Merge branch 'master' into fix_reuseport

31 files changed, 61 insertions, 1118 deletions

diff --git a/src/core/ext/filters/client_channel/client_channel.cc b/src/core/ext/filters/client_channel/client_channel.cc
index bf3911e5ee..bbc5160bec 100644
--- a/src/core/ext/filters/client_channel/client_channel.cc
+++ b/src/core/ext/filters/client_channel/client_channel.cc
@@ -38,12 +38,12 @@
 #include "src/core/ext/filters/client_channel/proxy_mapper_registry.h"
 #include "src/core/ext/filters/client_channel/resolver_registry.h"
 #include "src/core/ext/filters/client_channel/retry_throttle.h"
+#include "src/core/ext/filters/client_channel/status_util.h"
 #include "src/core/ext/filters/client_channel/subchannel.h"
 #include "src/core/ext/filters/deadline/deadline_filter.h"
 #include "src/core/lib/backoff/backoff.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/connected_channel.h"
-#include "src/core/lib/channel/status_util.h"
 #include "src/core/lib/gpr/string.h"
 #include "src/core/lib/gprpp/inlined_vector.h"
 #include "src/core/lib/gprpp/manual_constructor.h"
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
index 47e1deef12..e805593dd8 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
@@ -423,13 +423,13 @@ void ParseServer(const grpc_grpclb_server* server,
    * server->ip_address.bytes. */
   const grpc_grpclb_ip_address* ip = &server->ip_address;
   if (ip->size == 4) {
-    addr->len = sizeof(grpc_sockaddr_in);
+    addr->len = static_cast<socklen_t>(sizeof(grpc_sockaddr_in));
     grpc_sockaddr_in* addr4 = reinterpret_cast<grpc_sockaddr_in*>(&addr->addr);
     addr4->sin_family = GRPC_AF_INET;
     memcpy(&addr4->sin_addr, ip->bytes, ip->size);
     addr4->sin_port = netorder_port;
   } else if (ip->size == 16) {
-    addr->len = sizeof(grpc_sockaddr_in6);
+    addr->len = static_cast<socklen_t>(sizeof(grpc_sockaddr_in6));
     grpc_sockaddr_in6* addr6 = (grpc_sockaddr_in6*)&addr->addr;
     addr6->sin6_family = GRPC_AF_INET6;
     memcpy(&addr6->sin6_addr, ip->bytes, ip->size);
diff --git a/src/core/ext/filters/client_channel/lb_policy_factory.cc b/src/core/ext/filters/client_channel/lb_policy_factory.cc
index 80646a10cc..7c8cba55b7 100644
--- a/src/core/ext/filters/client_channel/lb_policy_factory.cc
+++ b/src/core/ext/filters/client_channel/lb_policy_factory.cc
@@ -66,7 +66,7 @@ void grpc_lb_addresses_set_address(grpc_lb_addresses* addresses, size_t index,
   if (user_data != nullptr) GPR_ASSERT(addresses->user_data_vtable != nullptr);
   grpc_lb_address* target = &addresses->addresses[index];
   memcpy(target->address.addr, address, address_len);
-  target->address.len = address_len;
+  target->address.len = static_cast<socklen_t>(address_len);
   target->is_balancer = is_balancer;
   target->balancer_name = gpr_strdup(balancer_name);
   target->user_data = user_data;
diff --git a/src/core/ext/filters/client_channel/method_params.cc b/src/core/ext/filters/client_channel/method_params.cc
index 1f116bb67d..374b87e170 100644
--- a/src/core/ext/filters/client_channel/method_params.cc
+++ b/src/core/ext/filters/client_channel/method_params.cc
@@ -26,7 +26,7 @@
 #include <grpc/support/string_util.h>
 
 #include "src/core/ext/filters/client_channel/method_params.h"
-#include "src/core/lib/channel/status_util.h"
+#include "src/core/ext/filters/client_channel/status_util.h"
 #include "src/core/lib/gpr/string.h"
 #include "src/core/lib/gprpp/memory.h"
 
diff --git a/src/core/ext/filters/client_channel/method_params.h b/src/core/ext/filters/client_channel/method_params.h
index 099924edf3..48ece29867 100644
--- a/src/core/ext/filters/client_channel/method_params.h
+++ b/src/core/ext/filters/client_channel/method_params.h
@@ -21,7 +21,7 @@
 
 #include <grpc/support/port_platform.h>
 
-#include "src/core/lib/channel/status_util.h"
+#include "src/core/ext/filters/client_channel/status_util.h"
 #include "src/core/lib/gprpp/ref_counted.h"
 #include "src/core/lib/gprpp/ref_counted_ptr.h"
 #include "src/core/lib/iomgr/exec_ctx.h"  // for grpc_millis
diff --git a/src/core/ext/filters/client_channel/parse_address.cc b/src/core/ext/filters/client_channel/parse_address.cc
index 92ea259cf0..b3900114ad 100644
--- a/src/core/ext/filters/client_channel/parse_address.cc
+++ b/src/core/ext/filters/client_channel/parse_address.cc
@@ -50,7 +50,7 @@ bool grpc_parse_unix(const grpc_uri* uri,
   if (path_len == maxlen) return false;
   un->sun_family = AF_UNIX;
   strcpy(un->sun_path, uri->path);
-  resolved_addr->len = sizeof(*un);
+  resolved_addr->len = static_cast<socklen_t>(sizeof(*un));
   return true;
 }
 
@@ -72,7 +72,7 @@ bool grpc_parse_ipv4_hostport(const char* hostport, grpc_resolved_address* addr,
   if (!gpr_split_host_port(hostport, &host, &port)) return false;
   // Parse IP address.
   memset(addr, 0, sizeof(*addr));
-  addr->len = sizeof(grpc_sockaddr_in);
+  addr->len = static_cast<socklen_t>(sizeof(grpc_sockaddr_in));
   grpc_sockaddr_in* in = reinterpret_cast<grpc_sockaddr_in*>(addr->addr);
   in->sin_family = GRPC_AF_INET;
   if (grpc_inet_pton(GRPC_AF_INET, host, &in->sin_addr) == 0) {
@@ -118,7 +118,7 @@ bool grpc_parse_ipv6_hostport(const char* hostport, grpc_resolved_address* addr,
   if (!gpr_split_host_port(hostport, &host, &port)) return false;
   // Parse IP address.
   memset(addr, 0, sizeof(*addr));
-  addr->len = sizeof(grpc_sockaddr_in6);
+  addr->len = static_cast<socklen_t>(sizeof(grpc_sockaddr_in6));
   grpc_sockaddr_in6* in6 = reinterpret_cast<grpc_sockaddr_in6*>(addr->addr);
   in6->sin6_family = GRPC_AF_INET6;
   // Handle the RFC6874 syntax for IPv6 zone identifiers.
diff --git a/src/core/lib/channel/status_util.cc b/src/core/ext/filters/client_channel/status_util.cc
index 563db40846..11f732ab44 100644
--- a/src/core/lib/channel/status_util.cc
+++ b/src/core/ext/filters/client_channel/status_util.cc
@@ -18,7 +18,7 @@
 
 #include <grpc/support/port_platform.h>
 
-#include "src/core/lib/channel/status_util.h"
+#include "src/core/ext/filters/client_channel/status_util.h"
 
 #include "src/core/lib/gpr/useful.h"
 
diff --git a/src/core/lib/channel/status_util.h b/src/core/ext/filters/client_channel/status_util.h
index 5409de6b3c..e018709730 100644
--- a/src/core/lib/channel/status_util.h
+++ b/src/core/ext/filters/client_channel/status_util.h
@@ -16,8 +16,8 @@
  *
  */
 
-#ifndef GRPC_CORE_LIB_CHANNEL_STATUS_UTIL_H
-#define GRPC_CORE_LIB_CHANNEL_STATUS_UTIL_H
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_STATUS_UTIL_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_STATUS_UTIL_H
 
 #include <grpc/support/port_platform.h>
 
@@ -55,4 +55,4 @@ class StatusCodeSet {
 }  // namespace internal
 }  // namespace grpc_core
 
-#endif /* GRPC_CORE_LIB_CHANNEL_STATUS_UTIL_H */
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_STATUS_UTIL_H */
diff --git a/src/core/ext/filters/client_channel/subchannel.cc b/src/core/ext/filters/client_channel/subchannel.cc
index d7815fb7e1..cae7cc35e3 100644
--- a/src/core/ext/filters/client_channel/subchannel.cc
+++ b/src/core/ext/filters/client_channel/subchannel.cc
@@ -40,7 +40,6 @@
 #include "src/core/lib/debug/stats.h"
 #include "src/core/lib/gprpp/debug_location.h"
 #include "src/core/lib/gprpp/manual_constructor.h"
-#include "src/core/lib/gprpp/ref_counted_ptr.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/profiling/timers.h"
diff --git a/src/core/lib/channel/channel_trace.cc b/src/core/lib/channel/channel_trace.cc
deleted file mode 100644
index 67d5fd364b..0000000000
--- a/src/core/lib/channel/channel_trace.cc
+++ /dev/null
@@ -1,238 +0,0 @@
-/*
- *
- * Copyright 2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-#include <grpc/impl/codegen/port_platform.h>
-
-#include "src/core/lib/channel/channel_trace.h"
-
-#include <grpc/grpc.h>
-#include <grpc/support/alloc.h>
-#include <grpc/support/log.h>
-#include <grpc/support/string_util.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "src/core/lib/channel/channel_trace_registry.h"
-#include "src/core/lib/channel/status_util.h"
-#include "src/core/lib/gpr/string.h"
-#include "src/core/lib/gpr/useful.h"
-#include "src/core/lib/gprpp/memory.h"
-#include "src/core/lib/iomgr/error.h"
-#include "src/core/lib/slice/slice_internal.h"
-#include "src/core/lib/surface/channel.h"
-#include "src/core/lib/transport/connectivity_state.h"
-#include "src/core/lib/transport/error_utils.h"
-
-namespace grpc_core {
-
-ChannelTrace::TraceEvent::TraceEvent(
-    Severity severity, grpc_slice data,
-    RefCountedPtr<ChannelTrace> referenced_tracer, ReferencedType type)
-    : severity_(severity),
-      data_(data),
-      timestamp_(grpc_millis_to_timespec(grpc_core::ExecCtx::Get()->Now(),
-                                         GPR_CLOCK_REALTIME)),
-      next_(nullptr),
-      referenced_tracer_(std::move(referenced_tracer)),
-      referenced_type_(type) {}
-
-ChannelTrace::TraceEvent::TraceEvent(Severity severity, grpc_slice data)
-    : severity_(severity),
-      data_(data),
-      timestamp_(grpc_millis_to_timespec(grpc_core::ExecCtx::Get()->Now(),
-                                         GPR_CLOCK_REALTIME)),
-      next_(nullptr) {}
-
-ChannelTrace::TraceEvent::~TraceEvent() { grpc_slice_unref_internal(data_); }
-
-ChannelTrace::ChannelTrace(size_t max_events)
-    : channel_uuid_(-1),
-      num_events_logged_(0),
-      list_size_(0),
-      max_list_size_(max_events),
-      head_trace_(nullptr),
-      tail_trace_(nullptr) {
-  if (max_list_size_ == 0) return;  // tracing is disabled if max_events == 0
-  gpr_mu_init(&tracer_mu_);
-  channel_uuid_ = grpc_channel_trace_registry_register_channel_trace(this);
-  time_created_ = grpc_millis_to_timespec(grpc_core::ExecCtx::Get()->Now(),
-                                          GPR_CLOCK_REALTIME);
-}
-
-ChannelTrace::~ChannelTrace() {
-  if (max_list_size_ == 0) return;  // tracing is disabled if max_events == 0
-  TraceEvent* it = head_trace_;
-  while (it != nullptr) {
-    TraceEvent* to_free = it;
-    it = it->next();
-    Delete<TraceEvent>(to_free);
-  }
-  grpc_channel_trace_registry_unregister_channel_trace(channel_uuid_);
-  gpr_mu_destroy(&tracer_mu_);
-}
-
-intptr_t ChannelTrace::GetUuid() const { return channel_uuid_; }
-
-void ChannelTrace::AddTraceEventHelper(TraceEvent* new_trace_event) {
-  ++num_events_logged_;
-  // first event case
-  if (head_trace_ == nullptr) {
-    head_trace_ = tail_trace_ = new_trace_event;
-  }
-  // regular event add case
-  else {
-    tail_trace_->set_next(new_trace_event);
-    tail_trace_ = tail_trace_->next();
-  }
-  ++list_size_;
-  // maybe garbage collect the end
-  if (list_size_ > max_list_size_) {
-    TraceEvent* to_free = head_trace_;
-    head_trace_ = head_trace_->next();
-    Delete<TraceEvent>(to_free);
-    --list_size_;
-  }
-}
-
-void ChannelTrace::AddTraceEvent(Severity severity, grpc_slice data) {
-  if (max_list_size_ == 0) return;  // tracing is disabled if max_events == 0
-  AddTraceEventHelper(New<TraceEvent>(severity, data));
-}
-
-void ChannelTrace::AddTraceEventReferencingChannel(
-    Severity severity, grpc_slice data,
-    RefCountedPtr<ChannelTrace> referenced_tracer) {
-  if (max_list_size_ == 0) return;  // tracing is disabled if max_events == 0
-  // create and fill up the new event
-  AddTraceEventHelper(
-      New<TraceEvent>(severity, data, std::move(referenced_tracer), Channel));
-}
-
-void ChannelTrace::AddTraceEventReferencingSubchannel(
-    Severity severity, grpc_slice data,
-    RefCountedPtr<ChannelTrace> referenced_tracer) {
-  if (max_list_size_ == 0) return;  // tracing is disabled if max_events == 0
-  // create and fill up the new event
-  AddTraceEventHelper(New<TraceEvent>(
-      severity, data, std::move(referenced_tracer), Subchannel));
-}
-
-namespace {
-
-// returns an allocated string that represents tm according to RFC-3339, and,
-// more specifically, follows:
-// https://developers.google.com/protocol-buffers/docs/proto3#json
-//
-// "Uses RFC 3339, where generated output will always be Z-normalized and uses
-// 0, 3, 6 or 9 fractional digits."
-char* fmt_time(gpr_timespec tm) {
-  char time_buffer[35];
-  char ns_buffer[11];  // '.' + 9 digits of precision
-  struct tm* tm_info = localtime((const time_t*)&tm.tv_sec);
-  strftime(time_buffer, sizeof(time_buffer), "%Y-%m-%dT%H:%M:%S", tm_info);
-  snprintf(ns_buffer, 11, ".%09d", tm.tv_nsec);
-  // This loop trims off trailing zeros by inserting a null character that the
-  // right point. We iterate in chunks of three because we want 0, 3, 6, or 9
-  // fractional digits.
-  for (int i = 7; i >= 1; i -= 3) {
-    if (ns_buffer[i] == '0' && ns_buffer[i + 1] == '0' &&
-        ns_buffer[i + 2] == '0') {
-      ns_buffer[i] = '\0';
-      // Edge case in which all fractional digits were 0.
-      if (i == 1) {
-        ns_buffer[0] = '\0';
-      }
-    } else {
-      break;
-    }
-  }
-  char* full_time_str;
-  gpr_asprintf(&full_time_str, "%s%sZ", time_buffer, ns_buffer);
-  return full_time_str;
-}
-
-const char* severity_string(ChannelTrace::Severity severity) {
-  switch (severity) {
-    case ChannelTrace::Severity::Info:
-      return "CT_INFO";
-    case ChannelTrace::Severity::Warning:
-      return "CT_WARNING";
-    case ChannelTrace::Severity::Error:
-      return "CT_ERROR";
-    default:
-      GPR_UNREACHABLE_CODE(return "CT_UNKNOWN");
-  }
-}
-
-}  // anonymous namespace
-
-void ChannelTrace::TraceEvent::RenderTraceEvent(grpc_json* json) const {
-  grpc_json* json_iterator = nullptr;
-  json_iterator = grpc_json_create_child(json_iterator, json, "description",
-                                         grpc_slice_to_c_string(data_),
-                                         GRPC_JSON_STRING, true);
-  json_iterator = grpc_json_create_child(json_iterator, json, "severity",
-                                         severity_string(severity_),
-                                         GRPC_JSON_STRING, false);
-  json_iterator =
-      grpc_json_create_child(json_iterator, json, "timestamp",
-                             fmt_time(timestamp_), GRPC_JSON_STRING, true);
-  if (referenced_tracer_ != nullptr) {
-    char* uuid_str;
-    gpr_asprintf(&uuid_str, "%" PRIdPTR, referenced_tracer_->channel_uuid_);
-    grpc_json* child_ref = grpc_json_create_child(
-        json_iterator, json,
-        (referenced_type_ == Channel) ? "channelRef" : "subchannelRef", nullptr,
-        GRPC_JSON_OBJECT, false);
-    json_iterator = grpc_json_create_child(
-        nullptr, child_ref,
-        (referenced_type_ == Channel) ? "channelId" : "subchannelId", uuid_str,
-        GRPC_JSON_STRING, true);
-    json_iterator = child_ref;
-  }
-}
-
-char* ChannelTrace::RenderTrace() const {
-  if (!max_list_size_)
-    return nullptr;  // tracing is disabled if max_events == 0
-  grpc_json* json = grpc_json_create(GRPC_JSON_OBJECT);
-  char* num_events_logged_str;
-  gpr_asprintf(&num_events_logged_str, "%" PRId64, num_events_logged_);
-  grpc_json* json_iterator = nullptr;
-  json_iterator =
-      grpc_json_create_child(json_iterator, json, "numEventsLogged",
-                             num_events_logged_str, GRPC_JSON_STRING, true);
-  json_iterator =
-      grpc_json_create_child(json_iterator, json, "creationTime",
-                             fmt_time(time_created_), GRPC_JSON_STRING, true);
-  grpc_json* events = grpc_json_create_child(json_iterator, json, "events",
-                                             nullptr, GRPC_JSON_ARRAY, false);
-  json_iterator = nullptr;
-  TraceEvent* it = head_trace_;
-  while (it != nullptr) {
-    json_iterator = grpc_json_create_child(json_iterator, events, nullptr,
-                                           nullptr, GRPC_JSON_OBJECT, false);
-    it->RenderTraceEvent(json_iterator);
-    it = it->next();
-  }
-  char* json_str = grpc_json_dump_to_string(json, 0);
-  grpc_json_destroy(json);
-  return json_str;
-}
-
-}  // namespace grpc_core
diff --git a/src/core/lib/channel/channel_trace.h b/src/core/lib/channel/channel_trace.h
deleted file mode 100644
index 1df1e585f2..0000000000
--- a/src/core/lib/channel/channel_trace.h
+++ /dev/null
@@ -1,133 +0,0 @@
-/*
- *
- * Copyright 2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-#ifndef GRPC_CORE_LIB_CHANNEL_CHANNEL_TRACE_H
-#define GRPC_CORE_LIB_CHANNEL_CHANNEL_TRACE_H
-
-#include <grpc/impl/codegen/port_platform.h>
-
-#include <grpc/grpc.h>
-#include "src/core/lib/gprpp/ref_counted.h"
-#include "src/core/lib/gprpp/ref_counted_ptr.h"
-#include "src/core/lib/iomgr/error.h"
-#include "src/core/lib/json/json.h"
-
-namespace grpc_core {
-
-// Object used to hold live data for a channel. This data is exposed via the
-// channelz service:
-// https://github.com/grpc/proposal/blob/master/A14-channelz.md
-class ChannelTrace : public RefCounted<ChannelTrace> {
- public:
-  ChannelTrace(size_t max_events);
-  ~ChannelTrace();
-
-  // returns the tracer's uuid
-  intptr_t GetUuid() const;
-
-  enum Severity {
-    Unset = 0,  // never to be used
-    Info,       // we start at 1 to avoid using proto default values
-    Warning,
-    Error
-  };
-
-  // Adds a new trace event to the tracing object
-  //
-  // TODO(ncteisen): as this call is used more and more throughout the gRPC
-  // stack, determine if it makes more sense to accept a char* instead of a
-  // slice.
-  void AddTraceEvent(Severity severity, grpc_slice data);
-
-  // Adds a new trace event to the tracing object. This trace event refers to a
-  // an event on a child of the channel. For example, if this channel has
-  // created a new subchannel, then it would record that with a TraceEvent
-  // referencing the new subchannel.
-  //
-  // TODO(ncteisen): Once channelz is implemented, the events should reference
-  // the overall channelz object, not just the ChannelTrace object.
-  // TODO(ncteisen): as this call is used more and more throughout the gRPC
-  // stack, determine if it makes more sense to accept a char* instead of a
-  // slice.
-  void AddTraceEventReferencingChannel(
-      Severity severity, grpc_slice data,
-      RefCountedPtr<ChannelTrace> referenced_tracer);
-  void AddTraceEventReferencingSubchannel(
-      Severity severity, grpc_slice data,
-      RefCountedPtr<ChannelTrace> referenced_tracer);
-
-  // Returns the tracing data rendered as a grpc json string.
-  // The string is owned by the caller and must be freed.
-  char* RenderTrace() const;
-
- private:
-  // Types of objects that can be references by trace events.
-  enum ReferencedType { Channel, Subchannel };
-  // Private class to encapsulate all the data and bookkeeping needed for a
-  // a trace event.
-  class TraceEvent {
-   public:
-    // Constructor for a TraceEvent that references a different channel.
-    // TODO(ncteisen): once channelz is implemented, this should reference the
-    // overall channelz object, not just the ChannelTrace object
-    TraceEvent(Severity severity, grpc_slice data,
-               RefCountedPtr<ChannelTrace> referenced_tracer,
-               ReferencedType type);
-
-    // Constructor for a TraceEvent that does not reverence a different
-    // channel.
-    TraceEvent(Severity severity, grpc_slice data);
-
-    ~TraceEvent();
-
-    // Renders the data inside of this TraceEvent into a json object. This is
-    // used by the ChannelTrace, when it is rendering itself.
-    void RenderTraceEvent(grpc_json* json) const;
-
-    // set and get for the next_ pointer.
-    TraceEvent* next() const { return next_; }
-    void set_next(TraceEvent* next) { next_ = next; }
-
-   private:
-    Severity severity_;
-    grpc_slice data_;
-    gpr_timespec timestamp_;
-    TraceEvent* next_;
-    // the tracer object for the (sub)channel that this trace event refers to.
-    RefCountedPtr<ChannelTrace> referenced_tracer_;
-    // the type that the referenced tracer points to. Unused if this trace
-    // does not point to any channel or subchannel
-    ReferencedType referenced_type_;
-  };  // TraceEvent
-
-  // Internal helper to add and link in a trace event
-  void AddTraceEventHelper(TraceEvent* new_trace_event);
-
-  gpr_mu tracer_mu_;
-  intptr_t channel_uuid_;
-  uint64_t num_events_logged_;
-  size_t list_size_;
-  size_t max_list_size_;
-  TraceEvent* head_trace_;
-  TraceEvent* tail_trace_;
-  gpr_timespec time_created_;
-};
-
-}  // namespace grpc_core
-
-#endif /* GRPC_CORE_LIB_CHANNEL_CHANNEL_TRACE_H */
diff --git a/src/core/lib/channel/channel_trace_registry.cc b/src/core/lib/channel/channel_trace_registry.cc
deleted file mode 100644
index 6c82431467..0000000000
--- a/src/core/lib/channel/channel_trace_registry.cc
+++ /dev/null
@@ -1,80 +0,0 @@
-/*
- *
- * Copyright 2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-#include <grpc/impl/codegen/port_platform.h>
-
-#include "src/core/lib/avl/avl.h"
-#include "src/core/lib/channel/channel_trace.h"
-#include "src/core/lib/channel/channel_trace_registry.h"
-#include "src/core/lib/gpr/useful.h"
-
-#include <grpc/support/alloc.h>
-#include <grpc/support/log.h>
-
-// file global lock and avl.
-static gpr_mu g_mu;
-static grpc_avl g_avl;
-static gpr_atm g_uuid = 0;
-
-// avl vtable for uuid (intptr_t) -> ChannelTrace
-// this table is only looking, it does not own anything.
-static void destroy_intptr(void* not_used, void* user_data) {}
-static void* copy_intptr(void* key, void* user_data) { return key; }
-static long compare_intptr(void* key1, void* key2, void* user_data) {
-  return GPR_ICMP(key1, key2);
-}
-
-static void destroy_channel_trace(void* trace, void* user_data) {}
-static void* copy_channel_trace(void* trace, void* user_data) { return trace; }
-static const grpc_avl_vtable avl_vtable = {
-    destroy_intptr, copy_intptr, compare_intptr, destroy_channel_trace,
-    copy_channel_trace};
-
-void grpc_channel_trace_registry_init() {
-  gpr_mu_init(&g_mu);
-  g_avl = grpc_avl_create(&avl_vtable);
-}
-
-void grpc_channel_trace_registry_shutdown() {
-  grpc_avl_unref(g_avl, nullptr);
-  gpr_mu_destroy(&g_mu);
-}
-
-intptr_t grpc_channel_trace_registry_register_channel_trace(
-    grpc_core::ChannelTrace* channel_trace) {
-  intptr_t prior = gpr_atm_no_barrier_fetch_add(&g_uuid, 1);
-  gpr_mu_lock(&g_mu);
-  g_avl = grpc_avl_add(g_avl, (void*)prior, channel_trace, nullptr);
-  gpr_mu_unlock(&g_mu);
-  return prior;
-}
-
-void grpc_channel_trace_registry_unregister_channel_trace(intptr_t uuid) {
-  gpr_mu_lock(&g_mu);
-  g_avl = grpc_avl_remove(g_avl, (void*)uuid, nullptr);
-  gpr_mu_unlock(&g_mu);
-}
-
-grpc_core::ChannelTrace* grpc_channel_trace_registry_get_channel_trace(
-    intptr_t uuid) {
-  gpr_mu_lock(&g_mu);
-  grpc_core::ChannelTrace* ret = static_cast<grpc_core::ChannelTrace*>(
-      grpc_avl_get(g_avl, (void*)uuid, nullptr));
-  gpr_mu_unlock(&g_mu);
-  return ret;
-}
diff --git a/src/core/lib/channel/channel_trace_registry.h b/src/core/lib/channel/channel_trace_registry.h
deleted file mode 100644
index 391ecba7de..0000000000
--- a/src/core/lib/channel/channel_trace_registry.h
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- *
- * Copyright 2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-#ifndef GRPC_CORE_LIB_CHANNEL_CHANNEL_TRACE_REGISTRY_H
-#define GRPC_CORE_LIB_CHANNEL_CHANNEL_TRACE_REGISTRY_H
-
-#include <grpc/impl/codegen/port_platform.h>
-
-#include "src/core/lib/channel/channel_trace.h"
-
-#include <stdint.h>
-
-// TODO(ncteisen): convert this file to C++
-
-void grpc_channel_trace_registry_init();
-void grpc_channel_trace_registry_shutdown();
-
-// globally registers a ChannelTrace. Returns its unique uuid
-intptr_t grpc_channel_trace_registry_register_channel_trace(
-    grpc_core::ChannelTrace* channel_trace);
-// globally unregisters the ChannelTrace that is associated to uuid.
-void grpc_channel_trace_registry_unregister_channel_trace(intptr_t uuid);
-// if object with uuid has previously been registered, returns the ChannelTrace
-// associated with that uuid. Else returns nullptr.
-grpc_core::ChannelTrace* grpc_channel_trace_registry_get_channel_trace(
-    intptr_t uuid);
-
-#endif /* GRPC_CORE_LIB_CHANNEL_CHANNEL_TRACE_REGISTRY_H */
diff --git a/src/core/lib/iomgr/resolve_address.h b/src/core/lib/iomgr/resolve_address.h
index 68cdefcf03..fe0d834582 100644
--- a/src/core/lib/iomgr/resolve_address.h
+++ b/src/core/lib/iomgr/resolve_address.h
@@ -22,13 +22,28 @@
 #include <grpc/support/port_platform.h>
 
 #include <stddef.h>
+
+#include "src/core/lib/iomgr/port.h"
+
+#ifdef GRPC_UV
+#include <uv.h>
+#endif
+
+#ifdef GRPC_WINSOCK_SOCKET
+#include <ws2tcpip.h>
+#endif
+
+#ifdef GRPC_POSIX_SOCKET
+#include <sys/socket.h>
+#endif
+
 #include "src/core/lib/iomgr/pollset_set.h"
 
 #define GRPC_MAX_SOCKADDR_SIZE 128
 
 typedef struct {
   char addr[GRPC_MAX_SOCKADDR_SIZE];
-  size_t len;
+  socklen_t len;
 } grpc_resolved_address;
 
 typedef struct {
diff --git a/src/core/lib/iomgr/sockaddr_utils.cc b/src/core/lib/iomgr/sockaddr_utils.cc
index bc3550a679..df25f7778a 100644
--- a/src/core/lib/iomgr/sockaddr_utils.cc
+++ b/src/core/lib/iomgr/sockaddr_utils.cc
@@ -58,7 +58,8 @@ int grpc_sockaddr_is_v4mapped(const grpc_resolved_address* resolved_addr,
         /* s6_addr32 would be nice, but it's non-standard. */
         memcpy(&addr4_out->sin_addr, &addr6->sin6_addr.s6_addr[12], 4);
         addr4_out->sin_port = addr6->sin6_port;
-        resolved_addr4_out->len = sizeof(grpc_sockaddr_in);
+        resolved_addr4_out->len =
+            static_cast<socklen_t>(sizeof(grpc_sockaddr_in));
       }
       return 1;
     }
@@ -81,7 +82,7 @@ int grpc_sockaddr_to_v4mapped(const grpc_resolved_address* resolved_addr,
     memcpy(&addr6_out->sin6_addr.s6_addr[0], kV4MappedPrefix, 12);
     memcpy(&addr6_out->sin6_addr.s6_addr[12], &addr4->sin_addr, 4);
     addr6_out->sin6_port = addr4->sin_port;
-    resolved_addr6_out->len = sizeof(grpc_sockaddr_in6);
+    resolved_addr6_out->len = static_cast<socklen_t>(sizeof(grpc_sockaddr_in6));
     return 1;
   }
   return 0;
@@ -135,7 +136,7 @@ void grpc_sockaddr_make_wildcard4(int port,
   memset(resolved_wild_out, 0, sizeof(*resolved_wild_out));
   wild_out->sin_family = GRPC_AF_INET;
   wild_out->sin_port = grpc_htons(static_cast<uint16_t>(port));
-  resolved_wild_out->len = sizeof(grpc_sockaddr_in);
+  resolved_wild_out->len = static_cast<socklen_t>(sizeof(grpc_sockaddr_in));
 }
 
 void grpc_sockaddr_make_wildcard6(int port,
@@ -146,7 +147,7 @@ void grpc_sockaddr_make_wildcard6(int port,
   memset(resolved_wild_out, 0, sizeof(*resolved_wild_out));
   wild_out->sin6_family = GRPC_AF_INET6;
   wild_out->sin6_port = grpc_htons(static_cast<uint16_t>(port));
-  resolved_wild_out->len = sizeof(grpc_sockaddr_in6);
+  resolved_wild_out->len = static_cast<socklen_t>(sizeof(grpc_sockaddr_in6));
 }
 
 int grpc_sockaddr_to_string(char** out,
diff --git a/src/core/lib/iomgr/socket_utils_linux.cc b/src/core/lib/iomgr/socket_utils_linux.cc
index 1364cd35f6..f506329f97 100644
--- a/src/core/lib/iomgr/socket_utils_linux.cc
+++ b/src/core/lib/iomgr/socket_utils_linux.cc
@@ -38,7 +38,7 @@ int grpc_accept4(int sockfd, grpc_resolved_address* resolved_addr, int nonblock,
   flags |= nonblock ? SOCK_NONBLOCK : 0;
   flags |= cloexec ? SOCK_CLOEXEC : 0;
   return accept4(sockfd, reinterpret_cast<grpc_sockaddr*>(resolved_addr->addr),
-                 reinterpret_cast<socklen_t*>(&resolved_addr->len), flags);
+                 &resolved_addr->len, flags);
 }
 
 #endif
diff --git a/src/core/lib/iomgr/tcp_client_posix.cc b/src/core/lib/iomgr/tcp_client_posix.cc
index c21fb40ab1..ba943d302a 100644
--- a/src/core/lib/iomgr/tcp_client_posix.cc
+++ b/src/core/lib/iomgr/tcp_client_posix.cc
@@ -295,7 +295,7 @@ void grpc_tcp_client_create_from_prepared_fd(
   do {
     GPR_ASSERT(addr->len < ~(socklen_t)0);
     err = connect(fd, reinterpret_cast<const grpc_sockaddr*>(addr->addr),
-                  static_cast<socklen_t>(addr->len));
+                  addr->len);
   } while (err < 0 && errno == EINTR);
   if (err >= 0) {
     char* addr_str = grpc_sockaddr_to_uri(addr);
diff --git a/src/core/lib/iomgr/tcp_server_posix.cc b/src/core/lib/iomgr/tcp_server_posix.cc
index 631cd07f67..4e1d90e86a 100644
--- a/src/core/lib/iomgr/tcp_server_posix.cc
+++ b/src/core/lib/iomgr/tcp_server_posix.cc
@@ -219,7 +219,7 @@ static void on_read(void* arg, grpc_error* err) {
     char* addr_str;
     char* name;
     memset(&addr, 0, sizeof(addr));
-    addr.len = sizeof(struct sockaddr_storage);
+    addr.len = static_cast<socklen_t>(sizeof(struct sockaddr_storage));
     /* Note: If we ever decide to return this address to the user, remember to
        strip off the ::ffff:0.0.0.0/96 prefix first. */
     int fd = grpc_accept4(sp->fd, &addr, 1, 1);
@@ -418,11 +418,12 @@ static grpc_error* tcp_server_add_port(grpc_tcp_server* s,
      as some previously created listener. */
   if (requested_port == 0) {
     for (sp = s->head; sp; sp = sp->next) {
-      sockname_temp.len = sizeof(struct sockaddr_storage);
+      sockname_temp.len =
+          static_cast<socklen_t>(sizeof(struct sockaddr_storage));
       if (0 ==
           getsockname(sp->fd,
                       reinterpret_cast<grpc_sockaddr*>(&sockname_temp.addr),
-                      reinterpret_cast<socklen_t*>(&sockname_temp.len))) {
+                      &sockname_temp.len)) {
         int used_port = grpc_sockaddr_get_port(&sockname_temp);
         if (used_port > 0) {
           memcpy(&sockname_temp, addr, sizeof(grpc_resolved_address));
diff --git a/src/core/lib/iomgr/tcp_server_utils_posix_common.cc b/src/core/lib/iomgr/tcp_server_utils_posix_common.cc
index 76d3d62940..0734453364 100644
--- a/src/core/lib/iomgr/tcp_server_utils_posix_common.cc
+++ b/src/core/lib/iomgr/tcp_server_utils_posix_common.cc
@@ -172,7 +172,7 @@ grpc_error* grpc_tcp_server_prepare_socket(int fd,
 
   GPR_ASSERT(addr->len < ~(socklen_t)0);
   if (bind(fd, reinterpret_cast<grpc_sockaddr*>(const_cast<char*>(addr->addr)),
-           static_cast<socklen_t>(addr->len)) < 0) {
+           addr->len) < 0) {
     err = GRPC_OS_ERROR(errno, "bind");
     goto error;
   }
@@ -182,10 +182,10 @@ grpc_error* grpc_tcp_server_prepare_socket(int fd,
     goto error;
   }
 
-  sockname_temp.len = sizeof(struct sockaddr_storage);
+  sockname_temp.len = static_cast<socklen_t>(sizeof(struct sockaddr_storage));
 
   if (getsockname(fd, reinterpret_cast<grpc_sockaddr*>(sockname_temp.addr),
-                  reinterpret_cast<socklen_t*>(&sockname_temp.len)) < 0) {
+                  &sockname_temp.len) < 0) {
     err = GRPC_OS_ERROR(errno, "getsockname");
     goto error;
   }
diff --git a/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.cc b/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.cc
index 29ff9ecda1..7fd86c57eb 100644
--- a/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.cc
+++ b/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.cc
@@ -68,14 +68,14 @@ static grpc_error* get_unused_port(int* port) {
   if (dsmode == GRPC_DSMODE_IPV4) {
     grpc_sockaddr_make_wildcard4(0, &wild);
   }
-  if (bind(fd, reinterpret_cast<const grpc_sockaddr*>(wild.addr),
-           static_cast<socklen_t>(wild.len)) != 0) {
+  if (bind(fd, reinterpret_cast<const grpc_sockaddr*>(wild.addr), wild.len) !=
+      0) {
     err = GRPC_OS_ERROR(errno, "bind");
     close(fd);
     return err;
   }
-  if (getsockname(fd, reinterpret_cast<grpc_sockaddr*>(wild.addr),
-                  reinterpret_cast<socklen_t*>(&wild.len)) != 0) {
+  if (getsockname(fd, reinterpret_cast<grpc_sockaddr*>(wild.addr), &wild.len) !=
+      0) {
     err = GRPC_OS_ERROR(errno, "getsockname");
     close(fd);
     return err;
@@ -119,9 +119,9 @@ grpc_error* grpc_tcp_server_add_all_local_addrs(grpc_tcp_server* s,
     if (ifa_it->ifa_addr == nullptr) {
       continue;
     } else if (ifa_it->ifa_addr->sa_family == AF_INET) {
-      addr.len = sizeof(grpc_sockaddr_in);
+      addr.len = static_cast<socklen_t>(sizeof(grpc_sockaddr_in));
     } else if (ifa_it->ifa_addr->sa_family == AF_INET6) {
-      addr.len = sizeof(grpc_sockaddr_in6);
+      addr.len = static_cast<socklen_t>(sizeof(grpc_sockaddr_in6));
     } else {
       continue;
     }
diff --git a/src/core/lib/iomgr/udp_server.cc b/src/core/lib/iomgr/udp_server.cc
index 15a242abe2..04716a254d 100644
--- a/src/core/lib/iomgr/udp_server.cc
+++ b/src/core/lib/iomgr/udp_server.cc
@@ -347,7 +347,7 @@ static int bind_socket(grpc_socket_factory* socket_factory, int sockfd,
              : bind(sockfd,
                     reinterpret_cast<grpc_sockaddr*>(
                         const_cast<char*>(addr->addr)),
-                    static_cast<socklen_t>(addr->len));
+                    addr->len);
 }
 
 /* Prepare a recently-created socket for listening. */
@@ -390,10 +390,10 @@ static int prepare_socket(grpc_socket_factory* socket_factory, int fd,
     goto error;
   }
 
-  sockname_temp.len = sizeof(struct sockaddr_storage);
+  sockname_temp.len = static_cast<socklen_t>(sizeof(struct sockaddr_storage));
 
   if (getsockname(fd, reinterpret_cast<grpc_sockaddr*>(sockname_temp.addr),
-                  reinterpret_cast<socklen_t*>(&sockname_temp.len)) < 0) {
+                  &sockname_temp.len) < 0) {
     goto error;
   }
 
@@ -575,10 +575,11 @@ int grpc_udp_server_add_port(grpc_udp_server* s,
      as some previously created listener. */
   if (grpc_sockaddr_get_port(addr) == 0) {
     for (size_t i = 0; i < s->listeners.size(); ++i) {
-      sockname_temp.len = sizeof(struct sockaddr_storage);
+      sockname_temp.len =
+          static_cast<socklen_t>(sizeof(struct sockaddr_storage));
       if (0 == getsockname(s->listeners[i].fd(),
                            reinterpret_cast<grpc_sockaddr*>(sockname_temp.addr),
-                           reinterpret_cast<socklen_t*>(&sockname_temp.len))) {
+                           &sockname_temp.len)) {
         port = grpc_sockaddr_get_port(&sockname_temp);
         if (port > 0) {
           allocated_addr = static_cast<grpc_resolved_address*>(
diff --git a/src/core/lib/iomgr/unix_sockets_posix.cc b/src/core/lib/iomgr/unix_sockets_posix.cc
index 5d09b4a9b1..22fcaf57fc 100644
--- a/src/core/lib/iomgr/unix_sockets_posix.cc
+++ b/src/core/lib/iomgr/unix_sockets_posix.cc
@@ -61,7 +61,8 @@ grpc_error* grpc_resolve_unix_domain_address(const char* name,
   un = reinterpret_cast<struct sockaddr_un*>((*addrs)->addrs->addr);
   un->sun_family = AF_UNIX;
   strncpy(un->sun_path, name, sizeof(un->sun_path));
-  (*addrs)->addrs->len = strlen(un->sun_path) + sizeof(un->sun_family) + 1;
+  (*addrs)->addrs->len =
+      static_cast<socklen_t>(strlen(un->sun_path) + sizeof(un->sun_family) + 1);
   return GRPC_ERROR_NONE;
 }
 
diff --git a/src/core/lib/json/json.cc b/src/core/lib/json/json.cc
index 816241bbf0..2141db4c5b 100644
--- a/src/core/lib/json/json.cc
+++ b/src/core/lib/json/json.cc
@@ -21,7 +21,6 @@
 #include <string.h>
 
 #include <grpc/support/alloc.h>
-#include <grpc/support/log.h>
 
 #include "src/core/lib/json/json.h"
 
@@ -47,40 +46,5 @@ void grpc_json_destroy(grpc_json* json) {
     json->parent->child = json->next;
   }
 
-  if (json->owns_value) {
-    gpr_free((void*)json->value);
-  }
-
   gpr_free(json);
 }
-
-grpc_json* grpc_json_link_child(grpc_json* parent, grpc_json* child,
-                                grpc_json* sibling) {
-  // first child case.
-  if (parent->child == nullptr) {
-    GPR_ASSERT(sibling == nullptr);
-    parent->child = child;
-    return child;
-  }
-  if (sibling == nullptr) {
-    sibling = parent->child;
-  }
-  // always find the right most sibling.
-  while (sibling->next != nullptr) {
-    sibling = sibling->next;
-  }
-  sibling->next = child;
-  return child;
-}
-
-grpc_json* grpc_json_create_child(grpc_json* sibling, grpc_json* parent,
-                                  const char* key, const char* value,
-                                  grpc_json_type type, bool owns_value) {
-  grpc_json* child = grpc_json_create(type);
-  grpc_json_link_child(parent, child, sibling);
-  child->owns_value = owns_value;
-  child->parent = parent;
-  child->value = value;
-  child->key = key;
-  return child;
-}
diff --git a/src/core/lib/json/json.h b/src/core/lib/json/json.h
index f93b43048b..3a62ef9cfb 100644
--- a/src/core/lib/json/json.h
+++ b/src/core/lib/json/json.h
@@ -21,7 +21,6 @@
 
 #include <grpc/support/port_platform.h>
 
-#include <stdbool.h>
 #include <stdlib.h>
 
 #include "src/core/lib/json/json_common.h"
@@ -38,9 +37,6 @@ typedef struct grpc_json {
   grpc_json_type type;
   const char* key;
   const char* value;
-
-  /* if set, destructor will free value */
-  bool owns_value;
 } grpc_json;
 
 /* The next two functions are going to parse the input string, and
@@ -71,24 +67,9 @@ char* grpc_json_dump_to_string(grpc_json* json, int indent);
 
 /* Use these to create or delete a grpc_json object.
  * Deletion is recursive. We will not attempt to free any of the strings
- * in any of the objects of that tree, unless the boolean, owns_value,
- * is true.
+ * in any of the objects of that tree.
  */
 grpc_json* grpc_json_create(grpc_json_type type);
 void grpc_json_destroy(grpc_json* json);
 
-/* Links the child json object into the parent's json tree. If the parent
- * already has children, then passing in the most recently added child as the
- * sibling parameter is an optimization. For if sibling is NULL, this function
- * will manually traverse the tree in order to find the right most sibling.
- */
-grpc_json* grpc_json_link_child(grpc_json* parent, grpc_json* child,
-                                grpc_json* sibling);
-
-/* Creates a child json object into the parent's json tree then links it in
- * as described above. */
-grpc_json* grpc_json_create_child(grpc_json* sibling, grpc_json* parent,
-                                  const char* key, const char* value,
-                                  grpc_json_type type, bool owns_value);
-
 #endif /* GRPC_CORE_LIB_JSON_JSON_H */
diff --git a/src/core/lib/surface/channel.cc b/src/core/lib/surface/channel.cc
index cecc15b2df..03353d6beb 100644
--- a/src/core/lib/surface/channel.cc
+++ b/src/core/lib/surface/channel.cc
@@ -21,7 +21,6 @@
 #include "src/core/lib/surface/channel.h"
 
 #include <inttypes.h>
-#include <limits.h>
 #include <stdlib.h>
 #include <string.h>
 
@@ -31,12 +30,8 @@
 #include <grpc/support/string_util.h>
 
 #include "src/core/lib/channel/channel_args.h"
-#include "src/core/lib/channel/channel_trace.h"
 #include "src/core/lib/debug/stats.h"
 #include "src/core/lib/gpr/string.h"
-#include "src/core/lib/gprpp/manual_constructor.h"
-#include "src/core/lib/gprpp/memory.h"
-#include "src/core/lib/gprpp/ref_counted_ptr.h"
 #include "src/core/lib/iomgr/iomgr.h"
 #include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/surface/api_trace.h"
@@ -67,8 +62,6 @@ struct grpc_channel {
   gpr_mu registered_call_mu;
   registered_call* registered_calls;
 
-  grpc_core::RefCountedPtr<grpc_core::ChannelTrace> tracer;
-
   char* target;
 };
 
@@ -100,14 +93,12 @@ grpc_channel* grpc_channel_create_with_builder(
             grpc_error_string(error));
     GRPC_ERROR_UNREF(error);
     gpr_free(target);
-    grpc_channel_args_destroy(args);
-    return channel;
+    goto done;
   }
 
   memset(channel, 0, sizeof(*channel));
   channel->target = target;
   channel->is_client = grpc_channel_stack_type_is_client(channel_stack_type);
-  size_t channel_tracer_max_nodes = 0;  // default to off
   gpr_mu_init(&channel->registered_call_mu);
   channel->registered_calls = nullptr;
 
@@ -170,33 +161,14 @@ grpc_channel* grpc_channel_create_with_builder(
       channel->compression_options.enabled_algorithms_bitset =
           static_cast<uint32_t>(args->args[i].value.integer) |
           0x1; /* always support no compression */
-    } else if (0 == strcmp(args->args[i].key,
-                           GRPC_ARG_MAX_CHANNEL_TRACE_EVENTS_PER_NODE)) {
-      GPR_ASSERT(channel_tracer_max_nodes == 0);
-      // max_nodes defaults to 0 (which is off), clamped between 0 and INT_MAX
-      const grpc_integer_options options = {0, 0, INT_MAX};
-      channel_tracer_max_nodes =
-          (size_t)grpc_channel_arg_get_integer(&args->args[i], options);
     }
   }
 
+done:
   grpc_channel_args_destroy(args);
-  channel->tracer = grpc_core::MakeRefCounted<grpc_core::ChannelTrace>(
-      channel_tracer_max_nodes);
-  channel->tracer->AddTraceEvent(
-      grpc_core::ChannelTrace::Severity::Info,
-      grpc_slice_from_static_string("Channel created"));
   return channel;
 }
 
-char* grpc_channel_get_trace(grpc_channel* channel) {
-  return channel->tracer->RenderTrace();
-}
-
-intptr_t grpc_channel_get_uuid(grpc_channel* channel) {
-  return channel->tracer->GetUuid();
-}
-
 grpc_channel* grpc_channel_create(const char* target,
                                   const grpc_channel_args* input_args,
                                   grpc_channel_stack_type channel_stack_type,
@@ -405,7 +377,6 @@ static void destroy_channel(void* arg, grpc_error* error) {
     GRPC_MDELEM_UNREF(rc->authority);
     gpr_free(rc);
   }
-  channel->tracer.reset();
   GRPC_MDELEM_UNREF(channel->default_authority);
   gpr_mu_destroy(&channel->registered_call_mu);
   gpr_free(channel->target);
diff --git a/src/core/lib/surface/init.cc b/src/core/lib/surface/init.cc
index bd436d6857..ac9f9e6066 100644
--- a/src/core/lib/surface/init.cc
+++ b/src/core/lib/surface/init.cc
@@ -27,7 +27,6 @@
 #include <grpc/support/log.h>
 #include <grpc/support/time.h>
 #include "src/core/lib/channel/channel_stack.h"
-#include "src/core/lib/channel/channel_trace_registry.h"
 #include "src/core/lib/channel/connected_channel.h"
 #include "src/core/lib/channel/handshaker_registry.h"
 #include "src/core/lib/debug/stats.h"
@@ -129,7 +128,6 @@ void grpc_init(void) {
     grpc_slice_intern_init();
     grpc_mdctx_global_init();
     grpc_channel_init_init();
-    grpc_channel_trace_registry_init();
     grpc_security_pre_init();
     grpc_core::ExecCtx::GlobalInit();
     grpc_iomgr_init();
@@ -178,7 +176,6 @@ void grpc_shutdown(void) {
       grpc_mdctx_global_shutdown();
       grpc_handshaker_factory_registry_shutdown();
       grpc_slice_intern_shutdown();
-      grpc_channel_trace_registry_shutdown();
       grpc_stats_shutdown();
     }
     grpc_core::ExecCtx::GlobalShutdown();
diff --git a/src/proto/grpc/channelz/BUILD b/src/proto/grpc/channelz/BUILD
deleted file mode 100644
index bdb03d5e2d..0000000000
--- a/src/proto/grpc/channelz/BUILD
+++ /dev/null
@@ -1,26 +0,0 @@
-# Copyright 2018 gRPC authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-licenses(["notice"])  # Apache v2
-
-load("//bazel:grpc_build_system.bzl", "grpc_proto_library", "grpc_package")
-
-grpc_package(name = "channelz", visibility = "public")
-
-grpc_proto_library(
-    name = "channelz_proto",
-    srcs = ["channelz.proto"],
-    has_services = True,
-    well_known_protos = True,
-)
diff --git a/src/proto/grpc/channelz/channelz.proto b/src/proto/grpc/channelz/channelz.proto
deleted file mode 100644
index 14db66a654..0000000000
--- a/src/proto/grpc/channelz/channelz.proto
+++ /dev/null
@@ -1,456 +0,0 @@
-// Copyright 2018 gRPC authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-syntax = "proto3";
-
-package grpc.channelz;
-
-import "google/protobuf/any.proto";
-import "google/protobuf/duration.proto";
-import "google/protobuf/timestamp.proto";
-import "google/protobuf/wrappers.proto";
-
-// See go/grpc-channelz.
-
-// Channel is a logical grouping of channels, subchannels, and sockets.
-message Channel {
-  // The identifier for this channel.
-  ChannelRef ref = 1;
-  // Data specific to this channel.
-  ChannelData data = 2;
-  // At most one of 'channel_ref+subchannel_ref' and 'socket' is set.
-
-  // There are no ordering guarantees on the order of channel refs.
-  // There may not be cycles in the ref graph.
-  // A channel ref may be present in more than one channel or subchannel.
-  repeated ChannelRef channel_ref = 3;
-
-  // At most one of 'channel_ref+subchannel_ref' and 'socket' is set.
-  // There are no ordering guarantees on the order of subchannel refs.
-  // There may not be cycles in the ref graph.
-  // A sub channel ref may be present in more than one channel or subchannel.
-  repeated SubchannelRef subchannel_ref = 4;
-
-  // There are no ordering guarantees on the order of sockets.
-  repeated SocketRef socket = 5;
-}
-
-// Subchannel is a logical grouping of channels, subchannels, and sockets.
-// A subchannel is load balanced over by it's ancestor
-message Subchannel {
-  // The identifier for this channel.
-  SubchannelRef ref = 1;
-  // Data specific to this channel.
-  ChannelData data = 2;
-  // At most one of 'channel_ref+subchannel_ref' and 'socket' is set.
-
-  // There are no ordering guarantees on the order of channel refs.
-  // There may not be cycles in the ref graph.
-  // A channel ref may be present in more than one channel or subchannel.
-  repeated ChannelRef channel_ref = 3;
-
-  // At most one of 'channel_ref+subchannel_ref' and 'socket' is set.
-  // There are no ordering guarantees on the order of subchannel refs.
-  // There may not be cycles in the ref graph.
-  // A sub channel ref may be present in more than one channel or subchannel.
-  repeated SubchannelRef subchannel_ref = 4;
-
-  // There are no ordering guarantees on the order of sockets.
-  repeated SocketRef socket = 5;
-}
-
-// These come from the specified states in this document:
-// https://github.com/grpc/grpc/blob/master/doc/connectivity-semantics-and-api.md
-message ChannelConnectivityState {
-  enum State {
-    UNKNOWN = 0;
-    IDLE = 1;
-    CONNECTING = 2;
-    READY = 3;
-    TRANSIENT_FAILURE = 4;
-    SHUTDOWN = 5;
-  }
-  State state = 1;
-}
-
-message ChannelData {
-
-  ChannelConnectivityState state = 1;
-
-  // The target this channel originally tried to connect to.  May be absent
-  string target = 2;
-
-  ChannelTrace trace = 3;
-
-  // The number of calls started on the channel
-  int64 calls_started = 4;
-  // The number of calls that have completed with an OK status
-  int64 calls_succeeded = 5;
-  // The number of calls that have a completed with a non-OK status
-  int64 calls_failed = 6;
-
-  // The last time a call was started on the channel.
-  google.protobuf.Timestamp last_call_started_timestamp = 7;
-}
-
-// A trace event is an interesting thing that happened to a channel or
-// subchannel, such as creation, address resolution, subchannel creation, etc.
-message ChannelTraceEvent {
-  // High level description of the event.
-  string description = 1;
-  // The supported severity levels of trace events.
-  enum Severity {
-    CT_UNKNOWN = 0;
-    CT_INFO = 1;
-    CT_WARNING = 2;
-    CT_ERROR = 3;
-  }
-  // the severity of the trace event
-  Severity severity = 2;
-  // When this event occurred.
-  google.protobuf.Timestamp timestamp = 3;
-  // ref of referenced channel or subchannel.
-  // Optional, only present if this event refers to a child object. For example,
-  // this field would be filled if this trace event was for a subchannel being
-  // created.
-  oneof child_ref {
-    ChannelRef channel_ref = 4;
-    SubchannelRef subchannel_ref = 5;
-  }
-}
-
-message ChannelTrace {
-  // Number of events ever logged in this tracing object. This can differ from
-  // events.size() because events can be overwritten or garbage collected by
-  // implementations.
-  int64 num_events_logged = 1;
-  // Time that this channel was created.
-  google.protobuf.Timestamp creation_time = 2;
-  // List of events that have occurred on this channel.
-  repeated ChannelTraceEvent events = 3;
-}
-
-message ChannelRef {
-  // The globally unique id for this channel.  Must be a positive number.
-  int64 channel_id = 1;
-  // An optional name associated with the channel.
-  string name = 2;
-  // Intentionally don't use field numbers from other refs.
-  reserved 3, 4, 5, 6;
-}
-
-message SubchannelRef {
-  // The globally unique id for this subchannel.  Must be a positive number.
-  int64 subchannel_id = 7;
-  // An optional name associated with the subchannel.
-  string name = 8;
-  // Intentionally don't use field numbers from other refs.
-  reserved 1, 2, 3, 4, 5, 6;
-}
-
-message SocketRef {
-  int64 socket_id = 3;
-  // An optional name associated with the socket.
-  string name = 4;
-  // Intentionally don't use field numbers from other refs.
-  reserved 1, 2, 5, 6, 7, 8;
-}
-
-message ServerRef {
-  // A globally unique identifier for this server.   Must be a positive number.
-  int64 server_id = 5;
-  // An optional name associated with the server.
-  string name = 6;
-  // Intentionally don't use field numbers from other refs.
-  reserved 1, 2, 3, 4, 7, 8;
-}
-
-message Server {
-  ServerRef ref = 1;
-  ServerData data = 2;
-
-  // The sockets that the server is listening on.  There are no ordering
-  // guarantees.
-  repeated SocketRef listen_socket = 3;
-}
-
-message ServerData {
-  ChannelTrace trace = 1;
-
-  // The number of incoming calls started on the server
-  int64 calls_started = 2;
-  // The number of incoming calls that have completed with an OK status
-  int64 calls_succeeded = 3;
-  // The number of incoming calls that have a completed with a non-OK status
-  int64 calls_failed = 4;
-
-  // The last time a call was started on the server.
-  google.protobuf.Timestamp last_call_started_timestamp = 5;
-}
-
-// Information about an actual connection.  Pronounced "sock-ay".
-message Socket {
-  SocketRef ref = 1;
-
-  SocketData data = 2;
-  // The locally bound address.
-  Address local = 3;
-  // The remote bound address.  May be absent.
-  Address remote = 4;
-  Security security = 5;
-
-  // Optional, represents the name of the remote endpoint, if different than
-  // the original target name.
-  string remote_name = 6;
-}
-
-message SocketData {
-  // The number of streams that have been started.
-  int64 streams_started = 1;
-  // The number of streams that have ended successfully with the EoS bit set for
-  //  both end points
-  int64 streams_succeeded = 2;
-  // The number of incoming streams that have a completed with a non-OK status
-  int64 streams_failed = 3;
-
-  // The number of messages successfully sent on this socket.
-  int64 messages_sent = 4;
-  int64 messages_received = 5;
-
-  // The number of keep alives sent.  This is typically implemented with HTTP/2
-  // ping messages.
-  int64 keep_alives_sent = 6;
-
-  // The last time a stream was created by this endpoint.  Usually unset for
-  // servers.
-  google.protobuf.Timestamp last_local_stream_created_timestamp = 7;
-  // The last time a stream was created by the remote endpoint.  Usually unset
-  // for clients.
-  google.protobuf.Timestamp last_remote_stream_created_timestamp = 8;
-
-  // The last time a message was sent by this endpoint.
-  google.protobuf.Timestamp last_message_sent_timestamp = 9;
-  // The last time a message was received by this endpoint.
-  google.protobuf.Timestamp last_message_received_timestamp = 10;
-
-  // The amount of window, granted to the local endpoint by the remote endpoint.
-  // This may be slightly out of date due to network latency.  This does NOT
-  // include stream level or TCP level flow control info.
-  google.protobuf.Int64Value local_flow_control_window = 11;
-
-  // The amount of window, granted to the remote endpoint by the local endpoint.
-  // This may be slightly out of date due to network latency.  This does NOT
-  // include stream level or TCP level flow control info.
-  google.protobuf.Int64Value  remote_flow_control_window = 12;
-
-  repeated SocketOption option = 13;
-}
-
-message Address {
-  message TcpIpAddress {
-    // Either the IPv4 or IPv6 address in bytes.  Will either be 4 bytes or 16
-    // bytes in length.
-    bytes ip_address = 1;
-    // 0-64k, or -1 if not appropriate.
-    int32 port = 2;
-  }
-  // A Unix Domain Socket address.
-  message UdsAddress {
-    string filename = 1;
-  }
-  // An address type not included above.
-  message OtherAddress {
-    // The human readable version of the value.
-    string name = 1;
-    // The actual address message.
-    google.protobuf.Any value = 2;
-  }
-
-  oneof address {
-    TcpIpAddress tcpip_address = 1;
-    UdsAddress uds_address = 2;
-    OtherAddress other_address = 3;
-  }
-}
-
-message Security {
-  message Tls {
-    // The key exchange used.  e.g. X25519
-    string key_exchange = 1;
-    // The cipher used. e.g. AES_128_GCM.
-    string cipher = 2;
-    // the certificate used by this endpoint.
-    bytes local_certificate = 3;
-    // the certificate used by the remote endpoint.
-    bytes remote_certificate = 4;
-  }
-  message OtherSecurity {
-    // The human readable version of the value.
-    string name = 1;
-    // The actual security details message.
-    google.protobuf.Any value = 2;
-  }
-  oneof model {
-    Tls tls = 1;
-    OtherSecurity other = 2;
-  }
-}
-
-message SocketOption {
-  string name = 1;
-  // The human readable value of this socket option.  At least one of value or
-  // additional will be set.
-  string value = 2;
-  // Additional data associated with the socket option.  At least one of value
-  // or additional will be set.
-  google.protobuf.Any additional = 3;
-}
-
-// For use with SocketOption's additional field.  This is primarily used for
-// SO_RCVTIMEO and SO_SNDTIMEO
-message SocketOptionTimeout {
-  google.protobuf.Duration duration = 1;
-}
-
-message SocketOptionLinger {
-  bool active = 1;
-  google.protobuf.Duration duration = 2;
-}
-
-// Tcp info for SOL_TCP, TCP_INFO
-message SocketOptionTcpInfo {
-  uint32 tcpi_state = 1;
-
-  uint32 tcpi_ca_state = 2;
-  uint32 tcpi_retransmits = 3;
-  uint32 tcpi_probes = 4;
-  uint32 tcpi_backoff = 5;
-  uint32 tcpi_options = 6;
-  uint32 tcpi_snd_wscale = 7;
-  uint32 tcpi_rcv_wscale = 8;
-
-  uint32 tcpi_rto = 9;
-  uint32 tcpi_ato = 10;
-  uint32 tcpi_snd_mss = 11;
-  uint32 tcpi_rcv_mss = 12;
-
-  uint32 tcpi_unacked = 13;
-  uint32 tcpi_sacked = 14;
-  uint32 tcpi_lost = 15;
-  uint32 tcpi_retrans = 16;
-  uint32 tcpi_fackets = 17;
-
-  uint32 tcpi_last_data_sent = 18;
-  uint32 tcpi_last_ack_sent = 19;
-  uint32 tcpi_last_data_recv = 20;
-  uint32 tcpi_last_ack_recv = 21;
-
-  uint32 tcpi_pmtu = 22;
-  uint32 tcpi_rcv_ssthresh = 23;
-  uint32 tcpi_rtt = 24;
-  uint32 tcpi_rttvar = 25;
-  uint32 tcpi_snd_ssthresh = 26;
-  uint32 tcpi_snd_cwnd = 27;
-  uint32 tcpi_advmss = 28;
-  uint32 tcpi_reordering = 29;
-}
-
-service Channelz {
-  // Gets all root channels (e.g. channels the application has directly
-  // created). This does not include subchannels nor non-top level channels.
-  rpc GetTopChannels(GetTopChannelsRequest) returns (GetTopChannelsResponse);
-  // Gets all servers that exist in the process.
-  rpc GetServers(GetServersRequest) returns (GetServersResponse);
-  // Gets all server sockets that exist in the process.
-  rpc GetServerSockets(GetServerSocketsRequest) returns (GetServerSocketsResponse);
-  // Returns a single Channel, or else a NOT_FOUND code.
-  rpc GetChannel(GetChannelRequest) returns (GetChannelResponse);
-  // Returns a single Subchannel, or else a NOT_FOUND code.
-  rpc GetSubchannel(GetSubchannelRequest) returns (GetSubchannelResponse);
-  // Returns a single Socket or else a NOT_FOUND code.
-  rpc GetSocket(GetSocketRequest) returns (GetSocketResponse);
-}
-
-message GetServersRequest {
-  // start_server_id indicates that only servers at or above this id should be
-  // included in the results.
-  int64 start_server_id = 1;
-}
-
-message GetServersResponse {
-  // list of servers that the connection detail service knows about.  Sorted in
-  // ascending server_id order.
-  repeated Server server = 1;
-  // If set, indicates that the list of servers is the final list.  Requesting
-  // more servers will only return more if they are created after this RPC
-  // completes.
-  bool end = 2;
-}
-
-message GetServerSocketsRequest {
-  int64 server_id = 1;
-  // start_socket_id indicates that only sockets at or above this id should be
-  // included in the results.
-  int64 start_socket_id = 2;
-}
-
-message GetServerSocketsResponse {
-  // list of socket refs that the connection detail service knows about.  Sorted in
-  // ascending socket_id order.
-  repeated SocketRef socket_ref = 1;
-  // If set, indicates that the list of sockets is the final list.  Requesting
-  // more sockets will only return more if they are created after this RPC
-  // completes.
-  bool end = 2;
-}
-
-message GetTopChannelsRequest {
-  // start_channel_id indicates that only channels at or above this id should be
-  // included in the results.
-  int64 start_channel_id = 1;
-}
-
-message GetTopChannelsResponse {
-  // list of channels that the connection detail service knows about.  Sorted in
-  // ascending channel_id order.
-  repeated Channel channel = 1;
-  // If set, indicates that the list of channels is the final list.  Requesting
-  // more channels can only return more if they are created after this RPC
-  // completes.
-  bool end = 2;
-}
-
-message GetChannelRequest {
-  int64 channel_id = 1;
-}
-
-message GetChannelResponse {
-  Channel channel = 1;
-}
-
-message GetSubchannelRequest {
-  int64 subchannel_id = 1;
-}
-
-message GetSubchannelResponse {
-  Subchannel subchannel = 1;
-}
-
-message GetSocketRequest {
-  int64 socket_id = 1;
-}
-
-message GetSocketResponse {
-  Socket socket = 1;
-}
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index 9807300527..d96cbec292 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -60,13 +60,10 @@ CORE_SOURCE_FILES = [
     'src/core/lib/channel/channel_args.cc',
     'src/core/lib/channel/channel_stack.cc',
     'src/core/lib/channel/channel_stack_builder.cc',
-    'src/core/lib/channel/channel_trace.cc',
-    'src/core/lib/channel/channel_trace_registry.cc',
     'src/core/lib/channel/connected_channel.cc',
     'src/core/lib/channel/handshaker.cc',
     'src/core/lib/channel/handshaker_factory.cc',
     'src/core/lib/channel/handshaker_registry.cc',
-    'src/core/lib/channel/status_util.cc',
     'src/core/lib/compression/compression.cc',
     'src/core/lib/compression/compression_internal.cc',
     'src/core/lib/compression/message_compress.cc',
@@ -315,6 +312,7 @@ CORE_SOURCE_FILES = [
     'src/core/ext/filters/client_channel/resolver.cc',
     'src/core/ext/filters/client_channel/resolver_registry.cc',
     'src/core/ext/filters/client_channel/retry_throttle.cc',
+    'src/core/ext/filters/client_channel/status_util.cc',
     'src/core/ext/filters/client_channel/subchannel.cc',
     'src/core/ext/filters/client_channel/subchannel_index.cc',
     'src/core/ext/filters/client_channel/uri_parser.cc',
diff --git a/src/ruby/ext/grpc/rb_grpc_imports.generated.c b/src/ruby/ext/grpc/rb_grpc_imports.generated.c
index 1c042739a8..c045480ff4 100644
--- a/src/ruby/ext/grpc/rb_grpc_imports.generated.c
+++ b/src/ruby/ext/grpc/rb_grpc_imports.generated.c
@@ -68,8 +68,6 @@ grpc_channel_get_info_type grpc_channel_get_info_import;
 grpc_insecure_channel_create_type grpc_insecure_channel_create_import;
 grpc_lame_client_channel_create_type grpc_lame_client_channel_create_import;
 grpc_channel_destroy_type grpc_channel_destroy_import;
-grpc_channel_get_trace_type grpc_channel_get_trace_import;
-grpc_channel_get_uuid_type grpc_channel_get_uuid_import;
 grpc_call_cancel_type grpc_call_cancel_import;
 grpc_call_cancel_with_status_type grpc_call_cancel_with_status_import;
 grpc_call_ref_type grpc_call_ref_import;
@@ -306,8 +304,6 @@ void grpc_rb_load_imports(HMODULE library) {
   grpc_insecure_channel_create_import = (grpc_insecure_channel_create_type) GetProcAddress(library, "grpc_insecure_channel_create");
   grpc_lame_client_channel_create_import = (grpc_lame_client_channel_create_type) GetProcAddress(library, "grpc_lame_client_channel_create");
   grpc_channel_destroy_import = (grpc_channel_destroy_type) GetProcAddress(library, "grpc_channel_destroy");
-  grpc_channel_get_trace_import = (grpc_channel_get_trace_type) GetProcAddress(library, "grpc_channel_get_trace");
-  grpc_channel_get_uuid_import = (grpc_channel_get_uuid_type) GetProcAddress(library, "grpc_channel_get_uuid");
   grpc_call_cancel_import = (grpc_call_cancel_type) GetProcAddress(library, "grpc_call_cancel");
   grpc_call_cancel_with_status_import = (grpc_call_cancel_with_status_type) GetProcAddress(library, "grpc_call_cancel_with_status");
   grpc_call_ref_import = (grpc_call_ref_type) GetProcAddress(library, "grpc_call_ref");
diff --git a/src/ruby/ext/grpc/rb_grpc_imports.generated.h b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
index 9a09321364..4f07452c68 100644
--- a/src/ruby/ext/grpc/rb_grpc_imports.generated.h
+++ b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
@@ -179,12 +179,6 @@ extern grpc_lame_client_channel_create_type grpc_lame_client_channel_create_impo
 typedef void(*grpc_channel_destroy_type)(grpc_channel* channel);
 extern grpc_channel_destroy_type grpc_channel_destroy_import;
 #define grpc_channel_destroy grpc_channel_destroy_import
-typedef char*(*grpc_channel_get_trace_type)(grpc_channel* channel);
-extern grpc_channel_get_trace_type grpc_channel_get_trace_import;
-#define grpc_channel_get_trace grpc_channel_get_trace_import
-typedef intptr_t(*grpc_channel_get_uuid_type)(grpc_channel* channel);
-extern grpc_channel_get_uuid_type grpc_channel_get_uuid_import;
-#define grpc_channel_get_uuid grpc_channel_get_uuid_import
 typedef grpc_call_error(*grpc_call_cancel_type)(grpc_call* call, void* reserved);
 extern grpc_call_cancel_type grpc_call_cancel_import;
 #define grpc_call_cancel grpc_call_cancel_import