Add code 3.2

cgroups/cgroup_manager.go

@@ -0,0 +1,45 @@
+package cgroups
+
+import (
+	"github.com/xianlubird/mydocker/cgroups/subsystems"
+	"github.com/Sirupsen/logrus"
+)
+
+type CgroupManager struct {
+	// cgroup在hierarchy中的路径 相当于创建的cgroup目录相对于root cgroup目录的路径
+	Path     string
+	// 资源配置
+	Resource *subsystems.ResourceConfig
+}
+
+func NewCgroupManager(path string) *CgroupManager {
+	return &CgroupManager{
+		Path: path,
+	}
+}
+
+// 将进程pid加入到这个cgroup中
+func (c *CgroupManager) Apply(pid int) error {
+	for _, subSysIns := range(subsystems.SubsystemsIns) {
+		subSysIns.Apply(c.Path, pid)
+	}
+	return nil
+}
+
+// 设置cgroup资源限制
+func (c *CgroupManager) Set(res *subsystems.ResourceConfig) error {
+	for _, subSysIns := range(subsystems.SubsystemsIns) {
+		subSysIns.Set(c.Path, res)
+	}
+	return nil
+}
+
+//释放cgroup
+func (c *CgroupManager) Destroy() error {
+	for _, subSysIns := range(subsystems.SubsystemsIns) {
+		if err := subSysIns.Remove(c.Path); err != nil {
+			logrus.Warnf("remove cgroup fail %v", err)
+		}
+	}
+	return nil
+}

cgroups/subsystems/cpu.go

@@ -0,0 +1,48 @@
+package subsystems
+import (
+	"fmt"
+	"io/ioutil"
+	"path"
+	"os"
+	"strconv"
+)
+
+type CpuSubSystem struct {
+}
+
+func (s *CpuSubSystem) Set(cgroupPath string, res *ResourceConfig) error {
+	if subsysCgroupPath, err := GetCgroupPath(s.Name(), cgroupPath, true); err == nil {
+		if res.CpuShare != "" {
+			if err := ioutil.WriteFile(path.Join(subsysCgroupPath, "cpu.shares"), []byte(res.CpuShare), 0644); err != nil {
+				return fmt.Errorf("set cgroup cpu share fail %v", err)
+			}
+		}
+		return nil
+	} else {
+		return err
+	}
+}
+
+func (s *CpuSubSystem) Remove(cgroupPath string) error {
+	if subsysCgroupPath, err := GetCgroupPath(s.Name(), cgroupPath, false); err == nil {
+		return os.RemoveAll(subsysCgroupPath)
+	} else {
+		return err
+	}
+}
+
+func (s *CpuSubSystem)Apply(cgroupPath string, pid int) error {
+	if subsysCgroupPath, err := GetCgroupPath(s.Name(), cgroupPath, false); err == nil {
+		if err := ioutil.WriteFile(path.Join(subsysCgroupPath, "tasks"),  []byte(strconv.Itoa(pid)), 0644); err != nil {
+			return fmt.Errorf("set cgroup proc fail %v", err)
+		}
+		return nil
+	} else {
+		return fmt.Errorf("get cgroup %s error: %v", cgroupPath, err)
+	}
+}
+
+func (s *CpuSubSystem) Name() string {
+	return "cpu"
+}
+

cgroups/subsystems/cpuset.go

@@ -0,0 +1,51 @@
+package subsystems
+
+import(
+	"fmt"
+	"io/ioutil"
+	"path"
+	"os"
+	"strconv"
+)
+
+type CpusetSubSystem struct {
+
+}
+
+func (s *CpusetSubSystem) Set(cgroupPath string, res *ResourceConfig) error {
+	if subsysCgroupPath, err := GetCgroupPath(s.Name(), cgroupPath, true); err == nil {
+		if res.CpuSet != "" {
+			if err := ioutil.WriteFile(path.Join(subsysCgroupPath, "cpuset.cpus"), []byte(res.CpuSet), 0644); err != nil {
+				return fmt.Errorf("set cgroup cpuset fail %v", err)
+			}
+		}
+		return nil
+	} else {
+		return err
+	}
+}
+
+func (s *CpusetSubSystem) Remove(cgroupPath string) error {
+	if subsysCgroupPath, err := GetCgroupPath(s.Name(), cgroupPath, false); err == nil {
+		return os.RemoveAll(subsysCgroupPath)
+	} else {
+		return err
+	}
+}
+
+
+func (s *CpusetSubSystem)Apply(cgroupPath string, pid int) error {
+	if subsysCgroupPath, err := GetCgroupPath(s.Name(), cgroupPath, false); err == nil {
+		if err := ioutil.WriteFile(path.Join(subsysCgroupPath, "tasks"),  []byte(strconv.Itoa(pid)), 0644); err != nil {
+			return fmt.Errorf("set cgroup proc fail %v", err)
+		}
+		return nil
+	} else {
+		return fmt.Errorf("get cgroup %s error: %v", cgroupPath, err)
+	}
+}
+
+
+func (s *CpusetSubSystem) Name() string {
+	return "cpuset"
+}

cgroups/subsystems/memory.go

@@ -0,0 +1,51 @@
+package subsystems
+
+import(
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"strconv"
+)
+
+type MemorySubSystem struct {
+}
+
+func (s *MemorySubSystem) Set(cgroupPath string, res *ResourceConfig) error {
+	if subsysCgroupPath, err := GetCgroupPath(s.Name(), cgroupPath, true); err == nil {
+		if res.MemoryLimit != "" {
+			if err := ioutil.WriteFile(path.Join(subsysCgroupPath, "memory.limit_in_bytes"), []byte(res.MemoryLimit), 0644); err != nil {
+				return fmt.Errorf("set cgroup memory fail %v", err)
+			}
+		}
+		return nil
+	} else {
+		return err
+	}
+
+}
+
+func (s *MemorySubSystem) Remove(cgroupPath string) error {
+	if subsysCgroupPath, err := GetCgroupPath(s.Name(), cgroupPath, false); err == nil {
+		return os.RemoveAll(subsysCgroupPath)
+	} else {
+		return err
+	}
+}
+
+
+func (s *MemorySubSystem) Apply(cgroupPath string, pid int) error {
+	if subsysCgroupPath, err := GetCgroupPath(s.Name(), cgroupPath, false); err == nil {
+		if err := ioutil.WriteFile(path.Join(subsysCgroupPath, "tasks"),  []byte(strconv.Itoa(pid)), 0644); err != nil {
+			return fmt.Errorf("set cgroup proc fail %v", err)
+		}
+		return nil
+	} else {
+		return fmt.Errorf("get cgroup %s error: %v", cgroupPath, err)
+	}
+}
+
+
+func (s *MemorySubSystem) Name() string {
+	return "memory"
+}

cgroups/subsystems/memory_test.go

@@ -0,0 +1,33 @@
+package subsystems
+
+import(
+	"testing"
+	"os"
+	"path"
+)
+
+func TestMemoryCgroup(t *testing.T) {
+	memSubSys := MemorySubSystem{}
+	resConfig := ResourceConfig{
+		MemoryLimit: "1000m",
+	}
+	testCgroup := "testmemlimit"
+
+	if err := memSubSys.Set(testCgroup, &resConfig); err != nil {
+		t.Fatalf("cgroup fail %v", err)
+	}
+	stat, _ := os.Stat(path.Join(FindCgroupMountpoint("memory"), testCgroup))
+	t.Logf("cgroup stats: %+v", stat)
+
+	if err := memSubSys.Apply(testCgroup, os.Getpid()); err != nil {
+		t.Fatalf("cgroup Apply %v", err)
+	}
+	//将进程移回到根Cgroup节点
+	if err := memSubSys.Apply("", os.Getpid()); err != nil {
+		t.Fatalf("cgroup Apply %v", err)
+	}
+
+	if err := memSubSys.Remove(testCgroup); err != nil {
+		t.Fatalf("cgroup remove %v", err)
+	}
+}

cgroups/subsystems/subsystem.go

@@ -0,0 +1,22 @@
+package subsystems
+
+type ResourceConfig struct {
+	MemoryLimit string
+	CpuShare    string
+	CpuSet      string
+}
+
+type Subsystem interface {
+	Name() string
+	Set(path string, res *ResourceConfig) error
+	Apply(path string, pid int) error
+	Remove(path string) error
+}
+
+var (
+	SubsystemsIns = []Subsystem{
+		&CpusetSubSystem{},
+		&MemorySubSystem{},
+		&CpuSubSystem{},
+	}
+)

cgroups/subsystems/utils.go

@@ -0,0 +1,49 @@
+package subsystems
+
+import (
+	"fmt"
+	"strings"
+	"os"
+	"path"
+	"bufio"
+)
+
+
+func FindCgroupMountpoint(subsystem string) string {
+	f, err := os.Open("/proc/self/mountinfo")
+	if err != nil {
+		return ""
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+		txt := scanner.Text()
+		fields := strings.Split(txt, " ")
+		for _, opt := range strings.Split(fields[len(fields)-1], ",") {
+			if opt == subsystem {
+				return fields[4]
+			}
+		}
+	}
+	if err := scanner.Err(); err != nil {
+		return ""
+	}
+
+	return ""
+}
+
+func GetCgroupPath(subsystem string, cgroupPath string, autoCreate bool) (string, error) {
+	cgroupRoot := FindCgroupMountpoint(subsystem)
+	if _, err := os.Stat(path.Join(cgroupRoot, cgroupPath)); err == nil || (autoCreate && os.IsNotExist(err)) {
+		if os.IsNotExist(err) {
+			if err := os.Mkdir(path.Join(cgroupRoot, cgroupPath), 0755); err == nil {
+			} else {
+				return "", fmt.Errorf("error create cgroup %v", err)
+			}
+		}
+		return path.Join(cgroupRoot, cgroupPath), nil
+	} else {
+		return "", fmt.Errorf("cgroup path error %v", err)
+	}
+}

cgroups/subsystems/utils_test.go

@@ -0,0 +1,11 @@
+package subsystems
+
+import(
+	"testing"
+)
+
+func TestFindCgroupMountpoint(t *testing.T) {
+	t.Logf("cpu subsystem mount point %v\n", FindCgroupMountpoint("cpu"))
+	t.Logf("cpuset subsystem mount point %v\n", FindCgroupMountpoint("cpuset"))
+	t.Logf("memory subsystem mount point %v\n", FindCgroupMountpoint("memory"))
+}

container/container_process.go

@@ -1,22 +1,37 @@
 package container
 
 import (
-	"syscall"
-	"os/exec"
+	log "github.com/Sirupsen/logrus"
 	"os"
+	"os/exec"
+	"syscall"
 )
 
-func NewParentProcess(tty bool, command string) *exec.Cmd {
-	args := []string{"init", command}
-	cmd := exec.Command("/proc/self/exe", args...)
-    cmd.SysProcAttr = &syscall.SysProcAttr{
-        Cloneflags: syscall.CLONE_NEWUTS | syscall.CLONE_NEWPID | syscall.CLONE_NEWNS |
-		syscall.CLONE_NEWNET | syscall.CLONE_NEWIPC,
-    }
+func NewParentProcess(tty bool) (*exec.Cmd, *os.File) {
+	readPipe, writePipe, err := NewPipe()
+	if err != nil {
+		log.Errorf("New pipe error %v", err)
+		return nil, nil
+	}
+	cmd := exec.Command("/proc/self/exe", "init")
+	cmd.SysProcAttr = &syscall.SysProcAttr{
+		Cloneflags: syscall.CLONE_NEWUTS | syscall.CLONE_NEWPID | syscall.CLONE_NEWNS |
+			syscall.CLONE_NEWNET | syscall.CLONE_NEWIPC,
+	}
 	if tty {
 		cmd.Stdin = os.Stdin
 		cmd.Stdout = os.Stdout
 		cmd.Stderr = os.Stderr
 	}
-	return cmd
+	cmd.ExtraFiles = []*os.File{readPipe}
+	cmd.Dir = "/root/busybox"
+	return cmd, writePipe
+}
+
+func NewPipe() (*os.File, *os.File, error) {
+	read, write, err := os.Pipe()
+	if err != nil {
+		return nil, nil, err
+	}
+	return read, write, nil
 }