Change AcquireAssignedAddress to use RLock.

This is a hot path for all incoming packets and we don't
need an exclusive lock here as we are not modifying any
of the fields protected by mu here.

PiperOrigin-RevId: 373181254

2 files changed, 12 insertions, 12 deletions

diff --git a/pkg/tcpip/network/ipv4/ipv4.go b/pkg/tcpip/network/ipv4/ipv4.go
index 19657fde1..4031032d0 100644
--- a/pkg/tcpip/network/ipv4/ipv4.go
+++ b/pkg/tcpip/network/ipv4/ipv4.go
@@ -990,8 +990,8 @@ func (e *endpoint) Close() {
 
 // AddAndAcquirePermanentAddress implements stack.AddressableEndpoint.
 func (e *endpoint) AddAndAcquirePermanentAddress(addr tcpip.AddressWithPrefix, peb stack.PrimaryEndpointBehavior, configType stack.AddressConfigType, deprecated bool) (stack.AddressEndpoint, tcpip.Error) {
-	e.mu.Lock()
-	defer e.mu.Unlock()
+	e.mu.RLock()
+	defer e.mu.RUnlock()
 
 	ep, err := e.mu.addressableEndpointState.AddAndAcquirePermanentAddress(addr, peb, configType, deprecated)
 	if err == nil {
@@ -1002,8 +1002,8 @@ func (e *endpoint) AddAndAcquirePermanentAddress(addr tcpip.AddressWithPrefix, p
 
 // RemovePermanentAddress implements stack.AddressableEndpoint.
 func (e *endpoint) RemovePermanentAddress(addr tcpip.Address) tcpip.Error {
-	e.mu.Lock()
-	defer e.mu.Unlock()
+	e.mu.RLock()
+	defer e.mu.RUnlock()
 	return e.mu.addressableEndpointState.RemovePermanentAddress(addr)
 }
 
@@ -1016,8 +1016,8 @@ func (e *endpoint) MainAddress() tcpip.AddressWithPrefix {
 
 // AcquireAssignedAddress implements stack.AddressableEndpoint.
 func (e *endpoint) AcquireAssignedAddress(localAddr tcpip.Address, allowTemp bool, tempPEB stack.PrimaryEndpointBehavior) stack.AddressEndpoint {
-	e.mu.Lock()
-	defer e.mu.Unlock()
+	e.mu.RLock()
+	defer e.mu.RUnlock()
 
 	loopback := e.nic.IsLoopback()
 	return e.mu.addressableEndpointState.AcquireAssignedAddressOrMatching(localAddr, func(addressEndpoint stack.AddressEndpoint) bool {
diff --git a/pkg/tcpip/network/ipv6/ipv6.go b/pkg/tcpip/network/ipv6/ipv6.go
index 4fdb2793d..029d5f51b 100644
--- a/pkg/tcpip/network/ipv6/ipv6.go
+++ b/pkg/tcpip/network/ipv6/ipv6.go
@@ -1546,8 +1546,8 @@ func (e *endpoint) NetworkProtocolNumber() tcpip.NetworkProtocolNumber {
 func (e *endpoint) AddAndAcquirePermanentAddress(addr tcpip.AddressWithPrefix, peb stack.PrimaryEndpointBehavior, configType stack.AddressConfigType, deprecated bool) (stack.AddressEndpoint, tcpip.Error) {
 	// TODO(b/169350103): add checks here after making sure we no longer receive
 	// an empty address.
-	e.mu.Lock()
-	defer e.mu.Unlock()
+	e.mu.RLock()
+	defer e.mu.RUnlock()
 	return e.addAndAcquirePermanentAddressLocked(addr, peb, configType, deprecated)
 }
 
@@ -1588,8 +1588,8 @@ func (e *endpoint) addAndAcquirePermanentAddressLocked(addr tcpip.AddressWithPre
 
 // RemovePermanentAddress implements stack.AddressableEndpoint.
 func (e *endpoint) RemovePermanentAddress(addr tcpip.Address) tcpip.Error {
-	e.mu.Lock()
-	defer e.mu.Unlock()
+	e.mu.RLock()
+	defer e.mu.RUnlock()
 
 	addressEndpoint := e.getAddressRLocked(addr)
 	if addressEndpoint == nil || !addressEndpoint.GetKind().IsPermanent() {
@@ -1666,8 +1666,8 @@ func (e *endpoint) MainAddress() tcpip.AddressWithPrefix {
 
 // AcquireAssignedAddress implements stack.AddressableEndpoint.
 func (e *endpoint) AcquireAssignedAddress(localAddr tcpip.Address, allowTemp bool, tempPEB stack.PrimaryEndpointBehavior) stack.AddressEndpoint {
-	e.mu.Lock()
-	defer e.mu.Unlock()
+	e.mu.RLock()
+	defer e.mu.RUnlock()
 	return e.acquireAddressOrCreateTempLocked(localAddr, allowTemp, tempPEB)
 }