Merge pull request etcd-io#17058 from ahrtr/rollback_lease_lock_20231204

Rollback the pull/14080: which fixed the potential deadlock

server/lease/lessor.go

@@ -281,17 +281,17 @@ func (le *lessor) Grant(id LeaseID, ttl int64) (*Lease, error) {
 	// with longer TTL to reduce renew load.
 	l := NewLease(id, ttl)
 
-	if l.ttl < le.minLeaseTTL {
-		l.ttl = le.minLeaseTTL
-	}
-
 	le.mu.Lock()
 	defer le.mu.Unlock()
 
 	if _, ok := le.leaseMap[id]; ok {
 		return nil, ErrLeaseExists
 	}
 
+	if l.ttl < le.minLeaseTTL {
+		l.ttl = le.minLeaseTTL
+	}
+
 	if le.isPrimary() {
 		l.refresh(0)
 	} else {
@@ -322,11 +322,6 @@ func (le *lessor) Revoke(id LeaseID) error {
 		return ErrLeaseNotFound
 	}
 
-	// We shouldn't delete the lease inside the transaction lock, otherwise
-	// it may lead to deadlock with Grant or Checkpoint operations, which
-	// acquire the le.mu firstly and then the batchTx lock.
-	delete(le.leaseMap, id)
-
 	defer close(l.revokec)
 	// unlock before doing external work
 	le.mu.Unlock()
@@ -345,6 +340,9 @@ func (le *lessor) Revoke(id LeaseID) error {
 		txn.DeleteRange([]byte(key), nil)
 	}
 
+	le.mu.Lock()
+	defer le.mu.Unlock()
+	delete(le.leaseMap, l.ID)
 	// lease deletion needs to be in the same backend transaction with the
 	// kv deletion. Or we might end up with not executing the revoke or not
 	// deleting the keys if etcdserver fails in between.