Merge pull request #2243 from fcrisciani/syscalls

Syscalls reduction

libnetwork/libnetwork_linux_test.go

@@ -850,6 +850,7 @@ 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)
@@ -867,6 +868,7 @@ 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

@@ -39,19 +39,6 @@ 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

@@ -424,13 +424,10 @@ 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 func(nsFD int) error, postfunc func(callerFD int) error) error {
+func nsInvoke(path string, prefunc, postfunc func(int) error) error {
 	defer InitOSContext()()
 
 	newNs, err := netns.GetFromPath(path)
@@ -445,10 +442,17 @@ func nsInvoke(path string, prefunc func(nsFD int) error, postfunc func(callerFD
 		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
 	}
-	defer ns.SetNamespace()
+	// will restore the previous namespace before unlocking the thread
+	defer netns.Set(curNs)
 
 	// Invoked after the namespace switch.
 	return postfunc(ns.ParseHandlerInt())
@@ -681,7 +685,7 @@ func (n *networkNamespace) ApplyOSTweaks(types []SandboxType) {
 	for _, t := range types {
 		switch t {
 		case SandboxTypeLoadBalancer:
-			kernel.ApplyOSTweaks(loadBalancerConfig)
+			n.InvokeFunc(func() { kernel.ApplyOSTweaks(loadBalancerConfig) })
 		}
 	}
 }

libnetwork/osl/sandbox_linux_test.go

@@ -7,7 +7,6 @@ import (
 	"net"
 	"os"
 	"path/filepath"
-	"runtime"
 	"strings"
 	"syscall"
 	"testing"
@@ -199,7 +198,6 @@ 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)
@@ -253,7 +251,6 @@ 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)
@@ -329,7 +326,6 @@ 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

@@ -2,7 +2,6 @@ package osl
 
 import (
 	"os"
-	"runtime"
 	"testing"
 
 	"github.com/docker/docker/pkg/reexec"
@@ -80,7 +79,6 @@ 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.
@@ -88,7 +86,6 @@ 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 {
@@ -130,7 +127,6 @@ 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

@@ -33,8 +33,6 @@ 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)