health: add Tracker type, in prep for removing global variables

This moves most of the health package global variables to a new
`health.Tracker` type.

But then rather than plumbing the Tracker in tsd.System everywhere,
this only goes halfway and makes one new global Tracker
(`health.Global`) that all the existing callers now use.

A future change will eliminate that global.

Updates #11874
Updates #4136

Change-Id: I6ee27e0b2e35f68cb38fecdb3b2dc4c3f2e09d68
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

wgengine/magicsock/derp.go

@@ -165,7 +165,7 @@ func (c *Conn) maybeSetNearestDERP(report *netcheck.Report) (preferredDERP int)
 	if testenv.InTest() && !checkControlHealthDuringNearestDERPInTests {
 		connectedToControl = true
 	} else {
-		connectedToControl = health.GetInPollNetMap()
+		connectedToControl = health.Global.GetInPollNetMap()
 	}
 	if !connectedToControl {
 		c.mu.Lock()
@@ -201,12 +201,12 @@ func (c *Conn) setNearestDERP(derpNum int) (wantDERP bool) {
 	defer c.mu.Unlock()
 	if !c.wantDerpLocked() {
 		c.myDerp = 0
-		health.SetMagicSockDERPHome(0, c.homeless)
+		health.Global.SetMagicSockDERPHome(0, c.homeless)
 		return false
 	}
 	if c.homeless {
 		c.myDerp = 0
-		health.SetMagicSockDERPHome(0, c.homeless)
+		health.Global.SetMagicSockDERPHome(0, c.homeless)
 		return false
 	}
 	if derpNum == c.myDerp {
@@ -217,7 +217,7 @@ func (c *Conn) setNearestDERP(derpNum int) (wantDERP bool) {
 		metricDERPHomeChange.Add(1)
 	}
 	c.myDerp = derpNum
-	health.SetMagicSockDERPHome(derpNum, c.homeless)
+	health.Global.SetMagicSockDERPHome(derpNum, c.homeless)
 
 	if c.privateKey.IsZero() {
 		// No private key yet, so DERP connections won't come up anyway.
@@ -525,8 +525,8 @@ func (c *Conn) runDerpReader(ctx context.Context, derpFakeAddr netip.AddrPort, d
 		return n
 	}
 
-	defer health.SetDERPRegionConnectedState(regionID, false)
-	defer health.SetDERPRegionHealth(regionID, "")
+	defer health.Global.SetDERPRegionConnectedState(regionID, false)
+	defer health.Global.SetDERPRegionHealth(regionID, "")
 
 	// peerPresent is the set of senders we know are present on this
 	// connection, based on messages we've received from the server.
@@ -538,7 +538,7 @@ func (c *Conn) runDerpReader(ctx context.Context, derpFakeAddr netip.AddrPort, d
 	for {
 		msg, connGen, err := dc.RecvDetail()
 		if err != nil {
-			health.SetDERPRegionConnectedState(regionID, false)
+			health.Global.SetDERPRegionConnectedState(regionID, false)
 			// Forget that all these peers have routes.
 			for peer := range peerPresent {
 				delete(peerPresent, peer)
@@ -576,14 +576,14 @@ func (c *Conn) runDerpReader(ctx context.Context, derpFakeAddr netip.AddrPort, d
 
 		now := time.Now()
 		if lastPacketTime.IsZero() || now.Sub(lastPacketTime) > frameReceiveRecordRate {
-			health.NoteDERPRegionReceivedFrame(regionID)
+			health.Global.NoteDERPRegionReceivedFrame(regionID)
 			lastPacketTime = now
 		}
 
 		switch m := msg.(type) {
 		case derp.ServerInfoMessage:
-			health.SetDERPRegionConnectedState(regionID, true)
-			health.SetDERPRegionHealth(regionID, "") // until declared otherwise
+			health.Global.SetDERPRegionConnectedState(regionID, true)
+			health.Global.SetDERPRegionHealth(regionID, "") // until declared otherwise
 			c.logf("magicsock: derp-%d connected; connGen=%v", regionID, connGen)
 			continue
 		case derp.ReceivedPacket:
@@ -623,7 +623,7 @@ func (c *Conn) runDerpReader(ctx context.Context, derpFakeAddr netip.AddrPort, d
 			}()
 			continue
 		case derp.HealthMessage:
-			health.SetDERPRegionHealth(regionID, m.Problem)
+			health.Global.SetDERPRegionHealth(regionID, m.Problem)
 			continue
 		case derp.PeerGoneMessage:
 			switch m.Reason {

wgengine/magicsock/magicsock.go

@@ -666,7 +666,7 @@ func (c *Conn) updateNetInfo(ctx context.Context) (*netcheck.Report, error) {
 		// NOTE(andrew-d): I don't love that we're depending on the
 		// health package here, but I'd rather do that and not store
 		// the exact same state in two different places.
-		GetLastDERPActivity: health.GetDERPRegionReceivedTime,
+		GetLastDERPActivity: health.Global.GetDERPRegionReceivedTime,
 	})
 	if err != nil {
 		return nil, err
@@ -2471,7 +2471,7 @@ func (c *Conn) bindSocket(ruc *RebindingUDPConn, network string, curPortFate cur
 		}
 		ruc.setConnLocked(pconn, network, c.bind.BatchSize())
 		if network == "udp4" {
-			health.SetUDP4Unbound(false)
+			health.Global.SetUDP4Unbound(false)
 		}
 		return nil
 	}
@@ -2482,7 +2482,7 @@ func (c *Conn) bindSocket(ruc *RebindingUDPConn, network string, curPortFate cur
 	// we get a link change and we can try binding again.
 	ruc.setConnLocked(newBlockForeverConn(), "", c.bind.BatchSize())
 	if network == "udp4" {
-		health.SetUDP4Unbound(true)
+		health.Global.SetUDP4Unbound(true)
 	}
 	return fmt.Errorf("failed to bind any ports (tried %v)", ports)
 }

wgengine/magicsock/magicsock_test.go

@@ -3120,14 +3120,14 @@ func TestMaybeSetNearestDERP(t *testing.T) {
 
 			report := &netcheck.Report{PreferredDERP: tt.reportDERP}
 
-			oldConnected := health.GetInPollNetMap()
+			oldConnected := health.Global.GetInPollNetMap()
 			if tt.connectedToControl != oldConnected {
 				if tt.connectedToControl {
-					health.GotStreamedMapResponse()
-					t.Cleanup(health.SetOutOfPollNetMap)
+					health.Global.GotStreamedMapResponse()
+					t.Cleanup(health.Global.SetOutOfPollNetMap)
 				} else {
-					health.SetOutOfPollNetMap()
-					t.Cleanup(health.GotStreamedMapResponse)
+					health.Global.SetOutOfPollNetMap()
+					t.Cleanup(health.Global.GotStreamedMapResponse)
 				}
 			}
 

wgengine/router/ifconfig_windows.go

@@ -235,7 +235,7 @@ func interfaceFromLUID(luid winipcfg.LUID, flags winipcfg.GAAFlags) (*winipcfg.I
 	return nil, fmt.Errorf("interfaceFromLUID: interface with LUID %v not found", luid)
 }
 
-var networkCategoryWarning = health.NewWarnable(health.WithMapDebugFlag("warn-network-category-unhealthy"))
+var networkCategoryWarning = health.Global.NewWarnable(health.WithMapDebugFlag("warn-network-category-unhealthy"))
 
 func configureInterface(cfg *Config, tun *tun.NativeTun) (retErr error) {
 	var mtu = tstun.DefaultTUNMTU()

wgengine/userspace.go

@@ -970,7 +970,7 @@ func (e *userspaceEngine) Reconfig(cfg *wgcfg.Config, routerCfg *router.Config,
 		e.logf("wgengine: Reconfig: configuring router")
 		e.networkLogger.ReconfigRoutes(routerCfg)
 		err := e.router.Set(routerCfg)
-		health.SetRouterHealth(err)
+		health.Global.SetRouterHealth(err)
 		if err != nil {
 			return err
 		}
@@ -979,7 +979,7 @@ func (e *userspaceEngine) Reconfig(cfg *wgcfg.Config, routerCfg *router.Config,
 		// assigned address.
 		e.logf("wgengine: Reconfig: configuring DNS")
 		err = e.dns.Set(*dnsCfg)
-		health.SetDNSHealth(err)
+		health.Global.SetDNSHealth(err)
 		if err != nil {
 			return err
 		}
@@ -1183,7 +1183,7 @@ func (e *userspaceEngine) linkChange(delta *netmon.ChangeDelta) {
 		e.logf("[v1] LinkChange: minor")
 	}
 
-	health.SetAnyInterfaceUp(up)
+	health.Global.SetAnyInterfaceUp(up)
 	e.magicConn.SetNetworkUp(up)
 	if !up || changed {
 		if err := e.dns.FlushCaches(); err != nil {