- MemorySwap int64 `json:"memory_swap,omitempty"` // Total memory usage (memory + swap); set `-1' to disable swap
- CpuShares int64 `json:"cpu_shares,omitempty"` // CPU shares (relative weight vs. other containers)
+ Hostname string `json:"hostname,omitempty"` // hostname
+ ReadonlyFs bool `json:"readonly_fs,omitempty"` // set the containers rootfs as readonly
+ User string `json:"user,omitempty"` // user to execute the process as
+ WorkingDir string `json:"working_dir,omitempty"` // current working directory
+ Env []string `json:"environment,omitempty"` // environment to set
+ Namespaces Namespaces `json:"namespaces,omitempty"` // namespaces to apply
+ Capabilities Capabilities `json:"capabilities,omitempty"` // capabilities to drop
+ Network *Network `json:"network,omitempty"` // nil for host's network stack
+ Cgroups *cgroups.Cgroup `json:"cgroups,omitempty"`
}
// Network defines configuration for a container's networking stack
diff --git a/pkg/libcontainer/container.json b/pkg/libcontainer/container.json
index 3e23600630..2207543bd0 100644
--- a/pkg/libcontainer/container.json
+++ b/pkg/libcontainer/container.json
@@ -35,7 +35,9 @@
"bridge": "docker0",
"mtu": 1500
},
- "cgroup_name": "docker-koye",
- "cgroup_parent": "docker",
- "memory": 524800
+ "cgroups": {
+ "name": "docker-koye",
+ "parent": "docker",
+ "memory": 524800
+ }
}