kv, gossip: remove misc deprecated system config code

There is still some work left to actually remove `SystemConfigSpan`
or at least update `SystemConfigSpan` to contain just system.descriptor and
system.zones.

cockroachdb#76279

Release note: None

pkg/gossip/gossip.go

@@ -1145,37 +1145,6 @@ func (g *Gossip) RegisterCallback(pattern string, method Callback, opts ...Callb
 	}
 }
 
-// DeprecatedGetSystemConfig returns the local unmarshaled version of the system config.
-// Returns nil if the system config hasn't been set yet.
-//
-// TODO(ajwerner): Remove this in 22.2.
-func (g *Gossip) DeprecatedGetSystemConfig() *config.SystemConfig {
-	g.systemConfigMu.RLock()
-	defer g.systemConfigMu.RUnlock()
-	return g.systemConfig
-}
-
-// DeprecatedRegisterSystemConfigChannel registers a channel to signify updates for the
-// system config. It is notified after registration (if a system config is
-// already set), and whenever a new system config is successfully unmarshaled.
-//
-// TODO(ajwerner): Remove this in 22.2.
-func (g *Gossip) DeprecatedRegisterSystemConfigChannel() <-chan struct{} {
-	// Create channel that receives new system config notifications.
-	// The channel has a size of 1 to prevent gossip from having to block on it.
-	c := make(chan struct{}, 1)
-
-	g.systemConfigMu.Lock()
-	defer g.systemConfigMu.Unlock()
-	g.systemConfigChannels = append(g.systemConfigChannels, c)
-
-	// Notify the channel right away if we have a config.
-	if g.systemConfig != nil {
-		c <- struct{}{}
-	}
-	return c
-}
-
 // updateSystemConfig is the raw gossip info callback. Unmarshal the
 // system config, and if successful, send on each system config
 // channel.

pkg/kv/kvclient/kvcoord/txn_coord_sender.go

@@ -11,12 +11,10 @@
 package kvcoord
 
 import (
-	"bytes"
 	"context"
 	"fmt"
 	"runtime/debug"
 
-	"github.com/cockroachdb/cockroach/pkg/keys"
 	"github.com/cockroachdb/cockroach/pkg/kv"
 	"github.com/cockroachdb/cockroach/pkg/roachpb"
 	"github.com/cockroachdb/cockroach/pkg/storage/enginepb"
@@ -994,20 +992,6 @@ func (tc *TxnCoordSender) setTxnAnchorKeyLocked(key roachpb.Key) error {
 	return nil
 }
 
-// AnchorOnSystemConfigRange is part of the client.TxnSender interface.
-func (tc *TxnCoordSender) AnchorOnSystemConfigRange() error {
-	tc.mu.Lock()
-	defer tc.mu.Unlock()
-	// Allow this to be called more than once.
-	if bytes.Equal(tc.mu.txn.Key, keys.SystemConfigSpan.Key) {
-		return nil
-	}
-	// The system-config trigger must be run on the system-config range which
-	// means any transaction with the trigger set needs to be anchored to the
-	// system-config range.
-	return tc.setTxnAnchorKeyLocked(keys.SystemConfigSpan.Key)
-}
-
 // TxnStatus is part of the client.TxnSender interface.
 func (tc *TxnCoordSender) TxnStatus() roachpb.TransactionStatus {
 	tc.mu.Lock()

pkg/kv/kvclient/kvcoord/txn_interceptor_committer_test.go

@@ -242,11 +242,7 @@ func TestTxnCommitterStripsInFlightWrites(t *testing.T) {
 	// parallel commits.
 	ba.Requests = nil
 	etArgsWithTrigger := etArgs
-	etArgsWithTrigger.InternalCommitTrigger = &roachpb.InternalCommitTrigger{
-		ModifiedSpanTrigger: &roachpb.ModifiedSpanTrigger{
-			SystemConfigSpan: true,
-		},
-	}
+	etArgsWithTrigger.InternalCommitTrigger = &roachpb.InternalCommitTrigger{}
 	ba.Add(&putArgs, &qiArgs, &etArgsWithTrigger)
 
 	mockSender.MockSend(func(ba roachpb.BatchRequest) (*roachpb.BatchResponse, *roachpb.Error) {

pkg/kv/kvserver/batcheval/cmd_end_transaction.go

@@ -18,7 +18,6 @@ import (
 	"sync/atomic"
 	"time"
 
-	"github.com/cockroachdb/cockroach/pkg/clusterversion"
 	"github.com/cockroachdb/cockroach/pkg/keys"
 	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/abortspan"
 	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/batcheval/result"
@@ -425,17 +424,6 @@ func EndTxn(
 		if err := txnResult.MergeAndDestroy(triggerResult); err != nil {
 			return result.Result{}, err
 		}
-	} else if reply.Txn.Status == roachpb.ABORTED {
-		// If this is the system config span and we're aborted, add a trigger to
-		// potentially gossip now that we've removed an intent. This is important
-		// to deal with cases where previously committed values were not gossipped
-		// due to an outstanding intent.
-		if cArgs.EvalCtx.ContainsKey(keys.SystemConfigSpan.Key) &&
-			!cArgs.EvalCtx.ClusterSettings().Version.IsActive(
-				ctx, clusterversion.DisableSystemConfigGossipTrigger,
-			) {
-			txnResult.Local.MaybeGossipSystemConfigIfHaveFailure = true
-		}
 	}
 
 	return txnResult, nil
@@ -691,31 +679,6 @@ func RunCommitTrigger(
 	}
 	if ct.GetModifiedSpanTrigger() != nil {
 		var pd result.Result
-		if ct.ModifiedSpanTrigger.SystemConfigSpan {
-			// Check if we need to gossip the system config.
-			// NOTE: System config gossiping can only execute correctly if
-			// the transaction record is located on the range that contains
-			// the system span. If a transaction is created which modifies
-			// both system *and* non-system data, it should be ensured that
-			// the transaction record itself is on the system span. This can
-			// be done by making sure a system key is the first key touched
-			// in the transaction.
-			if rec.ContainsKey(keys.SystemConfigSpan.Key) {
-				if err := pd.MergeAndDestroy(
-					result.Result{
-						Local: result.LocalResult{
-							MaybeGossipSystemConfig: true,
-						},
-					},
-				); err != nil {
-					return result.Result{}, err
-				}
-			} else {
-				log.Errorf(ctx, "System configuration span was modified, but the "+
-					"modification trigger is executing on a non-system range. "+
-					"Configuration changes will not be gossiped.")
-			}
-		}
 		if nlSpan := ct.ModifiedSpanTrigger.NodeLivenessSpan; nlSpan != nil {
 			if err := pd.MergeAndDestroy(
 				result.Result{

pkg/kv/kvserver/batcheval/cmd_end_transaction_test.go

@@ -1154,7 +1154,7 @@ func TestCommitWaitBeforeIntentResolutionIfCommitTrigger(t *testing.T) {
 				}
 				if commitTrigger {
 					req.InternalCommitTrigger = &roachpb.InternalCommitTrigger{
-						ModifiedSpanTrigger: &roachpb.ModifiedSpanTrigger{SystemConfigSpan: true},
+						ModifiedSpanTrigger: &roachpb.ModifiedSpanTrigger{NodeLivenessSpan: &roachpb.Span{}},
 					}
 				}
 				var resp roachpb.EndTxnResponse
@@ -1175,7 +1175,7 @@ func TestCommitWaitBeforeIntentResolutionIfCommitTrigger(t *testing.T) {
 
 				if cfg.expError {
 					require.Error(t, err)
-					require.Regexp(t, `txn .* with modified-span \(system-config\) commit trigger needs commit wait`, err)
+					require.Regexp(t, `txn .* with modified-span \(node-liveness\) commit trigger needs commit wait`, err)
 				} else {
 					require.NoError(t, err)
 				}

pkg/kv/kvserver/client_lease_test.go

@@ -22,16 +22,13 @@ import (
 	"time"
 
 	"github.com/cockroachdb/cockroach/pkg/base"
-	"github.com/cockroachdb/cockroach/pkg/clusterversion"
-	"github.com/cockroachdb/cockroach/pkg/config"
 	"github.com/cockroachdb/cockroach/pkg/config/zonepb"
 	"github.com/cockroachdb/cockroach/pkg/gossip"
 	"github.com/cockroachdb/cockroach/pkg/keys"
 	"github.com/cockroachdb/cockroach/pkg/kv"
 	"github.com/cockroachdb/cockroach/pkg/kv/kvserver"
 	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/allocator/storepool"
 	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/kvserverbase"
-	"github.com/cockroachdb/cockroach/pkg/kv/kvserver/liveness/livenesspb"
 	"github.com/cockroachdb/cockroach/pkg/roachpb"
 	"github.com/cockroachdb/cockroach/pkg/server"
 	"github.com/cockroachdb/cockroach/pkg/settings/cluster"
@@ -96,135 +93,6 @@ func TestStoreRangeLease(t *testing.T) {
 	}
 }
 
-// TestStoreGossipSystemData verifies that the system-config and node-liveness
-// data is gossiped at startup in the mixed version state.
-//
-// TODO(ajwerner): Delete this test in 22.2.
-func TestStoreGossipSystemData(t *testing.T) {
-	defer leaktest.AfterTest(t)()
-	defer log.Scope(t).Close(t)
-
-	zcfg := zonepb.DefaultZoneConfig()
-	version := clusterversion.ByKey(clusterversion.DisableSystemConfigGossipTrigger - 1)
-	settings := cluster.MakeTestingClusterSettingsWithVersions(
-		version, version, false, /* initializeVersion */
-	)
-	serverArgs := base.TestServerArgs{
-		Settings: settings,
-		Knobs: base.TestingKnobs{
-			Store: &kvserver.StoreTestingKnobs{
-				DisableMergeQueue: true,
-			},
-			Server: &server.TestingKnobs{
-				DefaultZoneConfigOverride:      &zcfg,
-				BinaryVersionOverride:          version,
-				DisableAutomaticVersionUpgrade: make(chan struct{}),
-			},
-		},
-	}
-	tc := testcluster.StartTestCluster(t, 1,
-		base.TestClusterArgs{
-			ReplicationMode: base.ReplicationManual,
-			ServerArgs:      serverArgs,
-		},
-	)
-	defer tc.Stopper().Stop(context.Background())
-
-	store := tc.GetFirstStoreFromServer(t, 0)
-	splitKey := keys.SystemConfigSplitKey
-	tc.SplitRangeOrFatal(t, splitKey)
-	if _, err := store.DB().Inc(context.Background(), splitKey, 1); err != nil {
-		t.Fatalf("failed to increment: %+v", err)
-	}
-
-	getSystemConfig := func(s *kvserver.Store) *config.SystemConfig {
-		systemConfig := s.Gossip().DeprecatedGetSystemConfig()
-		return systemConfig
-	}
-	getNodeLiveness := func(s *kvserver.Store) livenesspb.Liveness {
-		var liveness livenesspb.Liveness
-		if err := s.Gossip().GetInfoProto(gossip.MakeNodeLivenessKey(1), &liveness); err == nil {
-			return liveness
-		}
-		return livenesspb.Liveness{}
-	}
-
-	// Restart the store and verify that both the system-config and node-liveness
-	// data is gossiped.
-	tc.AddAndStartServer(t, serverArgs)
-	tc.StopServer(0)
-
-	testutils.SucceedsSoon(t, func() error {
-		if !getSystemConfig(tc.GetFirstStoreFromServer(t, 1)).DefaultZoneConfig.Equal(zcfg) {
-			return errors.New("system config not gossiped")
-		}
-		if getNodeLiveness(tc.GetFirstStoreFromServer(t, 1)) == (livenesspb.Liveness{}) {
-			return errors.New("node liveness not gossiped")
-		}
-		return nil
-	})
-}
-
-// TestGossipSystemConfigOnLeaseChange verifies that the system-config gets
-// re-gossiped on lease transfer even if it hasn't changed. This helps prevent
-// situations where a previous leaseholder can restart and not receive the
-// system config because it was the original source of it within the gossip
-// network. This test only applies in the mixed version state.
-//
-// TODO(ajwerner): Remove this test in 22.2.
-func TestGossipSystemConfigOnLeaseChange(t *testing.T) {
-	defer leaktest.AfterTest(t)()
-	defer log.Scope(t).Close(t)
-
-	const numStores = 3
-	tc := testcluster.StartTestCluster(t, numStores,
-		base.TestClusterArgs{
-			ReplicationMode: base.ReplicationManual,
-			ServerArgs: base.TestServerArgs{
-				Knobs: base.TestingKnobs{
-					Store: &kvserver.StoreTestingKnobs{
-						DisableMergeQueue: true,
-					},
-					Server: &server.TestingKnobs{
-						BinaryVersionOverride: clusterversion.ByKey(
-							clusterversion.DisableSystemConfigGossipTrigger - 1,
-						),
-						DisableAutomaticVersionUpgrade: make(chan struct{}),
-					},
-				},
-			},
-		},
-	)
-	defer tc.Stopper().Stop(context.Background())
-
-	key := keys.SystemConfigSpan.Key
-	tc.AddVotersOrFatal(t, key, tc.Target(1), tc.Target(2))
-
-	initialStoreIdx := -1
-	for i := range tc.Servers {
-		if tc.GetFirstStoreFromServer(t, i).Gossip().InfoOriginatedHere(gossip.KeyDeprecatedSystemConfig) {
-			initialStoreIdx = i
-		}
-	}
-	if initialStoreIdx == -1 {
-		t.Fatalf("no store has gossiped system config; gossip contents: %+v", tc.GetFirstStoreFromServer(t, 0).Gossip().GetInfoStatus())
-	}
-
-	newStoreIdx := (initialStoreIdx + 1) % numStores
-	if err := tc.TransferRangeLease(tc.LookupRangeOrFatal(t, key), tc.Target(newStoreIdx)); err != nil {
-		t.Fatalf("Unexpected error %v", err)
-	}
-	testutils.SucceedsSoon(t, func() error {
-		if tc.GetFirstStoreFromServer(t, initialStoreIdx).Gossip().InfoOriginatedHere(gossip.KeyDeprecatedSystemConfig) {
-			return errors.New("system config still most recently gossiped by original leaseholder")
-		}
-		if !tc.GetFirstStoreFromServer(t, newStoreIdx).Gossip().InfoOriginatedHere(gossip.KeyDeprecatedSystemConfig) {
-			return errors.New("system config not most recently gossiped by new leaseholder")
-		}
-		return nil
-	})
-}
-
 func TestGossipNodeLivenessOnLeaseChange(t *testing.T) {
 	defer leaktest.AfterTest(t)()
 	defer log.Scope(t).Close(t)

pkg/kv/kvserver/client_replica_test.go

@@ -3790,10 +3790,6 @@ func TestStrictGCEnforcement(t *testing.T) {
 					s := tc.Server(i)
 					_, r := getFirstStoreReplica(t, s, tableKey)
 					if c := r.SpanConfig(); c.TTL().Seconds() != (time.Duration(exp) * time.Second).Seconds() {
-						_, sysCfg := getFirstStoreReplica(t, tc.Server(i), keys.SystemConfigSpan.Key)
-						sysCfg.RaftLock()
-						require.NoError(t, sysCfg.MaybeGossipSystemConfigRaftMuLocked(ctx))
-						sysCfg.RaftUnlock()
 						return errors.Errorf("expected %d, got %f", exp, c.TTL().Seconds())
 					}
 				}
@@ -3805,11 +3801,8 @@ func TestStrictGCEnforcement(t *testing.T) {
 			sqlDB.Exec(t, `SET CLUSTER SETTING kv.gc_ttl.strict_enforcement.enabled = `+fmt.Sprint(val))
 			testutils.SucceedsSoon(t, func() error {
 				for i := 0; i < tc.NumServers(); i++ {
-					s, r := getFirstStoreReplica(t, tc.Server(i), keys.SystemConfigSpan.Key)
+					s, _ := getFirstStoreReplica(t, tc.Server(i), keys.SystemConfigSpan.Key)
 					if kvserver.StrictGCEnforcement.Get(&s.ClusterSettings().SV) != val {
-						r.RaftLock()
-						require.NoError(t, r.MaybeGossipSystemConfigRaftMuLocked(ctx))
-						r.RaftUnlock()
 						return errors.Errorf("expected %v, got %v", val, !val)
 					}
 				}