diff options
| -rw-r--r-- | pkg/tcpip/network/ipv4/ipv4.go | 12 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv6/ipv6.go | 12 | ||||
| -rw-r--r-- | pkg/tcpip/stack/addressable_endpoint_state.go | 52 |
3 files changed, 49 insertions, 27 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) } diff --git a/pkg/tcpip/stack/addressable_endpoint_state.go b/pkg/tcpip/stack/addressable_endpoint_state.go index e5590ecc0..ce9cebdaa 100644 --- a/pkg/tcpip/stack/addressable_endpoint_state.go +++ b/pkg/tcpip/stack/addressable_endpoint_state.go @@ -440,33 +440,54 @@ func (a *AddressableEndpointState) acquirePrimaryAddressRLocked(isValid func(*ad // Regardless how the address was obtained, it will be acquired before it is // returned. func (a *AddressableEndpointState) AcquireAssignedAddressOrMatching(localAddr tcpip.Address, f func(AddressEndpoint) bool, allowTemp bool, tempPEB PrimaryEndpointBehavior) AddressEndpoint { - a.mu.Lock() - defer a.mu.Unlock() + lookup := func() *addressState { + if addrState, ok := a.mu.endpoints[localAddr]; ok { + if !addrState.IsAssigned(allowTemp) { + return nil + } - if addrState, ok := a.mu.endpoints[localAddr]; ok { - if !addrState.IsAssigned(allowTemp) { - return nil - } + if !addrState.IncRef() { + panic(fmt.Sprintf("failed to increase the reference count for address = %s", addrState.addr)) + } - if !addrState.IncRef() { - panic(fmt.Sprintf("failed to increase the reference count for address = %s", addrState.addr)) + return addrState } - return addrState - } - - if f != nil { - for _, addrState := range a.mu.endpoints { - if addrState.IsAssigned(allowTemp) && f(addrState) && addrState.IncRef() { - return addrState + if f != nil { + for _, addrState := range a.mu.endpoints { + if addrState.IsAssigned(allowTemp) && f(addrState) && addrState.IncRef() { + return addrState + } } } + return nil + } + // Avoid exclusive lock on mu unless we need to add a new address. + a.mu.RLock() + ep := lookup() + a.mu.RUnlock() + + if ep != nil { + return ep } if !allowTemp { return nil } + // Acquire state lock in exclusive mode as we need to add a new temporary + // endpoint. + a.mu.Lock() + defer a.mu.Unlock() + + // Do the lookup again in case another goroutine added the address in the time + // we released and acquired the lock. + ep = lookup() + if ep != nil { + return ep + } + + // Proceed to add a new temporary endpoint. addr := localAddr.WithPrefix() ep, err := a.addAndAcquireAddressLocked(addr, tempPEB, AddressConfigStatic, false /* deprecated */, false /* permanent */) if err != nil { @@ -475,6 +496,7 @@ func (a *AddressableEndpointState) AcquireAssignedAddressOrMatching(localAddr tc // expect no error. panic(fmt.Sprintf("a.addAndAcquireAddressLocked(%s, %d, %d, false, false): %s", addr, tempPEB, AddressConfigStatic, err)) } + // From https://golang.org/doc/faq#nil_error: // // Under the covers, interfaces are implemented as two elements, a type T and |