Move logging utilities out of the side drawer of util/ and into logging/ (#5606)

71 files changed, 153 insertions, 141 deletions

diff --git a/synapse/app/_base.py b/synapse/app/_base.py
index 9b5c30f506..1ebb7ae539 100644
--- a/synapse/app/_base.py
+++ b/synapse/app/_base.py
@@ -27,7 +27,7 @@ from twisted.protocols.tls import TLSMemoryBIOFactory
 import synapse
 from synapse.app import check_bind_error
 from synapse.crypto import context_factory
-from synapse.util import PreserveLoggingContext
+from synapse.logging.context import PreserveLoggingContext
 from synapse.util.async_helpers import Linearizer
 from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
diff --git a/synapse/app/appservice.py b/synapse/app/appservice.py
index 9120bdb143..be44249ed6 100644
--- a/synapse/app/appservice.py
+++ b/synapse/app/appservice.py
@@ -26,6 +26,7 @@ from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext, run_in_background
 from synapse.metrics import RegistryProxy
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
@@ -36,7 +37,6 @@ from synapse.replication.tcp.client import ReplicationClientHandler
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/app/client_reader.py b/synapse/app/client_reader.py
index 90bc79cdda..ff11beca82 100644
--- a/synapse/app/client_reader.py
+++ b/synapse/app/client_reader.py
@@ -27,6 +27,7 @@ from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.http.server import JsonResource
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext
 from synapse.metrics import RegistryProxy
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
@@ -64,7 +65,6 @@ from synapse.rest.client.versions import VersionsRestServlet
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/app/event_creator.py b/synapse/app/event_creator.py
index ff522e4499..cacad25eac 100644
--- a/synapse/app/event_creator.py
+++ b/synapse/app/event_creator.py
@@ -27,6 +27,7 @@ from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.http.server import JsonResource
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext
 from synapse.metrics import RegistryProxy
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
@@ -59,7 +60,6 @@ from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.storage.user_directory import UserDirectoryStore
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/app/federation_reader.py b/synapse/app/federation_reader.py
index 9421420930..11e80dbae0 100644
--- a/synapse/app/federation_reader.py
+++ b/synapse/app/federation_reader.py
@@ -28,6 +28,7 @@ from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.federation.transport.server import TransportLayerServer
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext
 from synapse.metrics import RegistryProxy
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
@@ -48,7 +49,6 @@ from synapse.rest.key.v2 import KeyApiV2Resource
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/app/federation_sender.py b/synapse/app/federation_sender.py
index 969be58d0b..97da7bdcbf 100644
--- a/synapse/app/federation_sender.py
+++ b/synapse/app/federation_sender.py
@@ -27,6 +27,7 @@ from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.federation import send_queue
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext, run_in_background
 from synapse.metrics import RegistryProxy
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
@@ -44,7 +45,6 @@ from synapse.storage.engines import create_engine
 from synapse.types import ReadReceipt
 from synapse.util.async_helpers import Linearizer
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/app/frontend_proxy.py b/synapse/app/frontend_proxy.py
index 2fd7d57ebf..417a10bbd2 100644
--- a/synapse/app/frontend_proxy.py
+++ b/synapse/app/frontend_proxy.py
@@ -29,6 +29,7 @@ from synapse.config.logger import setup_logging
 from synapse.http.server import JsonResource
 from synapse.http.servlet import RestServlet, parse_json_object_from_request
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext
 from synapse.metrics import RegistryProxy
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
@@ -41,7 +42,6 @@ from synapse.rest.client.v2_alpha._base import client_patterns
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index 49da105cf6..639b1429c0 100755
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -54,6 +54,7 @@ from synapse.federation.transport.server import TransportLayerServer
 from synapse.http.additional_resource import AdditionalResource
 from synapse.http.server import RootRedirect
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext
 from synapse.metrics import RegistryProxy
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
@@ -72,7 +73,6 @@ from synapse.storage.engines import IncorrectDatabaseSetup, create_engine
 from synapse.storage.prepare_database import UpgradeDatabaseException, prepare_database
 from synapse.util.caches import CACHE_SIZE_FACTOR
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
 from synapse.util.module_loader import load_module
 from synapse.util.rlimit import change_resource_limit
diff --git a/synapse/app/media_repository.py b/synapse/app/media_repository.py
index cf0e2036c3..f23b9b6eda 100644
--- a/synapse/app/media_repository.py
+++ b/synapse/app/media_repository.py
@@ -27,6 +27,7 @@ from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext
 from synapse.metrics import RegistryProxy
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
@@ -40,7 +41,6 @@ from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.storage.media_repository import MediaRepositoryStore
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/app/pusher.py b/synapse/app/pusher.py
index df29ea5ecb..4f929edf86 100644
--- a/synapse/app/pusher.py
+++ b/synapse/app/pusher.py
@@ -26,6 +26,7 @@ from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext, run_in_background
 from synapse.metrics import RegistryProxy
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import __func__
@@ -38,7 +39,6 @@ from synapse.server import HomeServer
 from synapse.storage import DataStore
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/app/synchrotron.py b/synapse/app/synchrotron.py
index 858949910d..de4797fddc 100644
--- a/synapse/app/synchrotron.py
+++ b/synapse/app/synchrotron.py
@@ -31,6 +31,7 @@ from synapse.config.logger import setup_logging
 from synapse.handlers.presence import PresenceHandler, get_interested_parties
 from synapse.http.server import JsonResource
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext, run_in_background
 from synapse.metrics import RegistryProxy
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore, __func__
@@ -57,7 +58,6 @@ from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.storage.presence import UserPresenceState
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.stringutils import random_string
 from synapse.util.versionstring import get_version_string
diff --git a/synapse/app/user_dir.py b/synapse/app/user_dir.py
index 2d9d2e1bbc..1177ddd72e 100644
--- a/synapse/app/user_dir.py
+++ b/synapse/app/user_dir.py
@@ -28,6 +28,7 @@ from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.http.server import JsonResource
 from synapse.http.site import SynapseSite
+from synapse.logging.context import LoggingContext, run_in_background
 from synapse.metrics import RegistryProxy
 from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
@@ -46,7 +47,6 @@ from synapse.storage.engines import create_engine
 from synapse.storage.user_directory import UserDirectoryStore
 from synapse.util.caches.stream_change_cache import StreamChangeCache
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/appservice/scheduler.py b/synapse/appservice/scheduler.py
index b54bf5411f..e5b36494f5 100644
--- a/synapse/appservice/scheduler.py
+++ b/synapse/appservice/scheduler.py
@@ -53,8 +53,8 @@ import logging
 from twisted.internet import defer
 
 from synapse.appservice import ApplicationServiceState
+from synapse.logging.context import run_in_background
 from synapse.metrics.background_process_metrics import run_as_background_process
-from synapse.util.logcontext import run_in_background
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/config/logger.py b/synapse/config/logger.py
index 931aec41c0..0f5554211c 100644
--- a/synapse/config/logger.py
+++ b/synapse/config/logger.py
@@ -24,7 +24,7 @@ from twisted.logger import STDLibLogObserver, globalLogBeginner
 
 import synapse
 from synapse.app import _base as appbase
-from synapse.util.logcontext import LoggingContextFilter
+from synapse.logging.context import LoggingContextFilter
 from synapse.util.versionstring import get_version_string
 
 from ._base import Config
@@ -40,7 +40,7 @@ formatters:
 
 filters:
     context:
-        (): synapse.util.logcontext.LoggingContextFilter
+        (): synapse.logging.context.LoggingContextFilter
         request: ""
 
 handlers:
diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py
index 10c2eb7f0f..341c863152 100644
--- a/synapse/crypto/keyring.py
+++ b/synapse/crypto/keyring.py
@@ -44,15 +44,16 @@ from synapse.api.errors import (
     RequestSendFailed,
     SynapseError,
 )
-from synapse.storage.keys import FetchKeyResult
-from synapse.util import logcontext, unwrapFirstError
-from synapse.util.async_helpers import yieldable_gather_results
-from synapse.util.logcontext import (
+from synapse.logging.context import (
     LoggingContext,
     PreserveLoggingContext,
+    make_deferred_yieldable,
     preserve_fn,
     run_in_background,
 )
+from synapse.storage.keys import FetchKeyResult
+from synapse.util import unwrapFirstError
+from synapse.util.async_helpers import yieldable_gather_results
 from synapse.util.metrics import Measure
 from synapse.util.retryutils import NotRetryingDestination
 
@@ -140,7 +141,7 @@ class Keyring(object):
         """
         req = VerifyJsonRequest(server_name, json_object, validity_time, request_name)
         requests = (req,)
-        return logcontext.make_deferred_yieldable(self._verify_objects(requests)[0])
+        return make_deferred_yieldable(self._verify_objects(requests)[0])
 
     def verify_json_objects_for_server(self, server_and_json):
         """Bulk verifies signatures of json objects, bulk fetching keys as
@@ -557,7 +558,7 @@ class BaseV2KeyFetcher(object):
 
         signed_key_json_bytes = encode_canonical_json(signed_key_json)
 
-        yield logcontext.make_deferred_yieldable(
+        yield make_deferred_yieldable(
             defer.gatherResults(
                 [
                     run_in_background(
@@ -612,7 +613,7 @@ class PerspectivesKeyFetcher(BaseV2KeyFetcher):
 
             defer.returnValue({})
 
-        results = yield logcontext.make_deferred_yieldable(
+        results = yield make_deferred_yieldable(
             defer.gatherResults(
                 [run_in_background(get_key, server) for server in self.key_servers],
                 consumeErrors=True,
diff --git a/synapse/events/snapshot.py b/synapse/events/snapshot.py
index a96cdada3d..a9545e6c1b 100644
--- a/synapse/events/snapshot.py
+++ b/synapse/events/snapshot.py
@@ -19,7 +19,7 @@ from frozendict import frozendict
 
 from twisted.internet import defer
 
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 
 
 class EventContext(object):
diff --git a/synapse/federation/federation_base.py b/synapse/federation/federation_base.py
index 1e925b19e7..f7bb806ae7 100644
--- a/synapse/federation/federation_base.py
+++ b/synapse/federation/federation_base.py
@@ -27,8 +27,14 @@ from synapse.crypto.event_signing import check_event_content_hash
 from synapse.events import event_type_from_format_version
 from synapse.events.utils import prune_event
 from synapse.http.servlet import assert_params_in_dict
+from synapse.logging.context import (
+    LoggingContext,
+    PreserveLoggingContext,
+    make_deferred_yieldable,
+    preserve_fn,
+)
 from synapse.types import get_domain_from_id
-from synapse.util import logcontext, unwrapFirstError
+from synapse.util import unwrapFirstError
 
 logger = logging.getLogger(__name__)
 
@@ -73,7 +79,7 @@ class FederationBase(object):
         @defer.inlineCallbacks
         def handle_check_result(pdu, deferred):
             try:
-                res = yield logcontext.make_deferred_yieldable(deferred)
+                res = yield make_deferred_yieldable(deferred)
             except SynapseError:
                 res = None
 
@@ -102,10 +108,10 @@ class FederationBase(object):
 
             defer.returnValue(res)
 
-        handle = logcontext.preserve_fn(handle_check_result)
+        handle = preserve_fn(handle_check_result)
         deferreds2 = [handle(pdu, deferred) for pdu, deferred in zip(pdus, deferreds)]
 
-        valid_pdus = yield logcontext.make_deferred_yieldable(
+        valid_pdus = yield make_deferred_yieldable(
             defer.gatherResults(deferreds2, consumeErrors=True)
         ).addErrback(unwrapFirstError)
 
@@ -115,7 +121,7 @@ class FederationBase(object):
             defer.returnValue([p for p in valid_pdus if p])
 
     def _check_sigs_and_hash(self, room_version, pdu):
-        return logcontext.make_deferred_yieldable(
+        return make_deferred_yieldable(
             self._check_sigs_and_hashes(room_version, [pdu])[0]
         )
 
@@ -133,14 +139,14 @@ class FederationBase(object):
               * returns a redacted version of the event (if the signature
                 matched but the hash did not)
               * throws a SynapseError if the signature check failed.
-            The deferreds run their callbacks in the sentinel logcontext.
+            The deferreds run their callbacks in the sentinel
         """
         deferreds = _check_sigs_on_pdus(self.keyring, room_version, pdus)
 
-        ctx = logcontext.LoggingContext.current_context()
+        ctx = LoggingContext.current_context()
 
         def callback(_, pdu):
-            with logcontext.PreserveLoggingContext(ctx):
+            with PreserveLoggingContext(ctx):
                 if not check_event_content_hash(pdu):
                     # let's try to distinguish between failures because the event was
                     # redacted (which are somewhat expected) vs actual ball-tampering
@@ -178,7 +184,7 @@ class FederationBase(object):
 
         def errback(failure, pdu):
             failure.trap(SynapseError)
-            with logcontext.PreserveLoggingContext(ctx):
+            with PreserveLoggingContext(ctx):
                 logger.warn(
                     "Signature check failed for %s: %s",
                     pdu.event_id,
diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py
index 3883eb525e..3cb4b94420 100644
--- a/synapse/federation/federation_client.py
+++ b/synapse/federation/federation_client.py
@@ -39,10 +39,10 @@ from synapse.api.room_versions import (
 )
 from synapse.events import builder, room_version_to_event_format
 from synapse.federation.federation_base import FederationBase, event_from_pdu_json
-from synapse.util import logcontext, unwrapFirstError
+from synapse.logging.context import make_deferred_yieldable, run_in_background
+from synapse.logging.utils import log_function
+from synapse.util import unwrapFirstError
 from synapse.util.caches.expiringcache import ExpiringCache
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
-from synapse.util.logutils import log_function
 from synapse.util.retryutils import NotRetryingDestination
 
 logger = logging.getLogger(__name__)
@@ -207,7 +207,7 @@ class FederationClient(FederationBase):
         ]
 
         # FIXME: We should handle signature failures more gracefully.
-        pdus[:] = yield logcontext.make_deferred_yieldable(
+        pdus[:] = yield make_deferred_yieldable(
             defer.gatherResults(
                 self._check_sigs_and_hashes(room_version, pdus), consumeErrors=True
             ).addErrback(unwrapFirstError)
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index 2e0cebb638..8c0a18b120 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -42,6 +42,8 @@ from synapse.federation.federation_base import FederationBase, event_from_pdu_js
 from synapse.federation.persistence import TransactionActions
 from synapse.federation.units import Edu, Transaction
 from synapse.http.endpoint import parse_server_name
+from synapse.logging.context import nested_logging_context
+from synapse.logging.utils import log_function
 from synapse.replication.http.federation import (
     ReplicationFederationSendEduRestServlet,
     ReplicationGetQueryRestServlet,
@@ -50,8 +52,6 @@ from synapse.types import get_domain_from_id
 from synapse.util import glob_to_regex
 from synapse.util.async_helpers import Linearizer, concurrently_execute
 from synapse.util.caches.response_cache import ResponseCache
-from synapse.util.logcontext import nested_logging_context
-from synapse.util.logutils import log_function
 
 # when processing incoming transactions, we try to handle multiple rooms in
 # parallel, up to this limit.
diff --git a/synapse/federation/persistence.py b/synapse/federation/persistence.py
index 7535f79203..d086e04243 100644
--- a/synapse/federation/persistence.py
+++ b/synapse/federation/persistence.py
@@ -23,7 +23,7 @@ import logging
 
 from twisted.internet import defer
 
-from synapse.util.logutils import log_function
+from synapse.logging.utils import log_function
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/federation/sender/__init__.py b/synapse/federation/sender/__init__.py
index 766c5a37cd..d46f4aaeb1 100644
--- a/synapse/federation/sender/__init__.py
+++ b/synapse/federation/sender/__init__.py
@@ -26,6 +26,11 @@ from synapse.federation.sender.per_destination_queue import PerDestinationQueue
 from synapse.federation.sender.transaction_manager import TransactionManager
 from synapse.federation.units import Edu
 from synapse.handlers.presence import get_interested_remotes
+from synapse.logging.context import (
+    make_deferred_yieldable,
+    preserve_fn,
+    run_in_background,
+)
 from synapse.metrics import (
     LaterGauge,
     event_processing_loop_counter,
@@ -33,7 +38,6 @@ from synapse.metrics import (
     events_processed_counter,
 )
 from synapse.metrics.background_process_metrics import run_as_background_process
-from synapse.util import logcontext
 from synapse.util.metrics import measure_func
 
 logger = logging.getLogger(__name__)
@@ -210,10 +214,10 @@ class FederationSender(object):
                 for event in events:
                     events_by_room.setdefault(event.room_id, []).append(event)
 
-                yield logcontext.make_deferred_yieldable(
+                yield make_deferred_yieldable(
                     defer.gatherResults(
                         [
-                            logcontext.run_in_background(handle_room_events, evs)
+                            run_in_background(handle_room_events, evs)
                             for evs in itervalues(events_by_room)
                         ],
                         consumeErrors=True,
@@ -360,7 +364,7 @@ class FederationSender(object):
         for queue in queues:
             queue.flush_read_receipts_for_room(room_id)
 
-    @logcontext.preserve_fn  # the caller should not yield on this
+    @preserve_fn  # the caller should not yield on this
     @defer.inlineCallbacks
     def send_presence(self, states):
         """Send the new presence states to the appropriate destinations.
diff --git a/synapse/federation/transport/client.py b/synapse/federation/transport/client.py
index aecd142309..1aae9ec9e7 100644
--- a/synapse/federation/transport/client.py
+++ b/synapse/federation/transport/client.py
@@ -22,7 +22,7 @@ from twisted.internet import defer
 
 from synapse.api.constants import Membership
 from synapse.api.urls import FEDERATION_V1_PREFIX, FEDERATION_V2_PREFIX
-from synapse.util.logutils import log_function
+from synapse.logging.utils import log_function
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/federation/transport/server.py b/synapse/federation/transport/server.py
index 955f0f4308..2efdcff7ef 100644
--- a/synapse/federation/transport/server.py
+++ b/synapse/federation/transport/server.py
@@ -36,8 +36,8 @@ from synapse.http.servlet import (
     parse_json_object_from_request,
     parse_string_from_args,
 )
+from synapse.logging.context import run_in_background
 from synapse.types import ThirdPartyInstanceID, get_domain_from_id
-from synapse.util.logcontext import run_in_background
 from synapse.util.ratelimitutils import FederationRateLimiter
 from synapse.util.versionstring import get_version_string
 
diff --git a/synapse/groups/attestations.py b/synapse/groups/attestations.py
index e73757570c..f497711133 100644
--- a/synapse/groups/attestations.py
+++ b/synapse/groups/attestations.py
@@ -43,9 +43,9 @@ from signedjson.sign import sign_json
 from twisted.internet import defer
 
 from synapse.api.errors import HttpResponseException, RequestSendFailed, SynapseError
+from synapse.logging.context import run_in_background
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.types import get_domain_from_id
-from synapse.util.logcontext import run_in_background
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/handlers/account_validity.py b/synapse/handlers/account_validity.py
index edb48054a0..1f1708ba7d 100644
--- a/synapse/handlers/account_validity.py
+++ b/synapse/handlers/account_validity.py
@@ -22,10 +22,10 @@ from email.mime.text import MIMEText
 from twisted.internet import defer
 
 from synapse.api.errors import StoreError
+from synapse.logging.context import make_deferred_yieldable
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.types import UserID
 from synapse.util import stringutils
-from synapse.util.logcontext import make_deferred_yieldable
 
 try:
     from synapse.push.mailer import load_jinja2_templates
diff --git a/synapse/handlers/appservice.py b/synapse/handlers/appservice.py
index 5cc89d43f6..8f089f0e33 100644
--- a/synapse/handlers/appservice.py
+++ b/synapse/handlers/appservice.py
@@ -23,13 +23,13 @@ from twisted.internet import defer
 
 import synapse
 from synapse.api.constants import EventTypes
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.metrics import (
     event_processing_loop_counter,
     event_processing_loop_room_count,
 )
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.util import log_failure
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.util.metrics import Measure
 
 logger = logging.getLogger(__name__)
diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py
index c8c1ed3246..ef5585aa99 100644
--- a/synapse/handlers/auth.py
+++ b/synapse/handlers/auth.py
@@ -36,9 +36,9 @@ from synapse.api.errors import (
     SynapseError,
 )
 from synapse.api.ratelimiting import Ratelimiter
+from synapse.logging.context import defer_to_thread
 from synapse.module_api import ModuleApi
 from synapse.types import UserID
-from synapse.util import logcontext
 from synapse.util.caches.expiringcache import ExpiringCache
 
 from ._base import BaseHandler
@@ -987,7 +987,7 @@ class AuthHandler(BaseHandler):
                 bcrypt.gensalt(self.bcrypt_rounds),
             ).decode("ascii")
 
-        return logcontext.defer_to_thread(self.hs.get_reactor(), _do_hash)
+        return defer_to_thread(self.hs.get_reactor(), _do_hash)
 
     def validate_hash(self, password, stored_hash):
         """Validates that self.hash(password) == stored_hash.
@@ -1013,7 +1013,7 @@ class AuthHandler(BaseHandler):
             if not isinstance(stored_hash, bytes):
                 stored_hash = stored_hash.encode("ascii")
 
-            return logcontext.defer_to_thread(self.hs.get_reactor(), _do_validate_hash)
+            return defer_to_thread(self.hs.get_reactor(), _do_validate_hash)
         else:
             return defer.succeed(False)
 
diff --git a/synapse/handlers/e2e_keys.py b/synapse/handlers/e2e_keys.py
index 807900fe52..55b4ab3a1a 100644
--- a/synapse/handlers/e2e_keys.py
+++ b/synapse/handlers/e2e_keys.py
@@ -23,8 +23,8 @@ from canonicaljson import encode_canonical_json, json
 from twisted.internet import defer
 
 from synapse.api.errors import CodeMessageException, FederationDeniedError, SynapseError
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.types import UserID, get_domain_from_id
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.util.retryutils import NotRetryingDestination
 
 logger = logging.getLogger(__name__)
diff --git a/synapse/handlers/events.py b/synapse/handlers/events.py
index 5836d3c639..6a38328af3 100644
--- a/synapse/handlers/events.py
+++ b/synapse/handlers/events.py
@@ -21,8 +21,8 @@ from twisted.internet import defer
 from synapse.api.constants import EventTypes, Membership
 from synapse.api.errors import AuthError, SynapseError
 from synapse.events import EventBase
+from synapse.logging.utils import log_function
 from synapse.types import UserID
-from synapse.util.logutils import log_function
 from synapse.visibility import filter_events_for_client
 
 from ._base import BaseHandler
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 02d397c498..57be968c67 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -45,6 +45,13 @@ from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, RoomVersions
 from synapse.crypto.event_signing import compute_event_signature
 from synapse.event_auth import auth_types_for_event
 from synapse.events.validator import EventValidator
+from synapse.logging.context import (
+    make_deferred_yieldable,
+    nested_logging_context,
+    preserve_fn,
+    run_in_background,
+)
+from synapse.logging.utils import log_function
 from synapse.replication.http.federation import (
     ReplicationCleanRoomRestServlet,
     ReplicationFederationSendEventsRestServlet,
@@ -52,10 +59,9 @@ from synapse.replication.http.federation import (
 from synapse.replication.http.membership import ReplicationUserJoinedLeftRoomRestServlet
 from synapse.state import StateResolutionStore, resolve_events_with_store
 from synapse.types import UserID, get_domain_from_id
-from synapse.util import logcontext, unwrapFirstError
+from synapse.util import unwrapFirstError
 from synapse.util.async_helpers import Linearizer
 from synapse.util.distributor import user_joined_room
-from synapse.util.logutils import log_function
 from synapse.util.retryutils import NotRetryingDestination
 from synapse.visibility import filter_events_for_server
 
@@ -338,7 +344,7 @@ class FederationHandler(BaseHandler):
 
                         room_version = yield self.store.get_room_version(room_id)
 
-                        with logcontext.nested_logging_context(p):
+                        with nested_logging_context(p):
                             # note that if any of the missing prevs share missing state or
                             # auth events, the requests to fetch those events are deduped
                             # by the get_pdu_cache in federation_client.
@@ -532,7 +538,7 @@ class FederationHandler(BaseHandler):
                 event_id,
                 ev.event_id,
             )
-            with logcontext.nested_logging_context(ev.event_id):
+            with nested_logging_context(ev.event_id):
                 try:
                     yield self.on_receive_pdu(origin, ev, sent_to_us_directly=False)
                 except FederationError as e:
@@ -725,10 +731,10 @@ class FederationHandler(BaseHandler):
                     missing_auth - failed_to_fetch,
                 )
 
-                results = yield logcontext.make_deferred_yieldable(
+                results = yield make_deferred_yieldable(
                     defer.gatherResults(
                         [
-                            logcontext.run_in_background(
+                            run_in_background(
                                 self.federation_client.get_pdu,
                                 [dest],
                                 event_id,
@@ -994,10 +1000,8 @@ class FederationHandler(BaseHandler):
         event_ids = list(extremities.keys())
 
         logger.debug("calling resolve_state_groups in _maybe_backfill")
-        resolve = logcontext.preserve_fn(
-            self.state_handler.resolve_state_groups_for_events
-        )
-        states = yield logcontext.make_deferred_yieldable(
+        resolve = preserve_fn(self.state_handler.resolve_state_groups_for_events)
+        states = yield make_deferred_yieldable(
             defer.gatherResults(
                 [resolve(room_id, [e]) for e in event_ids], consumeErrors=True
             )
@@ -1171,7 +1175,7 @@ class FederationHandler(BaseHandler):
             # lots of requests for missing prev_events which we do actually
             # have. Hence we fire off the deferred, but don't wait for it.
 
-            logcontext.run_in_background(self._handle_queued_pdus, room_queue)
+            run_in_background(self._handle_queued_pdus, room_queue)
 
         defer.returnValue(True)
 
@@ -1191,7 +1195,7 @@ class FederationHandler(BaseHandler):
                     p.event_id,
                     p.room_id,
                 )
-                with logcontext.nested_logging_context(p.event_id):
+                with nested_logging_context(p.event_id):
                     yield self.on_receive_pdu(origin, p, sent_to_us_directly=True)
             except Exception as e:
                 logger.warn(
@@ -1610,7 +1614,7 @@ class FederationHandler(BaseHandler):
             success = True
         finally:
             if not success:
-                logcontext.run_in_background(
+                run_in_background(
                     self.store.remove_push_actions_from_staging, event.event_id
                 )
 
@@ -1629,7 +1633,7 @@ class FederationHandler(BaseHandler):
         @defer.inlineCallbacks
         def prep(ev_info):
             event = ev_info["event"]
-            with logcontext.nested_logging_context(suffix=event.event_id):
+            with nested_logging_context(suffix=event.event_id):
                 res = yield self._prep_event(
                     origin,
                     event,
@@ -1639,12 +1643,9 @@ class FederationHandler(BaseHandler):
                 )
             defer.returnValue(res)
 
-        contexts = yield logcontext.make_deferred_yieldable(
+        contexts = yield make_deferred_yieldable(
             defer.gatherResults(
-                [
-                    logcontext.run_in_background(prep, ev_info)
-                    for ev_info in event_infos
-                ],
+                [run_in_background(prep, ev_info) for ev_info in event_infos],
                 consumeErrors=True,
             )
         )
@@ -2106,10 +2107,10 @@ class FederationHandler(BaseHandler):
 
         room_version = yield self.store.get_room_version(event.room_id)
 
-        different_events = yield logcontext.make_deferred_yieldable(
+        different_events = yield make_deferred_yieldable(
             defer.gatherResults(
                 [
-                    logcontext.run_in_background(
+                    run_in_background(
                         self.store.get_event, d, allow_none=True, allow_rejected=False
                     )
                     for d in different_auth
diff --git a/synapse/handlers/initial_sync.py b/synapse/handlers/initial_sync.py
index a1fe9d116f..54c966c8a6 100644
--- a/synapse/handlers/initial_sync.py
+++ b/synapse/handlers/initial_sync.py
@@ -21,12 +21,12 @@ from synapse.api.constants import EventTypes, Membership
 from synapse.api.errors import AuthError, Codes, SynapseError
 from synapse.events.validator import EventValidator
 from synapse.handlers.presence import format_user_presence_state
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.streams.config import PaginationConfig
 from synapse.types import StreamToken, UserID
 from synapse.util import unwrapFirstError
 from synapse.util.async_helpers import concurrently_execute
 from synapse.util.caches.snapshot_cache import SnapshotCache
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.visibility import filter_events_for_client
 
 from ._base import BaseHandler
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index 683da6bf32..eaeda7a5cb 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -34,13 +34,13 @@ from synapse.api.errors import (
 from synapse.api.room_versions import RoomVersions
 from synapse.api.urls import ConsentURIBuilder
 from synapse.events.validator import EventValidator
+from synapse.logging.context import run_in_background
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.replication.http.send_event import ReplicationSendEventRestServlet
 from synapse.storage.state import StateFilter
 from synapse.types import RoomAlias, UserID, create_requester
 from synapse.util.async_helpers import Linearizer
 from synapse.util.frozenutils import frozendict_json_encoder
-from synapse.util.logcontext import run_in_background
 from synapse.util.metrics import measure_func
 from synapse.visibility import filter_events_for_client
 
diff --git a/synapse/handlers/pagination.py b/synapse/handlers/pagination.py
index 76ee97ddd3..20bcfed334 100644
--- a/synapse/handlers/pagination.py
+++ b/synapse/handlers/pagination.py
@@ -20,10 +20,10 @@ from twisted.python.failure import Failure
 
 from synapse.api.constants import EventTypes, Membership
 from synapse.api.errors import SynapseError
+from synapse.logging.context import run_in_background
 from synapse.storage.state import StateFilter
 from synapse.types import RoomStreamToken
 from synapse.util.async_helpers import ReadWriteLock
-from synapse.util.logcontext import run_in_background
 from synapse.util.stringutils import random_string
 from synapse.visibility import filter_events_for_client
 
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index c80dc2eba0..6f3537e435 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -34,14 +34,14 @@ from twisted.internet import defer
 import synapse.metrics
 from synapse.api.constants import EventTypes, Membership, PresenceState
 from synapse.api.errors import SynapseError
+from synapse.logging.context import run_in_background
+from synapse.logging.utils import log_function
 from synapse.metrics import LaterGauge
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.storage.presence import UserPresenceState
 from synapse.types import UserID, get_domain_from_id
 from synapse.util.async_helpers import Linearizer
 from synapse.util.caches.descriptors import cachedInlineCallbacks
-from synapse.util.logcontext import run_in_background
-from synapse.util.logutils import log_function
 from synapse.util.metrics import Measure
 from synapse.util.wheel_timer import WheelTimer
 
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index a3f550554f..cd1ac0a27a 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -25,6 +25,7 @@ from prometheus_client import Counter
 from twisted.internet import defer
 
 from synapse.api.constants import EventTypes, Membership
+from synapse.logging.context import LoggingContext
 from synapse.push.clientformat import format_push_rules_for_user
 from synapse.storage.roommember import MemberSummary
 from synapse.storage.state import StateFilter
@@ -33,7 +34,6 @@ from synapse.util.async_helpers import concurrently_execute
 from synapse.util.caches.expiringcache import ExpiringCache
 from synapse.util.caches.lrucache import LruCache
 from synapse.util.caches.response_cache import ResponseCache
-from synapse.util.logcontext import LoggingContext
 from synapse.util.metrics import Measure, measure_func
 from synapse.visibility import filter_events_for_client
 
diff --git a/synapse/handlers/typing.py b/synapse/handlers/typing.py
index f8062c8671..c3e0c8fc7e 100644
--- a/synapse/handlers/typing.py
+++ b/synapse/handlers/typing.py
@@ -19,9 +19,9 @@ from collections import namedtuple
 from twisted.internet import defer
 
 from synapse.api.errors import AuthError, SynapseError
+from synapse.logging.context import run_in_background
 from synapse.types import UserID, get_domain_from_id
 from synapse.util.caches.stream_change_cache import StreamChangeCache
-from synapse.util.logcontext import run_in_background
 from synapse.util.metrics import Measure
 from synapse.util.wheel_timer import WheelTimer
 
diff --git a/synapse/http/client.py b/synapse/http/client.py
index 9bc7035c8d..45d5010952 100644
--- a/synapse/http/client.py
+++ b/synapse/http/client.py
@@ -45,9 +45,9 @@ from synapse.http import (
     cancelled_to_request_timed_out_error,
     redact_uri,
 )
+from synapse.logging.context import make_deferred_yieldable
 from synapse.util.async_helpers import timeout_deferred
 from synapse.util.caches import CACHE_SIZE_FACTOR
-from synapse.util.logcontext import make_deferred_yieldable
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/http/federation/matrix_federation_agent.py b/synapse/http/federation/matrix_federation_agent.py
index 414cde0777..054c321a20 100644
--- a/synapse/http/federation/matrix_federation_agent.py
+++ b/synapse/http/federation/matrix_federation_agent.py
@@ -30,9 +30,9 @@ from twisted.web.http_headers import Headers
 from twisted.web.iweb import IAgent
 
 from synapse.http.federation.srv_resolver import SrvResolver, pick_server_from_list
+from synapse.logging.context import make_deferred_yieldable
 from synapse.util import Clock
 from synapse.util.caches.ttlcache import TTLCache
-from synapse.util.logcontext import make_deferred_yieldable
 from synapse.util.metrics import Measure
 
 # period to cache .well-known results for by default
diff --git a/synapse/http/federation/srv_resolver.py b/synapse/http/federation/srv_resolver.py
index 1f22f78a75..ecc88f9b96 100644
--- a/synapse/http/federation/srv_resolver.py
+++ b/synapse/http/federation/srv_resolver.py
@@ -25,7 +25,7 @@ from twisted.internet.error import ConnectError
 from twisted.names import client, dns
 from twisted.names.error import DNSNameError, DomainError
 
-from synapse.util.logcontext import make_deferred_yieldable
+from synapse.logging.context import make_deferred_yieldable
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index 5ef8bb60a3..dee3710f68 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -48,8 +48,8 @@ from synapse.api.errors import (
 from synapse.http import QuieterFileBodyProducer
 from synapse.http.client import BlacklistingAgentWrapper, IPBlacklistingResolver
 from synapse.http.federation.matrix_federation_agent import MatrixFederationAgent
+from synapse.logging.context import make_deferred_yieldable
 from synapse.util.async_helpers import timeout_deferred
-from synapse.util.logcontext import make_deferred_yieldable
 from synapse.util.metrics import Measure
 
 logger = logging.getLogger(__name__)
diff --git a/synapse/http/request_metrics.py b/synapse/http/request_metrics.py
index 62045a918b..46af27c8f6 100644
--- a/synapse/http/request_metrics.py
+++ b/synapse/http/request_metrics.py
@@ -19,8 +19,8 @@ import threading
 
 from prometheus_client.core import Counter, Histogram
 
+from synapse.logging.context import LoggingContext
 from synapse.metrics import LaterGauge
-from synapse.util.logcontext import LoggingContext
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/http/server.py b/synapse/http/server.py
index d993161a3e..72a3d67eb6 100644
--- a/synapse/http/server.py
+++ b/synapse/http/server.py
@@ -39,8 +39,8 @@ from synapse.api.errors import (
     SynapseError,
     UnrecognizedRequestError,
 )
+from synapse.logging.context import preserve_fn
 from synapse.util.caches import intern_dict
-from synapse.util.logcontext import preserve_fn
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/http/site.py b/synapse/http/site.py
index 93f679ea48..df5274c177 100644
--- a/synapse/http/site.py
+++ b/synapse/http/site.py
@@ -19,7 +19,7 @@ from twisted.web.server import Request, Site
 
 from synapse.http import redact_uri
 from synapse.http.request_metrics import RequestMetrics, requests_counter
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
+from synapse.logging.context import LoggingContext, PreserveLoggingContext
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/logging/__init__.py b/synapse/logging/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/synapse/logging/__init__.py
diff --git a/synapse/util/logcontext.py b/synapse/logging/context.py
index 30dfa1d6b2..30dfa1d6b2 100644
--- a/synapse/util/logcontext.py
+++ b/synapse/logging/context.py
diff --git a/synapse/util/logformatter.py b/synapse/logging/formatter.py
index fbf570c756..fbf570c756 100644
--- a/synapse/util/logformatter.py
+++ b/synapse/logging/formatter.py
diff --git a/synapse/util/logutils.py b/synapse/logging/utils.py
index 7df0fa6087..7df0fa6087 100644
--- a/synapse/util/logutils.py
+++ b/synapse/logging/utils.py
diff --git a/synapse/metrics/background_process_metrics.py b/synapse/metrics/background_process_metrics.py
index 167e2c068a..edd6b42db3 100644
--- a/synapse/metrics/background_process_metrics.py
+++ b/synapse/metrics/background_process_metrics.py
@@ -22,7 +22,7 @@ from prometheus_client.core import REGISTRY, Counter, GaugeMetricFamily
 
 from twisted.internet import defer
 
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
+from synapse.logging.context import LoggingContext, PreserveLoggingContext
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/notifier.py b/synapse/notifier.py
index d398078eed..918ef64897 100644
--- a/synapse/notifier.py
+++ b/synapse/notifier.py
@@ -23,12 +23,12 @@ from twisted.internet import defer
 from synapse.api.constants import EventTypes, Membership
 from synapse.api.errors import AuthError
 from synapse.handlers.presence import format_user_presence_state
+from synapse.logging.context import PreserveLoggingContext
+from synapse.logging.utils import log_function
 from synapse.metrics import LaterGauge
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.types import StreamToken
 from synapse.util.async_helpers import ObservableDeferred, timeout_deferred
-from synapse.util.logcontext import PreserveLoggingContext
-from synapse.util.logutils import log_function
 from synapse.util.metrics import Measure
 from synapse.visibility import filter_events_for_client
 
diff --git a/synapse/push/mailer.py b/synapse/push/mailer.py
index 809199fe88..521c6e2cd7 100644
--- a/synapse/push/mailer.py
+++ b/synapse/push/mailer.py
@@ -29,6 +29,7 @@ from twisted.internet import defer
 
 from synapse.api.constants import EventTypes
 from synapse.api.errors import StoreError
+from synapse.logging.context import make_deferred_yieldable
 from synapse.push.presentable_names import (
     calculate_room_name,
     descriptor_from_member_events,
@@ -36,7 +37,6 @@ from synapse.push.presentable_names import (
 )
 from synapse.types import UserID
 from synapse.util.async_helpers import concurrently_execute
-from synapse.util.logcontext import make_deferred_yieldable
 from synapse.visibility import filter_events_for_client
 
 logger = logging.getLogger(__name__)
diff --git a/synapse/replication/tcp/protocol.py b/synapse/replication/tcp/protocol.py
index 97efb835ad..5ffdf2675d 100644
--- a/synapse/replication/tcp/protocol.py
+++ b/synapse/replication/tcp/protocol.py
@@ -62,9 +62,9 @@ from twisted.internet import defer
 from twisted.protocols.basic import LineOnlyReceiver
 from twisted.python.failure import Failure
 
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.metrics import LaterGauge
 from synapse.metrics.background_process_metrics import run_as_background_process
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.util.stringutils import random_string
 
 from .commands import (
diff --git a/synapse/rest/client/transactions.py b/synapse/rest/client/transactions.py
index 36404b797d..6da71dc46f 100644
--- a/synapse/rest/client/transactions.py
+++ b/synapse/rest/client/transactions.py
@@ -17,8 +17,8 @@
 to ensure idempotency when performing PUTs using the REST API."""
 import logging
 
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.util.async_helpers import ObservableDeferred
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/rest/media/v1/_base.py b/synapse/rest/media/v1/_base.py
index 3318638d3e..5fefee4dde 100644
--- a/synapse/rest/media/v1/_base.py
+++ b/synapse/rest/media/v1/_base.py
@@ -25,7 +25,7 @@ from twisted.protocols.basic import FileSender
 
 from synapse.api.errors import Codes, SynapseError, cs_error
 from synapse.http.server import finish_request, respond_with_json
-from synapse.util import logcontext
+from synapse.logging.context import make_deferred_yieldable
 from synapse.util.stringutils import is_ascii
 
 logger = logging.getLogger(__name__)
@@ -75,9 +75,7 @@ def respond_with_file(request, media_type, file_path, file_size=None, upload_nam
         add_file_headers(request, media_type, file_size, upload_name)
 
         with open(file_path, "rb") as f:
-            yield logcontext.make_deferred_yieldable(
-                FileSender().beginFileTransfer(f, request)
-            )
+            yield make_deferred_yieldable(FileSender().beginFileTransfer(f, request))
 
         finish_request(request)
     else:
diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py
index df3d985a38..65afffbb42 100644
--- a/synapse/rest/media/v1/media_repository.py
+++ b/synapse/rest/media/v1/media_repository.py
@@ -33,8 +33,8 @@ from synapse.api.errors import (
     RequestSendFailed,
     SynapseError,
 )
+from synapse.logging.context import defer_to_thread
 from synapse.metrics.background_process_metrics import run_as_background_process
-from synapse.util import logcontext
 from synapse.util.async_helpers import Linearizer
 from synapse.util.retryutils import NotRetryingDestination
 from synapse.util.stringutils import random_string
@@ -463,7 +463,7 @@ class MediaRepository(object):
         )
 
         thumbnailer = Thumbnailer(input_path)
-        t_byte_source = yield logcontext.defer_to_thread(
+        t_byte_source = yield defer_to_thread(
             self.hs.get_reactor(),
             self._generate_thumbnail,
             thumbnailer,
@@ -511,7 +511,7 @@ class MediaRepository(object):
         )
 
         thumbnailer = Thumbnailer(input_path)
-        t_byte_source = yield logcontext.defer_to_thread(
+        t_byte_source = yield defer_to_thread(
             self.hs.get_reactor(),
             self._generate_thumbnail,
             thumbnailer,
@@ -596,7 +596,7 @@ class MediaRepository(object):
             return
 
         if thumbnailer.transpose_method is not None:
-            m_width, m_height = yield logcontext.defer_to_thread(
+            m_width, m_height = yield defer_to_thread(
                 self.hs.get_reactor(), thumbnailer.transpose
             )
 
@@ -616,11 +616,11 @@ class MediaRepository(object):
         for (t_width, t_height, t_type), t_method in iteritems(thumbnails):
             # Generate the thumbnail
             if t_method == "crop":
-                t_byte_source = yield logcontext.defer_to_thread(
+                t_byte_source = yield defer_to_thread(
                     self.hs.get_reactor(), thumbnailer.crop, t_width, t_height, t_type
                 )
             elif t_method == "scale":
-                t_byte_source = yield logcontext.defer_to_thread(
+                t_byte_source = yield defer_to_thread(
                     self.hs.get_reactor(), thumbnailer.scale, t_width, t_height, t_type
                 )
             else:
diff --git a/synapse/rest/media/v1/media_storage.py b/synapse/rest/media/v1/media_storage.py
index eff86836fb..25e5ac2848 100644
--- a/synapse/rest/media/v1/media_storage.py
+++ b/synapse/rest/media/v1/media_storage.py
@@ -24,9 +24,8 @@ import six
 from twisted.internet import defer
 from twisted.protocols.basic import FileSender
 
-from synapse.util import logcontext
+from synapse.logging.context import defer_to_thread, make_deferred_yieldable
 from synapse.util.file_consumer import BackgroundFileConsumer
-from synapse.util.logcontext import make_deferred_yieldable
 
 from ._base import Responder
 
@@ -65,7 +64,7 @@ class MediaStorage(object):
 
         with self.store_into_file(file_info) as (f, fname, finish_cb):
             # Write to the main repository
-            yield logcontext.defer_to_thread(
+            yield defer_to_thread(
                 self.hs.get_reactor(), _write_file_synchronously, source, f
             )
             yield finish_cb()
diff --git a/synapse/rest/media/v1/preview_url_resource.py b/synapse/rest/media/v1/preview_url_resource.py
index 053346fb86..5871737bfd 100644
--- a/synapse/rest/media/v1/preview_url_resource.py
+++ b/synapse/rest/media/v1/preview_url_resource.py
@@ -42,11 +42,11 @@ from synapse.http.server import (
     wrap_json_request_handler,
 )
 from synapse.http.servlet import parse_integer, parse_string
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.rest.media.v1._base import get_filename_from_headers
 from synapse.util.async_helpers import ObservableDeferred
 from synapse.util.caches.expiringcache import ExpiringCache
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.util.stringutils import random_string
 
 from ._base import FileInfo
diff --git a/synapse/rest/media/v1/storage_provider.py b/synapse/rest/media/v1/storage_provider.py
index 359b45ebfc..e8f559acc1 100644
--- a/synapse/rest/media/v1/storage_provider.py
+++ b/synapse/rest/media/v1/storage_provider.py
@@ -20,8 +20,7 @@ import shutil
 from twisted.internet import defer
 
 from synapse.config._base import Config
-from synapse.util import logcontext
-from synapse.util.logcontext import run_in_background
+from synapse.logging.context import defer_to_thread, run_in_background
 
 from .media_storage import FileResponder
 
@@ -125,7 +124,7 @@ class FileStorageProviderBackend(StorageProvider):
         if not os.path.exists(dirname):
             os.makedirs(dirname)
 
-        return logcontext.defer_to_thread(
+        return defer_to_thread(
             self.hs.get_reactor(), shutil.copyfile, primary_fname, backup_fname
         )
 
diff --git a/synapse/state/__init__.py b/synapse/state/__init__.py
index 1b454a56a1..9f708fa205 100644
--- a/synapse/state/__init__.py
+++ b/synapse/state/__init__.py
@@ -28,11 +28,11 @@ from twisted.internet import defer
 from synapse.api.constants import EventTypes
 from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, StateResolutionVersions
 from synapse.events.snapshot import EventContext
+from synapse.logging.utils import log_function
 from synapse.state import v1, v2
 from synapse.util.async_helpers import Linearizer
 from synapse.util.caches import get_cache_factor_for
 from synapse.util.caches.expiringcache import ExpiringCache
-from synapse.util.logutils import log_function
 from synapse.util.metrics import Measure
 
 logger = logging.getLogger(__name__)
diff --git a/synapse/storage/_base.py b/synapse/storage/_base.py
index 29589853c6..2f940dbae6 100644
--- a/synapse/storage/_base.py
+++ b/synapse/storage/_base.py
@@ -30,12 +30,12 @@ from prometheus_client import Histogram
 from twisted.internet import defer
 
 from synapse.api.errors import StoreError
+from synapse.logging.context import LoggingContext, PreserveLoggingContext
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.storage.engines import PostgresEngine, Sqlite3Engine
 from synapse.types import get_domain_from_id
 from synapse.util import batch_iter
 from synapse.util.caches.descriptors import Cache
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
 from synapse.util.stringutils import exception_to_unicode
 
 # import a function which will return a monotonic time, in seconds
diff --git a/synapse/storage/events.py b/synapse/storage/events.py
index 86f8485704..b486ca50eb 100644
--- a/synapse/storage/events.py
+++ b/synapse/storage/events.py
@@ -33,6 +33,8 @@ from synapse.api.constants import EventTypes
 from synapse.api.errors import SynapseError
 from synapse.events import EventBase  # noqa: F401
 from synapse.events.snapshot import EventContext  # noqa: F401
+from synapse.logging.context import PreserveLoggingContext, make_deferred_yieldable
+from synapse.logging.utils import log_function
 from synapse.metrics import BucketCollector
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.state import StateResolutionStore
@@ -45,8 +47,6 @@ from synapse.util import batch_iter
 from synapse.util.async_helpers import ObservableDeferred
 from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
 from synapse.util.frozenutils import frozendict_json_encoder
-from synapse.util.logcontext import PreserveLoggingContext, make_deferred_yieldable
-from synapse.util.logutils import log_function
 from synapse.util.metrics import Measure
 
 logger = logging.getLogger(__name__)
diff --git a/synapse/storage/events_worker.py b/synapse/storage/events_worker.py
index 6d680d405a..09db872511 100644
--- a/synapse/storage/events_worker.py
+++ b/synapse/storage/events_worker.py
@@ -29,14 +29,14 @@ from synapse.api.room_versions import EventFormatVersions
 from synapse.events import FrozenEvent, event_type_from_format_version  # noqa: F401
 from synapse.events.snapshot import EventContext  # noqa: F401
 from synapse.events.utils import prune_event
-from synapse.metrics.background_process_metrics import run_as_background_process
-from synapse.types import get_domain_from_id
-from synapse.util.logcontext import (
+from synapse.logging.context import (
     LoggingContext,
     PreserveLoggingContext,
     make_deferred_yieldable,
     run_in_background,
 )
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.types import get_domain_from_id
 from synapse.util.metrics import Measure
 
 from ._base import SQLBaseStore
diff --git a/synapse/storage/stream.py b/synapse/storage/stream.py
index d9482a3843..386a9dbe14 100644
--- a/synapse/storage/stream.py
+++ b/synapse/storage/stream.py
@@ -41,12 +41,12 @@ from six.moves import range
 
 from twisted.internet import defer
 
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.storage._base import SQLBaseStore
 from synapse.storage.engines import PostgresEngine
 from synapse.storage.events_worker import EventsWorkerStore
 from synapse.types import RoomStreamToken
 from synapse.util.caches.stream_change_cache import StreamChangeCache
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/util/__init__.py b/synapse/util/__init__.py
index 954e32fb2a..c6d2ce4404 100644
--- a/synapse/util/__init__.py
+++ b/synapse/util/__init__.py
@@ -21,10 +21,14 @@ import attr
 
 from twisted.internet import defer, task
 
-from synapse.util.logcontext import PreserveLoggingContext
+from synapse.logging import context, formatter
 
 logger = logging.getLogger(__name__)
 
+# Compatibility alias, for existing logconfigs.
+logcontext = context
+logformatter = formatter
+
 
 def unwrapFirstError(failure):
     # defer.gatherResults and DeferredLists wrap failures.
@@ -46,7 +50,7 @@ class Clock(object):
     @defer.inlineCallbacks
     def sleep(self, seconds):
         d = defer.Deferred()
-        with PreserveLoggingContext():
+        with context.PreserveLoggingContext():
             self._reactor.callLater(seconds, d.callback, seconds)
             res = yield d
         defer.returnValue(res)
@@ -91,10 +95,10 @@ class Clock(object):
         """
 
         def wrapped_callback(*args, **kwargs):
-            with PreserveLoggingContext():
+            with context.PreserveLoggingContext():
                 callback(*args, **kwargs)
 
-        with PreserveLoggingContext():
+        with context.PreserveLoggingContext():
             return self._reactor.callLater(delay, wrapped_callback, *args, **kwargs)
 
     def cancel_call_later(self, timer, ignore_errs=False):
diff --git a/synapse/util/async_helpers.py b/synapse/util/async_helpers.py
index 7757b8708a..58a6b8764f 100644
--- a/synapse/util/async_helpers.py
+++ b/synapse/util/async_helpers.py
@@ -23,13 +23,12 @@ from twisted.internet import defer
 from twisted.internet.defer import CancelledError
 from twisted.python import failure
 
-from synapse.util import Clock, logcontext, unwrapFirstError
-
-from .logcontext import (
+from synapse.logging.context import (
     PreserveLoggingContext,
     make_deferred_yieldable,
     run_in_background,
 )
+from synapse.util import Clock, unwrapFirstError
 
 logger = logging.getLogger(__name__)
 
@@ -153,7 +152,7 @@ def concurrently_execute(func, args, limit):
         except StopIteration:
             pass
 
-    return logcontext.make_deferred_yieldable(
+    return make_deferred_yieldable(
         defer.gatherResults(
             [run_in_background(_concurrently_execute_inner) for _ in range(limit)],
             consumeErrors=True,
@@ -174,7 +173,7 @@ def yieldable_gather_results(func, iter, *args, **kwargs):
         Deferred[list]: Resolved when all functions have been invoked, or errors if
         one of the function calls fails.
     """
-    return logcontext.make_deferred_yieldable(
+    return make_deferred_yieldable(
         defer.gatherResults(
             [run_in_background(func, item, *args, **kwargs) for item in iter],
             consumeErrors=True,
diff --git a/synapse/util/caches/descriptors.py b/synapse/util/caches/descriptors.py
index d2f25063aa..675db2f448 100644
--- a/synapse/util/caches/descriptors.py
+++ b/synapse/util/caches/descriptors.py
@@ -24,7 +24,8 @@ from six import itervalues, string_types
 
 from twisted.internet import defer
 
-from synapse.util import logcontext, unwrapFirstError
+from synapse.logging.context import make_deferred_yieldable, preserve_fn
+from synapse.util import unwrapFirstError
 from synapse.util.async_helpers import ObservableDeferred
 from synapse.util.caches import get_cache_factor_for
 from synapse.util.caches.lrucache import LruCache
@@ -388,7 +389,7 @@ class CacheDescriptor(_CacheDescriptorBase):
 
             except KeyError:
                 ret = defer.maybeDeferred(
-                    logcontext.preserve_fn(self.function_to_call), obj, *args, **kwargs
+                    preserve_fn(self.function_to_call), obj, *args, **kwargs
                 )
 
                 def onErr(f):
@@ -408,7 +409,7 @@ class CacheDescriptor(_CacheDescriptorBase):
                 observer = result_d.observe()
 
             if isinstance(observer, defer.Deferred):
-                return logcontext.make_deferred_yieldable(observer)
+                return make_deferred_yieldable(observer)
             else:
                 return observer
 
@@ -563,7 +564,7 @@ class CacheListDescriptor(_CacheDescriptorBase):
 
                 cached_defers.append(
                     defer.maybeDeferred(
-                        logcontext.preserve_fn(self.function_to_call), **args_to_call
+                        preserve_fn(self.function_to_call), **args_to_call
                     ).addCallbacks(complete_all, errback)
                 )
 
@@ -571,7 +572,7 @@ class CacheListDescriptor(_CacheDescriptorBase):
                 d = defer.gatherResults(cached_defers, consumeErrors=True).addCallbacks(
                     lambda _: results, unwrapFirstError
                 )
-                return logcontext.make_deferred_yieldable(d)
+                return make_deferred_yieldable(d)
             else:
                 return results
 
diff --git a/synapse/util/caches/response_cache.py b/synapse/util/caches/response_cache.py
index cbe54d45dd..d6908e169d 100644
--- a/synapse/util/caches/response_cache.py
+++ b/synapse/util/caches/response_cache.py
@@ -16,9 +16,9 @@ import logging
 
 from twisted.internet import defer
 
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.util.async_helpers import ObservableDeferred
 from synapse.util.caches import register_cache
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 
 logger = logging.getLogger(__name__)
 
@@ -78,7 +78,7 @@ class ResponseCache(object):
 
         *deferred* should run its callbacks in the sentinel logcontext (ie,
         you should wrap normal synapse deferreds with
-        logcontext.run_in_background).
+        synapse.logging.context.run_in_background).
 
         Can return either a new Deferred (which also doesn't follow the synapse
         logcontext rules), or, if *deferred* was already complete, the actual
diff --git a/synapse/util/distributor.py b/synapse/util/distributor.py
index 5a79db821c..45af8d3eeb 100644
--- a/synapse/util/distributor.py
+++ b/synapse/util/distributor.py
@@ -17,8 +17,8 @@ import logging
 
 from twisted.internet import defer
 
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.metrics.background_process_metrics import run_as_background_process
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/util/file_consumer.py b/synapse/util/file_consumer.py
index 629ed44149..8b17d1c8b8 100644
--- a/synapse/util/file_consumer.py
+++ b/synapse/util/file_consumer.py
@@ -17,7 +17,7 @@ from six.moves import queue
 
 from twisted.internet import threads
 
-from synapse.util.logcontext import make_deferred_yieldable, run_in_background
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 
 
 class BackgroundFileConsumer(object):
diff --git a/synapse/util/metrics.py b/synapse/util/metrics.py
index 01284d3cf8..c30b6de19c 100644
--- a/synapse/util/metrics.py
+++ b/synapse/util/metrics.py
@@ -20,8 +20,8 @@ from prometheus_client import Counter
 
 from twisted.internet import defer
 
+from synapse.logging.context import LoggingContext
 from synapse.metrics import InFlightGauge
-from synapse.util.logcontext import LoggingContext
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/util/ratelimitutils.py b/synapse/util/ratelimitutils.py
index 06defa8199..27bceac00e 100644
--- a/synapse/util/ratelimitutils.py
+++ b/synapse/util/ratelimitutils.py
@@ -20,7 +20,7 @@ import logging
 from twisted.internet import defer
 
 from synapse.api.errors import LimitExceededError
-from synapse.util.logcontext import (
+from synapse.logging.context import (
     PreserveLoggingContext,
     make_deferred_yieldable,
     run_in_background,
diff --git a/synapse/util/retryutils.py b/synapse/util/retryutils.py
index 1a77456498..d8d0ceae51 100644
--- a/synapse/util/retryutils.py
+++ b/synapse/util/retryutils.py
@@ -17,7 +17,7 @@ import random
 
 from twisted.internet import defer
 
-import synapse.util.logcontext
+import synapse.logging.context
 from synapse.api.errors import CodeMessageException
 
 logger = logging.getLogger(__name__)
@@ -225,4 +225,4 @@ class RetryDestinationLimiter(object):
                 logger.exception("Failed to store destination_retry_timings")
 
         # we deliberately do this in the background.
-        synapse.util.logcontext.run_in_background(store_retry_timings)
+        synapse.logging.context.run_in_background(store_retry_timings)