diff --git a/src/core/ext/filters/client_channel/subchannel.cc b/src/core/ext/filters/client_channel/subchannel.cc
index be2d5558571..1c245ae427a 100644
--- a/src/core/ext/filters/client_channel/subchannel.cc
+++ b/src/core/ext/filters/client_channel/subchannel.cc
@@ -213,11 +213,12 @@ void SubchannelCall::Unref() {
   GRPC_CALL_STACK_UNREF(SUBCHANNEL_CALL_TO_CALL_STACK(this), "");
 }
 
-void SubchannelCall::Unref(const DebugLocation& location, const char* reason) {
+void SubchannelCall::Unref(const DebugLocation& /*location*/,
+                           const char* reason) {
   GRPC_CALL_STACK_UNREF(SUBCHANNEL_CALL_TO_CALL_STACK(this), reason);
 }
 
-void SubchannelCall::Destroy(void* arg, grpc_error* error) {
+void SubchannelCall::Destroy(void* arg, grpc_error* /*error*/) {
   GPR_TIMER_SCOPE("subchannel_call_destroy", 0);
   SubchannelCall* self = static_cast<SubchannelCall*>(arg);
   // Keep some members before destroying the subchannel call.
@@ -300,8 +301,8 @@ void SubchannelCall::IncrementRefCount() {
   GRPC_CALL_STACK_REF(SUBCHANNEL_CALL_TO_CALL_STACK(this), "");
 }
 
-void SubchannelCall::IncrementRefCount(const grpc_core::DebugLocation& location,
-                                       const char* reason) {
+void SubchannelCall::IncrementRefCount(
+    const grpc_core::DebugLocation& /*location*/, const char* reason) {
   GRPC_CALL_STACK_REF(SUBCHANNEL_CALL_TO_CALL_STACK(this), reason);
 }
 
@@ -721,7 +722,7 @@ Subchannel* Subchannel::WeakRef(GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
 
 namespace {
 
-void subchannel_destroy(void* arg, grpc_error* error) {
+void subchannel_destroy(void* arg, grpc_error* /*error*/) {
   Subchannel* self = static_cast<Subchannel*>(arg);
   Delete(self);
 }
@@ -739,7 +740,7 @@ void Subchannel::WeakUnref(GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
   }
 }
 
-Subchannel* Subchannel::RefFromWeakRef(GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
+Subchannel* Subchannel::RefFromWeakRef() {
   for (;;) {
     gpr_atm old_refs = gpr_atm_acq_load(&ref_pair_);
     if (old_refs >= (1 << INTERNAL_REF_BITS)) {
@@ -1008,7 +1009,7 @@ void Subchannel::OnConnectingFinished(void* arg, grpc_error* error) {
 
 namespace {
 
-void ConnectionDestroy(void* arg, grpc_error* error) {
+void ConnectionDestroy(void* arg, grpc_error* /*error*/) {
   grpc_channel_stack* stk = static_cast<grpc_channel_stack*>(arg);
   grpc_channel_stack_destroy(stk);
   gpr_free(stk);
diff --git a/src/core/ext/filters/client_channel/subchannel.h b/src/core/ext/filters/client_channel/subchannel.h
index fde19dc4f2c..d2b822b8397 100644
--- a/src/core/ext/filters/client_channel/subchannel.h
+++ b/src/core/ext/filters/client_channel/subchannel.h
@@ -43,8 +43,7 @@
 // For debugging refcounting.
 #ifndef NDEBUG
 #define GRPC_SUBCHANNEL_REF(p, r) (p)->Ref(__FILE__, __LINE__, (r))
-#define GRPC_SUBCHANNEL_REF_FROM_WEAK_REF(p, r) \
-  (p)->RefFromWeakRef(__FILE__, __LINE__, (r))
+#define GRPC_SUBCHANNEL_REF_FROM_WEAK_REF(p, r) (p)->RefFromWeakRef()
 #define GRPC_SUBCHANNEL_UNREF(p, r) (p)->Unref(__FILE__, __LINE__, (r))
 #define GRPC_SUBCHANNEL_WEAK_REF(p, r) (p)->WeakRef(__FILE__, __LINE__, (r))
 #define GRPC_SUBCHANNEL_WEAK_UNREF(p, r) (p)->WeakUnref(__FILE__, __LINE__, (r))
@@ -214,7 +213,7 @@ class Subchannel {
   // Attempts to return a strong ref when only the weak refcount is guaranteed
   // non-zero. If the strong refcount is zero, does not alter the refcount and
   // returns null.
-  Subchannel* RefFromWeakRef(GRPC_SUBCHANNEL_REF_EXTRA_ARGS);
+  Subchannel* RefFromWeakRef();
 
   // Gets the string representing the subchannel address.
   // Caller doesn't take ownership.
diff --git a/src/core/ext/filters/client_channel/xds/xds_client.cc b/src/core/ext/filters/client_channel/xds/xds_client.cc
index 7bb835071a6..bf04d21ed1d 100644
--- a/src/core/ext/filters/client_channel/xds/xds_client.cc
+++ b/src/core/ext/filters/client_channel/xds/xds_client.cc
@@ -639,7 +639,7 @@ void XdsClient::ChannelState::AdsCallState::OnResponseReceived(
 }
 
 void XdsClient::ChannelState::AdsCallState::OnResponseReceivedLocked(
-    void* arg, grpc_error* error) {
+    void* arg, grpc_error* /*error*/) {
   AdsCallState* ads_calld = static_cast<AdsCallState*>(arg);
   XdsClient* xds_client = ads_calld->xds_client();
   // Empty payload means the call was cancelled.
@@ -1083,7 +1083,7 @@ void XdsClient::ChannelState::LrsCallState::OnInitialRequestSent(
 }
 
 void XdsClient::ChannelState::LrsCallState::OnInitialRequestSentLocked(
-    void* arg, grpc_error* error) {
+    void* arg, grpc_error* /*error*/) {
   LrsCallState* lrs_calld = static_cast<LrsCallState*>(arg);
   // Clear the send_message_payload_.
   grpc_byte_buffer_destroy(lrs_calld->send_message_payload_);
@@ -1102,7 +1102,7 @@ void XdsClient::ChannelState::LrsCallState::OnResponseReceived(
 }
 
 void XdsClient::ChannelState::LrsCallState::OnResponseReceivedLocked(
-    void* arg, grpc_error* error) {
+    void* arg, grpc_error* /*error*/) {
   LrsCallState* lrs_calld = static_cast<LrsCallState*>(arg);
   XdsClient* xds_client = lrs_calld->xds_client();
   // Empty payload means the call was cancelled.
@@ -1286,17 +1286,17 @@ void XdsClient::Orphan() {
   Unref(DEBUG_LOCATION, "XdsClient::Orphan()");
 }
 
-void XdsClient::WatchClusterData(StringView cluster,
-                                 UniquePtr<ClusterWatcherInterface> watcher) {
+void XdsClient::WatchClusterData(
+    StringView /*cluster*/, UniquePtr<ClusterWatcherInterface> /*watcher*/) {
   // TODO(juanlishen): Implement.
 }
 
-void XdsClient::CancelClusterDataWatch(StringView cluster,
-                                       ClusterWatcherInterface* watcher) {
+void XdsClient::CancelClusterDataWatch(StringView /*cluster*/,
+                                       ClusterWatcherInterface* /*watcher*/) {
   // TODO(juanlishen): Implement.
 }
 
-void XdsClient::WatchEndpointData(StringView cluster,
+void XdsClient::WatchEndpointData(StringView /*cluster*/,
                                   UniquePtr<EndpointWatcherInterface> watcher) {
   EndpointWatcherInterface* w = watcher.get();
   cluster_state_.endpoint_watchers[w] = std::move(watcher);
@@ -1308,7 +1308,7 @@ void XdsClient::WatchEndpointData(StringView cluster,
   chand_->MaybeStartAdsCall();
 }
 
-void XdsClient::CancelEndpointDataWatch(StringView cluster,
+void XdsClient::CancelEndpointDataWatch(StringView /*cluster*/,
                                         EndpointWatcherInterface* watcher) {
   auto it = cluster_state_.endpoint_watchers.find(watcher);
   if (it != cluster_state_.endpoint_watchers.end()) {
@@ -1319,13 +1319,13 @@ void XdsClient::CancelEndpointDataWatch(StringView cluster,
   }
 }
 
-void XdsClient::AddClientStats(StringView cluster,
+void XdsClient::AddClientStats(StringView /*cluster*/,
                                XdsClientStats* client_stats) {
   cluster_state_.client_stats.insert(client_stats);
   chand_->MaybeStartLrsCall();
 }
 
-void XdsClient::RemoveClientStats(StringView cluster,
+void XdsClient::RemoveClientStats(StringView /*cluster*/,
                                   XdsClientStats* client_stats) {
   // TODO(roth): In principle, we should try to send a final load report
   // containing whatever final stats have been accumulated since the
diff --git a/src/core/ext/filters/client_idle/client_idle_filter.cc b/src/core/ext/filters/client_idle/client_idle_filter.cc
index afd6d949464..b8a5721f84c 100644
--- a/src/core/ext/filters/client_idle/client_idle_filter.cc
+++ b/src/core/ext/filters/client_idle/client_idle_filter.cc
@@ -283,7 +283,8 @@ void ChannelData::DecreaseCallCount() {
 }
 
 ChannelData::ChannelData(grpc_channel_element* elem,
-                         grpc_channel_element_args* args, grpc_error** error)
+                         grpc_channel_element_args* args,
+                         grpc_error** /*error*/)
     : elem_(elem),
       channel_stack_(args->channel_stack),
       client_idle_timeout_(GetClientIdleTimeout(args->channel_args)) {
@@ -352,7 +353,7 @@ void ChannelData::IdleTimerCallback(void* arg, grpc_error* error) {
 }
 
 void ChannelData::IdleTransportOpCompleteCallback(void* arg,
-                                                  grpc_error* error) {
+                                                  grpc_error* /*error*/) {
   ChannelData* chand = static_cast<ChannelData*>(arg);
   GRPC_CHANNEL_STACK_UNREF(chand->channel_stack_, "idle transport op");
 }
@@ -389,15 +390,15 @@ class CallData {
 };
 
 grpc_error* CallData::Init(grpc_call_element* elem,
-                           const grpc_call_element_args* args) {
+                           const grpc_call_element_args* /*args*/) {
   ChannelData* chand = static_cast<ChannelData*>(elem->channel_data);
   chand->IncreaseCallCount();
   return GRPC_ERROR_NONE;
 }
 
 void CallData::Destroy(grpc_call_element* elem,
-                       const grpc_call_final_info* final_info,
-                       grpc_closure* ignored) {
+                       const grpc_call_final_info* /*final_info*/,
+                       grpc_closure* /*ignored*/) {
   ChannelData* chand = static_cast<ChannelData*>(elem->channel_data);
   chand->DecreaseCallCount();
 }
@@ -416,7 +417,7 @@ const grpc_channel_filter grpc_client_idle_filter = {
     "client_idle"};
 
 static bool MaybeAddClientIdleFilter(grpc_channel_stack_builder* builder,
-                                     void* arg) {
+                                     void* /*arg*/) {
   const grpc_channel_args* channel_args =
       grpc_channel_stack_builder_get_channel_arguments(builder);
   if (!grpc_channel_args_want_minimal_stack(channel_args) &&
diff --git a/src/core/ext/filters/deadline/deadline_filter.cc b/src/core/ext/filters/deadline/deadline_filter.cc
index d6c2b8e2588..a99d9cb595b 100644
--- a/src/core/ext/filters/deadline/deadline_filter.cc
+++ b/src/core/ext/filters/deadline/deadline_filter.cc
@@ -38,7 +38,7 @@
 
 // The on_complete callback used when sending a cancel_error batch down the
 // filter stack.  Yields the call combiner when the batch returns.
-static void yield_call_combiner(void* arg, grpc_error* ignored) {
+static void yield_call_combiner(void* arg, grpc_error* /*ignored*/) {
   grpc_deadline_state* deadline_state = static_cast<grpc_deadline_state*>(arg);
   GRPC_CALL_COMBINER_STOP(deadline_state->call_combiner,
                           "got on_complete from cancel_stream batch");
@@ -233,14 +233,14 @@ void grpc_deadline_state_client_start_transport_stream_op_batch(
 //
 
 // Constructor for channel_data.  Used for both client and server filters.
-static grpc_error* deadline_init_channel_elem(grpc_channel_element* elem,
+static grpc_error* deadline_init_channel_elem(grpc_channel_element* /*elem*/,
                                               grpc_channel_element_args* args) {
   GPR_ASSERT(!args->is_last);
   return GRPC_ERROR_NONE;
 }
 
 // Destructor for channel_data.  Used for both client and server filters.
-static void deadline_destroy_channel_elem(grpc_channel_element* elem) {}
+static void deadline_destroy_channel_elem(grpc_channel_element* /*elem*/) {}
 
 // Call data used for both client and server filter.
 typedef struct base_call_data {
@@ -268,9 +268,9 @@ static grpc_error* deadline_init_call_elem(grpc_call_element* elem,
 }
 
 // Destructor for call_data.  Used for both client and server filters.
-static void deadline_destroy_call_elem(grpc_call_element* elem,
-                                       const grpc_call_final_info* final_info,
-                                       grpc_closure* ignored) {
+static void deadline_destroy_call_elem(
+    grpc_call_element* elem, const grpc_call_final_info* /*final_info*/,
+    grpc_closure* /*ignored*/) {
   grpc_deadline_state* deadline_state =
       static_cast<grpc_deadline_state*>(elem->call_data);
   deadline_state->~grpc_deadline_state();
diff --git a/src/core/ext/filters/http/client/http_client_filter.cc b/src/core/ext/filters/http/client/http_client_filter.cc
index 1687f7ead09..d0ad40ac82f 100644
--- a/src/core/ext/filters/http/client/http_client_filter.cc
+++ b/src/core/ext/filters/http/client/http_client_filter.cc
@@ -99,8 +99,7 @@ struct channel_data {
 };
 }  // namespace
 
-static grpc_error* client_filter_incoming_metadata(grpc_call_element* elem,
-                                                   grpc_metadata_batch* b) {
+static grpc_error* client_filter_incoming_metadata(grpc_metadata_batch* b) {
   if (b->idx.named.status != nullptr) {
     /* If both gRPC status and HTTP status are provided in the response, we
      * should prefer the gRPC status code, as mentioned in
@@ -177,7 +176,7 @@ static void recv_initial_metadata_ready(void* user_data, grpc_error* error) {
   grpc_call_element* elem = static_cast<grpc_call_element*>(user_data);
   call_data* calld = static_cast<call_data*>(elem->call_data);
   if (error == GRPC_ERROR_NONE) {
-    error = client_filter_incoming_metadata(elem, calld->recv_initial_metadata);
+    error = client_filter_incoming_metadata(calld->recv_initial_metadata);
     calld->recv_initial_metadata_error = GRPC_ERROR_REF(error);
   } else {
     GRPC_ERROR_REF(error);
@@ -204,8 +203,7 @@ static void recv_trailing_metadata_ready(void* user_data, grpc_error* error) {
     return;
   }
   if (error == GRPC_ERROR_NONE) {
-    error =
-        client_filter_incoming_metadata(elem, calld->recv_trailing_metadata);
+    error = client_filter_incoming_metadata(calld->recv_trailing_metadata);
   } else {
     GRPC_ERROR_REF(error);
   }
@@ -473,8 +471,8 @@ static grpc_error* http_client_init_call_elem(
 
 /* Destructor for call_data */
 static void http_client_destroy_call_elem(
-    grpc_call_element* elem, const grpc_call_final_info* final_info,
-    grpc_closure* ignored) {
+    grpc_call_element* elem, const grpc_call_final_info* /*final_info*/,
+    grpc_closure* /*ignored*/) {
   call_data* calld = static_cast<call_data*>(elem->call_data);
   calld->~call_data();
 }
diff --git a/src/core/ext/filters/http/client_authority_filter.cc b/src/core/ext/filters/http/client_authority_filter.cc
index 4d5d6233f8c..fd71c2fd845 100644
--- a/src/core/ext/filters/http/client_authority_filter.cc
+++ b/src/core/ext/filters/http/client_authority_filter.cc
@@ -80,9 +80,9 @@ grpc_error* client_authority_init_call_elem(
 }
 
 /* Destructor for call_data */
-void client_authority_destroy_call_elem(grpc_call_element* elem,
-                                        const grpc_call_final_info* final_info,
-                                        grpc_closure* ignored) {}
+void client_authority_destroy_call_elem(
+    grpc_call_element* /*elem*/, const grpc_call_final_info* /*final_info*/,
+    grpc_closure* /*ignored*/) {}
 
 /* Constructor for channel_data */
 grpc_error* client_authority_init_channel_elem(
diff --git a/src/core/ext/filters/http/message_compress/message_compress_filter.cc b/src/core/ext/filters/http/message_compress/message_compress_filter.cc
index 2f4854e43ec..f2b2ff34582 100644
--- a/src/core/ext/filters/http/message_compress/message_compress_filter.cc
+++ b/src/core/ext/filters/http/message_compress/message_compress_filter.cc
@@ -361,7 +361,7 @@ static void on_send_message_next_done(void* arg, grpc_error* error) {
   }
 }
 
-static void start_send_message_batch(void* arg, grpc_error* unused) {
+static void start_send_message_batch(void* arg, grpc_error* /*unused*/) {
   grpc_call_element* elem = static_cast<grpc_call_element*>(arg);
   if (skip_message_compression(elem)) {
     send_message_batch_continue(elem);
@@ -448,9 +448,9 @@ static grpc_error* compress_init_call_elem(grpc_call_element* elem,
 }
 
 /* Destructor for call_data */
-static void compress_destroy_call_elem(grpc_call_element* elem,
-                                       const grpc_call_final_info* final_info,
-                                       grpc_closure* ignored) {
+static void compress_destroy_call_elem(
+    grpc_call_element* elem, const grpc_call_final_info* /*final_info*/,
+    grpc_closure* /*ignored*/) {
   call_data* calld = static_cast<call_data*>(elem->call_data);
   calld->~call_data();
 }
@@ -487,7 +487,7 @@ static grpc_error* compress_init_channel_elem(grpc_channel_element* elem,
 }
 
 /* Destructor for channel data */
-static void compress_destroy_channel_elem(grpc_channel_element* elem) {}
+static void compress_destroy_channel_elem(grpc_channel_element* /*elem*/) {}
 
 const grpc_channel_filter grpc_message_compress_filter = {
     compress_start_transport_stream_op_batch,
diff --git a/src/core/ext/filters/http/server/http_server_filter.cc b/src/core/ext/filters/http/server/http_server_filter.cc
index 99f6b65e424..905f2ebc55d 100644
--- a/src/core/ext/filters/http/server/http_server_filter.cc
+++ b/src/core/ext/filters/http/server/http_server_filter.cc
@@ -99,8 +99,7 @@ struct channel_data {
 
 }  // namespace
 
-static grpc_error* hs_filter_outgoing_metadata(grpc_call_element* elem,
-                                               grpc_metadata_batch* b) {
+static grpc_error* hs_filter_outgoing_metadata(grpc_metadata_batch* b) {
   if (b->idx.named.grpc_message != nullptr) {
     grpc_slice pct_encoded_msg = grpc_percent_encode_slice(
         GRPC_MDVALUE(b->idx.named.grpc_message->md),
@@ -427,10 +426,9 @@ static grpc_error* hs_mutate_op(grpc_call_element* elem,
                      &calld->content_type,
                      GRPC_MDELEM_CONTENT_TYPE_APPLICATION_SLASH_GRPC,
                      GRPC_BATCH_CONTENT_TYPE));
-    hs_add_error(
-        error_name, &error,
-        hs_filter_outgoing_metadata(
-            elem, op->payload->send_initial_metadata.send_initial_metadata));
+    hs_add_error(error_name, &error,
+                 hs_filter_outgoing_metadata(
+                     op->payload->send_initial_metadata.send_initial_metadata));
     if (error != GRPC_ERROR_NONE) return error;
   }
 
@@ -463,7 +461,7 @@ static grpc_error* hs_mutate_op(grpc_call_element* elem,
 
   if (op->send_trailing_metadata) {
     grpc_error* error = hs_filter_outgoing_metadata(
-        elem, op->payload->send_trailing_metadata.send_trailing_metadata);
+        op->payload->send_trailing_metadata.send_trailing_metadata);
     if (error != GRPC_ERROR_NONE) return error;
   }
 
@@ -492,8 +490,8 @@ static grpc_error* hs_init_call_elem(grpc_call_element* elem,
 
 /* Destructor for call_data */
 static void hs_destroy_call_elem(grpc_call_element* elem,
-                                 const grpc_call_final_info* final_info,
-                                 grpc_closure* ignored) {
+                                 const grpc_call_final_info* /*final_info*/,
+                                 grpc_closure* /*ignored*/) {
   call_data* calld = static_cast<call_data*>(elem->call_data);
   calld->~call_data();
 }
@@ -511,7 +509,7 @@ static grpc_error* hs_init_channel_elem(grpc_channel_element* elem,
 }
 
 /* Destructor for channel data */
-static void hs_destroy_channel_elem(grpc_channel_element* elem) {}
+static void hs_destroy_channel_elem(grpc_channel_element* /*elem*/) {}
 
 const grpc_channel_filter grpc_http_server_filter = {
     hs_start_transport_stream_op_batch,
diff --git a/src/core/ext/filters/max_age/max_age_filter.cc b/src/core/ext/filters/max_age/max_age_filter.cc
index 982fabca833..c95c687d103 100644
--- a/src/core/ext/filters/max_age/max_age_filter.cc
+++ b/src/core/ext/filters/max_age/max_age_filter.cc
@@ -206,7 +206,7 @@ static void decrease_call_count(channel_data* chand) {
   }
 }
 
-static void start_max_idle_timer_after_init(void* arg, grpc_error* error) {
+static void start_max_idle_timer_after_init(void* arg, grpc_error* /*error*/) {
   channel_data* chand = static_cast<channel_data*>(arg);
   /* Decrease call_count. If there are no active calls at this time,
      max_idle_timer will start here. If the number of active calls is not 0,
@@ -257,7 +257,7 @@ class ConnectivityWatcher : public AsyncConnectivityStateWatcherInterface {
 
 }  // namespace grpc_core
 
-static void start_max_age_timer_after_init(void* arg, grpc_error* error) {
+static void start_max_age_timer_after_init(void* arg, grpc_error* /*error*/) {
   channel_data* chand = static_cast<channel_data*>(arg);
   gpr_mu_lock(&chand->max_age_timer_mu);
   chand->max_age_timer_pending = true;
@@ -276,7 +276,7 @@ static void start_max_age_timer_after_init(void* arg, grpc_error* error) {
 }
 
 static void start_max_age_grace_timer_after_goaway_op(void* arg,
-                                                      grpc_error* error) {
+                                                      grpc_error* /*error*/) {
   channel_data* chand = static_cast<channel_data*>(arg);
   gpr_mu_lock(&chand->max_age_timer_mu);
   chand->max_age_grace_timer_pending = true;
@@ -407,17 +407,17 @@ add_random_max_connection_age_jitter_and_convert_to_grpc_millis(int value) {
 }
 
 /* Constructor for call_data. */
-static grpc_error* max_age_init_call_elem(grpc_call_element* elem,
-                                          const grpc_call_element_args* args) {
+static grpc_error* max_age_init_call_elem(
+    grpc_call_element* elem, const grpc_call_element_args* /*args*/) {
   channel_data* chand = static_cast<channel_data*>(elem->channel_data);
   increase_call_count(chand);
   return GRPC_ERROR_NONE;
 }
 
 /* Destructor for call_data. */
-static void max_age_destroy_call_elem(grpc_call_element* elem,
-                                      const grpc_call_final_info* final_info,
-                                      grpc_closure* ignored) {
+static void max_age_destroy_call_elem(
+    grpc_call_element* elem, const grpc_call_final_info* /*final_info*/,
+    grpc_closure* /*ignored*/) {
   channel_data* chand = static_cast<channel_data*>(elem->channel_data);
   decrease_call_count(chand);
 }
@@ -527,7 +527,7 @@ const grpc_channel_filter grpc_max_age_filter = {
     "max_age"};
 
 static bool maybe_add_max_age_filter(grpc_channel_stack_builder* builder,
-                                     void* arg) {
+                                     void* /*arg*/) {
   const grpc_channel_args* channel_args =
       grpc_channel_stack_builder_get_channel_arguments(builder);
   bool enable =