Revert "Adjust LockOSThread"

This reverts commit 94af1e5af201a87c651ef1a531bb19efdcd413e0.

The reason to revert this is, that TestCreateParallel is
continously failing and breaking the CI

Signed-off-by: Arko Dasgupta <arko.dasgupta@docker.com>

libnetwork/libnetwork_linux_test.go

@@ -850,7 +850,6 @@ func parallelJoin(t *testing.T, rc libnetwork.Sandbox, ep libnetwork.Endpoint, t
 	err = ep.Join(sb)
 
 	runtime.LockOSThread()
-	defer runtime.UnlockOSThread()
 	if err != nil {
 		if _, ok := err.(types.ForbiddenError); !ok {
 			t.Fatalf("thread %d: %v", thrNumber, err)
@@ -868,7 +867,6 @@ func parallelLeave(t *testing.T, rc libnetwork.Sandbox, ep libnetwork.Endpoint,
 
 	err = ep.Leave(sb)
 	runtime.LockOSThread()
-	defer runtime.UnlockOSThread()
 	if err != nil {
 		if _, ok := err.(types.ForbiddenError); !ok {
 			t.Fatalf("thread %d: %v", thrNumber, err)

libnetwork/ns/init_linux.go

@@ -39,6 +39,19 @@ func Init() {
 	}
 }
 
+// SetNamespace sets the initial namespace handler
+func SetNamespace() error {
+	initOnce.Do(Init)
+	if err := netns.Set(initNs); err != nil {
+		linkInfo, linkErr := getLink()
+		if linkErr != nil {
+			linkInfo = linkErr.Error()
+		}
+		return fmt.Errorf("failed to set to initial namespace, %v, initns fd %d: %v", linkInfo, initNs, err)
+	}
+	return nil
+}
+
 // ParseHandlerInt transforms the namespace handler into an integer
 func ParseHandlerInt() int {
 	return int(getHandler())

libnetwork/osl/namespace_linux.go

@@ -424,10 +424,13 @@ func (n *networkNamespace) InvokeFunc(f func()) error {
 // InitOSContext initializes OS context while configuring network resources
 func InitOSContext() func() {
 	runtime.LockOSThread()
+	if err := ns.SetNamespace(); err != nil {
+		logrus.Error(err)
+	}
 	return runtime.UnlockOSThread
 }
 
-func nsInvoke(path string, prefunc, postfunc func(int) error) error {
+func nsInvoke(path string, prefunc func(nsFD int) error, postfunc func(callerFD int) error) error {
 	defer InitOSContext()()
 
 	newNs, err := netns.GetFromPath(path)
@@ -442,17 +445,10 @@ func nsInvoke(path string, prefunc, postfunc func(int) error) error {
 		return fmt.Errorf("failed in prefunc: %v", err)
 	}
 
-	// save the current namespace (host namespace)
-	curNs, err := netns.Get()
-	if err != nil {
-		return err
-	}
-	defer curNs.Close()
 	if err = netns.Set(newNs); err != nil {
 		return err
 	}
-	// will restore the previous namespace before unlocking the thread
-	defer netns.Set(curNs)
+	defer ns.SetNamespace()
 
 	// Invoked after the namespace switch.
 	return postfunc(ns.ParseHandlerInt())

libnetwork/osl/sandbox_linux_test.go

@@ -7,6 +7,7 @@ import (
 	"net"
 	"os"
 	"path/filepath"
+	"runtime"
 	"strings"
 	"syscall"
 	"testing"
@@ -198,6 +199,7 @@ func TestDisableIPv6DAD(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Failed to create a new sandbox: %v", err)
 	}
+	runtime.LockOSThread()
 	defer s.Destroy()
 
 	n, ok := s.(*networkNamespace)
@@ -251,6 +253,7 @@ func TestSetInterfaceIP(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Failed to create a new sandbox: %v", err)
 	}
+	runtime.LockOSThread()
 	defer s.Destroy()
 
 	n, ok := s.(*networkNamespace)
@@ -326,6 +329,7 @@ func TestLiveRestore(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Failed to create a new sandbox: %v", err)
 	}
+	runtime.LockOSThread()
 	defer s.Destroy()
 
 	n, ok := s.(*networkNamespace)

libnetwork/osl/sandbox_test.go

@@ -2,6 +2,7 @@ package osl
 
 import (
 	"os"
+	"runtime"
 	"testing"
 
 	"github.com/docker/docker/pkg/reexec"
@@ -79,6 +80,7 @@ func TestSandboxCreateTwice(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Failed to create a new sandbox: %v", err)
 	}
+	runtime.LockOSThread()
 
 	// Create another sandbox with the same key to see if we handle it
 	// gracefully.
@@ -86,6 +88,7 @@ func TestSandboxCreateTwice(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Failed to create a new sandbox: %v", err)
 	}
+	runtime.LockOSThread()
 
 	err = s.Destroy()
 	if err != nil {
@@ -127,6 +130,7 @@ func TestAddRemoveInterface(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Failed to create a new sandbox: %v", err)
 	}
+	runtime.LockOSThread()
 
 	if s.Key() != key {
 		t.Fatalf("s.Key() returned %s. Expected %s", s.Key(), key)

libnetwork/testutils/context_unix.go

@@ -33,6 +33,8 @@ func SetupTestOSContext(t *testing.T) func() {
 	// sure to re-initialize initNs context
 	ns.Init()
 
+	runtime.LockOSThread()
+
 	return func() {
 		if err := syscall.Close(fd); err != nil {
 			t.Logf("Warning: netns closing failed (%v)", err)