diff --git a/test/functional/bip65-cltv-p2p.py b/test/functional/bip65-cltv-p2p.py
index 7e5e4cf68..65ae8de55 100755
--- a/test/functional/bip65-cltv-p2p.py
+++ b/test/functional/bip65-cltv-p2p.py
@@ -109,7 +109,7 @@ class BIP65Test(BitcoinTestFramework):
         node0.send_and_ping(msg_block(block))
         assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip)
 
-        assert wait_until(lambda: "reject" in node0.last_message.keys())
+        wait_until(lambda: "reject" in node0.last_message.keys(), lock=mininode_lock)
         with mininode_lock:
             assert_equal(node0.last_message["reject"].code, REJECT_OBSOLETE)
             assert_equal(node0.last_message["reject"].reason, b'bad-version(0x00000003)')
@@ -138,7 +138,7 @@ class BIP65Test(BitcoinTestFramework):
         node0.send_and_ping(msg_block(block))
         assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip)
 
-        assert wait_until (lambda: "reject" in node0.last_message.keys())
+        wait_until(lambda: "reject" in node0.last_message.keys(), lock=mininode_lock)
         with mininode_lock:
             assert node0.last_message["reject"].code in [REJECT_INVALID, REJECT_NONSTANDARD]
             assert_equal(node0.last_message["reject"].data, block.sha256)
diff --git a/test/functional/bipdersig-p2p.py b/test/functional/bipdersig-p2p.py
index 38a900954..977597089 100755
--- a/test/functional/bipdersig-p2p.py
+++ b/test/functional/bipdersig-p2p.py
@@ -98,7 +98,7 @@ class BIP66Test(BitcoinTestFramework):
         node0.send_and_ping(msg_block(block))
         assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip)
 
-        assert wait_until(lambda: "reject" in node0.last_message.keys())
+        wait_until(lambda: "reject" in node0.last_message.keys(), lock=mininode_lock)
         with mininode_lock:
             assert_equal(node0.last_message["reject"].code, REJECT_OBSOLETE)
             assert_equal(node0.last_message["reject"].reason, b'bad-version(0x00000002)')
@@ -128,7 +128,7 @@ class BIP66Test(BitcoinTestFramework):
         node0.send_and_ping(msg_block(block))
         assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip)
 
-        assert wait_until (lambda: "reject" in node0.last_message.keys())
+        wait_until(lambda: "reject" in node0.last_message.keys(), lock=mininode_lock)
         with mininode_lock:
             # We can receive different reject messages depending on whether
             # bitcoind is running with multiple script check threads. If script
diff --git a/test/functional/disconnect_ban.py b/test/functional/disconnect_ban.py
index 89b68aeb2..19723226d 100755
--- a/test/functional/disconnect_ban.py
+++ b/test/functional/disconnect_ban.py
@@ -5,11 +5,13 @@
 """Test node disconnect and ban behavior"""
 import time
 
-from test_framework.mininode import wait_until
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import (assert_equal,
-                                 assert_raises_jsonrpc,
-                                 connect_nodes_bi)
+from test_framework.util import (
+    assert_equal,
+    assert_raises_jsonrpc,
+    connect_nodes_bi,
+    wait_until,
+)
 
 class DisconnectBanTest(BitcoinTestFramework):
 
@@ -24,7 +26,7 @@ class DisconnectBanTest(BitcoinTestFramework):
         self.log.info("setban: successfully ban single IP address")
         assert_equal(len(self.nodes[1].getpeerinfo()), 2)  # node1 should have 2 connections to node0 at this point
         self.nodes[1].setban("127.0.0.1", "add")
-        assert wait_until(lambda: len(self.nodes[1].getpeerinfo()) == 0, timeout=10)
+        wait_until(lambda: len(self.nodes[1].getpeerinfo()) == 0, timeout=10)
         assert_equal(len(self.nodes[1].getpeerinfo()), 0)  # all nodes must be disconnected at this point
         assert_equal(len(self.nodes[1].listbanned()), 1)
 
@@ -90,7 +92,7 @@ class DisconnectBanTest(BitcoinTestFramework):
         self.log.info("disconnectnode: successfully disconnect node by address")
         address1 = self.nodes[0].getpeerinfo()[0]['addr']
         self.nodes[0].disconnectnode(address=address1)
-        assert wait_until(lambda: len(self.nodes[0].getpeerinfo()) == 1, timeout=10)
+        wait_until(lambda: len(self.nodes[0].getpeerinfo()) == 1, timeout=10)
         assert not [node for node in self.nodes[0].getpeerinfo() if node['addr'] == address1]
 
         self.log.info("disconnectnode: successfully reconnect node")
@@ -101,7 +103,7 @@ class DisconnectBanTest(BitcoinTestFramework):
         self.log.info("disconnectnode: successfully disconnect node by node id")
         id1 = self.nodes[0].getpeerinfo()[0]['id']
         self.nodes[0].disconnectnode(nodeid=id1)
-        assert wait_until(lambda: len(self.nodes[0].getpeerinfo()) == 1, timeout=10)
+        wait_until(lambda: len(self.nodes[0].getpeerinfo()) == 1, timeout=10)
         assert not [node for node in self.nodes[0].getpeerinfo() if node['id'] == id1]
 
 if __name__ == '__main__':
diff --git a/test/functional/example_test.py b/test/functional/example_test.py
index 79940a426..4f9e0a7dd 100755
--- a/test/functional/example_test.py
+++ b/test/functional/example_test.py
@@ -23,13 +23,13 @@ from test_framework.mininode import (
     mininode_lock,
     msg_block,
     msg_getdata,
-    wait_until,
 )
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
     connect_nodes,
     p2p_port,
+    wait_until,
 )
 
 # NodeConnCB is a class containing callbacks to be executed when a P2P
@@ -209,7 +209,7 @@ class ExampleTest(BitcoinTestFramework):
 
         # wait_until() will loop until a predicate condition is met. Use it to test properties of the
         # NodeConnCB objects.
-        assert wait_until(lambda: sorted(blocks) == sorted(list(node2.block_receive_map.keys())), timeout=5)
+        wait_until(lambda: sorted(blocks) == sorted(list(node2.block_receive_map.keys())), timeout=5, lock=mininode_lock)
 
         self.log.info("Check that each block was received only once")
         # The network thread uses a global lock on data access to the NodeConn objects when sending and receiving
diff --git a/test/functional/mempool_persist.py b/test/functional/mempool_persist.py
index e0889fd5e..807edeb7a 100755
--- a/test/functional/mempool_persist.py
+++ b/test/functional/mempool_persist.py
@@ -32,7 +32,6 @@ Test is as follows:
 """
 import time
 
-from test_framework.mininode import wait_until
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import *
 
@@ -69,7 +68,7 @@ class MempoolPersistTest(BitcoinTestFramework):
         self.nodes.append(self.start_node(1, self.options.tmpdir))
         # Give bitcoind a second to reload the mempool
         time.sleep(1)
-        assert wait_until(lambda: len(self.nodes[0].getrawmempool()) == 5)
+        wait_until(lambda: len(self.nodes[0].getrawmempool()) == 5)
         assert_equal(len(self.nodes[1].getrawmempool()), 0)
 
         self.log.debug("Stop-start node0 with -persistmempool=0. Verify that it doesn't load its mempool.dat file.")
@@ -84,7 +83,7 @@ class MempoolPersistTest(BitcoinTestFramework):
         self.stop_nodes()
         self.nodes = []
         self.nodes.append(self.start_node(0, self.options.tmpdir))
-        assert wait_until(lambda: len(self.nodes[0].getrawmempool()) == 5)
+        wait_until(lambda: len(self.nodes[0].getrawmempool()) == 5)
 
 if __name__ == '__main__':
     MempoolPersistTest().main()
diff --git a/test/functional/p2p-compactblocks.py b/test/functional/p2p-compactblocks.py
index ff76e49fb..c5c264765 100755
--- a/test/functional/p2p-compactblocks.py
+++ b/test/functional/p2p-compactblocks.py
@@ -70,7 +70,7 @@ class TestNode(NodeConnCB):
     def request_headers_and_sync(self, locator, hashstop=0):
         self.clear_block_announcement()
         self.get_headers(locator, hashstop)
-        assert wait_until(self.received_block_announcement, timeout=30)
+        wait_until(self.received_block_announcement, timeout=30, lock=mininode_lock)
         self.clear_block_announcement()
 
     # Block until a block announcement for a particular block hash is
@@ -78,7 +78,7 @@ class TestNode(NodeConnCB):
     def wait_for_block_announcement(self, block_hash, timeout=30):
         def received_hash():
             return (block_hash in self.announced_blockhashes)
-        return wait_until(received_hash, timeout=timeout)
+        wait_until(received_hash, timeout=timeout, lock=mininode_lock)
 
     def send_await_disconnect(self, message, timeout=30):
         """Sends a message to the node and wait for disconnect.
@@ -86,11 +86,7 @@ class TestNode(NodeConnCB):
         This is used when we want to send a message into the node that we expect
         will get us disconnected, eg an invalid block."""
         self.send_message(message)
-        success = wait_until(lambda: not self.connected, timeout=timeout)
-        if not success:
-            logger.error("send_await_disconnect failed!")
-            raise AssertionError("send_await_disconnect failed!")
-        return success
+        wait_until(lambda: not self.connected, timeout=timeout, lock=mininode_lock)
 
 class CompactBlocksTest(BitcoinTestFramework):
     def __init__(self):
@@ -150,9 +146,7 @@ class CompactBlocksTest(BitcoinTestFramework):
         # Make sure we get a SENDCMPCT message from our peer
         def received_sendcmpct():
             return (len(test_node.last_sendcmpct) > 0)
-        got_message = wait_until(received_sendcmpct, timeout=30)
-        assert(received_sendcmpct())
-        assert(got_message)
+        wait_until(received_sendcmpct, timeout=30, lock=mininode_lock)
         with mininode_lock:
             # Check that the first version received is the preferred one
             assert_equal(test_node.last_sendcmpct[0].version, preferred_version)
@@ -167,7 +161,6 @@ class CompactBlocksTest(BitcoinTestFramework):
             block_hash = int(node.generate(1)[0], 16)
             peer.wait_for_block_announcement(block_hash, timeout=30)
             assert(peer.block_announced)
-            assert(got_message)
 
             with mininode_lock:
                 assert predicate(peer), (
@@ -282,7 +275,7 @@ class CompactBlocksTest(BitcoinTestFramework):
 
         # Wait until we've seen the block announcement for the resulting tip
         tip = int(node.getbestblockhash(), 16)
-        assert(test_node.wait_for_block_announcement(tip))
+        test_node.wait_for_block_announcement(tip)
 
         # Make sure we will receive a fast-announce compact block
         self.request_cb_announcements(test_node, node, version)
@@ -297,8 +290,7 @@ class CompactBlocksTest(BitcoinTestFramework):
         block.rehash()
 
         # Wait until the block was announced (via compact blocks)
-        wait_until(test_node.received_block_announcement, timeout=30)
-        assert(test_node.received_block_announcement())
+        wait_until(test_node.received_block_announcement, timeout=30, lock=mininode_lock)
 
         # Now fetch and check the compact block
         header_and_shortids = None
@@ -314,8 +306,7 @@ class CompactBlocksTest(BitcoinTestFramework):
             inv = CInv(4, block_hash)  # 4 == "CompactBlock"
             test_node.send_message(msg_getdata([inv]))
 
-        wait_until(test_node.received_block_announcement, timeout=30)
-        assert(test_node.received_block_announcement())
+        wait_until(test_node.received_block_announcement, timeout=30, lock=mininode_lock)
 
         # Now fetch and check the compact block
         header_and_shortids = None
@@ -386,13 +377,11 @@ class CompactBlocksTest(BitcoinTestFramework):
 
             if announce == "inv":
                 test_node.send_message(msg_inv([CInv(2, block.sha256)]))
-                success = wait_until(lambda: "getheaders" in test_node.last_message, timeout=30)
-                assert(success)
+                wait_until(lambda: "getheaders" in test_node.last_message, timeout=30, lock=mininode_lock)
                 test_node.send_header_for_blocks([block])
             else:
                 test_node.send_header_for_blocks([block])
-            success = wait_until(lambda: "getdata" in test_node.last_message, timeout=30)
-            assert(success)
+            wait_until(lambda: "getdata" in test_node.last_message, timeout=30, lock=mininode_lock)
             assert_equal(len(test_node.last_message["getdata"].inv), 1)
             assert_equal(test_node.last_message["getdata"].inv[0].type, 4)
             assert_equal(test_node.last_message["getdata"].inv[0].hash, block.sha256)
@@ -571,8 +560,7 @@ class CompactBlocksTest(BitcoinTestFramework):
         assert_equal(int(node.getbestblockhash(), 16), block.hashPrevBlock)
 
         # We should receive a getdata request
-        success = wait_until(lambda: "getdata" in test_node.last_message, timeout=10)
-        assert(success)
+        wait_until(lambda: "getdata" in test_node.last_message, timeout=10, lock=mininode_lock)
         assert_equal(len(test_node.last_message["getdata"].inv), 1)
         assert(test_node.last_message["getdata"].inv[0].type == 2 or test_node.last_message["getdata"].inv[0].type == 2|MSG_WITNESS_FLAG)
         assert_equal(test_node.last_message["getdata"].inv[0].hash, block.sha256)
@@ -599,8 +587,7 @@ class CompactBlocksTest(BitcoinTestFramework):
             num_to_request = random.randint(1, len(block.vtx))
             msg.block_txn_request.from_absolute(sorted(random.sample(range(len(block.vtx)), num_to_request)))
             test_node.send_message(msg)
-            success = wait_until(lambda: "blocktxn" in test_node.last_message, timeout=10)
-            assert(success)
+            wait_until(lambda: "blocktxn" in test_node.last_message, timeout=10, lock=mininode_lock)
 
             [tx.calc_sha256() for tx in block.vtx]
             with mininode_lock:
@@ -639,22 +626,20 @@ class CompactBlocksTest(BitcoinTestFramework):
         for i in range(MAX_CMPCTBLOCK_DEPTH + 1):
             test_node.clear_block_announcement()
             new_blocks.append(node.generate(1)[0])
-            wait_until(test_node.received_block_announcement, timeout=30)
+            wait_until(test_node.received_block_announcement, timeout=30, lock=mininode_lock)
 
         test_node.clear_block_announcement()
         test_node.send_message(msg_getdata([CInv(4, int(new_blocks[0], 16))]))
-        success = wait_until(lambda: "cmpctblock" in test_node.last_message, timeout=30)
-        assert(success)
+        wait_until(lambda: "cmpctblock" in test_node.last_message, timeout=30, lock=mininode_lock)
 
         test_node.clear_block_announcement()
         node.generate(1)
-        wait_until(test_node.received_block_announcement, timeout=30)
+        wait_until(test_node.received_block_announcement, timeout=30, lock=mininode_lock)
         test_node.clear_block_announcement()
         with mininode_lock:
             test_node.last_message.pop("block", None)
         test_node.send_message(msg_getdata([CInv(4, int(new_blocks[0], 16))]))
-        success = wait_until(lambda: "block" in test_node.last_message, timeout=30)
-        assert(success)
+        wait_until(lambda: "block" in test_node.last_message, timeout=30, lock=mininode_lock)
         with mininode_lock:
             test_node.last_message["block"].block.calc_sha256()
             assert_equal(test_node.last_message["block"].block.sha256, int(new_blocks[0], 16))
@@ -705,7 +690,7 @@ class CompactBlocksTest(BitcoinTestFramework):
         node.submitblock(ToHex(block))
 
         for l in listeners:
-            wait_until(lambda: l.received_block_announcement(), timeout=30)
+            wait_until(lambda: l.received_block_announcement(), timeout=30, lock=mininode_lock)
         with mininode_lock:
             for l in listeners:
                 assert "cmpctblock" in l.last_message
diff --git a/test/functional/p2p-leaktests.py b/test/functional/p2p-leaktests.py
index 5611c876a..f0d4d9a8b 100755
--- a/test/functional/p2p-leaktests.py
+++ b/test/functional/p2p-leaktests.py
@@ -119,11 +119,11 @@ class P2PLeakTest(BitcoinTestFramework):
 
         NetworkThread().start()  # Start up network handling in another thread
 
-        assert wait_until(lambda: no_version_bannode.ever_connected, timeout=10)
-        assert wait_until(lambda: no_version_idlenode.ever_connected, timeout=10)
-        assert wait_until(lambda: no_verack_idlenode.version_received, timeout=10)
-        assert wait_until(lambda: unsupported_service_bit5_node.ever_connected, timeout=10)
-        assert wait_until(lambda: unsupported_service_bit7_node.ever_connected, timeout=10)
+        wait_until(lambda: no_version_bannode.ever_connected, timeout=10, lock=mininode_lock)
+        wait_until(lambda: no_version_idlenode.ever_connected, timeout=10, lock=mininode_lock)
+        wait_until(lambda: no_verack_idlenode.version_received, timeout=10, lock=mininode_lock)
+        wait_until(lambda: unsupported_service_bit5_node.ever_connected, timeout=10, lock=mininode_lock)
+        wait_until(lambda: unsupported_service_bit7_node.ever_connected, timeout=10, lock=mininode_lock)
 
         # Mine a block and make sure that it's not sent to the connected nodes
         self.nodes[0].generate(1)
@@ -158,8 +158,8 @@ class P2PLeakTest(BitcoinTestFramework):
         allowed_service_bit5_node.add_connection(connections[5])
         allowed_service_bit7_node.add_connection(connections[6])
 
-        assert wait_until(lambda: allowed_service_bit5_node.message_count["verack"], timeout=10)
-        assert wait_until(lambda: allowed_service_bit7_node.message_count["verack"], timeout=10)
+        wait_until(lambda: allowed_service_bit5_node.message_count["verack"], timeout=10, lock=mininode_lock)
+        wait_until(lambda: allowed_service_bit7_node.message_count["verack"], timeout=10, lock=mininode_lock)
 
 if __name__ == '__main__':
     P2PLeakTest().main()
diff --git a/test/functional/sendheaders.py b/test/functional/sendheaders.py
index e47e07fb8..6451b097c 100755
--- a/test/functional/sendheaders.py
+++ b/test/functional/sendheaders.py
@@ -128,7 +128,7 @@ class TestNode(NodeConnCB):
         expect_headers = headers if headers != None else []
         expect_inv = inv if inv != None else []
         test_function = lambda: self.block_announced
-        assert(wait_until(test_function, timeout=60))
+        wait_until(test_function, timeout=60, lock=mininode_lock)
         with mininode_lock:
             self.block_announced = False
 
@@ -155,12 +155,12 @@ class TestNode(NodeConnCB):
             return
 
         test_function = lambda: "getdata" in self.last_message and [x.hash for x in self.last_message["getdata"].inv] == hash_list
-        assert(wait_until(test_function, timeout=timeout))
+        wait_until(test_function, timeout=timeout, lock=mininode_lock)
         return
 
     def wait_for_block_announcement(self, block_hash, timeout=60):
         test_function = lambda: self.last_blockhash_announced == block_hash
-        assert(wait_until(test_function, timeout=timeout))
+        wait_until(test_function, timeout=timeout, lock=mininode_lock)
         return
 
     def send_header_for_blocks(self, new_blocks):
diff --git a/test/functional/test_framework/comptool.py b/test/functional/test_framework/comptool.py
index 9f062865a..bfbc0c3b0 100755
--- a/test/functional/test_framework/comptool.py
+++ b/test/functional/test_framework/comptool.py
@@ -19,7 +19,7 @@ TestNode behaves as follows:
 
 from .mininode import *
 from .blockstore import BlockStore, TxStore
-from .util import p2p_port
+from .util import p2p_port, wait_until
 
 import logging
 
@@ -189,7 +189,7 @@ class TestManager(object):
     def wait_for_disconnections(self):
         def disconnected():
             return all(node.closed for node in self.test_nodes)
-        return wait_until(disconnected, timeout=10)
+        wait_until(disconnected, timeout=10, lock=mininode_lock)
 
     def wait_for_verack(self):
         return all(node.wait_for_verack() for node in self.test_nodes)
@@ -197,7 +197,7 @@ class TestManager(object):
     def wait_for_pings(self, counter):
         def received_pongs():
             return all(node.received_ping_response(counter) for node in self.test_nodes)
-        return wait_until(received_pongs)
+        wait_until(received_pongs, lock=mininode_lock)
 
     # sync_blocks: Wait for all connections to request the blockhash given
     # then send get_headers to find out the tip of each node, and synchronize
@@ -210,8 +210,7 @@ class TestManager(object):
             )
 
         # --> error if not requested
-        if not wait_until(blocks_requested, attempts=20*num_blocks):
-            raise AssertionError("Not all nodes requested block")
+        wait_until(blocks_requested, attempts=20*num_blocks, lock=mininode_lock)
 
         # Send getheaders message
         [ c.cb.send_getheaders() for c in self.connections ]
@@ -231,8 +230,7 @@ class TestManager(object):
             )
 
         # --> error if not requested
-        if not wait_until(transaction_requested, attempts=20*num_events):
-            raise AssertionError("Not all nodes requested transaction")
+        wait_until(transaction_requested, attempts=20*num_events, lock=mininode_lock)
 
         # Get the mempool
         [ c.cb.send_mempool() for c in self.connections ]
diff --git a/test/functional/test_framework/mininode.py b/test/functional/test_framework/mininode.py
index a4d85501e..d0753276d 100755
--- a/test/functional/test_framework/mininode.py
+++ b/test/functional/test_framework/mininode.py
@@ -35,7 +35,7 @@ import time
 from threading import RLock, Thread
 
 from test_framework.siphash import siphash256
-from test_framework.util import hex_str_to_bytes, bytes_to_hex_str
+from test_framework.util import hex_str_to_bytes, bytes_to_hex_str, wait_until
 
 BIP0031_VERSION = 60000
 MY_VERSION = 70014  # past bip-31 for ping/pong
@@ -1358,23 +1358,6 @@ class msg_reject(object):
         return "msg_reject: %s %d %s [%064x]" \
             % (self.message, self.code, self.reason, self.data)
 
-# Helper function
-def wait_until(predicate, *, attempts=float('inf'), timeout=float('inf')):
-    if attempts == float('inf') and timeout == float('inf'):
-        timeout = 60
-    attempt = 0
-    elapsed = 0
-
-    while attempt < attempts and elapsed < timeout:
-        with mininode_lock:
-            if predicate():
-                return True
-        attempt += 1
-        elapsed += 0.05
-        time.sleep(0.05)
-
-    return False
-
 class msg_feefilter(object):
     command = b"feefilter"
 
@@ -1591,21 +1574,21 @@ class NodeConnCB(object):
 
     def wait_for_disconnect(self, timeout=60):
         test_function = lambda: not self.connected
-        assert wait_until(test_function, timeout=timeout)
+        wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     # Message receiving helper methods
 
     def wait_for_block(self, blockhash, timeout=60):
         test_function = lambda: self.last_message.get("block") and self.last_message["block"].block.rehash() == blockhash
-        assert wait_until(test_function, timeout=timeout)
+        wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     def wait_for_getdata(self, timeout=60):
         test_function = lambda: self.last_message.get("getdata")
-        assert wait_until(test_function, timeout=timeout)
+        wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     def wait_for_getheaders(self, timeout=60):
         test_function = lambda: self.last_message.get("getheaders")
-        assert wait_until(test_function, timeout=timeout)
+        wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     def wait_for_inv(self, expected_inv, timeout=60):
         """Waits for an INV message and checks that the first inv object in the message was as expected."""
@@ -1614,11 +1597,11 @@ class NodeConnCB(object):
         test_function = lambda: self.last_message.get("inv") and \
                                 self.last_message["inv"].inv[0].type == expected_inv[0].type and \
                                 self.last_message["inv"].inv[0].hash == expected_inv[0].hash
-        assert wait_until(test_function, timeout=timeout)
+        wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     def wait_for_verack(self, timeout=60):
         test_function = lambda: self.message_count["verack"]
-        assert wait_until(test_function, timeout=timeout)
+        wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     # Message sending helper functions
 
@@ -1636,7 +1619,7 @@ class NodeConnCB(object):
     def sync_with_ping(self, timeout=60):
         self.send_message(msg_ping(nonce=self.ping_counter))
         test_function = lambda: self.last_message.get("pong") and self.last_message["pong"].nonce == self.ping_counter
-        assert wait_until(test_function, timeout=timeout)
+        wait_until(test_function, timeout=timeout, lock=mininode_lock)
         self.ping_counter += 1
         return True
 
diff --git a/test/functional/test_framework/util.py b/test/functional/test_framework/util.py
index 4098fd861..a14cda07d 100644
--- a/test/functional/test_framework/util.py
+++ b/test/functional/test_framework/util.py
@@ -157,6 +157,28 @@ def str_to_b64str(string):
 def satoshi_round(amount):
     return Decimal(amount).quantize(Decimal('0.00000001'), rounding=ROUND_DOWN)
 
+def wait_until(predicate, *, attempts=float('inf'), timeout=float('inf'), lock=None):
+    if attempts == float('inf') and timeout == float('inf'):
+        timeout = 60
+    attempt = 0
+    timeout += time.time()
+
+    while attempt < attempts and time.time() < timeout:
+        if lock:
+            with lock:
+                if predicate():
+                    return
+        else:
+            if predicate():
+                return
+        attempt += 1
+        time.sleep(0.05)
+
+    # Print the cause of the timeout
+    assert_greater_than(attempts, attempt)
+    assert_greater_than(timeout, time.time())
+    raise RuntimeError('Unreachable')
+
 # RPC/P2P connection constants and functions
 ############################################