diff --git a/cmd/tailscaled/depaware.txt b/cmd/tailscaled/depaware.txt index 4ef52a4e4..515ed200c 100644 --- a/cmd/tailscaled/depaware.txt +++ b/cmd/tailscaled/depaware.txt @@ -292,6 +292,7 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de tailscale.com/util/osshare from tailscale.com/ipn/ipnlocal+ tailscale.com/util/pidowner from tailscale.com/ipn/ipnauth tailscale.com/util/racebuild from tailscale.com/logpolicy + tailscale.com/util/set from tailscale.com/health+ tailscale.com/util/singleflight from tailscale.com/control/controlclient+ tailscale.com/util/strs from tailscale.com/hostinfo+ tailscale.com/util/systemd from tailscale.com/control/controlclient+ diff --git a/health/health.go b/health/health.go index c8b7831b3..a08c6100d 100644 --- a/health/health.go +++ b/health/health.go @@ -19,15 +19,16 @@ "tailscale.com/envknob" "tailscale.com/tailcfg" "tailscale.com/util/multierr" + "tailscale.com/util/set" ) var ( // mu guards everything in this var block. mu sync.Mutex - sysErr = map[Subsystem]error{} // error key => err (or nil for no error) - watchers = map[*watchHandle]func(Subsystem, error){} // opt func to run if error state changes - warnables = map[*Warnable]struct{}{} // set of warnables + sysErr = map[Subsystem]error{} // error key => err (or nil for no error) + watchers = set.HandleSet[func(Subsystem, error)]{} // opt func to run if error state changes + warnables = map[*Warnable]struct{}{} // set of warnables timer *time.Timer debugHandler = map[string]http.Handler{} @@ -148,8 +149,6 @@ func AppendWarnableDebugFlags(base []string) []string { return ret } -type watchHandle byte - // RegisterWatcher adds a function that will be called if an // error changes state either to unhealthy or from unhealthy. It is // not called on transition from unknown to healthy. It must be non-nil @@ -157,8 +156,7 @@ func AppendWarnableDebugFlags(base []string) []string { func RegisterWatcher(cb func(key Subsystem, err error)) (unregister func()) { mu.Lock() defer mu.Unlock() - handle := new(watchHandle) - watchers[handle] = cb + handle := watchers.Add(cb) if timer == nil { timer = time.AfterFunc(time.Minute, timerSelfCheck) } @@ -174,23 +172,23 @@ func RegisterWatcher(cb func(key Subsystem, err error)) (unregister func()) { } // SetRouterHealth sets the state of the wgengine/router.Router. -func SetRouterHealth(err error) { set(SysRouter, err) } +func SetRouterHealth(err error) { setErr(SysRouter, err) } // RouterHealth returns the wgengine/router.Router error state. func RouterHealth() error { return get(SysRouter) } // SetDNSHealth sets the state of the net/dns.Manager -func SetDNSHealth(err error) { set(SysDNS, err) } +func SetDNSHealth(err error) { setErr(SysDNS, err) } // DNSHealth returns the net/dns.Manager error state. func DNSHealth() error { return get(SysDNS) } // SetDNSOSHealth sets the state of the net/dns.OSConfigurator -func SetDNSOSHealth(err error) { set(SysDNSOS, err) } +func SetDNSOSHealth(err error) { setErr(SysDNSOS, err) } // SetDNSManagerHealth sets the state of the Linux net/dns manager's // discovery of the /etc/resolv.conf situation. -func SetDNSManagerHealth(err error) { set(SysDNSManager, err) } +func SetDNSManagerHealth(err error) { setErr(SysDNSManager, err) } // DNSOSHealth returns the net/dns.OSConfigurator error state. func DNSOSHealth() error { return get(SysDNSOS) } @@ -213,7 +211,7 @@ func get(key Subsystem) error { return sysErr[key] } -func set(key Subsystem, err error) { +func setErr(key Subsystem, err error) { mu.Lock() defer mu.Unlock() setLocked(key, err) diff --git a/ipn/ipnlocal/local.go b/ipn/ipnlocal/local.go index be8b645b0..021d321d5 100644 --- a/ipn/ipnlocal/local.go +++ b/ipn/ipnlocal/local.go @@ -65,6 +65,7 @@ "tailscale.com/util/mak" "tailscale.com/util/multierr" "tailscale.com/util/osshare" + "tailscale.com/util/set" "tailscale.com/util/systemd" "tailscale.com/util/uniq" "tailscale.com/version" @@ -180,8 +181,8 @@ type LocalBackend struct { peerAPIListeners []*peerAPIListener loginFlags controlclient.LoginFlags incomingFiles map[*incomingFile]bool - fileWaiters map[*mapSetHandle]context.CancelFunc // handle => func to call on file received - notifyWatchers map[*mapSetHandle]chan *ipn.Notify + fileWaiters set.HandleSet[context.CancelFunc] // of wake-up funcs + notifyWatchers set.HandleSet[chan *ipn.Notify] lastStatusTime time.Time // status.AsOf value of the last processed status update // directFileRoot, if non-empty, means to write received files // directly to this directory, without staging them in an @@ -1703,11 +1704,10 @@ func (b *LocalBackend) readPoller() { // notifications. There is currently (2022-11-22) no mechanism provided to // detect when a message has been dropped. func (b *LocalBackend) WatchNotifications(ctx context.Context, mask ipn.NotifyWatchOpt, fn func(roNotify *ipn.Notify) (keepGoing bool)) { - handle := new(mapSetHandle) ch := make(chan *ipn.Notify, 128) b.mu.Lock() - mak.Set(&b.notifyWatchers, handle, ch) + handle := b.notifyWatchers.Add(ch) b.mu.Unlock() defer func() { b.mu.Lock() @@ -3745,18 +3745,16 @@ func (b *LocalBackend) TestOnlyPublicKeys() (machineKey key.MachinePublic, nodeK return mk, nk } -// mapSetHandle is a minimal (but non-zero) value whose address serves as a map -// key for sets of non-comparable values that can't be map keys themselves. -type mapSetHandle byte - -func (b *LocalBackend) setFileWaiter(handle *mapSetHandle, wakeWaiter context.CancelFunc) { +func (b *LocalBackend) removeFileWaiter(handle set.Handle) { b.mu.Lock() defer b.mu.Unlock() - if wakeWaiter == nil { - delete(b.fileWaiters, handle) - } else { - mak.Set(&b.fileWaiters, handle, wakeWaiter) - } + delete(b.fileWaiters, handle) +} + +func (b *LocalBackend) addFileWaiter(wakeWaiter context.CancelFunc) set.Handle { + b.mu.Lock() + defer b.mu.Unlock() + return b.fileWaiters.Add(wakeWaiter) } func (b *LocalBackend) WaitingFiles() ([]apitype.WaitingFile, error) { @@ -3780,9 +3778,8 @@ func (b *LocalBackend) AwaitWaitingFiles(ctx context.Context) ([]apitype.Waiting gotFile, gotFileCancel := context.WithCancel(context.Background()) defer gotFileCancel() - handle := new(mapSetHandle) - b.setFileWaiter(handle, gotFileCancel) - defer b.setFileWaiter(handle, nil) + handle := b.addFileWaiter(gotFileCancel) + defer b.removeFileWaiter(handle) // Now that we've registered ourselves, check again, in case // of race. Otherwise there's a small window where we could diff --git a/util/set/set.go b/util/set/set.go new file mode 100644 index 000000000..cf2a81953 --- /dev/null +++ b/util/set/set.go @@ -0,0 +1,30 @@ +// Copyright (c) 2022 Tailscale Inc & AUTHORS All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package set contains set types. +package set + +// HandleSet is a set of T. +// +// It is not safe for concurrent use. +type HandleSet[T any] map[Handle]T + +// Handle is a opaque comparable value that's used as the map key +// in a HandleSet. The only way to get one is to call HandleSet.Add. +type Handle struct { + v *byte +} + +// Add adds the element (map value) e to the set. +// +// It returns the handle (map key) with which e can be removed, using a map +// delete. +func (s *HandleSet[T]) Add(e T) Handle { + h := Handle{new(byte)} + if *s == nil { + *s = make(HandleSet[T]) + } + (*s)[h] = e + return h +} diff --git a/wgengine/monitor/monitor.go b/wgengine/monitor/monitor.go index ba099196d..84d6db5e6 100644 --- a/wgengine/monitor/monitor.go +++ b/wgengine/monitor/monitor.go @@ -17,6 +17,7 @@ "tailscale.com/net/interfaces" "tailscale.com/types/logger" + "tailscale.com/util/set" ) // pollWallTimeInterval is how often we check the time to check @@ -54,9 +55,6 @@ type osMon interface { // callback. type ChangeFunc func(changed bool, state *interfaces.State) -// An allocated callbackHandle's address is the Mon.cbs map key. -type callbackHandle byte - // Mon represents a monitoring instance. type Mon struct { logf logger.Logf @@ -65,8 +63,8 @@ type Mon struct { stop chan struct{} // closed on Stop mu sync.Mutex // guards all following fields - cbs map[*callbackHandle]ChangeFunc - ruleDelCB map[*callbackHandle]RuleDeleteCallback + cbs set.HandleSet[ChangeFunc] + ruleDelCB set.HandleSet[RuleDeleteCallback] ifState *interfaces.State gwValid bool // whether gw and gwSelfIP are valid gw netip.Addr // our gateway's IP @@ -86,7 +84,6 @@ func New(logf logger.Logf) (*Mon, error) { logf = logger.WithPrefix(logf, "monitor: ") m := &Mon{ logf: logf, - cbs: map[*callbackHandle]ChangeFunc{}, change: make(chan struct{}, 1), stop: make(chan struct{}), lastWall: wallTime(), @@ -144,10 +141,9 @@ func (m *Mon) GatewayAndSelfIP() (gw, myIP netip.Addr, ok bool) { // notified (in their own goroutine) when the network state changes. // To remove this callback, call unregister (or close the monitor). func (m *Mon) RegisterChangeCallback(callback ChangeFunc) (unregister func()) { - handle := new(callbackHandle) m.mu.Lock() defer m.mu.Unlock() - m.cbs[handle] = callback + handle := m.cbs.Add(callback) return func() { m.mu.Lock() defer m.mu.Unlock() @@ -165,13 +161,9 @@ func (m *Mon) RegisterChangeCallback(callback ChangeFunc) (unregister func()) { // notified (in their own goroutine) when a Linux ip rule is deleted. // To remove this callback, call unregister (or close the monitor). func (m *Mon) RegisterRuleDeleteCallback(callback RuleDeleteCallback) (unregister func()) { - handle := new(callbackHandle) m.mu.Lock() defer m.mu.Unlock() - if m.ruleDelCB == nil { - m.ruleDelCB = map[*callbackHandle]RuleDeleteCallback{} - } - m.ruleDelCB[handle] = callback + handle := m.ruleDelCB.Add(callback) return func() { m.mu.Lock() defer m.mu.Unlock()