Merge branch 'tracer' of https://github.com/ctiller/grpc into tracing++

include/grpc/grpc.h

@@ -411,7 +411,7 @@ GRPCAPI void grpc_server_destroy(grpc_server *server);
 
 /** Enable or disable a tracer.
 
-    Tracers (usually controlled by the environment variable GRPC_TRACE)
+    TraceFlags (usually controlled by the environment variable GRPC_TRACE)
     allow printf-style debugging on GRPC internals, and are useful for
     tracking down problems in the field.
 

src/core/ext/filters/client_channel/channel_connectivity.cc

@@ -122,7 +122,7 @@ static void partly_done(grpc_exec_ctx *exec_ctx, state_watcher *w,
   gpr_mu_lock(&w->mu);
 
   if (due_to_completion) {
-    if (GRPC_TRACER_ON(grpc_trace_operation_failures)) {
+    if (grpc_trace_operation_failures.enabled()) {
       GRPC_LOG_IF_ERROR("watch_completion_error", GRPC_ERROR_REF(error));
     }
     GRPC_ERROR_UNREF(error);

src/core/ext/filters/client_channel/client_channel.cc

@@ -55,8 +55,7 @@
 
 /* Client channel implementation */
 
-grpc_tracer_flag grpc_client_channel_trace =
-    GRPC_TRACER_INITIALIZER(false, "client_channel");
+grpc_core::TraceFlag grpc_client_channel_trace(false, "client_channel");
 
 /*************************************************************************
  * METHOD-CONFIG TABLE
@@ -250,7 +249,7 @@ static void set_channel_connectivity_state_locked(grpc_exec_ctx *exec_ctx,
                                          GRPC_ERROR_REF(error));
     }
   }
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG, "chand=%p: setting connectivity state to %s", chand,
             grpc_connectivity_state_name(state));
   }
@@ -264,7 +263,7 @@ static void on_lb_policy_state_changed_locked(grpc_exec_ctx *exec_ctx,
   grpc_connectivity_state publish_state = w->state;
   /* check if the notification is for the latest policy */
   if (w->lb_policy == w->chand->lb_policy) {
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "chand=%p: lb_policy=%p state changed to %s", w->chand,
               w->lb_policy, grpc_connectivity_state_name(w->state));
     }
@@ -301,7 +300,7 @@ static void watch_lb_policy_locked(grpc_exec_ctx *exec_ctx, channel_data *chand,
 
 static void start_resolving_locked(grpc_exec_ctx *exec_ctx,
                                    channel_data *chand) {
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG, "chand=%p: starting name resolution", chand);
   }
   GPR_ASSERT(!chand->started_resolving);
@@ -374,7 +373,7 @@ static void parse_retry_throttle_params(const grpc_json *field, void *arg) {
 static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
                                               void *arg, grpc_error *error) {
   channel_data *chand = (channel_data *)arg;
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG, "chand=%p: got resolver result: error=%s", chand,
             grpc_error_string(error));
   }
@@ -483,7 +482,7 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
     grpc_channel_args_destroy(exec_ctx, chand->resolver_result);
     chand->resolver_result = NULL;
   }
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "chand=%p: resolver result: lb_policy_name=\"%s\"%s, "
             "service_config=\"%s\"",
@@ -524,7 +523,7 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
   if (new_lb_policy != NULL || error != GRPC_ERROR_NONE ||
       chand->resolver == NULL) {
     if (chand->lb_policy != NULL) {
-      if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      if (grpc_client_channel_trace.enabled()) {
         gpr_log(GPR_DEBUG, "chand=%p: unreffing lb_policy=%p", chand,
                 chand->lb_policy);
       }
@@ -538,11 +537,11 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
   // Now that we've swapped out the relevant fields of chand, check for
   // error or shutdown.
   if (error != GRPC_ERROR_NONE || chand->resolver == NULL) {
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "chand=%p: shutting down", chand);
     }
     if (chand->resolver != NULL) {
-      if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      if (grpc_client_channel_trace.enabled()) {
         gpr_log(GPR_DEBUG, "chand=%p: shutting down resolver", chand);
       }
       grpc_resolver_shutdown_locked(exec_ctx, chand->resolver);
@@ -565,7 +564,7 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
     grpc_error *state_error =
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("No load balancing policy");
     if (new_lb_policy != NULL) {
-      if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      if (grpc_client_channel_trace.enabled()) {
         gpr_log(GPR_DEBUG, "chand=%p: initializing new LB policy", chand);
       }
       GRPC_ERROR_UNREF(state_error);
@@ -896,7 +895,7 @@ static void waiting_for_pick_batches_fail(grpc_exec_ctx *exec_ctx,
                                           grpc_call_element *elem,
                                           grpc_error *error) {
   call_data *calld = (call_data *)elem->call_data;
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "chand=%p calld=%p: failing %" PRIdPTR " pending batches: %s",
             elem->channel_data, calld, calld->waiting_for_pick_batches_count,
@@ -939,7 +938,7 @@ static void waiting_for_pick_batches_resume(grpc_exec_ctx *exec_ctx,
                                             grpc_call_element *elem) {
   channel_data *chand = (channel_data *)elem->channel_data;
   call_data *calld = (call_data *)elem->call_data;
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG, "chand=%p calld=%p: sending %" PRIdPTR
                        " pending batches to subchannel_call=%p",
             chand, calld, calld->waiting_for_pick_batches_count,
@@ -965,7 +964,7 @@ static void apply_service_config_to_call_locked(grpc_exec_ctx *exec_ctx,
                                                 grpc_call_element *elem) {
   channel_data *chand = (channel_data *)elem->channel_data;
   call_data *calld = (call_data *)elem->call_data;
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG, "chand=%p calld=%p: applying service config to call",
             chand, calld);
   }
@@ -1011,7 +1010,7 @@ static void create_subchannel_call_locked(grpc_exec_ctx *exec_ctx,
   grpc_error *new_error = grpc_connected_subchannel_create_call(
       exec_ctx, calld->connected_subchannel, &call_args,
       &calld->subchannel_call);
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG, "chand=%p calld=%p: create subchannel_call=%p: error=%s",
             chand, calld, calld->subchannel_call, grpc_error_string(new_error));
   }
@@ -1037,7 +1036,7 @@ static void pick_done_locked(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
                              "Call dropped by load balancing policy")
                        : GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                              "Failed to create subchannel", &error, 1);
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG,
               "chand=%p calld=%p: failed to create subchannel: error=%s", chand,
               calld, grpc_error_string(calld->error));
@@ -1071,7 +1070,7 @@ static void pick_callback_cancel_locked(grpc_exec_ctx *exec_ctx, void *arg,
   channel_data *chand = (channel_data *)elem->channel_data;
   call_data *calld = (call_data *)elem->call_data;
   if (calld->lb_policy != NULL) {
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "chand=%p calld=%p: cancelling pick from LB policy %p",
               chand, calld, calld->lb_policy);
     }
@@ -1089,7 +1088,7 @@ static void pick_callback_done_locked(grpc_exec_ctx *exec_ctx, void *arg,
   grpc_call_element *elem = (grpc_call_element *)arg;
   channel_data *chand = (channel_data *)elem->channel_data;
   call_data *calld = (call_data *)elem->call_data;
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG, "chand=%p calld=%p: pick completed asynchronously",
             chand, calld);
   }
@@ -1106,7 +1105,7 @@ static bool pick_callback_start_locked(grpc_exec_ctx *exec_ctx,
                                        grpc_call_element *elem) {
   channel_data *chand = (channel_data *)elem->channel_data;
   call_data *calld = (call_data *)elem->call_data;
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG, "chand=%p calld=%p: starting pick on lb_policy=%p",
             chand, calld, chand->lb_policy);
   }
@@ -1144,7 +1143,7 @@ static bool pick_callback_start_locked(grpc_exec_ctx *exec_ctx,
       calld->subchannel_call_context, NULL, &calld->lb_pick_closure);
   if (pick_done) {
     /* synchronous grpc_lb_policy_pick call. Unref the LB policy. */
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "chand=%p calld=%p: pick completed synchronously",
               chand, calld);
     }
@@ -1190,7 +1189,7 @@ static void pick_after_resolver_result_cancel_locked(grpc_exec_ctx *exec_ctx,
   grpc_call_element *elem = args->elem;
   channel_data *chand = (channel_data *)elem->channel_data;
   call_data *calld = (call_data *)elem->call_data;
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "chand=%p calld=%p: cancelling pick waiting for resolver result",
             chand, calld);
@@ -1212,7 +1211,7 @@ static void pick_after_resolver_result_done_locked(grpc_exec_ctx *exec_ctx,
       (pick_after_resolver_result_args *)arg;
   if (args->finished) {
     /* cancelled, do nothing */
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "call cancelled before resolver result");
     }
     gpr_free(args);
@@ -1223,13 +1222,13 @@ static void pick_after_resolver_result_done_locked(grpc_exec_ctx *exec_ctx,
   channel_data *chand = (channel_data *)elem->channel_data;
   call_data *calld = (call_data *)elem->call_data;
   if (error != GRPC_ERROR_NONE) {
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "chand=%p calld=%p: resolver failed to return data",
               chand, calld);
     }
     async_pick_done_locked(exec_ctx, elem, GRPC_ERROR_REF(error));
   } else {
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "chand=%p calld=%p: resolver returned, doing pick",
               chand, calld);
     }
@@ -1248,7 +1247,7 @@ static void pick_after_resolver_result_start_locked(grpc_exec_ctx *exec_ctx,
                                                     grpc_call_element *elem) {
   channel_data *chand = (channel_data *)elem->channel_data;
   call_data *calld = (call_data *)elem->call_data;
-  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+  if (grpc_client_channel_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "chand=%p calld=%p: deferring pick pending resolver result", chand,
             calld);
@@ -1333,7 +1332,7 @@ static void cc_start_transport_stream_op_batch(
   GPR_TIMER_BEGIN("cc_start_transport_stream_op_batch", 0);
   // If we've previously been cancelled, immediately fail any new batches.
   if (calld->error != GRPC_ERROR_NONE) {
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "chand=%p calld=%p: failing batch with error: %s",
               chand, calld, grpc_error_string(calld->error));
     }
@@ -1349,7 +1348,7 @@ static void cc_start_transport_stream_op_batch(
     // error to the caller when the first batch does get passed down.
     GRPC_ERROR_UNREF(calld->error);
     calld->error = GRPC_ERROR_REF(batch->payload->cancel_stream.cancel_error);
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "chand=%p calld=%p: recording cancel_error=%s", chand,
               calld, grpc_error_string(calld->error));
     }
@@ -1378,7 +1377,7 @@ static void cc_start_transport_stream_op_batch(
   // the channel combiner, which is more efficient (especially for
   // streaming calls).
   if (calld->subchannel_call != NULL) {
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG,
               "chand=%p calld=%p: sending batch to subchannel_call=%p", chand,
               calld, calld->subchannel_call);
@@ -1392,7 +1391,7 @@ static void cc_start_transport_stream_op_batch(
   // For batches containing a send_initial_metadata op, enter the channel
   // combiner to start a pick.
   if (batch->send_initial_metadata) {
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG, "chand=%p calld=%p: entering client_channel combiner",
               chand, calld);
     }
@@ -1403,7 +1402,7 @@ static void cc_start_transport_stream_op_batch(
         GRPC_ERROR_NONE);
   } else {
     // For all other batches, release the call combiner.
-    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    if (grpc_client_channel_trace.enabled()) {
       gpr_log(GPR_DEBUG,
               "chand=%p calld=%p: saved batch, yeilding call combiner", chand,
               calld);

src/core/ext/filters/client_channel/client_channel.h

@@ -23,7 +23,7 @@
 #include "src/core/ext/filters/client_channel/resolver.h"
 #include "src/core/lib/channel/channel_stack.h"
 
-extern grpc_tracer_flag grpc_client_channel_trace;
+extern grpc_core::TraceFlag grpc_client_channel_trace;
 
 // Channel arg key for server URI string.
 #define GRPC_ARG_SERVER_URI "grpc.server_uri"

src/core/ext/filters/client_channel/client_channel_plugin.cc

@@ -78,9 +78,9 @@ extern "C" void grpc_client_channel_init(void) {
       GRPC_CLIENT_CHANNEL, GRPC_CHANNEL_INIT_BUILTIN_PRIORITY, append_filter,
       (void *)&grpc_client_channel_filter);
   grpc_http_connect_register_handshaker_factory();
-  grpc_register_tracer(&grpc_client_channel_trace);
+
 #ifndef NDEBUG
-  grpc_register_tracer(&grpc_trace_resolver_refcount);
+
 #endif
 }
 

src/core/ext/filters/client_channel/lb_policy.cc

@@ -21,10 +21,8 @@
 
 #define WEAK_REF_BITS 16
 
-#ifndef NDEBUG
-grpc_tracer_flag grpc_trace_lb_policy_refcount =
-    GRPC_TRACER_INITIALIZER(false, "lb_policy_refcount");
-#endif
+grpc_core::DebugOnlyTraceFlag grpc_trace_lb_policy_refcount(
+    false, "lb_policy_refcount");
 
 void grpc_lb_policy_init(grpc_lb_policy *policy,
                          const grpc_lb_policy_vtable *vtable,
@@ -52,7 +50,7 @@ static gpr_atm ref_mutate(grpc_lb_policy *c, gpr_atm delta,
   gpr_atm old_val = barrier ? gpr_atm_full_fetch_add(&c->ref_pair, delta)
                             : gpr_atm_no_barrier_fetch_add(&c->ref_pair, delta);
 #ifndef NDEBUG
-  if (GRPC_TRACER_ON(grpc_trace_lb_policy_refcount)) {
+  if (grpc_trace_lb_policy_refcount.enabled()) {
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "LB_POLICY: %p %12s 0x%" PRIxPTR " -> 0x%" PRIxPTR " [%s]", c,
             purpose, old_val, old_val + delta, reason);

src/core/ext/filters/client_channel/lb_policy.h

@@ -34,7 +34,7 @@ typedef struct grpc_lb_policy_vtable grpc_lb_policy_vtable;
 typedef struct grpc_lb_policy_args grpc_lb_policy_args;
 
 #ifndef NDEBUG
-extern grpc_tracer_flag grpc_trace_lb_policy_refcount;
+extern grpc_core::TraceFlag grpc_trace_lb_policy_refcount;
 #endif
 
 struct grpc_lb_policy {

src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc

@@ -126,7 +126,7 @@
 #define GRPC_GRPCLB_RECONNECT_JITTER 0.2
 #define GRPC_GRPCLB_DEFAULT_FALLBACK_TIMEOUT_MS 10000
 
-grpc_tracer_flag grpc_lb_glb_trace = GRPC_TRACER_INITIALIZER(false, "glb");
+grpc_core::TraceFlag grpc_lb_glb_trace(false, "glb");
 
 /* add lb_token of selected subchannel (address) to the call's initial
  * metadata */
@@ -212,7 +212,7 @@ static void wrapped_rr_closure(grpc_exec_ctx *exec_ctx, void *arg,
     } else {
       grpc_grpclb_client_stats_unref(wc_arg->client_stats);
     }
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_INFO, "Unreffing RR %p", (void *)wc_arg->rr_policy);
     }
     GRPC_LB_POLICY_UNREF(exec_ctx, wc_arg->rr_policy, "wrapped_rr_closure");
@@ -618,7 +618,7 @@ static void update_lb_connectivity_status_locked(
       GPR_ASSERT(rr_state_error == GRPC_ERROR_NONE);
   }
 
-  if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+  if (grpc_lb_glb_trace.enabled()) {
     gpr_log(
         GPR_INFO, "Setting grpclb's state to %s from new RR policy %p state.",
         grpc_connectivity_state_name(rr_state), (void *)glb_policy->rr_policy);
@@ -647,7 +647,7 @@ static bool pick_from_internal_rr_locked(
     }
     if (server->drop) {
       // Not using the RR policy, so unref it.
-      if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+      if (grpc_lb_glb_trace.enabled()) {
         gpr_log(GPR_INFO, "Unreffing RR for drop (0x%" PRIxPTR ")",
                 (intptr_t)wc_arg->rr_policy);
       }
@@ -676,7 +676,7 @@ static bool pick_from_internal_rr_locked(
       (void **)&wc_arg->lb_token, &wc_arg->wrapper_closure);
   if (pick_done) {
     /* synchronous grpc_lb_policy_pick call. Unref the RR policy. */
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_INFO, "Unreffing RR (0x%" PRIxPTR ")",
               (intptr_t)wc_arg->rr_policy);
     }
@@ -797,7 +797,7 @@ static void create_rr_locked(grpc_exec_ctx *exec_ctx, glb_lb_policy *glb_policy,
     pp->wrapped_on_complete_arg.rr_policy = glb_policy->rr_policy;
     pp->wrapped_on_complete_arg.client_stats =
         grpc_grpclb_client_stats_ref(glb_policy->client_stats);
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_INFO, "Pending pick about to (async) PICK from %p",
               (void *)glb_policy->rr_policy);
     }
@@ -811,7 +811,7 @@ static void create_rr_locked(grpc_exec_ctx *exec_ctx, glb_lb_policy *glb_policy,
     glb_policy->pending_pings = pping->next;
     GRPC_LB_POLICY_REF(glb_policy->rr_policy, "rr_handover_pending_ping");
     pping->wrapped_notify_arg.rr_policy = glb_policy->rr_policy;
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_INFO, "Pending ping about to PING from 0x%" PRIxPTR "",
               (intptr_t)glb_policy->rr_policy);
     }
@@ -827,14 +827,14 @@ static void rr_handover_locked(grpc_exec_ctx *exec_ctx,
   grpc_lb_policy_args *args = lb_policy_args_create(exec_ctx, glb_policy);
   GPR_ASSERT(args != NULL);
   if (glb_policy->rr_policy != NULL) {
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_DEBUG, "Updating Round Robin policy (%p)",
               (void *)glb_policy->rr_policy);
     }
     grpc_lb_policy_update_locked(exec_ctx, glb_policy->rr_policy, args);
   } else {
     create_rr_locked(exec_ctx, glb_policy, args);
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_DEBUG, "Created new Round Robin policy (%p)",
               (void *)glb_policy->rr_policy);
     }
@@ -1165,7 +1165,7 @@ static int glb_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
   bool pick_done;
 
   if (glb_policy->rr_policy != NULL) {
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_INFO, "grpclb %p about to PICK from RR %p",
               (void *)glb_policy, (void *)glb_policy->rr_policy);
     }
@@ -1190,7 +1190,7 @@ static int glb_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
         pick_from_internal_rr_locked(exec_ctx, glb_policy, pick_args,
                                      false /* force_async */, target, wc_arg);
   } else {
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_DEBUG,
               "No RR policy in grpclb instance %p. Adding to grpclb's pending "
               "picks",
@@ -1242,7 +1242,7 @@ static void lb_call_on_retry_timer_locked(grpc_exec_ctx *exec_ctx, void *arg,
   glb_lb_policy *glb_policy = (glb_lb_policy *)arg;
   glb_policy->retry_timer_active = false;
   if (!glb_policy->shutting_down && error == GRPC_ERROR_NONE) {
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_INFO, "Restaring call to LB server (grpclb %p)",
               (void *)glb_policy);
     }
@@ -1264,7 +1264,7 @@ static void maybe_restart_lb_call(grpc_exec_ctx *exec_ctx,
     /* if we aren't shutting down, restart the LB client call after some time */
     grpc_millis next_try =
         grpc_backoff_step(exec_ctx, &glb_policy->lb_call_backoff_state);
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+    if (grpc_lb_glb_trace.enabled()) {
       gpr_log(GPR_DEBUG, "Connection to LB server lost (grpclb: %p)...",
               (void *)glb_policy);
       grpc_millis timeout = next_try - grpc_exec_ctx_now(exec_ctx);
@@ -1465,7 +1465,7 @@ static void query_for_backends_locked(grpc_exec_ctx *exec_ctx,
 
   lb_call_init_locked(exec_ctx, glb_policy);
 
-  if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+  if (grpc_lb_glb_trace.enabled()) {
     gpr_log(GPR_INFO,
             "Query for backends (grpclb: %p, lb_channel: %p, lb_call: %p)",
             (void *)glb_policy, (void *)glb_policy->lb_channel,
@@ -1557,7 +1557,7 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
         glb_policy->client_stats_report_interval = GPR_MAX(
             GPR_MS_PER_SEC, grpc_grpclb_duration_to_millis(
                                 &response->client_stats_report_interval));
-        if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+        if (grpc_lb_glb_trace.enabled()) {
           gpr_log(GPR_INFO,
                   "received initial LB response message; "
                   "client load reporting interval = %" PRIdPTR " milliseconds",
@@ -1569,7 +1569,7 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
         glb_policy->client_load_report_timer_pending = true;
         GRPC_LB_POLICY_WEAK_REF(&glb_policy->base, "client_load_report");
         schedule_next_client_load_report(exec_ctx, glb_policy);
-      } else if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+      } else if (grpc_lb_glb_trace.enabled()) {
         gpr_log(GPR_INFO,
                 "received initial LB response message; "
                 "client load reporting NOT enabled");
@@ -1581,7 +1581,7 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
           grpc_grpclb_response_parse_serverlist(response_slice);
       if (serverlist != NULL) {
         GPR_ASSERT(glb_policy->lb_call != NULL);
-        if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+        if (grpc_lb_glb_trace.enabled()) {
           gpr_log(GPR_INFO, "Serverlist with %lu servers received",
                   (unsigned long)serverlist->num_servers);
           for (size_t i = 0; i < serverlist->num_servers; ++i) {
@@ -1597,7 +1597,7 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
         if (serverlist->num_servers > 0) {
           if (grpc_grpclb_serverlist_equals(glb_policy->serverlist,
                                             serverlist)) {
-            if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+            if (grpc_lb_glb_trace.enabled()) {
               gpr_log(GPR_INFO,
                       "Incoming server list identical to current, ignoring.");
             }
@@ -1624,7 +1624,7 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
             rr_handover_locked(exec_ctx, glb_policy);
           }
         } else {
-          if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+          if (grpc_lb_glb_trace.enabled()) {
             gpr_log(GPR_INFO, "Received empty server list, ignoring.");
           }
           grpc_grpclb_destroy_serverlist(serverlist);
@@ -1668,7 +1668,7 @@ static void lb_on_fallback_timer_locked(grpc_exec_ctx *exec_ctx, void *arg,
    * actually runs, don't fall back. */
   if (glb_policy->serverlist == NULL) {
     if (!glb_policy->shutting_down && error == GRPC_ERROR_NONE) {
-      if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+      if (grpc_lb_glb_trace.enabled()) {
         gpr_log(GPR_INFO,
                 "Falling back to use backends from resolver (grpclb %p)",
                 (void *)glb_policy);
@@ -1685,7 +1685,7 @@ static void lb_on_server_status_received_locked(grpc_exec_ctx *exec_ctx,
                                                 void *arg, grpc_error *error) {
   glb_lb_policy *glb_policy = (glb_lb_policy *)arg;
   GPR_ASSERT(glb_policy->lb_call != NULL);
-  if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+  if (grpc_lb_glb_trace.enabled()) {
     char *status_details =
         grpc_slice_to_c_string(glb_policy->lb_call_status_details);
     gpr_log(GPR_INFO,
@@ -1869,7 +1869,7 @@ static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
   GPR_ASSERT(uri->path[0] != '\0');
   glb_policy->server_name =
       gpr_strdup(uri->path[0] == '/' ? uri->path + 1 : uri->path);
-  if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+  if (grpc_lb_glb_trace.enabled()) {
     gpr_log(GPR_INFO, "Will use '%s' as the server name for LB request.",
             glb_policy->server_name);
   }
@@ -1962,9 +1962,9 @@ static bool maybe_add_client_load_reporting_filter(
 
 extern "C" void grpc_lb_policy_grpclb_init() {
   grpc_register_lb_policy(grpc_glb_lb_factory_create());
-  grpc_register_tracer(&grpc_lb_glb_trace);
+
 #ifndef NDEBUG
-  grpc_register_tracer(&grpc_trace_lb_policy_refcount);
+
 #endif
   grpc_channel_init_register_stage(GRPC_CLIENT_SUBCHANNEL,
                                    GRPC_CHANNEL_INIT_BUILTIN_PRIORITY,

src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc

@@ -28,8 +28,7 @@
 #include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/transport/connectivity_state.h"
 
-grpc_tracer_flag grpc_lb_pick_first_trace =
-    GRPC_TRACER_INITIALIZER(false, "pick_first");
+grpc_core::TraceFlag grpc_lb_pick_first_trace(false, "pick_first");
 
 typedef struct pending_pick {
   struct pending_pick *next;
@@ -97,7 +96,7 @@ static void pf_destroy(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   gpr_free(p->subchannels);
   gpr_free(p->new_subchannels);
   gpr_free(p);
-  if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+  if (grpc_lb_pick_first_trace.enabled()) {
     gpr_log(GPR_DEBUG, "Pick First %p destroyed.", (void *)p);
   }
 }
@@ -273,7 +272,7 @@ static void stop_connectivity_watchers(grpc_exec_ctx *exec_ctx,
                                        pick_first_lb_policy *p) {
   if (p->num_subchannels > 0) {
     GPR_ASSERT(p->selected == NULL);
-    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+    if (grpc_lb_pick_first_trace.enabled()) {
       gpr_log(GPR_DEBUG, "Pick First %p unsubscribing from subchannel %p",
               (void *)p, (void *)p->subchannels[p->checking_subchannel]);
     }
@@ -282,7 +281,7 @@ static void stop_connectivity_watchers(grpc_exec_ctx *exec_ctx,
         &p->connectivity_changed);
     p->updating_subchannels = true;
   } else if (p->selected != NULL) {
-    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+    if (grpc_lb_pick_first_trace.enabled()) {
       gpr_log(GPR_DEBUG,
               "Pick First %p unsubscribing from selected subchannel %p",
               (void *)p, (void *)p->selected);
@@ -327,7 +326,7 @@ static void pf_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
     stop_connectivity_watchers(exec_ctx, p);
     return;
   }
-  if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+  if (grpc_lb_pick_first_trace.enabled()) {
     gpr_log(GPR_INFO, "Pick First %p received update with %lu addresses",
             (void *)p, (unsigned long)addresses->num_addresses);
   }
@@ -366,7 +365,7 @@ static void pf_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
       grpc_subchannel_key_destroy(exec_ctx, ith_sc_key);
       if (found_selected) {
         // The currently selected subchannel is in the update: we are done.
-        if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+        if (grpc_lb_pick_first_trace.enabled()) {
           gpr_log(GPR_INFO,
                   "Pick First %p found already selected subchannel %p amongst "
                   "updates. Update done.",
@@ -385,7 +384,7 @@ static void pf_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
   // steps were successful, the update can be considered done without any
   // interference (ie, no callbacks were scheduled).
   if (p->updating_selected || p->updating_subchannels) {
-    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+    if (grpc_lb_pick_first_trace.enabled()) {
       gpr_log(GPR_INFO,
               "Update already in progress for pick first %p. Deferring update.",
               (void *)p);
@@ -409,7 +408,7 @@ static void pf_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
   for (size_t i = 0; i < sc_args_count; i++) {
     grpc_subchannel *subchannel = grpc_client_channel_factory_create_subchannel(
         exec_ctx, args->client_channel_factory, &sc_args[i]);
-    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+    if (grpc_lb_pick_first_trace.enabled()) {
       char *address_uri =
           grpc_sockaddr_to_uri(&addresses->addresses[i].address);
       gpr_log(GPR_INFO,
@@ -463,7 +462,7 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
   grpc_subchannel *selected_subchannel;
   pending_pick *pp;
 
-  if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+  if (grpc_lb_pick_first_trace.enabled()) {
     gpr_log(
         GPR_DEBUG,
         "Pick First %p connectivity changed. Updating selected: %d; Updating "
@@ -478,7 +477,7 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
     GPR_ASSERT(p->selected != NULL);
     GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, p->selected,
                                     "pf_update_connectivity");
-    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+    if (grpc_lb_pick_first_trace.enabled()) {
       gpr_log(GPR_DEBUG, "Pick First %p unreffing selected subchannel %p",
               (void *)p, (void *)p->selected);
     }
@@ -495,7 +494,7 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
     for (size_t i = 0; i < p->num_subchannels; i++) {
       GRPC_SUBCHANNEL_UNREF(exec_ctx, p->subchannels[i],
                             "pf_update_connectivity");
-      if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+      if (grpc_lb_pick_first_trace.enabled()) {
         gpr_log(GPR_DEBUG, "Pick First %p unreffing subchannel %p", (void *)p,
                 (void *)p->subchannels[i]);
       }
@@ -568,7 +567,7 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
             grpc_subchannel_get_connected_subchannel(selected_subchannel),
             "picked_first");
 
-        if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+        if (grpc_lb_pick_first_trace.enabled()) {
           gpr_log(GPR_INFO,
                   "Pick First %p selected subchannel %p (connected %p)",
                   (void *)p, (void *)selected_subchannel, (void *)p->selected);
@@ -581,7 +580,7 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
         while ((pp = p->pending_picks)) {
           p->pending_picks = pp->next;
           *pp->target = GRPC_CONNECTED_SUBCHANNEL_REF(p->selected, "picked");
-          if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+          if (grpc_lb_pick_first_trace.enabled()) {
             gpr_log(GPR_INFO,
                     "Servicing pending pick with selected subchannel %p",
                     (void *)p->selected);
@@ -682,7 +681,7 @@ static grpc_lb_policy *create_pick_first(grpc_exec_ctx *exec_ctx,
                                          grpc_lb_policy_args *args) {
   GPR_ASSERT(args->client_channel_factory != NULL);
   pick_first_lb_policy *p = (pick_first_lb_policy *)gpr_zalloc(sizeof(*p));
-  if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+  if (grpc_lb_pick_first_trace.enabled()) {
     gpr_log(GPR_DEBUG, "Pick First %p created.", (void *)p);
   }
   pf_update_locked(exec_ctx, &p->base, args);
@@ -708,7 +707,6 @@ static grpc_lb_policy_factory *pick_first_lb_factory_create() {
 
 extern "C" void grpc_lb_policy_pick_first_init() {
   grpc_register_lb_policy(pick_first_lb_factory_create());
-  grpc_register_tracer(&grpc_lb_pick_first_trace);
 }
 
 extern "C" void grpc_lb_policy_pick_first_shutdown() {}

src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc

@@ -38,8 +38,7 @@
 #include "src/core/lib/transport/connectivity_state.h"
 #include "src/core/lib/transport/static_metadata.h"
 
-grpc_tracer_flag grpc_lb_round_robin_trace =
-    GRPC_TRACER_INITIALIZER(false, "round_robin");
+grpc_core::TraceFlag grpc_lb_round_robin_trace(false, "round_robin");
 
 /** List of entities waiting for a pick.
  *
@@ -152,7 +151,7 @@ static rr_subchannel_list *rr_subchannel_list_create(round_robin_lb_policy *p,
       (subchannel_data *)gpr_zalloc(sizeof(subchannel_data) * num_subchannels);
   subchannel_list->num_subchannels = num_subchannels;
   gpr_ref_init(&subchannel_list->refcount, 1);
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(GPR_INFO, "[RR %p] Created subchannel list %p for %lu subchannels",
             (void *)p, (void *)subchannel_list, (unsigned long)num_subchannels);
   }
@@ -162,7 +161,7 @@ static rr_subchannel_list *rr_subchannel_list_create(round_robin_lb_policy *p,
 static void rr_subchannel_list_destroy(grpc_exec_ctx *exec_ctx,
                                        rr_subchannel_list *subchannel_list) {
   GPR_ASSERT(subchannel_list->shutting_down);
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(GPR_INFO, "[RR %p] Destroying subchannel_list %p",
             (void *)subchannel_list->policy, (void *)subchannel_list);
   }
@@ -186,7 +185,7 @@ static void rr_subchannel_list_destroy(grpc_exec_ctx *exec_ctx,
 static void rr_subchannel_list_ref(rr_subchannel_list *subchannel_list,
                                    const char *reason) {
   gpr_ref_non_zero(&subchannel_list->refcount);
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     const gpr_atm count = gpr_atm_acq_load(&subchannel_list->refcount.count);
     gpr_log(GPR_INFO, "[RR %p] subchannel_list %p REF %lu->%lu (%s)",
             (void *)subchannel_list->policy, (void *)subchannel_list,
@@ -198,7 +197,7 @@ static void rr_subchannel_list_unref(grpc_exec_ctx *exec_ctx,
                                      rr_subchannel_list *subchannel_list,
                                      const char *reason) {
   const bool done = gpr_unref(&subchannel_list->refcount);
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     const gpr_atm count = gpr_atm_acq_load(&subchannel_list->refcount.count);
     gpr_log(GPR_INFO, "[RR %p] subchannel_list %p UNREF %lu->%lu (%s)",
             (void *)subchannel_list->policy, (void *)subchannel_list,
@@ -215,7 +214,7 @@ static void rr_subchannel_list_shutdown_and_unref(
     grpc_exec_ctx *exec_ctx, rr_subchannel_list *subchannel_list,
     const char *reason) {
   GPR_ASSERT(!subchannel_list->shutting_down);
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(GPR_DEBUG, "[RR %p] Shutting down subchannel_list %p (%s)",
             (void *)subchannel_list->policy, (void *)subchannel_list, reason);
   }
@@ -224,7 +223,7 @@ static void rr_subchannel_list_shutdown_and_unref(
   for (size_t i = 0; i < subchannel_list->num_subchannels; i++) {
     subchannel_data *sd = &subchannel_list->subchannels[i];
     if (sd->subchannel != NULL) {  // if subchannel isn't shutdown, unsubscribe.
-      if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+      if (grpc_lb_round_robin_trace.enabled()) {
         gpr_log(
             GPR_DEBUG,
             "[RR %p] Unsubscribing from subchannel %p as part of shutting down "
@@ -249,7 +248,7 @@ static void rr_subchannel_list_shutdown_and_unref(
 static size_t get_next_ready_subchannel_index_locked(
     const round_robin_lb_policy *p) {
   GPR_ASSERT(p->subchannel_list != NULL);
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(GPR_INFO,
             "[RR %p] getting next ready subchannel (out of %lu), "
             "last_ready_subchannel_index=%lu",
@@ -259,7 +258,7 @@ static size_t get_next_ready_subchannel_index_locked(
   for (size_t i = 0; i < p->subchannel_list->num_subchannels; ++i) {
     const size_t index = (i + p->last_ready_subchannel_index + 1) %
                          p->subchannel_list->num_subchannels;
-    if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+    if (grpc_lb_round_robin_trace.enabled()) {
       gpr_log(
           GPR_DEBUG,
           "[RR %p] checking subchannel %p, subchannel_list %p, index %lu: "
@@ -271,7 +270,7 @@ static size_t get_next_ready_subchannel_index_locked(
     }
     if (p->subchannel_list->subchannels[index].curr_connectivity_state ==
         GRPC_CHANNEL_READY) {
-      if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+      if (grpc_lb_round_robin_trace.enabled()) {
         gpr_log(GPR_DEBUG,
                 "[RR %p] found next ready subchannel (%p) at index %lu of "
                 "subchannel_list %p",
@@ -282,7 +281,7 @@ static size_t get_next_ready_subchannel_index_locked(
       return index;
     }
   }
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(GPR_DEBUG, "[RR %p] no subchannels in ready state", (void *)p);
   }
   return p->subchannel_list->num_subchannels;
@@ -293,7 +292,7 @@ static void update_last_ready_subchannel_index_locked(round_robin_lb_policy *p,
                                                       size_t last_ready_index) {
   GPR_ASSERT(last_ready_index < p->subchannel_list->num_subchannels);
   p->last_ready_subchannel_index = last_ready_index;
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(
         GPR_DEBUG,
         "[RR %p] setting last_ready_subchannel_index=%lu (SC %p, CSC %p)",
@@ -306,7 +305,7 @@ static void update_last_ready_subchannel_index_locked(round_robin_lb_policy *p,
 
 static void rr_destroy(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   round_robin_lb_policy *p = (round_robin_lb_policy *)pol;
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(GPR_DEBUG, "[RR %p] Destroying Round Robin policy at %p",
             (void *)pol, (void *)pol);
   }
@@ -317,7 +316,7 @@ static void rr_destroy(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
 
 static void rr_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   round_robin_lb_policy *p = (round_robin_lb_policy *)pol;
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(GPR_DEBUG, "[RR %p] Shutting down Round Robin policy at %p",
             (void *)pol, (void *)pol);
   }
@@ -424,7 +423,7 @@ static int rr_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                           grpc_closure *on_complete) {
   round_robin_lb_policy *p = (round_robin_lb_policy *)pol;
   GPR_ASSERT(!p->shutdown);
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(GPR_INFO, "[RR %p] Trying to pick", (void *)pol);
   }
   if (p->subchannel_list != NULL) {
@@ -438,7 +437,7 @@ static int rr_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
       if (user_data != NULL) {
         *user_data = sd->user_data;
       }
-      if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+      if (grpc_lb_round_robin_trace.enabled()) {
         gpr_log(
             GPR_DEBUG,
             "[RR %p] Picked target <-- Subchannel %p (connected %p) (sl %p, "
@@ -558,7 +557,7 @@ static void rr_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                            grpc_error *error) {
   subchannel_data *sd = (subchannel_data *)arg;
   round_robin_lb_policy *p = sd->subchannel_list->policy;
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(
         GPR_DEBUG,
         "[RR %p] connectivity changed for subchannel %p, subchannel_list %p: "
@@ -644,7 +643,7 @@ static void rr_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
         // for sds belonging to outdated subchannel lists.
         GPR_ASSERT(sd->subchannel_list == p->latest_pending_subchannel_list);
         GPR_ASSERT(!sd->subchannel_list->shutting_down);
-        if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+        if (grpc_lb_round_robin_trace.enabled()) {
           const unsigned long num_subchannels =
               p->subchannel_list != NULL
                   ? (unsigned long)p->subchannel_list->num_subchannels
@@ -684,7 +683,7 @@ static void rr_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
         if (pp->user_data != NULL) {
           *pp->user_data = selected->user_data;
         }
-        if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+        if (grpc_lb_round_robin_trace.enabled()) {
           gpr_log(GPR_DEBUG,
                   "[RR %p] Fulfilling pending pick. Target <-- subchannel %p "
                   "(subchannel_list %p, index %lu)",
@@ -774,7 +773,7 @@ static void rr_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
   }
   size_t subchannel_index = 0;
   if (p->latest_pending_subchannel_list != NULL && p->started_picking) {
-    if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+    if (grpc_lb_round_robin_trace.enabled()) {
       gpr_log(GPR_DEBUG,
               "[RR %p] Shutting down latest pending subchannel list %p, about "
               "to be replaced by newer latest %p",
@@ -816,7 +815,7 @@ static void rr_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
       GRPC_ERROR_UNREF(error);
       continue;
     }
-    if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+    if (grpc_lb_round_robin_trace.enabled()) {
       char *address_uri =
           grpc_sockaddr_to_uri(&addresses->addresses[i].address);
       gpr_log(
@@ -896,7 +895,7 @@ static grpc_lb_policy *round_robin_create(grpc_exec_ctx *exec_ctx,
   grpc_connectivity_state_init(&p->state_tracker, GRPC_CHANNEL_IDLE,
                                "round_robin");
   rr_update_locked(exec_ctx, &p->base, args);
-  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+  if (grpc_lb_round_robin_trace.enabled()) {
     gpr_log(GPR_DEBUG, "[RR %p] Created with %lu subchannels", (void *)p,
             (unsigned long)p->subchannel_list->num_subchannels);
   }
@@ -918,7 +917,6 @@ static grpc_lb_policy_factory *round_robin_lb_factory_create() {
 
 extern "C" void grpc_lb_policy_round_robin_init() {
   grpc_register_lb_policy(round_robin_lb_factory_create());
-  grpc_register_tracer(&grpc_lb_round_robin_trace);
 }
 
 extern "C" void grpc_lb_policy_round_robin_shutdown() {}

src/core/ext/filters/client_channel/resolver.cc

@@ -19,10 +19,8 @@
 #include "src/core/ext/filters/client_channel/resolver.h"
 #include "src/core/lib/iomgr/combiner.h"
 
-#ifndef NDEBUG
-grpc_tracer_flag grpc_trace_resolver_refcount =
-    GRPC_TRACER_INITIALIZER(false, "resolver_refcount");
-#endif
+grpc_core::DebugOnlyTraceFlag grpc_trace_resolver_refcount(false,
+                                                           "resolver_refcount");
 
 void grpc_resolver_init(grpc_resolver *resolver,
                         const grpc_resolver_vtable *vtable,
@@ -35,7 +33,7 @@ void grpc_resolver_init(grpc_resolver *resolver,
 #ifndef NDEBUG
 void grpc_resolver_ref(grpc_resolver *resolver, const char *file, int line,
                        const char *reason) {
-  if (GRPC_TRACER_ON(grpc_trace_resolver_refcount)) {
+  if (grpc_trace_resolver_refcount.enabled()) {
     gpr_atm old_refs = gpr_atm_no_barrier_load(&resolver->refs.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "RESOLVER:%p   ref %" PRIdPTR " -> %" PRIdPTR " %s", resolver,
@@ -50,7 +48,7 @@ void grpc_resolver_ref(grpc_resolver *resolver) {
 #ifndef NDEBUG
 void grpc_resolver_unref(grpc_exec_ctx *exec_ctx, grpc_resolver *resolver,
                          const char *file, int line, const char *reason) {
-  if (GRPC_TRACER_ON(grpc_trace_resolver_refcount)) {
+  if (grpc_trace_resolver_refcount.enabled()) {
     gpr_atm old_refs = gpr_atm_no_barrier_load(&resolver->refs.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "RESOLVER:%p unref %" PRIdPTR " -> %" PRIdPTR " %s", resolver,

src/core/ext/filters/client_channel/resolver.h

@@ -30,7 +30,7 @@ typedef struct grpc_resolver grpc_resolver;
 typedef struct grpc_resolver_vtable grpc_resolver_vtable;
 
 #ifndef NDEBUG
-extern grpc_tracer_flag grpc_trace_resolver_refcount;
+extern grpc_core::TraceFlag grpc_trace_resolver_refcount;
 #endif
 
 /** \a grpc_resolver provides \a grpc_channel_args objects to its caller */

src/core/ext/filters/client_channel/subchannel.cc

@@ -199,7 +199,7 @@ static gpr_atm ref_mutate(grpc_subchannel *c, gpr_atm delta,
   gpr_atm old_val = barrier ? gpr_atm_full_fetch_add(&c->ref_pair, delta)
                             : gpr_atm_no_barrier_fetch_add(&c->ref_pair, delta);
 #ifndef NDEBUG
-  if (GRPC_TRACER_ON(grpc_trace_stream_refcount)) {
+  if (grpc_trace_stream_refcount.enabled()) {
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "SUBCHANNEL: %p %12s 0x%" PRIxPTR " -> 0x%" PRIxPTR " [%s]", c,
             purpose, old_val, old_val + delta, reason);

src/core/ext/filters/http/http_filters_plugin.cc

@@ -65,7 +65,6 @@ static bool maybe_add_required_filter(grpc_exec_ctx *exec_ctx,
 }
 
 extern "C" void grpc_http_filters_init(void) {
-  grpc_register_tracer(&grpc_compression_trace);
   grpc_channel_init_register_stage(GRPC_CLIENT_SUBCHANNEL,
                                    GRPC_CHANNEL_INIT_BUILTIN_PRIORITY,
                                    maybe_add_optional_filter, &compress_filter);

src/core/ext/filters/http/message_compress/message_compress_filter.cc

@@ -243,7 +243,7 @@ static void finish_send_message(grpc_exec_ctx *exec_ctx,
   bool did_compress = grpc_msg_compress(exec_ctx, calld->compression_algorithm,
                                         &calld->slices, &tmp);
   if (did_compress) {
-    if (GRPC_TRACER_ON(grpc_compression_trace)) {
+    if (grpc_compression_trace.enabled()) {
       const char *algo_name;
       const size_t before_size = calld->slices.length;
       const size_t after_size = tmp.length;
@@ -257,7 +257,7 @@ static void finish_send_message(grpc_exec_ctx *exec_ctx,
     grpc_slice_buffer_swap(&calld->slices, &tmp);
     send_flags |= GRPC_WRITE_INTERNAL_COMPRESS;
   } else {
-    if (GRPC_TRACER_ON(grpc_compression_trace)) {
+    if (grpc_compression_trace.enabled()) {
       const char *algo_name;
       GPR_ASSERT(grpc_compression_algorithm_name(calld->compression_algorithm,
                                                  &algo_name));

src/core/ext/transport/chttp2/transport/chttp2_plugin.cc

@@ -21,11 +21,8 @@
 #include "src/core/lib/transport/metadata.h"
 
 extern "C" void grpc_chttp2_plugin_init(void) {
-  grpc_register_tracer(&grpc_http_trace);
-  grpc_register_tracer(&grpc_flowctl_trace);
-  grpc_register_tracer(&grpc_trace_http2_stream_state);
 #ifndef NDEBUG
-  grpc_register_tracer(&grpc_trace_chttp2_refcount);
+
 #endif
 }
 

src/core/ext/transport/chttp2/transport/chttp2_transport.cc

@@ -90,13 +90,11 @@ static int g_default_max_pings_without_data = DEFAULT_MAX_PINGS_BETWEEN_DATA;
 static int g_default_max_ping_strikes = DEFAULT_MAX_PING_STRIKES;
 
 #define MAX_CLIENT_STREAM_ID 0x7fffffffu
-grpc_tracer_flag grpc_http_trace = GRPC_TRACER_INITIALIZER(false, "http");
-grpc_tracer_flag grpc_flowctl_trace = GRPC_TRACER_INITIALIZER(false, "flowctl");
+grpc_core::TraceFlag grpc_http_trace(false, "http");
+grpc_core::TraceFlag grpc_flowctl_trace(false, "flowctl");
 
-#ifndef NDEBUG
-grpc_tracer_flag grpc_trace_chttp2_refcount =
-    GRPC_TRACER_INITIALIZER(false, "chttp2_refcount");
-#endif
+grpc_core::DebugOnlyTraceFlag grpc_trace_chttp2_refcount(false,
+                                                         "chttp2_refcount");
 
 /* forward declarations of various callbacks that we'll build closures around */
 static void write_action_begin_locked(grpc_exec_ctx *exec_ctx, void *t,
@@ -233,7 +231,7 @@ static void destruct_transport(grpc_exec_ctx *exec_ctx,
 void grpc_chttp2_unref_transport(grpc_exec_ctx *exec_ctx,
                                  grpc_chttp2_transport *t, const char *reason,
                                  const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_trace_chttp2_refcount)) {
+  if (grpc_trace_chttp2_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&t->refs.count);
     gpr_log(GPR_DEBUG, "chttp2:unref:%p %" PRIdPTR "->%" PRIdPTR " %s [%s:%d]",
             t, val, val - 1, reason, file, line);
@@ -244,7 +242,7 @@ void grpc_chttp2_unref_transport(grpc_exec_ctx *exec_ctx,
 
 void grpc_chttp2_ref_transport(grpc_chttp2_transport *t, const char *reason,
                                const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_trace_chttp2_refcount)) {
+  if (grpc_trace_chttp2_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&t->refs.count);
     gpr_log(GPR_DEBUG, "chttp2:  ref:%p %" PRIdPTR "->%" PRIdPTR " %s [%s:%d]",
             t, val, val + 1, reason, file, line);
@@ -1228,7 +1226,7 @@ void grpc_chttp2_complete_closure_step(grpc_exec_ctx *exec_ctx,
     return;
   }
   closure->next_data.scratch -= CLOSURE_BARRIER_FIRST_REF_BIT;
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     const char *errstr = grpc_error_string(error);
     gpr_log(
         GPR_DEBUG,
@@ -1387,7 +1385,7 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
 
   GRPC_STATS_INC_HTTP2_OP_BATCHES(exec_ctx);
 
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     char *str = grpc_transport_stream_op_batch_string(op);
     gpr_log(GPR_DEBUG, "perform_stream_op_locked: %s; on_complete = %p", str,
             op->on_complete);
@@ -1677,7 +1675,7 @@ static void perform_stream_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
     }
   }
 
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     char *str = grpc_transport_stream_op_batch_string(op);
     gpr_log(GPR_DEBUG, "perform_stream_op[s=%p]: %s", s, str);
     gpr_free(str);
@@ -2579,7 +2577,7 @@ static void schedule_bdp_ping_locked(grpc_exec_ctx *exec_ctx,
 static void start_bdp_ping_locked(grpc_exec_ctx *exec_ctx, void *tp,
                                   grpc_error *error) {
   grpc_chttp2_transport *t = (grpc_chttp2_transport *)tp;
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     gpr_log(GPR_DEBUG, "%s: Start BDP ping err=%s", t->peer_string,
             grpc_error_string(error));
   }
@@ -2593,7 +2591,7 @@ static void start_bdp_ping_locked(grpc_exec_ctx *exec_ctx, void *tp,
 static void finish_bdp_ping_locked(grpc_exec_ctx *exec_ctx, void *tp,
                                    grpc_error *error) {
   grpc_chttp2_transport *t = (grpc_chttp2_transport *)tp;
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     gpr_log(GPR_DEBUG, "%s: Complete BDP ping err=%s", t->peer_string,
             grpc_error_string(error));
   }
@@ -3093,7 +3091,7 @@ static void benign_reclaimer_locked(grpc_exec_ctx *exec_ctx, void *arg,
       grpc_chttp2_stream_map_size(&t->stream_map) == 0) {
     /* Channel with no active streams: send a goaway to try and make it
      * disconnect cleanly */
-    if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+    if (grpc_resource_quota_trace.enabled()) {
       gpr_log(GPR_DEBUG, "HTTP2: %s - send goaway to free memory",
               t->peer_string);
     }
@@ -3101,8 +3099,7 @@ static void benign_reclaimer_locked(grpc_exec_ctx *exec_ctx, void *arg,
                 grpc_error_set_int(
                     GRPC_ERROR_CREATE_FROM_STATIC_STRING("Buffers full"),
                     GRPC_ERROR_INT_HTTP2_ERROR, GRPC_HTTP2_ENHANCE_YOUR_CALM));
-  } else if (error == GRPC_ERROR_NONE &&
-             GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+  } else if (error == GRPC_ERROR_NONE && grpc_resource_quota_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "HTTP2: %s - skip benign reclamation, there are still %" PRIdPTR
             " streams",
@@ -3124,7 +3121,7 @@ static void destructive_reclaimer_locked(grpc_exec_ctx *exec_ctx, void *arg,
   if (error == GRPC_ERROR_NONE && n > 0) {
     grpc_chttp2_stream *s =
         (grpc_chttp2_stream *)grpc_chttp2_stream_map_rand(&t->stream_map);
-    if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+    if (grpc_resource_quota_trace.enabled()) {
       gpr_log(GPR_DEBUG, "HTTP2: %s - abandon stream id %d", t->peer_string,
               s->id);
     }

src/core/ext/transport/chttp2/transport/chttp2_transport.h

@@ -27,12 +27,12 @@
 extern "C" {
 #endif
 
-extern grpc_tracer_flag grpc_http_trace;
-extern grpc_tracer_flag grpc_flowctl_trace;
-extern grpc_tracer_flag grpc_trace_http2_stream_state;
+extern grpc_core::TraceFlag grpc_http_trace;
+extern grpc_core::TraceFlag grpc_flowctl_trace;
+extern grpc_core::TraceFlag grpc_trace_http2_stream_state;
 
 #ifndef NDEBUG
-extern grpc_tracer_flag grpc_trace_chttp2_refcount;
+extern grpc_core::TraceFlag grpc_trace_chttp2_refcount;
 #endif
 
 grpc_transport *grpc_create_chttp2_transport(

src/core/ext/transport/chttp2/transport/frame_settings.cc

@@ -204,20 +204,19 @@ grpc_error *grpc_chttp2_settings_parser_parse(grpc_exec_ctx *exec_ctx, void *p,
               parser->incoming_settings[id] != parser->value) {
             t->initial_window_update +=
                 (int64_t)parser->value - parser->incoming_settings[id];
-            if (GRPC_TRACER_ON(grpc_http_trace) ||
-                GRPC_TRACER_ON(grpc_flowctl_trace)) {
+            if (grpc_http_trace.enabled() || grpc_flowctl_trace.enabled()) {
               gpr_log(GPR_DEBUG, "%p[%s] adding %d for initial_window change",
                       t, t->is_client ? "cli" : "svr",
                       (int)t->initial_window_update);
             }
           }
           parser->incoming_settings[id] = parser->value;
-          if (GRPC_TRACER_ON(grpc_http_trace)) {
+          if (grpc_http_trace.enabled()) {
             gpr_log(GPR_DEBUG, "CHTTP2:%s:%s: got setting %s = %d",
                     t->is_client ? "CLI" : "SVR", t->peer_string, sp->name,
                     parser->value);
           }
-        } else if (GRPC_TRACER_ON(grpc_http_trace)) {
+        } else if (grpc_http_trace.enabled()) {
           gpr_log(GPR_ERROR, "CHTTP2: Ignoring unknown setting %d (value %d)",
                   parser->id, parser->value);
         }

src/core/ext/transport/chttp2/transport/hpack_encoder.cc

@@ -57,7 +57,7 @@ static const grpc_slice terminal_slice = {
     {{0, 0}}                  /* data.refcounted */
 };
 
-extern "C" grpc_tracer_flag grpc_http_trace;
+extern grpc_core::TraceFlag grpc_http_trace;
 
 typedef struct {
   int is_first_frame;
@@ -475,7 +475,7 @@ static void hpack_enc(grpc_exec_ctx *exec_ctx, grpc_chttp2_hpack_compressor *c,
         "Reserved header (colon-prefixed) happening after regular ones.");
   }
 
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     char *k = grpc_slice_to_c_string(GRPC_MDKEY(elem));
     char *v = NULL;
     if (grpc_is_binary_header(GRPC_MDKEY(elem))) {
@@ -670,7 +670,7 @@ void grpc_chttp2_hpack_compressor_set_max_table_size(
     }
   }
   c->advertise_table_size_change = 1;
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     gpr_log(GPR_DEBUG, "set max table size from encoder to %d", max_table_size);
   }
 }

src/core/ext/transport/chttp2/transport/hpack_parser.cc

@@ -650,7 +650,7 @@ static const uint8_t inverse_base64[256] = {
 /* emission helpers */
 static grpc_error *on_hdr(grpc_exec_ctx *exec_ctx, grpc_chttp2_hpack_parser *p,
                           grpc_mdelem md, int add_to_table) {
-  if (GRPC_TRACER_ON(grpc_http_trace) && !GRPC_MDELEM_IS_INTERNED(md)) {
+  if (grpc_http_trace.enabled() && !GRPC_MDELEM_IS_INTERNED(md)) {
     char *k = grpc_slice_to_c_string(GRPC_MDKEY(md));
     char *v = grpc_slice_to_c_string(GRPC_MDVALUE(md));
     gpr_log(
@@ -1041,7 +1041,7 @@ static grpc_error *parse_lithdr_nvridx_v(grpc_exec_ctx *exec_ctx,
 static grpc_error *finish_max_tbl_size(grpc_exec_ctx *exec_ctx,
                                        grpc_chttp2_hpack_parser *p,
                                        const uint8_t *cur, const uint8_t *end) {
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     gpr_log(GPR_INFO, "MAX TABLE SIZE: %d", p->index);
   }
   grpc_error *err =

src/core/ext/transport/chttp2/transport/hpack_table.cc

@@ -28,7 +28,7 @@
 #include "src/core/lib/debug/trace.h"
 #include "src/core/lib/support/murmur_hash.h"
 
-extern "C" grpc_tracer_flag grpc_http_trace;
+extern grpc_core::TraceFlag grpc_http_trace;
 
 static struct {
   const char *key;
@@ -246,7 +246,7 @@ void grpc_chttp2_hptbl_set_max_bytes(grpc_exec_ctx *exec_ctx,
   if (tbl->max_bytes == max_bytes) {
     return;
   }
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     gpr_log(GPR_DEBUG, "Update hpack parser max size to %d", max_bytes);
   }
   while (tbl->mem_used > max_bytes) {
@@ -270,7 +270,7 @@ grpc_error *grpc_chttp2_hptbl_set_current_table_size(grpc_exec_ctx *exec_ctx,
     gpr_free(msg);
     return err;
   }
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     gpr_log(GPR_DEBUG, "Update hpack parser table size to %d", bytes);
   }
   while (tbl->mem_used > bytes) {

src/core/ext/transport/chttp2/transport/internal.h

@@ -678,11 +678,11 @@ void grpc_chttp2_complete_closure_step(grpc_exec_ctx *exec_ctx,
 #define GRPC_CHTTP2_CLIENT_CONNECT_STRLEN \
   (sizeof(GRPC_CHTTP2_CLIENT_CONNECT_STRING) - 1)
 
-extern grpc_tracer_flag grpc_http_trace;
-extern grpc_tracer_flag grpc_flowctl_trace;
+extern grpc_core::TraceFlag grpc_http_trace;
+extern grpc_core::TraceFlag grpc_flowctl_trace;
 
 #define GRPC_CHTTP2_IF_TRACING(stmt) \
-  if (!(GRPC_TRACER_ON(grpc_http_trace))) \
+  if (!grpc_http_trace.enabled())    \
     ;                                \
   else                               \
   stmt

src/core/ext/transport/chttp2/transport/parsing.cc

@@ -310,7 +310,7 @@ static grpc_error *init_frame_parser(grpc_exec_ctx *exec_ctx,
     case GRPC_CHTTP2_FRAME_GOAWAY:
       return init_goaway_parser(exec_ctx, t);
     default:
-      if (GRPC_TRACER_ON(grpc_http_trace)) {
+      if (grpc_http_trace.enabled()) {
         gpr_log(GPR_ERROR, "Unknown frame type %02x", t->incoming_frame_type);
       }
       return init_skip_frame_parser(exec_ctx, t, 0);
@@ -415,7 +415,7 @@ static void on_initial_header(grpc_exec_ctx *exec_ctx, void *tp,
 
   GPR_ASSERT(s != NULL);
 
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     char *key = grpc_slice_to_c_string(GRPC_MDKEY(md));
     char *value =
         grpc_dump_slice(GRPC_MDVALUE(md), GPR_DUMP_HEX | GPR_DUMP_ASCII);
@@ -497,7 +497,7 @@ static void on_trailing_header(grpc_exec_ctx *exec_ctx, void *tp,
 
   GPR_ASSERT(s != NULL);
 
-  if (GRPC_TRACER_ON(grpc_http_trace)) {
+  if (grpc_http_trace.enabled()) {
     char *key = grpc_slice_to_c_string(GRPC_MDKEY(md));
     char *value =
         grpc_dump_slice(GRPC_MDVALUE(md), GPR_DUMP_HEX | GPR_DUMP_ASCII);
@@ -750,7 +750,7 @@ static grpc_error *parse_frame_slice(grpc_exec_ctx *exec_ctx,
   if (err == GRPC_ERROR_NONE) {
     return err;
   } else if (grpc_error_get_int(err, GRPC_ERROR_INT_STREAM_ID, NULL)) {
-    if (GRPC_TRACER_ON(grpc_http_trace)) {
+    if (grpc_http_trace.enabled()) {
       const char *msg = grpc_error_string(err);
       gpr_log(GPR_ERROR, "%s", msg);
     }

src/core/ext/transport/chttp2/transport/stream_lists.cc

@@ -39,8 +39,7 @@ static const char *stream_list_id_string(grpc_chttp2_stream_list_id id) {
   GPR_UNREACHABLE_CODE(return "unknown");
 }
 
-grpc_tracer_flag grpc_trace_http2_stream_state =
-    GRPC_TRACER_INITIALIZER(false, "http2_stream_state");
+grpc_core::TraceFlag grpc_trace_http2_stream_state(false, "http2_stream_state");
 
 /* core list management */
 
@@ -66,7 +65,7 @@ static bool stream_list_pop(grpc_chttp2_transport *t,
     s->included[id] = 0;
   }
   *stream = s;
-  if (s && GRPC_TRACER_ON(grpc_trace_http2_stream_state)) {
+  if (s && grpc_trace_http2_stream_state.enabled()) {
     gpr_log(GPR_DEBUG, "%p[%d][%s]: pop from %s", t, s->id,
             t->is_client ? "cli" : "svr", stream_list_id_string(id));
   }
@@ -88,7 +87,7 @@ static void stream_list_remove(grpc_chttp2_transport *t, grpc_chttp2_stream *s,
   } else {
     t->lists[id].tail = s->links[id].prev;
   }
-  if (GRPC_TRACER_ON(grpc_trace_http2_stream_state)) {
+  if (grpc_trace_http2_stream_state.enabled()) {
     gpr_log(GPR_DEBUG, "%p[%d][%s]: remove from %s", t, s->id,
             t->is_client ? "cli" : "svr", stream_list_id_string(id));
   }
@@ -120,7 +119,7 @@ static void stream_list_add_tail(grpc_chttp2_transport *t,
   }
   t->lists[id].tail = s;
   s->included[id] = 1;
-  if (GRPC_TRACER_ON(grpc_trace_http2_stream_state)) {
+  if (grpc_trace_http2_stream_state.enabled()) {
     gpr_log(GPR_DEBUG, "%p[%d][%s]: add to %s", t, s->id,
             t->is_client ? "cli" : "svr", stream_list_id_string(id));
   }

src/core/ext/transport/chttp2/transport/writing.cc

@@ -51,8 +51,7 @@ static void maybe_initiate_ping(grpc_exec_ctx *exec_ctx,
   }
   if (!grpc_closure_list_empty(pq->lists[GRPC_CHTTP2_PCL_INFLIGHT])) {
     /* ping already in-flight: wait */
-    if (GRPC_TRACER_ON(grpc_http_trace) ||
-        GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+    if (grpc_http_trace.enabled() || grpc_bdp_estimator_trace.enabled()) {
       gpr_log(GPR_DEBUG, "%s: Ping delayed [%p]: already pinging",
               t->is_client ? "CLIENT" : "SERVER", t->peer_string);
     }
@@ -61,8 +60,7 @@ static void maybe_initiate_ping(grpc_exec_ctx *exec_ctx,
   if (t->ping_state.pings_before_data_required == 0 &&
       t->ping_policy.max_pings_without_data != 0) {
     /* need to receive something of substance before sending a ping again */
-    if (GRPC_TRACER_ON(grpc_http_trace) ||
-        GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+    if (grpc_http_trace.enabled() || grpc_bdp_estimator_trace.enabled()) {
       gpr_log(GPR_DEBUG, "%s: Ping delayed [%p]: too many recent pings: %d/%d",
               t->is_client ? "CLIENT" : "SERVER", t->peer_string,
               t->ping_state.pings_before_data_required,
@@ -81,8 +79,7 @@ static void maybe_initiate_ping(grpc_exec_ctx *exec_ctx,
   }
   if (next_allowed_ping > now) {
     /* not enough elapsed time between successive pings */
-    if (GRPC_TRACER_ON(grpc_http_trace) ||
-        GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+    if (grpc_http_trace.enabled() || grpc_bdp_estimator_trace.enabled()) {
       gpr_log(GPR_DEBUG,
               "%s: Ping delayed [%p]: not enough time elapsed since last ping",
               t->is_client ? "CLIENT" : "SERVER", t->peer_string);
@@ -103,8 +100,7 @@ static void maybe_initiate_ping(grpc_exec_ctx *exec_ctx,
                         grpc_chttp2_ping_create(false, pq->inflight_id));
   GRPC_STATS_INC_HTTP2_PINGS_SENT(exec_ctx);
   t->ping_state.last_ping_sent_time = now;
-  if (GRPC_TRACER_ON(grpc_http_trace) ||
-      GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+  if (grpc_http_trace.enabled() || grpc_bdp_estimator_trace.enabled()) {
     gpr_log(GPR_DEBUG, "%s: Ping sent [%p]: %d/%d",
             t->is_client ? "CLIENT" : "SERVER", t->peer_string,
             t->ping_state.pings_before_data_required,

src/core/ext/transport/inproc/inproc_plugin.cc

@@ -19,12 +19,9 @@
 #include "src/core/ext/transport/inproc/inproc_transport.h"
 #include "src/core/lib/debug/trace.h"
 
-grpc_tracer_flag grpc_inproc_trace = GRPC_TRACER_INITIALIZER(false, "inproc");
+grpc_core::TraceFlag grpc_inproc_trace(false, "inproc");
 
-extern "C" void grpc_inproc_plugin_init(void) {
-  grpc_register_tracer(&grpc_inproc_trace);
-  grpc_inproc_transport_init();
-}
+extern "C" void grpc_inproc_plugin_init(void) { grpc_inproc_transport_init(); }
 
 extern "C" void grpc_inproc_plugin_shutdown(void) {
   grpc_inproc_transport_shutdown();

src/core/ext/transport/inproc/inproc_transport.cc

@@ -34,7 +34,7 @@
 
 #define INPROC_LOG(...)                                    \
   do {                                                     \
-    if (GRPC_TRACER_ON(grpc_inproc_trace)) gpr_log(__VA_ARGS__); \
+    if (grpc_inproc_trace.enabled()) gpr_log(__VA_ARGS__); \
   } while (0)
 
 static grpc_slice g_empty_slice;
@@ -199,7 +199,7 @@ static grpc_error *fill_in_metadata(grpc_exec_ctx *exec_ctx, inproc_stream *s,
                                     const grpc_metadata_batch *metadata,
                                     uint32_t flags, grpc_metadata_batch *out_md,
                                     uint32_t *outflags, bool *markfilled) {
-  if (GRPC_TRACER_ON(grpc_inproc_trace)) {
+  if (grpc_inproc_trace.enabled()) {
     log_metadata(metadata, s->t->is_client, outflags != NULL);
   }
 
@@ -870,7 +870,7 @@ static void perform_stream_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   gpr_mu *mu = &s->t->mu->mu;  // save aside in case s gets closed
   gpr_mu_lock(mu);
 
-  if (GRPC_TRACER_ON(grpc_inproc_trace)) {
+  if (grpc_inproc_trace.enabled()) {
     if (op->send_initial_metadata) {
       log_metadata(op->payload->send_initial_metadata.send_initial_metadata,
                    s->t->is_client, true);

src/core/ext/transport/inproc/inproc_transport.h

@@ -29,7 +29,7 @@ grpc_channel *grpc_inproc_channel_create(grpc_server *server,
                                          grpc_channel_args *args,
                                          void *reserved);
 
-extern grpc_tracer_flag grpc_inproc_trace;
+extern grpc_core::TraceFlag grpc_inproc_trace;
 
 void grpc_inproc_transport_init(void);
 void grpc_inproc_transport_shutdown(void);

src/core/lib/channel/channel_stack.cc

@@ -23,7 +23,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-grpc_tracer_flag grpc_trace_channel = GRPC_TRACER_INITIALIZER(false, "channel");
+grpc_core::TraceFlag grpc_trace_channel(false, "channel");
 
 /* Memory layouts.
 

src/core/lib/channel/channel_stack.h

@@ -285,10 +285,10 @@ void grpc_call_log_op(const char *file, int line, gpr_log_severity severity,
                       grpc_call_element *elem,
                       grpc_transport_stream_op_batch *op);
 
-extern grpc_tracer_flag grpc_trace_channel;
+extern grpc_core::TraceFlag grpc_trace_channel;
 
 #define GRPC_CALL_LOG_OP(sev, elem, op) \
-  if (GRPC_TRACER_ON(grpc_trace_channel)) grpc_call_log_op(sev, elem, op)
+  if (grpc_trace_channel.enabled()) grpc_call_log_op(sev, elem, op)
 
 #ifdef __cplusplus
 }

src/core/lib/channel/channel_stack_builder.cc

@@ -23,8 +23,8 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
 
-grpc_tracer_flag grpc_trace_channel_stack_builder =
-    GRPC_TRACER_INITIALIZER(false, "channel_stack_builder");
+grpc_core::TraceFlag grpc_trace_channel_stack_builder(false,
+                                                   "channel_stack_builder");
 
 typedef struct filter_node {
   struct filter_node *next;

src/core/lib/channel/channel_stack_builder.h

@@ -160,7 +160,7 @@ grpc_error *grpc_channel_stack_builder_finish(
 void grpc_channel_stack_builder_destroy(grpc_exec_ctx *exec_ctx,
                                         grpc_channel_stack_builder *builder);
 
-extern grpc_tracer_flag grpc_trace_channel_stack_builder;
+extern grpc_core::TraceFlag grpc_trace_channel_stack_builder;
 
 #ifdef __cplusplus
 }

src/core/lib/debug/trace.cc

@@ -27,26 +27,53 @@
 
 int grpc_tracer_set_enabled(const char *name, int enabled);
 
-typedef struct tracer {
-  grpc_tracer_flag *flag;
-  struct tracer *next;
-} tracer;
-static tracer *tracers;
-
-#ifdef GRPC_THREADSAFE_TRACER
-#define TRACER_SET(flag, on) gpr_atm_no_barrier_store(&(flag).value, (on))
-#else
-#define TRACER_SET(flag, on) (flag).value = (on)
-#endif
-
-void grpc_register_tracer(grpc_tracer_flag *flag) {
-  tracer *t = (tracer *)gpr_malloc(sizeof(*t));
-  t->flag = flag;
-  t->next = tracers;
-  TRACER_SET(*flag, false);
-  tracers = t;
+namespace grpc_core {
+
+TraceFlag::TraceFlag(bool default_enabled, const char *name)
+    : next_tracer_(root_tracer_), name_(name), value_(default_enabled) {
+  root_tracer_ = this;
+}
+
+void TraceFlag::List() {
+  gpr_log(GPR_DEBUG, "available tracers:");
+  TraceFlag *t;
+  for (t = root_tracer_; t != nullptr; t = t->next_tracer_) {
+    gpr_log(GPR_DEBUG, "\t%s", t->name_);
+  }
+}
+
+bool TraceFlag::Set(const char *name, bool enabled) {
+  TraceFlag *t;
+  if (0 == strcmp(name, "all")) {
+    for (t = root_tracer_; t; t = t->next_tracer_) {
+      t->set_enabled(enabled);
+    }
+  } else if (0 == strcmp(name, "list_tracers")) {
+    List();
+  } else if (0 == strcmp(name, "refcount")) {
+    for (t = root_tracer_; t; t = t->next_tracer_) {
+      if (strstr(t->name_, "refcount") != NULL) {
+        t->set_enabled(enabled);
+      }
+    }
+  } else {
+    bool found = false;
+    for (t = root_tracer_; t; t = t->next_tracer_) {
+      if (0 == strcmp(name, t->name_)) {
+        t->set_enabled(enabled);
+        found = true;
+      }
+    }
+    if (!found) {
+      gpr_log(GPR_ERROR, "Unknown trace var: '%s'", name);
+      return false; /* early return */
+    }
+  }
+  return true;
 }
 
+}  // namespace grpc_core
+
 static void add(const char *beg, const char *end, char ***ss, size_t *ns) {
   size_t n = *ns;
   size_t np = n + 1;
@@ -80,9 +107,9 @@ static void parse(const char *s) {
 
   for (i = 0; i < nstrings; i++) {
     if (strings[i][0] == '-') {
-      grpc_tracer_set_enabled(strings[i] + 1, 0);
+      grpc_core::TraceFlag::Set(strings[i] + 1, false);
     } else {
-      grpc_tracer_set_enabled(strings[i], 1);
+      grpc_core::TraceFlag::Set(strings[i], true);
     }
   }
 
@@ -92,14 +119,6 @@ static void parse(const char *s) {
   gpr_free(strings);
 }
 
-static void list_tracers() {
-  gpr_log(GPR_DEBUG, "available tracers:");
-  tracer *t;
-  for (t = tracers; t; t = t->next) {
-    gpr_log(GPR_DEBUG, "\t%s", t->flag->name);
-  }
-}
-
 void grpc_tracer_init(const char *env_var) {
   char *e = gpr_getenv(env_var);
   if (e != NULL) {
@@ -108,40 +127,8 @@ void grpc_tracer_init(const char *env_var) {
   }
 }
 
-void grpc_tracer_shutdown(void) {
-  while (tracers) {
-    tracer *t = tracers;
-    tracers = t->next;
-    gpr_free(t);
-  }
-}
+void grpc_tracer_shutdown(void) {}
 
 int grpc_tracer_set_enabled(const char *name, int enabled) {
-  tracer *t;
-  if (0 == strcmp(name, "all")) {
-    for (t = tracers; t; t = t->next) {
-      TRACER_SET(*t->flag, enabled);
-    }
-  } else if (0 == strcmp(name, "list_tracers")) {
-    list_tracers();
-  } else if (0 == strcmp(name, "refcount")) {
-    for (t = tracers; t; t = t->next) {
-      if (strstr(t->flag->name, "refcount") != NULL) {
-        TRACER_SET(*t->flag, enabled);
-      }
-    }
-  } else {
-    int found = 0;
-    for (t = tracers; t; t = t->next) {
-      if (0 == strcmp(name, t->flag->name)) {
-        TRACER_SET(*t->flag, enabled);
-        found = 1;
-      }
-    }
-    if (!found) {
-      gpr_log(GPR_ERROR, "Unknown trace var: '%s'", name);
-      return 0; /* early return */
-    }
-  }
-  return 1;
+  return grpc_core::TraceFlag::Set(name, enabled != 0);
 }

src/core/lib/debug/trace.h

@@ -27,37 +27,71 @@
 extern "C" {
 #endif
 
+void grpc_tracer_init(const char *env_var_name);
+void grpc_tracer_shutdown(void);
+
+#ifdef __cplusplus
+}
+#endif
+
 #if defined(__has_feature)
 #if __has_feature(thread_sanitizer)
 #define GRPC_THREADSAFE_TRACER
 #endif
 #endif
 
-typedef struct {
+#ifdef __cplusplus
+
+namespace grpc_core {
+
+class TraceFlag {
+ public:
+  TraceFlag(bool default_enabled, const char *name);
+  ~TraceFlag();
+
+  static bool Set(const char *tracer, bool enabled);
+
+  bool enabled() {
 #ifdef GRPC_THREADSAFE_TRACER
-  gpr_atm value;
+    gpr_atm_no_barrier_load(&value_) != 0
 #else
-  bool value;
+    return value_;
 #endif
-  const char *name;
-} grpc_tracer_flag;
+  }
 
+ private:
+  static void List();
+
+  void set_enabled(bool enabled) {
 #ifdef GRPC_THREADSAFE_TRACER
-#define GRPC_TRACER_ON(flag) (gpr_atm_no_barrier_load(&(flag).value) != 0)
-#define GRPC_TRACER_INITIALIZER(on, name) \
-  { (gpr_atm)(on), (name) }
+    gpr_atm_no_barrier_store(&value, enabled);
 #else
-#define GRPC_TRACER_ON(flag) ((flag).value)
-#define GRPC_TRACER_INITIALIZER(on, name) \
-  { (on), (name) }
+    value_ = enabled;
 #endif
+  }
 
-void grpc_register_tracer(grpc_tracer_flag *flag);
-void grpc_tracer_init(const char *env_var_name);
-void grpc_tracer_shutdown(void);
+  static TraceFlag *root_tracer_;
+  TraceFlag *next_tracer_;
+  const char *const name_;
+#ifdef GRPC_THREADSAFE_TRACER
+  gpr_atm value_;
+#else
+  bool value_;
+#endif
+};
 
-#ifdef __cplusplus
-}
+#ifndef NDEBUG
+typedef TraceFlag DebugOnlyTraceFlag;
+#else
+class DebugOnlyTraceFlag {
+ public:
+  DebugOnlyTraceFlag(bool default_enabled, const char *name) {}
+  bool enabled() { return false; }
+};
 #endif
 
+}  // namespace grpc_core
+
+#endif  // __cplusplus
+
 #endif /* GRPC_CORE_LIB_DEBUG_TRACE_H */

src/core/lib/http/parser.cc

@@ -25,7 +25,7 @@
 #include <grpc/support/log.h>
 #include <grpc/support/useful.h>
 
-grpc_tracer_flag grpc_http1_trace = GRPC_TRACER_INITIALIZER(false, "http1");
+grpc_core::TraceFlag grpc_http1_trace(false, "http1");
 
 static char *buf2str(void *buffer, size_t length) {
   char *out = (char *)gpr_malloc(length + 1);
@@ -294,7 +294,7 @@ static grpc_error *addbyte(grpc_http_parser *parser, uint8_t byte,
     case GRPC_HTTP_FIRST_LINE:
     case GRPC_HTTP_HEADERS:
       if (parser->cur_line_length >= GRPC_HTTP_PARSER_MAX_HEADER_LENGTH) {
-        if (GRPC_TRACER_ON(grpc_http1_trace))
+        if (grpc_http1_trace.enabled())
           gpr_log(GPR_ERROR, "HTTP header max line length (%d) exceeded",
                   GRPC_HTTP_PARSER_MAX_HEADER_LENGTH);
         return GRPC_ERROR_CREATE_FROM_STATIC_STRING(

src/core/lib/http/parser.h

@@ -111,7 +111,7 @@ grpc_error *grpc_http_parser_eof(grpc_http_parser *parser);
 void grpc_http_request_destroy(grpc_http_request *request);
 void grpc_http_response_destroy(grpc_http_response *response);
 
-extern grpc_tracer_flag grpc_http1_trace;
+extern grpc_core::TraceFlag grpc_http1_trace;
 
 #ifdef __cplusplus
 }

src/core/lib/iomgr/call_combiner.cc

@@ -24,8 +24,7 @@
 #include "src/core/lib/debug/stats.h"
 #include "src/core/lib/profiling/timers.h"
 
-grpc_tracer_flag grpc_call_combiner_trace =
-    GRPC_TRACER_INITIALIZER(false, "call_combiner");
+grpc_core::TraceFlag grpc_call_combiner_trace(false, "call_combiner");
 
 static grpc_error* decode_cancel_state_error(gpr_atm cancel_state) {
   if (cancel_state & 1) {
@@ -63,7 +62,7 @@ void grpc_call_combiner_start(grpc_exec_ctx* exec_ctx,
                               grpc_error* error DEBUG_ARGS,
                               const char* reason) {
   GPR_TIMER_BEGIN("call_combiner_start", 0);
-  if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+  if (grpc_call_combiner_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "==> grpc_call_combiner_start() [%p] closure=%p [" DEBUG_FMT_STR
             "%s] error=%s",
@@ -72,7 +71,7 @@ void grpc_call_combiner_start(grpc_exec_ctx* exec_ctx,
   }
   size_t prev_size =
       (size_t)gpr_atm_full_fetch_add(&call_combiner->size, (gpr_atm)1);
-  if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+  if (grpc_call_combiner_trace.enabled()) {
     gpr_log(GPR_DEBUG, "  size: %" PRIdPTR " -> %" PRIdPTR, prev_size,
             prev_size + 1);
   }
@@ -80,13 +79,13 @@ void grpc_call_combiner_start(grpc_exec_ctx* exec_ctx,
   if (prev_size == 0) {
     GRPC_STATS_INC_CALL_COMBINER_LOCKS_INITIATED(exec_ctx);
     GPR_TIMER_MARK("call_combiner_initiate", 0);
-    if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+    if (grpc_call_combiner_trace.enabled()) {
       gpr_log(GPR_DEBUG, "  EXECUTING IMMEDIATELY");
     }
     // Queue was empty, so execute this closure immediately.
     GRPC_CLOSURE_SCHED(exec_ctx, closure, error);
   } else {
-    if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+    if (grpc_call_combiner_trace.enabled()) {
       gpr_log(GPR_INFO, "  QUEUING");
     }
     // Queue was not empty, so add closure to queue.
@@ -100,21 +99,21 @@ void grpc_call_combiner_stop(grpc_exec_ctx* exec_ctx,
                              grpc_call_combiner* call_combiner DEBUG_ARGS,
                              const char* reason) {
   GPR_TIMER_BEGIN("call_combiner_stop", 0);
-  if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+  if (grpc_call_combiner_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "==> grpc_call_combiner_stop() [%p] [" DEBUG_FMT_STR "%s]",
             call_combiner DEBUG_FMT_ARGS, reason);
   }
   size_t prev_size =
       (size_t)gpr_atm_full_fetch_add(&call_combiner->size, (gpr_atm)-1);
-  if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+  if (grpc_call_combiner_trace.enabled()) {
     gpr_log(GPR_DEBUG, "  size: %" PRIdPTR " -> %" PRIdPTR, prev_size,
             prev_size - 1);
   }
   GPR_ASSERT(prev_size >= 1);
   if (prev_size > 1) {
     while (true) {
-      if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+      if (grpc_call_combiner_trace.enabled()) {
         gpr_log(GPR_DEBUG, "  checking queue");
       }
       bool empty;
@@ -123,19 +122,19 @@ void grpc_call_combiner_stop(grpc_exec_ctx* exec_ctx,
       if (closure == NULL) {
         // This can happen either due to a race condition within the mpscq
         // code or because of a race with grpc_call_combiner_start().
-        if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+        if (grpc_call_combiner_trace.enabled()) {
           gpr_log(GPR_DEBUG, "  queue returned no result; checking again");
         }
         continue;
       }
-      if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+      if (grpc_call_combiner_trace.enabled()) {
         gpr_log(GPR_DEBUG, "  EXECUTING FROM QUEUE: closure=%p error=%s",
                 closure, grpc_error_string(closure->error_data.error));
       }
       GRPC_CLOSURE_SCHED(exec_ctx, closure, closure->error_data.error);
       break;
     }
-  } else if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+  } else if (grpc_call_combiner_trace.enabled()) {
     gpr_log(GPR_DEBUG, "  queue empty");
   }
   GPR_TIMER_END("call_combiner_stop", 0);
@@ -152,7 +151,7 @@ void grpc_call_combiner_set_notify_on_cancel(grpc_exec_ctx* exec_ctx,
     // If error is set, invoke the cancellation closure immediately.
     // Otherwise, store the new closure.
     if (original_error != GRPC_ERROR_NONE) {
-      if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+      if (grpc_call_combiner_trace.enabled()) {
         gpr_log(GPR_DEBUG,
                 "call_combiner=%p: scheduling notify_on_cancel callback=%p "
                 "for pre-existing cancellation",
@@ -163,7 +162,7 @@ void grpc_call_combiner_set_notify_on_cancel(grpc_exec_ctx* exec_ctx,
     } else {
       if (gpr_atm_full_cas(&call_combiner->cancel_state, original_state,
                            (gpr_atm)closure)) {
-        if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+        if (grpc_call_combiner_trace.enabled()) {
           gpr_log(GPR_DEBUG, "call_combiner=%p: setting notify_on_cancel=%p",
                   call_combiner, closure);
         }
@@ -172,7 +171,7 @@ void grpc_call_combiner_set_notify_on_cancel(grpc_exec_ctx* exec_ctx,
         // up any resources they may be holding for the callback.
         if (original_state != 0) {
           closure = (grpc_closure*)original_state;
-          if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+          if (grpc_call_combiner_trace.enabled()) {
             gpr_log(GPR_DEBUG,
                     "call_combiner=%p: scheduling old cancel callback=%p",
                     call_combiner, closure);
@@ -201,7 +200,7 @@ void grpc_call_combiner_cancel(grpc_exec_ctx* exec_ctx,
                          encode_cancel_state_error(error))) {
       if (original_state != 0) {
         grpc_closure* notify_on_cancel = (grpc_closure*)original_state;
-        if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
+        if (grpc_call_combiner_trace.enabled()) {
           gpr_log(GPR_DEBUG,
                   "call_combiner=%p: scheduling notify_on_cancel callback=%p",
                   call_combiner, notify_on_cancel);

src/core/lib/iomgr/call_combiner.h

@@ -40,7 +40,7 @@ extern "C" {
 // when it is done with the action that was kicked off by the original
 // callback.
 
-extern grpc_tracer_flag grpc_call_combiner_trace;
+extern grpc_core::TraceFlag grpc_call_combiner_trace;
 
 typedef struct {
   gpr_atm size;  // size_t, num closures in queue or currently executing

src/core/lib/iomgr/closure.cc

@@ -24,9 +24,7 @@
 
 #include "src/core/lib/profiling/timers.h"
 
-#ifndef NDEBUG
-grpc_tracer_flag grpc_trace_closure = GRPC_TRACER_INITIALIZER(false, "closure");
-#endif
+grpc_core::DebugOnlyTraceFlag grpc_trace_closure(false, "closure");
 
 #ifndef NDEBUG
 grpc_closure *grpc_closure_init(const char *file, int line,

src/core/lib/iomgr/closure.h

@@ -34,7 +34,7 @@ struct grpc_closure;
 typedef struct grpc_closure grpc_closure;
 
 #ifndef NDEBUG
-extern grpc_tracer_flag grpc_trace_closure;
+extern grpc_core::TraceFlag grpc_trace_closure;
 #endif
 
 typedef struct grpc_closure_list {

src/core/lib/iomgr/combiner.cc

@@ -29,12 +29,11 @@
 #include "src/core/lib/iomgr/executor.h"
 #include "src/core/lib/profiling/timers.h"
 
-grpc_tracer_flag grpc_combiner_trace =
-    GRPC_TRACER_INITIALIZER(false, "combiner");
+grpc_core::TraceFlag grpc_combiner_trace(false, "combiner");
 
 #define GRPC_COMBINER_TRACE(fn)          \
   do {                                   \
-    if (GRPC_TRACER_ON(grpc_combiner_trace)) { \
+    if (grpc_combiner_trace.enabled()) { \
       fn;                                \
     }                                    \
   } while (0)
@@ -106,7 +105,7 @@ static void start_destroy(grpc_exec_ctx *exec_ctx, grpc_combiner *lock) {
 
 #ifndef NDEBUG
 #define GRPC_COMBINER_DEBUG_SPAM(op, delta)                                \
-  if (GRPC_TRACER_ON(grpc_combiner_trace)) {                               \
+  if (grpc_combiner_trace.enabled()) {                                     \
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,                            \
             "C:%p %s %" PRIdPTR " --> %" PRIdPTR " %s", lock, (op),        \
             gpr_atm_no_barrier_load(&lock->refs.count),                    \

src/core/lib/iomgr/combiner.h

@@ -65,7 +65,7 @@ grpc_closure_scheduler *grpc_combiner_finally_scheduler(grpc_combiner *lock);
 
 bool grpc_combiner_continue_exec_ctx(grpc_exec_ctx *exec_ctx);
 
-extern grpc_tracer_flag grpc_combiner_trace;
+extern grpc_core::TraceFlag grpc_combiner_trace;
 
 #ifdef __cplusplus
 }

src/core/lib/iomgr/error.cc

@@ -37,10 +37,8 @@
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/slice/slice_internal.h"
 
-#ifndef NDEBUG
-grpc_tracer_flag grpc_trace_error_refcount =
-    GRPC_TRACER_INITIALIZER(false, "error_refcount");
-#endif
+grpc_core::DebugOnlyTraceFlag grpc_trace_error_refcount(false,
+                                                        "error_refcount");
 
 static const char *error_int_name(grpc_error_ints key) {
   switch (key) {
@@ -130,7 +128,7 @@ bool grpc_error_is_special(grpc_error *err) {
 #ifndef NDEBUG
 grpc_error *grpc_error_ref(grpc_error *err, const char *file, int line) {
   if (grpc_error_is_special(err)) return err;
-  if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+  if (grpc_trace_error_refcount.enabled()) {
     gpr_log(GPR_DEBUG, "%p: %" PRIdPTR " -> %" PRIdPTR " [%s:%d]", err,
             gpr_atm_no_barrier_load(&err->atomics.refs.count),
             gpr_atm_no_barrier_load(&err->atomics.refs.count) + 1, file, line);
@@ -183,7 +181,7 @@ static void error_destroy(grpc_error *err) {
 #ifndef NDEBUG
 void grpc_error_unref(grpc_error *err, const char *file, int line) {
   if (grpc_error_is_special(err)) return;
-  if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+  if (grpc_trace_error_refcount.enabled()) {
     gpr_log(GPR_DEBUG, "%p: %" PRIdPTR " -> %" PRIdPTR " [%s:%d]", err,
             gpr_atm_no_barrier_load(&err->atomics.refs.count),
             gpr_atm_no_barrier_load(&err->atomics.refs.count) - 1, file, line);
@@ -216,7 +214,7 @@ static uint8_t get_placement(grpc_error **err, size_t size) {
     *err = (grpc_error *)gpr_realloc(
         *err, sizeof(grpc_error) + (*err)->arena_capacity * sizeof(intptr_t));
 #ifndef NDEBUG
-    if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+    if (grpc_trace_error_refcount.enabled()) {
       if (*err != orig) {
         gpr_log(GPR_DEBUG, "realloc %p -> %p", orig, *err);
       }
@@ -329,7 +327,7 @@ grpc_error *grpc_error_create(const char *file, int line, grpc_slice desc,
     return GRPC_ERROR_OOM;
   }
 #ifndef NDEBUG
-  if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+  if (grpc_trace_error_refcount.enabled()) {
     gpr_log(GPR_DEBUG, "%p create [%s:%d]", err, file, line);
   }
 #endif
@@ -411,7 +409,7 @@ static grpc_error *copy_error_and_unref(grpc_error *in) {
     out = (grpc_error *)gpr_malloc(sizeof(*in) +
                                    new_arena_capacity * sizeof(intptr_t));
 #ifndef NDEBUG
-    if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+    if (grpc_trace_error_refcount.enabled()) {
       gpr_log(GPR_DEBUG, "%p create copying %p", out, in);
     }
 #endif

src/core/lib/iomgr/error.h

@@ -39,7 +39,7 @@ extern "C" {
 typedef struct grpc_error grpc_error;
 
 #ifndef NDEBUG
-extern grpc_tracer_flag grpc_trace_error_refcount;
+extern grpc_core::TraceFlag grpc_trace_error_refcount;
 #endif
 
 typedef enum {

src/core/lib/iomgr/ev_epoll1_linux.cc

@@ -274,7 +274,7 @@ static grpc_fd *fd_create(int fd, const char *name) {
   gpr_asprintf(&fd_name, "%s fd=%d", name, fd);
   grpc_iomgr_register_object(&new_fd->iomgr_object, fd_name);
 #ifndef NDEBUG
-  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+  if (grpc_trace_fd_refcount.enabled()) {
     gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, new_fd, fd_name);
   }
 #endif
@@ -650,7 +650,7 @@ static grpc_error *do_epoll_wait(grpc_exec_ctx *exec_ctx, grpc_pollset *ps,
 
   GRPC_STATS_INC_POLL_EVENTS_RETURNED(exec_ctx, r);
 
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "ps: %p poll got %d events", ps, r);
   }
 
@@ -672,7 +672,7 @@ static bool begin_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   worker->schedule_on_end_work = (grpc_closure_list)GRPC_CLOSURE_LIST_INIT;
   pollset->begin_refs++;
 
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_ERROR, "PS:%p BEGIN_STARTS:%p", pollset, worker);
   }
 
@@ -691,7 +691,7 @@ static bool begin_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   retry_lock_neighborhood:
     gpr_mu_lock(&neighborhood->mu);
     gpr_mu_lock(&pollset->mu);
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_ERROR, "PS:%p BEGIN_REORG:%p kick_state=%s is_reassigning=%d",
               pollset, worker, kick_state_string(worker->state),
               is_reassigning);
@@ -743,7 +743,7 @@ static bool begin_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     worker->initialized_cv = true;
     gpr_cv_init(&worker->cv);
     while (worker->state == UNKICKED && !pollset->shutting_down) {
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+      if (grpc_polling_trace.enabled()) {
         gpr_log(GPR_ERROR, "PS:%p BEGIN_WAIT:%p kick_state=%s shutdown=%d",
                 pollset, worker, kick_state_string(worker->state),
                 pollset->shutting_down);
@@ -760,7 +760,7 @@ static bool begin_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     grpc_exec_ctx_invalidate_now(exec_ctx);
   }
 
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_ERROR,
             "PS:%p BEGIN_DONE:%p kick_state=%s shutdown=%d "
             "kicked_without_poller: %d",
@@ -805,7 +805,7 @@ static bool check_neighborhood_for_available_poller(
           case UNKICKED:
             if (gpr_atm_no_barrier_cas(&g_active_poller, 0,
                                        (gpr_atm)inspect_worker)) {
-              if (GRPC_TRACER_ON(grpc_polling_trace)) {
+              if (grpc_polling_trace.enabled()) {
                 gpr_log(GPR_DEBUG, " .. choose next poller to be %p",
                         inspect_worker);
               }
@@ -816,7 +816,7 @@ static bool check_neighborhood_for_available_poller(
                 gpr_cv_signal(&inspect_worker->cv);
               }
             } else {
-              if (GRPC_TRACER_ON(grpc_polling_trace)) {
+              if (grpc_polling_trace.enabled()) {
                 gpr_log(GPR_DEBUG, " .. beaten to choose next poller");
               }
             }
@@ -834,7 +834,7 @@ static bool check_neighborhood_for_available_poller(
       } while (!found_worker && inspect_worker != inspect->root_worker);
     }
     if (!found_worker) {
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+      if (grpc_polling_trace.enabled()) {
         gpr_log(GPR_DEBUG, " .. mark pollset %p inactive", inspect);
       }
       inspect->seen_inactive = true;
@@ -856,7 +856,7 @@ static void end_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                        grpc_pollset_worker *worker,
                        grpc_pollset_worker **worker_hdl) {
   GPR_TIMER_BEGIN("end_worker", 0);
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PS:%p END_WORKER:%p", pollset, worker);
   }
   if (worker_hdl != NULL) *worker_hdl = NULL;
@@ -866,7 +866,7 @@ static void end_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                          &exec_ctx->closure_list);
   if (gpr_atm_no_barrier_load(&g_active_poller) == (gpr_atm)worker) {
     if (worker->next != worker && worker->next->state == UNKICKED) {
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+      if (grpc_polling_trace.enabled()) {
         gpr_log(GPR_DEBUG, " .. choose next poller to be peer %p", worker);
       }
       GPR_ASSERT(worker->next->initialized_cv);
@@ -920,7 +920,7 @@ static void end_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   if (worker->initialized_cv) {
     gpr_cv_destroy(&worker->cv);
   }
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, " .. remove worker");
   }
   if (EMPTIED == worker_remove(pollset, worker)) {
@@ -992,7 +992,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   GPR_TIMER_BEGIN("pollset_kick", 0);
   GRPC_STATS_INC_POLLSET_KICK(exec_ctx);
   grpc_error *ret_err = GRPC_ERROR_NONE;
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_strvec log;
     gpr_strvec_init(&log);
     char *tmp;
@@ -1025,7 +1025,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
       if (root_worker == NULL) {
         GRPC_STATS_INC_POLLSET_KICKED_WITHOUT_POLLER(exec_ctx);
         pollset->kicked_without_poller = true;
-        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        if (grpc_polling_trace.enabled()) {
           gpr_log(GPR_ERROR, " .. kicked_without_poller");
         }
         goto done;
@@ -1033,14 +1033,14 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
       grpc_pollset_worker *next_worker = root_worker->next;
       if (root_worker->state == KICKED) {
         GRPC_STATS_INC_POLLSET_KICKED_AGAIN(exec_ctx);
-        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        if (grpc_polling_trace.enabled()) {
           gpr_log(GPR_ERROR, " .. already kicked %p", root_worker);
         }
         SET_KICK_STATE(root_worker, KICKED);
         goto done;
       } else if (next_worker->state == KICKED) {
         GRPC_STATS_INC_POLLSET_KICKED_AGAIN(exec_ctx);
-        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        if (grpc_polling_trace.enabled()) {
           gpr_log(GPR_ERROR, " .. already kicked %p", next_worker);
         }
         SET_KICK_STATE(next_worker, KICKED);
@@ -1051,7 +1051,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                  root_worker == (grpc_pollset_worker *)gpr_atm_no_barrier_load(
                                     &g_active_poller)) {
         GRPC_STATS_INC_POLLSET_KICK_WAKEUP_FD(exec_ctx);
-        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        if (grpc_polling_trace.enabled()) {
           gpr_log(GPR_ERROR, " .. kicked %p", root_worker);
         }
         SET_KICK_STATE(root_worker, KICKED);
@@ -1059,7 +1059,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
         goto done;
       } else if (next_worker->state == UNKICKED) {
         GRPC_STATS_INC_POLLSET_KICK_WAKEUP_CV(exec_ctx);
-        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        if (grpc_polling_trace.enabled()) {
           gpr_log(GPR_ERROR, " .. kicked %p", next_worker);
         }
         GPR_ASSERT(next_worker->initialized_cv);
@@ -1068,7 +1068,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
         goto done;
       } else if (next_worker->state == DESIGNATED_POLLER) {
         if (root_worker->state != DESIGNATED_POLLER) {
-          if (GRPC_TRACER_ON(grpc_polling_trace)) {
+          if (grpc_polling_trace.enabled()) {
             gpr_log(
                 GPR_ERROR,
                 " .. kicked root non-poller %p (initialized_cv=%d) (poller=%p)",
@@ -1082,7 +1082,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
           goto done;
         } else {
           GRPC_STATS_INC_POLLSET_KICK_WAKEUP_FD(exec_ctx);
-          if (GRPC_TRACER_ON(grpc_polling_trace)) {
+          if (grpc_polling_trace.enabled()) {
             gpr_log(GPR_ERROR, " .. non-root poller %p (root=%p)", next_worker,
                     root_worker);
           }
@@ -1098,7 +1098,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
       }
     } else {
       GRPC_STATS_INC_POLLSET_KICK_OWN_THREAD(exec_ctx);
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+      if (grpc_polling_trace.enabled()) {
         gpr_log(GPR_ERROR, " .. kicked while waking up");
       }
       goto done;
@@ -1108,14 +1108,14 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   }
 
   if (specific_worker->state == KICKED) {
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_ERROR, " .. specific worker already kicked");
     }
     goto done;
   } else if (gpr_tls_get(&g_current_thread_worker) ==
              (intptr_t)specific_worker) {
     GRPC_STATS_INC_POLLSET_KICK_OWN_THREAD(exec_ctx);
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_ERROR, " .. mark %p kicked", specific_worker);
     }
     SET_KICK_STATE(specific_worker, KICKED);
@@ -1123,7 +1123,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   } else if (specific_worker ==
              (grpc_pollset_worker *)gpr_atm_no_barrier_load(&g_active_poller)) {
     GRPC_STATS_INC_POLLSET_KICK_WAKEUP_FD(exec_ctx);
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_ERROR, " .. kick active poller");
     }
     SET_KICK_STATE(specific_worker, KICKED);
@@ -1131,7 +1131,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     goto done;
   } else if (specific_worker->initialized_cv) {
     GRPC_STATS_INC_POLLSET_KICK_WAKEUP_CV(exec_ctx);
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_ERROR, " .. kick waiting worker");
     }
     SET_KICK_STATE(specific_worker, KICKED);
@@ -1139,7 +1139,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     goto done;
   } else {
     GRPC_STATS_INC_POLLSET_KICKED_AGAIN(exec_ctx);
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_ERROR, " .. kick non-waiting worker");
     }
     SET_KICK_STATE(specific_worker, KICKED);

src/core/lib/iomgr/ev_epollex_linux.cc

@@ -57,10 +57,8 @@
 #define MAX_EPOLL_EVENTS 100
 #define MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL 5
 
-#ifndef NDEBUG
-grpc_tracer_flag grpc_trace_pollable_refcount =
-    GRPC_TRACER_INITIALIZER(false, "pollable_refcount");
-#endif
+grpc_core::DebugOnlyTraceFlag grpc_trace_pollable_refcount(false,
+                                                           "pollable_refcount");
 
 /*******************************************************************************
  * pollable Declarations
@@ -261,7 +259,7 @@ static gpr_mu fd_freelist_mu;
   unref_by(ec, fd, n, reason, __FILE__, __LINE__)
 static void ref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                    int line) {
-  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+  if (grpc_trace_fd_refcount.enabled()) {
     gpr_log(GPR_DEBUG,
             "FD %d %p   ref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
             fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
@@ -295,7 +293,7 @@ static void fd_destroy(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
 #ifndef NDEBUG
 static void unref_by(grpc_exec_ctx *exec_ctx, grpc_fd *fd, int n,
                      const char *reason, const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+  if (grpc_trace_fd_refcount.enabled()) {
     gpr_log(GPR_DEBUG,
             "FD %d %p unref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
             fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
@@ -357,7 +355,7 @@ static grpc_fd *fd_create(int fd, const char *name) {
   gpr_asprintf(&fd_name, "%s fd=%d", name, fd);
   grpc_iomgr_register_object(&new_fd->iomgr_object, fd_name);
 #ifndef NDEBUG
-  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+  if (grpc_trace_fd_refcount.enabled()) {
     gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, new_fd, fd_name);
   }
 #endif
@@ -481,7 +479,7 @@ static grpc_error *pollable_create(pollable_type type, pollable **p) {
 static pollable *pollable_ref(pollable *p) {
 #else
 static pollable *pollable_ref(pollable *p, int line, const char *reason) {
-  if (GRPC_TRACER_ON(grpc_trace_pollable_refcount)) {
+  if (grpc_trace_pollable_refcount.enabled()) {
     int r = (int)gpr_atm_no_barrier_load(&p->refs.count);
     gpr_log(__FILE__, line, GPR_LOG_SEVERITY_DEBUG,
             "POLLABLE:%p   ref %d->%d %s", p, r, r + 1, reason);
@@ -496,7 +494,7 @@ static void pollable_unref(pollable *p) {
 #else
 static void pollable_unref(pollable *p, int line, const char *reason) {
   if (p == NULL) return;
-  if (GRPC_TRACER_ON(grpc_trace_pollable_refcount)) {
+  if (grpc_trace_pollable_refcount.enabled()) {
     int r = (int)gpr_atm_no_barrier_load(&p->refs.count);
     gpr_log(__FILE__, line, GPR_LOG_SEVERITY_DEBUG,
             "POLLABLE:%p unref %d->%d %s", p, r, r - 1, reason);
@@ -514,7 +512,7 @@ static grpc_error *pollable_add_fd(pollable *p, grpc_fd *fd) {
   static const char *err_desc = "pollable_add_fd";
   const int epfd = p->epfd;
 
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "add fd %p (%d) to pollable %p", fd, fd->fd, p);
   }
 
@@ -556,7 +554,7 @@ static void pollset_global_shutdown(void) {
 /* pollset->mu must be held while calling this function */
 static void pollset_maybe_finish_shutdown(grpc_exec_ctx *exec_ctx,
                                           grpc_pollset *pollset) {
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "PS:%p (pollable:%p) maybe_finish_shutdown sc=%p (target:!NULL) "
             "rw=%p (target:NULL) cpsc=%d (target:0)",
@@ -580,14 +578,14 @@ static grpc_error *kick_one_worker(grpc_exec_ctx *exec_ctx,
   GRPC_STATS_INC_POLLSET_KICK(exec_ctx);
   GPR_ASSERT(specific_worker != NULL);
   if (specific_worker->kicked) {
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_DEBUG, "PS:%p kicked_specific_but_already_kicked", p);
     }
     GRPC_STATS_INC_POLLSET_KICKED_AGAIN(exec_ctx);
     return GRPC_ERROR_NONE;
   }
   if (gpr_tls_get(&g_current_thread_worker) == (intptr_t)specific_worker) {
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_DEBUG, "PS:%p kicked_specific_but_awake", p);
     }
     GRPC_STATS_INC_POLLSET_KICK_OWN_THREAD(exec_ctx);
@@ -596,7 +594,7 @@ static grpc_error *kick_one_worker(grpc_exec_ctx *exec_ctx,
   }
   if (specific_worker == p->root_worker) {
     GRPC_STATS_INC_POLLSET_KICK_WAKEUP_FD(exec_ctx);
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_DEBUG, "PS:%p kicked_specific_via_wakeup_fd", p);
     }
     specific_worker->kicked = true;
@@ -605,7 +603,7 @@ static grpc_error *kick_one_worker(grpc_exec_ctx *exec_ctx,
   }
   if (specific_worker->initialized_cv) {
     GRPC_STATS_INC_POLLSET_KICK_WAKEUP_CV(exec_ctx);
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_DEBUG, "PS:%p kicked_specific_via_cv", p);
     }
     specific_worker->kicked = true;
@@ -619,7 +617,7 @@ static grpc_error *kick_one_worker(grpc_exec_ctx *exec_ctx,
 
 static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                                 grpc_pollset_worker *specific_worker) {
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "PS:%p kick %p tls_pollset=%p tls_worker=%p pollset.root_worker=%p",
             pollset, specific_worker,
@@ -630,7 +628,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   if (specific_worker == NULL) {
     if (gpr_tls_get(&g_current_thread_pollset) != (intptr_t)pollset) {
       if (pollset->root_worker == NULL) {
-        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        if (grpc_polling_trace.enabled()) {
           gpr_log(GPR_DEBUG, "PS:%p kicked_any_without_poller", pollset);
         }
         GRPC_STATS_INC_POLLSET_KICKED_WITHOUT_POLLER(exec_ctx);
@@ -656,7 +654,7 @@ static grpc_error *pollset_kick(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
             exec_ctx, pollset->root_worker->links[PWLINK_POLLSET].next);
       }
     } else {
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+      if (grpc_polling_trace.enabled()) {
         gpr_log(GPR_DEBUG, "PS:%p kicked_any_but_awake", pollset);
       }
       GRPC_STATS_INC_POLLSET_KICK_OWN_THREAD(exec_ctx);
@@ -763,7 +761,7 @@ static grpc_error *pollable_process_events(grpc_exec_ctx *exec_ctx,
     struct epoll_event *ev = &pollable_obj->events[n];
     void *data_ptr = ev->data.ptr;
     if (1 & (intptr_t)data_ptr) {
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+      if (grpc_polling_trace.enabled()) {
         gpr_log(GPR_DEBUG, "PS:%p got pollset_wakeup %p", pollset, data_ptr);
       }
       append_error(&error,
@@ -775,7 +773,7 @@ static grpc_error *pollable_process_events(grpc_exec_ctx *exec_ctx,
       bool cancel = (ev->events & (EPOLLERR | EPOLLHUP)) != 0;
       bool read_ev = (ev->events & (EPOLLIN | EPOLLPRI)) != 0;
       bool write_ev = (ev->events & EPOLLOUT) != 0;
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+      if (grpc_polling_trace.enabled()) {
         gpr_log(GPR_DEBUG,
                 "PS:%p got fd %p: cancel=%d read=%d "
                 "write=%d",
@@ -803,7 +801,7 @@ static grpc_error *pollable_epoll(grpc_exec_ctx *exec_ctx, pollable *p,
                                   grpc_millis deadline) {
   int timeout = poll_deadline_to_millis_timeout(exec_ctx, deadline);
 
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     char *desc = pollable_desc(p);
     gpr_log(GPR_DEBUG, "POLLABLE:%p[%s] poll for %dms", p, desc, timeout);
     gpr_free(desc);
@@ -823,7 +821,7 @@ static grpc_error *pollable_epoll(grpc_exec_ctx *exec_ctx, pollable *p,
 
   if (r < 0) return GRPC_OS_ERROR(errno, "epoll_wait");
 
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "POLLABLE:%p got %d events", p, r);
   }
 
@@ -891,7 +889,7 @@ static bool begin_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     worker->initialized_cv = true;
     gpr_cv_init(&worker->cv);
     gpr_mu_unlock(&pollset->mu);
-    if (GRPC_TRACER_ON(grpc_polling_trace) &&
+    if (grpc_polling_trace.enabled() &&
         worker->pollable_obj->root_worker != worker) {
       gpr_log(GPR_DEBUG, "PS:%p wait %p w=%p for %dms", pollset,
               worker->pollable_obj, worker,
@@ -900,18 +898,18 @@ static bool begin_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     while (do_poll && worker->pollable_obj->root_worker != worker) {
       if (gpr_cv_wait(&worker->cv, &worker->pollable_obj->mu,
                       grpc_millis_to_timespec(deadline, GPR_CLOCK_REALTIME))) {
-        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        if (grpc_polling_trace.enabled()) {
           gpr_log(GPR_DEBUG, "PS:%p timeout_wait %p w=%p", pollset,
                   worker->pollable_obj, worker);
         }
         do_poll = false;
       } else if (worker->kicked) {
-        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        if (grpc_polling_trace.enabled()) {
           gpr_log(GPR_DEBUG, "PS:%p wakeup %p w=%p", pollset,
                   worker->pollable_obj, worker);
         }
         do_poll = false;
-      } else if (GRPC_TRACER_ON(grpc_polling_trace) &&
+      } else if (grpc_polling_trace.enabled() &&
                  worker->pollable_obj->root_worker != worker) {
         gpr_log(GPR_DEBUG, "PS:%p spurious_wakeup %p w=%p", pollset,
                 worker->pollable_obj, worker);
@@ -982,7 +980,7 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
 #ifndef NDEBUG
   WORKER_PTR->originator = gettid();
 #endif
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PS:%p work hdl=%p worker=%p now=%" PRIdPTR
                        " deadline=%" PRIdPTR " kwp=%d pollable=%p",
             pollset, worker_hdl, WORKER_PTR, grpc_exec_ctx_now(exec_ctx),
@@ -1023,7 +1021,7 @@ static grpc_error *pollset_transition_pollable_from_empty_to_fd_locked(
     grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, grpc_fd *fd) {
   static const char *err_desc = "pollset_transition_pollable_from_empty_to_fd";
   grpc_error *error = GRPC_ERROR_NONE;
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "PS:%p add fd %p (%d); transition pollable from empty to fd",
             pollset, fd, fd->fd);
@@ -1039,7 +1037,7 @@ static grpc_error *pollset_transition_pollable_from_fd_to_multi_locked(
     grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, grpc_fd *and_add_fd) {
   static const char *err_desc = "pollset_transition_pollable_from_fd_to_multi";
   grpc_error *error = GRPC_ERROR_NONE;
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(
         GPR_DEBUG,
         "PS:%p add fd %p (%d); transition pollable from fd %p to multipoller",
@@ -1189,7 +1187,7 @@ static void pollset_set_unref(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss) {
 
 static void pollset_set_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss,
                                grpc_fd *fd) {
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS:%p: add fd %p (%d)", pss, fd, fd->fd);
   }
   grpc_error *error = GRPC_ERROR_NONE;
@@ -1213,7 +1211,7 @@ static void pollset_set_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss,
 
 static void pollset_set_del_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss,
                                grpc_fd *fd) {
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS:%p: del fd %p", pss, fd);
   }
   pss = pss_lock_adam(pss);
@@ -1234,7 +1232,7 @@ static void pollset_set_del_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss,
 
 static void pollset_set_del_pollset(grpc_exec_ctx *exec_ctx,
                                     grpc_pollset_set *pss, grpc_pollset *ps) {
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS:%p: del pollset %p", pss, ps);
   }
   pss = pss_lock_adam(pss);
@@ -1285,7 +1283,7 @@ static grpc_error *add_fds_to_pollsets(grpc_exec_ctx *exec_ctx, grpc_fd **fds,
 
 static void pollset_set_add_pollset(grpc_exec_ctx *exec_ctx,
                                     grpc_pollset_set *pss, grpc_pollset *ps) {
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS:%p: add pollset %p", pss, ps);
   }
   grpc_error *error = GRPC_ERROR_NONE;
@@ -1322,7 +1320,7 @@ static void pollset_set_add_pollset(grpc_exec_ctx *exec_ctx,
 static void pollset_set_add_pollset_set(grpc_exec_ctx *exec_ctx,
                                         grpc_pollset_set *a,
                                         grpc_pollset_set *b) {
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS: merge (%p, %p)", a, b);
   }
   grpc_error *error = GRPC_ERROR_NONE;
@@ -1356,7 +1354,7 @@ static void pollset_set_add_pollset_set(grpc_exec_ctx *exec_ctx,
   if (b_size > a_size) {
     GPR_SWAP(grpc_pollset_set *, a, b);
   }
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS: parent %p to %p", b, a);
   }
   gpr_ref(&a->refs);
@@ -1453,10 +1451,6 @@ const grpc_event_engine_vtable *grpc_init_epollex_linux(
     return NULL;
   }
 
-#ifndef NDEBUG
-  grpc_register_tracer(&grpc_trace_pollable_refcount);
-#endif
-
   fd_global_init();
 
   if (!GRPC_LOG_IF_ERROR("pollset_global_init", pollset_global_init())) {

src/core/lib/iomgr/ev_epollsig_linux.cc

@@ -54,7 +54,7 @@
 #define GRPC_POLLSET_KICK_BROADCAST ((grpc_pollset_worker *)1)
 
 #define GRPC_POLLING_TRACE(...)       \
-  if (GRPC_TRACER_ON(grpc_polling_trace)) { \
+  if (grpc_polling_trace.enabled()) { \
     gpr_log(GPR_INFO, __VA_ARGS__);   \
   }
 
@@ -288,7 +288,7 @@ static void pi_unref(grpc_exec_ctx *exec_ctx, polling_island *pi);
 #ifndef NDEBUG
 static void pi_add_ref_dbg(polling_island *pi, const char *reason,
                            const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count);
     gpr_log(GPR_DEBUG, "Add ref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR
                        " (%s) - (%s, %d)",
@@ -299,7 +299,7 @@ static void pi_add_ref_dbg(polling_island *pi, const char *reason,
 
 static void pi_unref_dbg(grpc_exec_ctx *exec_ctx, polling_island *pi,
                          const char *reason, const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+  if (grpc_polling_trace.enabled()) {
     gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count);
     gpr_log(GPR_DEBUG, "Unref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR
                        " (%s) - (%s, %d)",
@@ -730,7 +730,7 @@ static gpr_mu fd_freelist_mu;
 #define UNREF_BY(fd, n, reason) unref_by(fd, n, reason, __FILE__, __LINE__)
 static void ref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                    int line) {
-  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+  if (grpc_trace_fd_refcount.enabled()) {
     gpr_log(GPR_DEBUG,
             "FD %d %p   ref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
             fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
@@ -747,7 +747,7 @@ static void ref_by(grpc_fd *fd, int n) {
 #ifndef NDEBUG
 static void unref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                      int line) {
-  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+  if (grpc_trace_fd_refcount.enabled()) {
     gpr_log(GPR_DEBUG,
             "FD %d %p unref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
             fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),

src/core/lib/iomgr/ev_poll_posix.cc

@@ -288,7 +288,7 @@ cv_fd_table g_cvfds;
 #define UNREF_BY(fd, n, reason) unref_by(fd, n, reason, __FILE__, __LINE__)
 static void ref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                    int line) {
-  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+  if (grpc_trace_fd_refcount.enabled()) {
     gpr_log(GPR_DEBUG,
             "FD %d %p   ref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
             fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
@@ -305,7 +305,7 @@ static void ref_by(grpc_fd *fd, int n) {
 #ifndef NDEBUG
 static void unref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                      int line) {
-  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+  if (grpc_trace_fd_refcount.enabled()) {
     gpr_log(GPR_DEBUG,
             "FD %d %p unref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
             fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
@@ -992,7 +992,7 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
       r = grpc_poll_function(pfds, pfd_count, timeout);
       GRPC_SCHEDULING_END_BLOCKING_REGION_WITH_EXEC_CTX(exec_ctx);
 
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+      if (grpc_polling_trace.enabled()) {
         gpr_log(GPR_DEBUG, "%p poll=%d", pollset, r);
       }
 
@@ -1016,7 +1016,7 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
         }
       } else {
         if (pfds[0].revents & POLLIN_CHECK) {
-          if (GRPC_TRACER_ON(grpc_polling_trace)) {
+          if (grpc_polling_trace.enabled()) {
             gpr_log(GPR_DEBUG, "%p: got_wakeup", pollset);
           }
           work_combine_error(
@@ -1026,7 +1026,7 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
           if (watchers[i].fd == NULL) {
             fd_end_poll(exec_ctx, &watchers[i], 0, 0, NULL);
           } else {
-            if (GRPC_TRACER_ON(grpc_polling_trace)) {
+            if (grpc_polling_trace.enabled()) {
               gpr_log(GPR_DEBUG, "%p got_event: %d r:%d w:%d [%d]", pollset,
                       pfds[i].fd, (pfds[i].revents & POLLIN_CHECK) != 0,
                       (pfds[i].revents & POLLOUT_CHECK) != 0, pfds[i].revents);

src/core/lib/iomgr/ev_posix.cc

@@ -36,12 +36,11 @@
 #include "src/core/lib/iomgr/ev_poll_posix.h"
 #include "src/core/lib/support/env.h"
 
-grpc_tracer_flag grpc_polling_trace =
-    GRPC_TRACER_INITIALIZER(false, "polling"); /* Disabled by default */
+grpc_core::TraceFlag grpc_polling_trace(false,
+                                     "polling"); /* Disabled by default */
 
 #ifndef NDEBUG
-grpc_tracer_flag grpc_trace_fd_refcount =
-    GRPC_TRACER_INITIALIZER(false, "fd_refcount");
+grpc_core::TraceFlag grpc_trace_fd_refcount(false, "fd_refcount");
 #endif
 
 /** Default poll() function - a pointer so that it can be overridden by some
@@ -153,8 +152,6 @@ const grpc_event_engine_vtable *grpc_get_event_engine_test_only() {
 const char *grpc_get_poll_strategy_name() { return g_poll_strategy_name; }
 
 void grpc_event_engine_init(void) {
-  grpc_register_tracer(&grpc_polling_trace);
-
   char *s = gpr_getenv("GRPC_POLL_STRATEGY");
   if (s == NULL) {
     s = gpr_strdup("all");

src/core/lib/iomgr/ev_posix.h

@@ -31,7 +31,7 @@
 extern "C" {
 #endif
 
-extern grpc_tracer_flag grpc_polling_trace; /* Disabled by default */
+extern grpc_core::TraceFlag grpc_polling_trace; /* Disabled by default */
 
 typedef struct grpc_fd grpc_fd;
 

src/core/lib/iomgr/ev_windows.cc

@@ -22,7 +22,7 @@
 
 #include "src/core/lib/debug/trace.h"
 
-grpc_tracer_flag grpc_polling_trace =
-    GRPC_TRACER_INITIALIZER(false, "polling"); /* Disabled by default */
+grpc_core::TraceFlag grpc_polling_trace(false,
+                                     "polling"); /* Disabled by default */
 
 #endif  // GRPC_WINSOCK_SOCKET

src/core/lib/iomgr/exec_ctx.cc

@@ -60,7 +60,7 @@ static void exec_ctx_run(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
                          grpc_error *error) {
 #ifndef NDEBUG
   closure->scheduled = false;
-  if (GRPC_TRACER_ON(grpc_trace_closure)) {
+  if (grpc_trace_closure.enabled()) {
     gpr_log(GPR_DEBUG, "running closure %p: created [%s:%d]: %s [%s:%d]",
             closure, closure->file_created, closure->line_created,
             closure->run ? "run" : "scheduled", closure->file_initiated,
@@ -69,7 +69,7 @@ static void exec_ctx_run(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
 #endif
   closure->cb(exec_ctx, closure->cb_arg, error);
 #ifndef NDEBUG
-  if (GRPC_TRACER_ON(grpc_trace_closure)) {
+  if (grpc_trace_closure.enabled()) {
     gpr_log(GPR_DEBUG, "closure %p finished", closure);
   }
 #endif

src/core/lib/iomgr/executor.cc

@@ -51,8 +51,7 @@ static gpr_spinlock g_adding_thread_lock = GPR_SPINLOCK_STATIC_INITIALIZER;
 
 GPR_TLS_DECL(g_this_thread_state);
 
-static grpc_tracer_flag executor_trace =
-    GRPC_TRACER_INITIALIZER(false, "executor");
+static grpc_core::TraceFlag executor_trace(false, "executor");
 
 static void executor_thread(void *arg);
 
@@ -63,7 +62,7 @@ static size_t run_closures(grpc_exec_ctx *exec_ctx, grpc_closure_list list) {
   while (c != NULL) {
     grpc_closure *next = c->next_data.next;
     grpc_error *error = c->error_data.error;
-    if (GRPC_TRACER_ON(executor_trace)) {
+    if (executor_trace.enabled()) {
 #ifndef NDEBUG
       gpr_log(GPR_DEBUG, "EXECUTOR: run %p [created by %s:%d]", c,
               c->file_created, c->line_created);
@@ -134,7 +133,6 @@ void grpc_executor_set_threading(grpc_exec_ctx *exec_ctx, bool threading) {
 }
 
 void grpc_executor_init(grpc_exec_ctx *exec_ctx) {
-  grpc_register_tracer(&executor_trace);
   gpr_atm_no_barrier_store(&g_cur_threads, 0);
   grpc_executor_set_threading(exec_ctx, true);
 }
@@ -152,7 +150,7 @@ static void executor_thread(void *arg) {
 
   size_t subtract_depth = 0;
   for (;;) {
-    if (GRPC_TRACER_ON(executor_trace)) {
+    if (executor_trace.enabled()) {
       gpr_log(GPR_DEBUG, "EXECUTOR[%d]: step (sub_depth=%" PRIdPTR ")",
               (int)(ts - g_thread_state), subtract_depth);
     }
@@ -163,7 +161,7 @@ static void executor_thread(void *arg) {
       gpr_cv_wait(&ts->cv, &ts->mu, gpr_inf_future(GPR_CLOCK_REALTIME));
     }
     if (ts->shutdown) {
-      if (GRPC_TRACER_ON(executor_trace)) {
+      if (executor_trace.enabled()) {
         gpr_log(GPR_DEBUG, "EXECUTOR[%d]: shutdown",
                 (int)(ts - g_thread_state));
       }
@@ -174,7 +172,7 @@ static void executor_thread(void *arg) {
     grpc_closure_list exec = ts->elems;
     ts->elems = GRPC_CLOSURE_LIST_INIT;
     gpr_mu_unlock(&ts->mu);
-    if (GRPC_TRACER_ON(executor_trace)) {
+    if (executor_trace.enabled()) {
       gpr_log(GPR_DEBUG, "EXECUTOR[%d]: execute", (int)(ts - g_thread_state));
     }
 
@@ -196,7 +194,7 @@ static void executor_push(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
     retry_push = false;
     size_t cur_thread_count = (size_t)gpr_atm_no_barrier_load(&g_cur_threads);
     if (cur_thread_count == 0) {
-      if (GRPC_TRACER_ON(executor_trace)) {
+      if (executor_trace.enabled()) {
 #ifndef NDEBUG
         gpr_log(GPR_DEBUG, "EXECUTOR: schedule %p (created %s:%d) inline",
                 closure, closure->file_created, closure->line_created);
@@ -217,7 +215,7 @@ static void executor_push(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
 
     bool try_new_thread;
     for (;;) {
-      if (GRPC_TRACER_ON(executor_trace)) {
+      if (executor_trace.enabled()) {
 #ifndef NDEBUG
         gpr_log(
             GPR_DEBUG,

src/core/lib/iomgr/iomgr_posix.cc

@@ -28,7 +28,6 @@
 void grpc_iomgr_platform_init(void) {
   grpc_wakeup_fd_global_init();
   grpc_event_engine_init();
-  grpc_register_tracer(&grpc_tcp_trace);
 }
 
 void grpc_iomgr_platform_flush(void) {}

src/core/lib/iomgr/iomgr_uv.cc

@@ -31,7 +31,7 @@ gpr_thd_id g_init_thread;
 void grpc_iomgr_platform_init(void) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_pollset_global_init();
-  grpc_register_tracer(&grpc_tcp_trace);
+
   grpc_executor_set_threading(&exec_ctx, false);
   g_init_thread = gpr_thd_currentid();
   grpc_exec_ctx_finish(&exec_ctx);

src/core/lib/iomgr/lockfree_event.cc

@@ -22,7 +22,7 @@
 
 #include "src/core/lib/debug/trace.h"
 
-extern grpc_tracer_flag grpc_polling_trace;
+extern grpc_core::TraceFlag grpc_polling_trace;
 
 /* 'state' holds the to call when the fd is readable or writable respectively.
    It can contain one of the following values:
@@ -82,7 +82,7 @@ void grpc_lfev_notify_on(grpc_exec_ctx *exec_ctx, gpr_atm *state,
                          grpc_closure *closure, const char *variable) {
   while (true) {
     gpr_atm curr = gpr_atm_no_barrier_load(state);
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_ERROR, "lfev_notify_on[%s]: %p curr=%p closure=%p", variable,
               state, (void *)curr, closure);
     }
@@ -148,7 +148,7 @@ bool grpc_lfev_set_shutdown(grpc_exec_ctx *exec_ctx, gpr_atm *state,
 
   while (true) {
     gpr_atm curr = gpr_atm_no_barrier_load(state);
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_ERROR, "lfev_set_shutdown: %p curr=%p err=%s", state,
               (void *)curr, grpc_error_string(shutdown_err));
     }
@@ -198,7 +198,7 @@ void grpc_lfev_set_ready(grpc_exec_ctx *exec_ctx, gpr_atm *state,
   while (true) {
     gpr_atm curr = gpr_atm_no_barrier_load(state);
 
-    if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    if (grpc_polling_trace.enabled()) {
       gpr_log(GPR_ERROR, "lfev_set_ready[%s]: %p curr=%p", variable, state,
               (void *)curr);
     }

src/core/lib/iomgr/pollset.h

@@ -30,7 +30,7 @@ extern "C" {
 #endif
 
 #ifndef NDEBUG
-extern grpc_tracer_flag grpc_trace_fd_refcount;
+extern grpc_core::TraceFlag grpc_trace_fd_refcount;
 #endif
 
 /* A grpc_pollset is a set of file descriptors that a higher level item is

src/core/lib/iomgr/pollset_uv.cc

@@ -34,10 +34,7 @@
 
 #include "src/core/lib/debug/trace.h"
 
-#ifndef NDEBUG
-grpc_tracer_flag grpc_trace_fd_refcount =
-    GRPC_TRACER_INITIALIZER(false, "fd_refcount");
-#endif
+grpc_core::DebugOnlyTraceFlag grpc_trace_fd_refcount(false, "fd_refcount");
 
 struct grpc_pollset {
   uv_timer_t timer;

src/core/lib/iomgr/pollset_windows.cc

@@ -30,10 +30,7 @@
 
 #define GRPC_POLLSET_KICK_BROADCAST ((grpc_pollset_worker *)1)
 
-#ifndef NDEBUG
-grpc_tracer_flag grpc_trace_fd_refcount =
-    GRPC_TRACER_INITIALIZER(false, "fd_refcount");
-#endif
+grpc_core::DebugOnlyTraceFlag grpc_trace_fd_refcount(false, "fd_refcount");
 
 gpr_mu grpc_polling_mu;
 static grpc_pollset_worker *g_active_poller;

src/core/lib/iomgr/resource_quota.cc

@@ -31,8 +31,7 @@
 
 #include "src/core/lib/iomgr/combiner.h"
 
-grpc_tracer_flag grpc_resource_quota_trace =
-    GRPC_TRACER_INITIALIZER(false, "resource_quota");
+grpc_core::TraceFlag grpc_resource_quota_trace(false, "resource_quota");
 
 #define MEMORY_USAGE_ESTIMATION_MAX 65536
 
@@ -294,7 +293,7 @@ static bool rq_alloc(grpc_exec_ctx *exec_ctx,
   while ((resource_user = rulist_pop_head(resource_quota,
                                           GRPC_RULIST_AWAITING_ALLOCATION))) {
     gpr_mu_lock(&resource_user->mu);
-    if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+    if (grpc_resource_quota_trace.enabled()) {
       gpr_log(GPR_DEBUG, "RQ: check allocation for user %p shutdown=%" PRIdPTR
                          " free_pool=%" PRId64,
               resource_user, gpr_atm_no_barrier_load(&resource_user->shutdown),
@@ -319,13 +318,13 @@ static bool rq_alloc(grpc_exec_ctx *exec_ctx,
       resource_user->free_pool = 0;
       resource_quota->free_pool -= amt;
       rq_update_estimate(resource_quota);
-      if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+      if (grpc_resource_quota_trace.enabled()) {
         gpr_log(GPR_DEBUG, "RQ %s %s: grant alloc %" PRId64
                            " bytes; rq_free_pool -> %" PRId64,
                 resource_quota->name, resource_user->name, amt,
                 resource_quota->free_pool);
       }
-    } else if (GRPC_TRACER_ON(grpc_resource_quota_trace) &&
+    } else if (grpc_resource_quota_trace.enabled() &&
                resource_user->free_pool >= 0) {
       gpr_log(GPR_DEBUG, "RQ %s %s: discard already satisfied alloc request",
               resource_quota->name, resource_user->name);
@@ -356,7 +355,7 @@ static bool rq_reclaim_from_per_user_free_pool(
       resource_user->free_pool = 0;
       resource_quota->free_pool += amt;
       rq_update_estimate(resource_quota);
-      if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+      if (grpc_resource_quota_trace.enabled()) {
         gpr_log(GPR_DEBUG, "RQ %s %s: reclaim_from_per_user_free_pool %" PRId64
                            " bytes; rq_free_pool -> %" PRId64,
                 resource_quota->name, resource_user->name, amt,
@@ -379,7 +378,7 @@ static bool rq_reclaim(grpc_exec_ctx *exec_ctx,
                                  : GRPC_RULIST_RECLAIMER_BENIGN;
   grpc_resource_user *resource_user = rulist_pop_head(resource_quota, list);
   if (resource_user == NULL) return false;
-  if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+  if (grpc_resource_quota_trace.enabled()) {
     gpr_log(GPR_DEBUG, "RQ %s %s: initiate %s reclamation",
             resource_quota->name, resource_user->name,
             destructive ? "destructive" : "benign");
@@ -513,7 +512,7 @@ static void ru_post_destructive_reclaimer(grpc_exec_ctx *exec_ctx, void *ru,
 }
 
 static void ru_shutdown(grpc_exec_ctx *exec_ctx, void *ru, grpc_error *error) {
-  if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+  if (grpc_resource_quota_trace.enabled()) {
     gpr_log(GPR_DEBUG, "RU shutdown %p", ru);
   }
   grpc_resource_user *resource_user = (grpc_resource_user *)ru;
@@ -811,7 +810,7 @@ void grpc_resource_user_alloc(grpc_exec_ctx *exec_ctx,
   ru_ref_by(resource_user, (gpr_atm)size);
   resource_user->free_pool -= (int64_t)size;
   resource_user->outstanding_allocations += (int64_t)size;
-  if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+  if (grpc_resource_quota_trace.enabled()) {
     gpr_log(GPR_DEBUG, "RQ %s %s: alloc %" PRIdPTR "; free_pool -> %" PRId64,
             resource_user->resource_quota->name, resource_user->name, size,
             resource_user->free_pool);
@@ -836,7 +835,7 @@ void grpc_resource_user_free(grpc_exec_ctx *exec_ctx,
   gpr_mu_lock(&resource_user->mu);
   bool was_zero_or_negative = resource_user->free_pool <= 0;
   resource_user->free_pool += (int64_t)size;
-  if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+  if (grpc_resource_quota_trace.enabled()) {
     gpr_log(GPR_DEBUG, "RQ %s %s: free %" PRIdPTR "; free_pool -> %" PRId64,
             resource_user->resource_quota->name, resource_user->name, size,
             resource_user->free_pool);
@@ -865,7 +864,7 @@ void grpc_resource_user_post_reclaimer(grpc_exec_ctx *exec_ctx,
 
 void grpc_resource_user_finish_reclamation(grpc_exec_ctx *exec_ctx,
                                            grpc_resource_user *resource_user) {
-  if (GRPC_TRACER_ON(grpc_resource_quota_trace)) {
+  if (grpc_resource_quota_trace.enabled()) {
     gpr_log(GPR_DEBUG, "RQ %s %s: reclamation complete",
             resource_user->resource_quota->name, resource_user->name);
   }

src/core/lib/iomgr/resource_quota.h

@@ -65,7 +65,7 @@ extern "C" {
     maintain lists of users (which users arrange to leave before they are
     destroyed) */
 
-extern grpc_tracer_flag grpc_resource_quota_trace;
+extern grpc_core::TraceFlag grpc_resource_quota_trace;
 
 grpc_resource_quota *grpc_resource_quota_ref_internal(
     grpc_resource_quota *resource_quota);

src/core/lib/iomgr/tcp_client_posix.cc

@@ -43,7 +43,7 @@
 #include "src/core/lib/iomgr/unix_sockets_posix.h"
 #include "src/core/lib/support/string.h"
 
-extern grpc_tracer_flag grpc_tcp_trace;
+extern grpc_core::TraceFlag grpc_tcp_trace;
 
 typedef struct {
   gpr_mu mu;
@@ -99,7 +99,7 @@ done:
 static void tc_on_alarm(grpc_exec_ctx *exec_ctx, void *acp, grpc_error *error) {
   int done;
   async_connect *ac = (async_connect *)acp;
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     const char *str = grpc_error_string(error);
     gpr_log(GPR_DEBUG, "CLIENT_CONNECT: %s: on_alarm: error=%s", ac->addr_str,
             str);
@@ -137,7 +137,7 @@ static void on_writable(grpc_exec_ctx *exec_ctx, void *acp, grpc_error *error) {
 
   GRPC_ERROR_REF(error);
 
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     const char *str = grpc_error_string(error);
     gpr_log(GPR_DEBUG, "CLIENT_CONNECT: %s: on_writable: error=%s",
             ac->addr_str, str);
@@ -317,7 +317,7 @@ static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
                     grpc_schedule_on_exec_ctx);
   ac->channel_args = grpc_channel_args_copy(channel_args);
 
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "CLIENT_CONNECT: %s: asynchronously connecting fd %p",
             ac->addr_str, fdobj);
   }

src/core/lib/iomgr/tcp_client_uv.cc

@@ -32,7 +32,7 @@
 #include "src/core/lib/iomgr/tcp_uv.h"
 #include "src/core/lib/iomgr/timer.h"
 
-extern grpc_tracer_flag grpc_tcp_trace;
+extern grpc_core::TraceFlag grpc_tcp_trace;
 
 typedef struct grpc_uv_tcp_connect {
   uv_connect_t connect_req;
@@ -59,7 +59,7 @@ static void uv_tc_on_alarm(grpc_exec_ctx *exec_ctx, void *acp,
                            grpc_error *error) {
   int done;
   grpc_uv_tcp_connect *connect = (grpc_uv_tcp_connect *)acp;
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     const char *str = grpc_error_string(error);
     gpr_log(GPR_DEBUG, "CLIENT_CONNECT: %s: on_alarm: error=%s",
             connect->addr_name, str);
@@ -147,7 +147,7 @@ static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
   connect->connect_req.data = connect;
   connect->refs = 2;  // One for the connect operation, one for the timer.
 
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "CLIENT_CONNECT: %s: asynchronously connecting",
             connect->addr_name);
   }

src/core/lib/iomgr/tcp_posix.cc

@@ -61,7 +61,7 @@ typedef GRPC_MSG_IOVLEN_TYPE msg_iovlen_type;
 typedef size_t msg_iovlen_type;
 #endif
 
-grpc_tracer_flag grpc_tcp_trace = GRPC_TRACER_INITIALIZER(false, "tcp");
+grpc_core::TraceFlag grpc_tcp_trace(false, "tcp");
 
 typedef struct {
   grpc_endpoint base;
@@ -121,7 +121,7 @@ static void tcp_drop_uncovered_then_handle_write(grpc_exec_ctx *exec_ctx,
 static void done_poller(grpc_exec_ctx *exec_ctx, void *bp,
                         grpc_error *error_ignored) {
   backup_poller *p = (backup_poller *)bp;
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "BACKUP_POLLER:%p destroy", p);
   }
   grpc_pollset_destroy(exec_ctx, BACKUP_POLLER_POLLSET(p));
@@ -131,7 +131,7 @@ static void done_poller(grpc_exec_ctx *exec_ctx, void *bp,
 static void run_poller(grpc_exec_ctx *exec_ctx, void *bp,
                        grpc_error *error_ignored) {
   backup_poller *p = (backup_poller *)bp;
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "BACKUP_POLLER:%p run", p);
   }
   gpr_mu_lock(p->pollset_mu);
@@ -147,18 +147,18 @@ static void run_poller(grpc_exec_ctx *exec_ctx, void *bp,
       gpr_atm_full_cas(&g_uncovered_notifications_pending, 1, 0)) {
     gpr_mu_lock(p->pollset_mu);
     bool cas_ok = gpr_atm_full_cas(&g_backup_poller, (gpr_atm)p, 0);
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       gpr_log(GPR_DEBUG, "BACKUP_POLLER:%p done cas_ok=%d", p, cas_ok);
     }
     gpr_mu_unlock(p->pollset_mu);
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       gpr_log(GPR_DEBUG, "BACKUP_POLLER:%p shutdown", p);
     }
     grpc_pollset_shutdown(exec_ctx, BACKUP_POLLER_POLLSET(p),
                           GRPC_CLOSURE_INIT(&p->run_poller, done_poller, p,
                                             grpc_schedule_on_exec_ctx));
   } else {
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       gpr_log(GPR_DEBUG, "BACKUP_POLLER:%p reschedule", p);
     }
     GRPC_CLOSURE_SCHED(exec_ctx, &p->run_poller, GRPC_ERROR_NONE);
@@ -169,7 +169,7 @@ static void drop_uncovered(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
   backup_poller *p = (backup_poller *)gpr_atm_acq_load(&g_backup_poller);
   gpr_atm old_count =
       gpr_atm_no_barrier_fetch_add(&g_uncovered_notifications_pending, -1);
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "BACKUP_POLLER:%p uncover cnt %d->%d", p, (int)old_count,
             (int)old_count - 1);
   }
@@ -180,14 +180,14 @@ static void cover_self(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
   backup_poller *p;
   gpr_atm old_count =
       gpr_atm_no_barrier_fetch_add(&g_uncovered_notifications_pending, 2);
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "BACKUP_POLLER: cover cnt %d->%d", (int)old_count,
             2 + (int)old_count);
   }
   if (old_count == 0) {
     GRPC_STATS_INC_TCP_BACKUP_POLLERS_CREATED(exec_ctx);
     p = (backup_poller *)gpr_zalloc(sizeof(*p) + grpc_pollset_size());
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       gpr_log(GPR_DEBUG, "BACKUP_POLLER:%p create", p);
     }
     grpc_pollset_init(BACKUP_POLLER_POLLSET(p), &p->pollset_mu);
@@ -202,7 +202,7 @@ static void cover_self(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
       // spin waiting for backup poller
     }
   }
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "BACKUP_POLLER:%p add %p", p, tcp);
   }
   grpc_pollset_add_fd(exec_ctx, BACKUP_POLLER_POLLSET(p), tcp->em_fd);
@@ -212,7 +212,7 @@ static void cover_self(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
 }
 
 static void notify_on_read(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "TCP:%p notify_on_read", tcp);
   }
   GRPC_CLOSURE_INIT(&tcp->read_done_closure, tcp_handle_read, tcp,
@@ -221,7 +221,7 @@ static void notify_on_read(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
 }
 
 static void notify_on_write(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "TCP:%p notify_on_write", tcp);
   }
   cover_self(exec_ctx, tcp);
@@ -233,7 +233,7 @@ static void notify_on_write(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
 
 static void tcp_drop_uncovered_then_handle_write(grpc_exec_ctx *exec_ctx,
                                                  void *arg, grpc_error *error) {
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "TCP:%p got_write: %s", arg, grpc_error_string(error));
   }
   drop_uncovered(exec_ctx, (grpc_tcp *)arg);
@@ -310,7 +310,7 @@ static void tcp_free(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
 #define TCP_REF(tcp, reason) tcp_ref((tcp), (reason), __FILE__, __LINE__)
 static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
                       const char *reason, const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "TCP unref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
@@ -323,7 +323,7 @@ static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
 
 static void tcp_ref(grpc_tcp *tcp, const char *reason, const char *file,
                     int line) {
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "TCP   ref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
@@ -354,7 +354,7 @@ static void call_read_cb(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
                          grpc_error *error) {
   grpc_closure *cb = tcp->read_cb;
 
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "TCP:%p call_cb %p %p:%p", tcp, cb, cb->cb, cb->cb_arg);
     size_t i;
     const char *str = grpc_error_string(error);
@@ -450,7 +450,7 @@ static void tcp_do_read(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
 static void tcp_read_allocation_done(grpc_exec_ctx *exec_ctx, void *tcpp,
                                      grpc_error *error) {
   grpc_tcp *tcp = (grpc_tcp *)tcpp;
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "TCP:%p read_allocation_done: %s", tcp,
             grpc_error_string(error));
   }
@@ -469,13 +469,13 @@ static void tcp_continue_read(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
   size_t target_read_size = get_target_read_size(tcp);
   if (tcp->incoming_buffer->length < target_read_size &&
       tcp->incoming_buffer->count < MAX_READ_IOVEC) {
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       gpr_log(GPR_DEBUG, "TCP:%p alloc_slices", tcp);
     }
     grpc_resource_user_alloc_slices(exec_ctx, &tcp->slice_allocator,
                                     target_read_size, 1, tcp->incoming_buffer);
   } else {
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       gpr_log(GPR_DEBUG, "TCP:%p do_read", tcp);
     }
     tcp_do_read(exec_ctx, tcp);
@@ -486,7 +486,7 @@ static void tcp_handle_read(grpc_exec_ctx *exec_ctx, void *arg /* grpc_tcp */,
                             grpc_error *error) {
   grpc_tcp *tcp = (grpc_tcp *)arg;
   GPR_ASSERT(!tcp->finished_edge);
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "TCP:%p got_read: %s", tcp, grpc_error_string(error));
   }
 
@@ -624,14 +624,14 @@ static void tcp_handle_write(grpc_exec_ctx *exec_ctx, void *arg /* grpc_tcp */,
   }
 
   if (!tcp_flush(exec_ctx, tcp, &error)) {
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       gpr_log(GPR_DEBUG, "write: delayed");
     }
     notify_on_write(exec_ctx, tcp);
   } else {
     cb = tcp->write_cb;
     tcp->write_cb = NULL;
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       const char *str = grpc_error_string(error);
       gpr_log(GPR_DEBUG, "write: %s", str);
     }
@@ -646,7 +646,7 @@ static void tcp_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   grpc_tcp *tcp = (grpc_tcp *)ep;
   grpc_error *error = GRPC_ERROR_NONE;
 
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     size_t i;
 
     for (i = 0; i < buf->count; i++) {
@@ -677,12 +677,12 @@ static void tcp_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   if (!tcp_flush(exec_ctx, tcp, &error)) {
     TCP_REF(tcp, "write");
     tcp->write_cb = cb;
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       gpr_log(GPR_DEBUG, "write: delayed");
     }
     notify_on_write(exec_ctx, tcp);
   } else {
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       const char *str = grpc_error_string(error);
       gpr_log(GPR_DEBUG, "write: %s", str);
     }

src/core/lib/iomgr/tcp_posix.h

@@ -37,7 +37,7 @@
 extern "C" {
 #endif
 
-extern grpc_tracer_flag grpc_tcp_trace;
+extern grpc_core::TraceFlag grpc_tcp_trace;
 
 /* Create a tcp endpoint given a file desciptor and a read slice size.
    Takes ownership of fd. */

src/core/lib/iomgr/tcp_server_posix.cc

@@ -242,7 +242,7 @@ static void on_read(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *err) {
     addr_str = grpc_sockaddr_to_uri(&addr);
     gpr_asprintf(&name, "tcp-server-connection:%s", addr_str);
 
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       gpr_log(GPR_DEBUG, "SERVER_CONNECT: incoming connection: %s", addr_str);
     }
 

src/core/lib/iomgr/tcp_server_uv.cc

@@ -213,7 +213,7 @@ static void finish_accept(grpc_exec_ctx *exec_ctx, grpc_tcp_listener *sp) {
   } else {
     gpr_log(GPR_INFO, "uv_tcp_getpeername error: %s", uv_strerror(err));
   }
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     if (peer_name_string) {
       gpr_log(GPR_DEBUG, "SERVER_CONNECT: %p accepted connection: %s",
               sp->server, peer_name_string);
@@ -247,7 +247,7 @@ static void on_connect(uv_stream_t *server, int status) {
 
   GPR_ASSERT(!sp->has_pending_connection);
 
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "SERVER_CONNECT: %p incoming connection", sp->server);
   }
 
@@ -403,7 +403,7 @@ grpc_error *grpc_tcp_server_add_port(grpc_tcp_server *s,
 
   gpr_free(allocated_addr);
 
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     char *port_string;
     grpc_sockaddr_to_string(&port_string, addr, 0);
     const char *str = grpc_error_string(error);
@@ -435,7 +435,7 @@ void grpc_tcp_server_start(grpc_exec_ctx *exec_ctx, grpc_tcp_server *server,
   (void)pollsets;
   (void)pollset_count;
   GRPC_UV_ASSERT_SAME_THREAD();
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "SERVER_START %p", server);
   }
   GPR_ASSERT(on_accept_cb);

src/core/lib/iomgr/tcp_uv.cc

@@ -38,7 +38,7 @@
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 
-grpc_tracer_flag grpc_tcp_trace = GRPC_TRACER_INITIALIZER(false, "tcp");
+grpc_core::TraceFlag grpc_tcp_trace(false, "tcp");
 
 typedef struct {
   grpc_endpoint base;
@@ -79,7 +79,7 @@ static void tcp_free(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
 #define TCP_REF(tcp, reason) tcp_ref((tcp), (reason), __FILE__, __LINE__)
 static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
                       const char *reason, const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "TCP unref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
@@ -92,7 +92,7 @@ static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
 
 static void tcp_ref(grpc_tcp *tcp, const char *reason, const char *file,
                     int line) {
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "TCP   ref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
@@ -158,7 +158,7 @@ static void read_callback(uv_stream_t *stream, ssize_t nread,
     grpc_slice_buffer_add(tcp->read_slices, sub);
     tcp->read_slice = alloc_read_slice(&exec_ctx, tcp->resource_user);
     error = GRPC_ERROR_NONE;
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       size_t i;
       const char *str = grpc_error_string(error);
       gpr_log(GPR_DEBUG, "read: error=%s", str);
@@ -200,7 +200,7 @@ static void uv_endpoint_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
                            grpc_slice_from_static_string(uv_strerror(status)));
     GRPC_CLOSURE_SCHED(exec_ctx, cb, error);
   }
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     const char *str = grpc_error_string(error);
     gpr_log(GPR_DEBUG, "Initiating read on %p: error=%s", tcp, str);
   }
@@ -218,7 +218,7 @@ static void write_callback(uv_write_t *req, int status) {
   } else {
     error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("TCP Write failed");
   }
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     const char *str = grpc_error_string(error);
     gpr_log(GPR_DEBUG, "write complete on %p: error=%s", tcp, str);
   }
@@ -240,7 +240,7 @@ static void uv_endpoint_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   uv_write_t *write_req;
   GRPC_UV_ASSERT_SAME_THREAD();
 
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     size_t j;
 
     for (j = 0; j < write_slices->count; j++) {
@@ -310,7 +310,7 @@ static void uv_endpoint_shutdown(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
                                  grpc_error *why) {
   grpc_tcp *tcp = (grpc_tcp *)ep;
   if (!tcp->shutting_down) {
-    if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    if (grpc_tcp_trace.enabled()) {
       const char *str = grpc_error_string(why);
       gpr_log(GPR_DEBUG, "TCP %p shutdown why=%s", tcp->handle, str);
     }
@@ -351,7 +351,7 @@ grpc_endpoint *grpc_tcp_create(uv_tcp_t *handle,
   grpc_tcp *tcp = (grpc_tcp *)gpr_malloc(sizeof(grpc_tcp));
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_log(GPR_DEBUG, "Creating TCP endpoint %p", tcp);
   }
 

src/core/lib/iomgr/tcp_uv.h

@@ -34,7 +34,7 @@
 
 #include <uv.h>
 
-extern grpc_tracer_flag grpc_tcp_trace;
+extern grpc_core::TraceFlag grpc_tcp_trace;
 
 #define GRPC_TCP_DEFAULT_READ_SLICE_SIZE 8192
 

src/core/lib/iomgr/tcp_windows.cc

@@ -49,7 +49,7 @@
 #define GRPC_FIONBIO FIONBIO
 #endif
 
-grpc_tracer_flag grpc_tcp_trace = GRPC_TRACER_INITIALIZER(false, "tcp");
+grpc_core::TraceFlag grpc_tcp_trace(false, "tcp");
 
 static grpc_error *set_non_block(SOCKET sock) {
   int status;
@@ -124,7 +124,7 @@ static void tcp_free(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
 #define TCP_REF(tcp, reason) tcp_ref((tcp), (reason), __FILE__, __LINE__)
 static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
                       const char *reason, const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "TCP unref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
@@ -137,7 +137,7 @@ static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
 
 static void tcp_ref(grpc_tcp *tcp, const char *reason, const char *file,
                     int line) {
-  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+  if (grpc_tcp_trace.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "TCP   ref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,

src/core/lib/iomgr/timer_generic.cc

@@ -44,9 +44,8 @@
 #define MAX_QUEUE_WINDOW_DURATION 1
 
 extern "C" {
-grpc_tracer_flag grpc_timer_trace = GRPC_TRACER_INITIALIZER(false, "timer");
-grpc_tracer_flag grpc_timer_check_trace =
-    GRPC_TRACER_INITIALIZER(false, "timer_check");
+grpc_core::TraceFlag grpc_timer_trace(false, "timer");
+grpc_core::TraceFlag grpc_timer_check_trace(false, "timer_check");
 }
 
 /* A "timer shard". Contains a 'heap' and a 'list' of timers. All timers with
@@ -247,8 +246,6 @@ void grpc_timer_list_init(grpc_exec_ctx *exec_ctx) {
   g_shared_mutables.min_timer = grpc_exec_ctx_now(exec_ctx);
   gpr_tls_init(&g_last_seen_min_timer);
   gpr_tls_set(&g_last_seen_min_timer, 0);
-  grpc_register_tracer(&grpc_timer_trace);
-  grpc_register_tracer(&grpc_timer_check_trace);
 
   for (i = 0; i < NUM_SHARDS; i++) {
     timer_shard *shard = &g_shards[i];
@@ -331,7 +328,7 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
   timer->hash_table_next = NULL;
 #endif
 
-  if (GRPC_TRACER_ON(grpc_timer_trace)) {
+  if (grpc_timer_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "TIMER %p: SET %" PRIdPTR " now %" PRIdPTR " call %p[%p]", timer,
             deadline, grpc_exec_ctx_now(exec_ctx), closure, closure->cb);
@@ -367,7 +364,7 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
     timer->heap_index = INVALID_HEAP_INDEX;
     list_join(&shard->list, timer);
   }
-  if (GRPC_TRACER_ON(grpc_timer_trace)) {
+  if (grpc_timer_trace.enabled()) {
     gpr_log(GPR_DEBUG, "  .. add to shard %d with queue_deadline_cap=%" PRIdPTR
                        " => is_first_timer=%s",
             (int)(shard - g_shards), shard->queue_deadline_cap,
@@ -388,7 +385,7 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
      grpc_timer_check. */
   if (is_first_timer) {
     gpr_mu_lock(&g_shared_mutables.mu);
-    if (GRPC_TRACER_ON(grpc_timer_trace)) {
+    if (grpc_timer_trace.enabled()) {
       gpr_log(GPR_DEBUG, "  .. old shard min_deadline=%" PRIdPTR,
               shard->min_deadline);
     }
@@ -418,7 +415,7 @@ void grpc_timer_cancel(grpc_exec_ctx *exec_ctx, grpc_timer *timer) {
 
   timer_shard *shard = &g_shards[GPR_HASH_POINTER(timer, NUM_SHARDS)];
   gpr_mu_lock(&shard->mu);
-  if (GRPC_TRACER_ON(grpc_timer_trace)) {
+  if (grpc_timer_trace.enabled()) {
     gpr_log(GPR_DEBUG, "TIMER %p: CANCEL pending=%s", timer,
             timer->pending ? "true" : "false");
   }
@@ -459,7 +456,7 @@ static int refill_heap(timer_shard *shard, gpr_atm now) {
       saturating_add(GPR_MAX(now, shard->queue_deadline_cap),
                      (gpr_atm)(deadline_delta * 1000.0));
 
-  if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+  if (grpc_timer_check_trace.enabled()) {
     gpr_log(GPR_DEBUG, "  .. shard[%d]->queue_deadline_cap --> %" PRIdPTR,
             (int)(shard - g_shards), shard->queue_deadline_cap);
   }
@@ -467,7 +464,7 @@ static int refill_heap(timer_shard *shard, gpr_atm now) {
     next = timer->next;
 
     if (timer->deadline < shard->queue_deadline_cap) {
-      if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+      if (grpc_timer_check_trace.enabled()) {
         gpr_log(GPR_DEBUG, "  .. add timer with deadline %" PRIdPTR " to heap",
                 timer->deadline);
       }
@@ -484,7 +481,7 @@ static int refill_heap(timer_shard *shard, gpr_atm now) {
 static grpc_timer *pop_one(timer_shard *shard, gpr_atm now) {
   grpc_timer *timer;
   for (;;) {
-    if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+    if (grpc_timer_check_trace.enabled()) {
       gpr_log(GPR_DEBUG, "  .. shard[%d]: heap_empty=%s",
               (int)(shard - g_shards),
               grpc_timer_heap_is_empty(&shard->heap) ? "true" : "false");
@@ -494,13 +491,13 @@ static grpc_timer *pop_one(timer_shard *shard, gpr_atm now) {
       if (!refill_heap(shard, now)) return NULL;
     }
     timer = grpc_timer_heap_top(&shard->heap);
-    if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+    if (grpc_timer_check_trace.enabled()) {
       gpr_log(GPR_DEBUG,
               "  .. check top timer deadline=%" PRIdPTR " now=%" PRIdPTR,
               timer->deadline, now);
     }
     if (timer->deadline > now) return NULL;
-    if (GRPC_TRACER_ON(grpc_timer_trace)) {
+    if (grpc_timer_trace.enabled()) {
       gpr_log(GPR_DEBUG, "TIMER %p: FIRE %" PRIdPTR "ms late via %s scheduler",
               timer, now - timer->deadline,
               timer->closure->scheduler->vtable->name);
@@ -525,7 +522,7 @@ static size_t pop_timers(grpc_exec_ctx *exec_ctx, timer_shard *shard,
   }
   *new_min_deadline = compute_min_deadline(shard);
   gpr_mu_unlock(&shard->mu);
-  if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+  if (grpc_timer_check_trace.enabled()) {
     gpr_log(GPR_DEBUG, "  .. shard[%d] popped %" PRIdPTR,
             (int)(shard - g_shards), n);
   }
@@ -549,7 +546,7 @@ static grpc_timer_check_result run_some_expired_timers(grpc_exec_ctx *exec_ctx,
     gpr_mu_lock(&g_shared_mutables.mu);
     result = GRPC_TIMERS_CHECKED_AND_EMPTY;
 
-    if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+    if (grpc_timer_check_trace.enabled()) {
       gpr_log(GPR_DEBUG, "  .. shard[%d]->min_deadline = %" PRIdPTR,
               (int)(g_shard_queue[0] - g_shards),
               g_shard_queue[0]->min_deadline);
@@ -567,7 +564,7 @@ static grpc_timer_check_result run_some_expired_timers(grpc_exec_ctx *exec_ctx,
         result = GRPC_TIMERS_FIRED;
       }
 
-      if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+      if (grpc_timer_check_trace.enabled()) {
         gpr_log(GPR_DEBUG,
                 "  .. result --> %d"
                 ", shard[%d]->min_deadline %" PRIdPTR " --> %" PRIdPTR
@@ -612,7 +609,7 @@ grpc_timer_check_result grpc_timer_check(grpc_exec_ctx *exec_ctx,
     if (next != NULL) {
       *next = GPR_MIN(*next, min_timer);
     }
-    if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+    if (grpc_timer_check_trace.enabled()) {
       gpr_log(GPR_DEBUG,
               "TIMER CHECK SKIP: now=%" PRIdPTR " min_timer=%" PRIdPTR, now,
               min_timer);
@@ -626,7 +623,7 @@ grpc_timer_check_result grpc_timer_check(grpc_exec_ctx *exec_ctx,
           : GRPC_ERROR_CREATE_FROM_STATIC_STRING("Shutting down timer system");
 
   // tracing
-  if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+  if (grpc_timer_check_trace.enabled()) {
     char *next_str;
     if (next == NULL) {
       next_str = gpr_strdup("NULL");
@@ -643,7 +640,7 @@ grpc_timer_check_result grpc_timer_check(grpc_exec_ctx *exec_ctx,
   grpc_timer_check_result r =
       run_some_expired_timers(exec_ctx, now, next, shutdown_error);
   // tracing
-  if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+  if (grpc_timer_check_trace.enabled()) {
     char *next_str;
     if (next == NULL) {
       next_str = gpr_strdup("NULL");

src/core/lib/iomgr/timer_manager.cc

@@ -33,7 +33,7 @@ typedef struct completed_thread {
   struct completed_thread *next;
 } completed_thread;
 
-extern "C" grpc_tracer_flag grpc_timer_check_trace;
+extern grpc_core::TraceFlag grpc_timer_check_trace;
 
 // global mutex
 static gpr_mu g_mu;
@@ -81,7 +81,7 @@ static void start_timer_thread_and_unlock(void) {
   ++g_waiter_count;
   ++g_thread_count;
   gpr_mu_unlock(&g_mu);
-  if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+  if (grpc_timer_check_trace.enabled()) {
     gpr_log(GPR_DEBUG, "Spawn timer thread");
   }
   gpr_thd_options opt = gpr_thd_options_default();
@@ -115,7 +115,7 @@ static void run_some_timers(grpc_exec_ctx *exec_ctx) {
     // if there's no thread waiting with a timeout, kick an existing
     // waiter so that the next deadline is not missed
     if (!g_has_timed_waiter) {
-      if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+      if (grpc_timer_check_trace.enabled()) {
         gpr_log(GPR_DEBUG, "kick untimed waiter");
       }
       gpr_cv_signal(&g_cv_wait);
@@ -123,7 +123,7 @@ static void run_some_timers(grpc_exec_ctx *exec_ctx) {
     gpr_mu_unlock(&g_mu);
   }
   // without our lock, flush the exec_ctx
-  if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+  if (grpc_timer_check_trace.enabled()) {
     gpr_log(GPR_DEBUG, "flush exec_ctx");
   }
   grpc_exec_ctx_flush(exec_ctx);
@@ -178,7 +178,7 @@ static bool wait_until(grpc_exec_ctx *exec_ctx, grpc_millis next) {
         g_has_timed_waiter = true;
         g_timed_waiter_deadline = next;
 
-        if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+        if (grpc_timer_check_trace.enabled()) {
           grpc_millis wait_time = next - grpc_exec_ctx_now(exec_ctx);
           gpr_log(GPR_DEBUG, "sleep for a %" PRIdPTR " milliseconds",
                   wait_time);
@@ -188,15 +188,14 @@ static bool wait_until(grpc_exec_ctx *exec_ctx, grpc_millis next) {
       }
     }
 
-    if (GRPC_TRACER_ON(grpc_timer_check_trace) &&
-        next == GRPC_MILLIS_INF_FUTURE) {
+    if (grpc_timer_check_trace.enabled() && next == GRPC_MILLIS_INF_FUTURE) {
       gpr_log(GPR_DEBUG, "sleep until kicked");
     }
 
     gpr_cv_wait(&g_cv_wait, &g_mu,
                 grpc_millis_to_timespec(next, GPR_CLOCK_REALTIME));
 
-    if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+    if (grpc_timer_check_trace.enabled()) {
       gpr_log(GPR_DEBUG, "wait ended: was_timed:%d kicked:%d",
               my_timed_waiter_generation == g_timed_waiter_generation,
               g_kicked);
@@ -240,7 +239,7 @@ static void timer_main_loop(grpc_exec_ctx *exec_ctx) {
 
            Consequently, we can just sleep forever here and be happy at some
            saved wakeup cycles. */
-        if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+        if (grpc_timer_check_trace.enabled()) {
           gpr_log(GPR_DEBUG, "timers not checked: expect another thread to");
         }
         next = GRPC_MILLIS_INF_FUTURE;
@@ -266,7 +265,7 @@ static void timer_thread_cleanup(completed_thread *ct) {
   ct->next = g_completed_threads;
   g_completed_threads = ct;
   gpr_mu_unlock(&g_mu);
-  if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+  if (grpc_timer_check_trace.enabled()) {
     gpr_log(GPR_DEBUG, "End timer thread");
   }
 }
@@ -309,18 +308,18 @@ void grpc_timer_manager_init(void) {
 
 static void stop_threads(void) {
   gpr_mu_lock(&g_mu);
-  if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+  if (grpc_timer_check_trace.enabled()) {
     gpr_log(GPR_DEBUG, "stop timer threads: threaded=%d", g_threaded);
   }
   if (g_threaded) {
     g_threaded = false;
     gpr_cv_broadcast(&g_cv_wait);
-    if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+    if (grpc_timer_check_trace.enabled()) {
       gpr_log(GPR_DEBUG, "num timer threads: %d", g_thread_count);
     }
     while (g_thread_count > 0) {
       gpr_cv_wait(&g_cv_shutdown, &g_mu, gpr_inf_future(GPR_CLOCK_REALTIME));
-      if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+      if (grpc_timer_check_trace.enabled()) {
         gpr_log(GPR_DEBUG, "num timer threads: %d", g_thread_count);
       }
       gc_completed_threads();

src/core/lib/iomgr/timer_uv.cc

@@ -30,9 +30,8 @@
 #include <uv.h>
 
 extern "C" {
-grpc_tracer_flag grpc_timer_trace = GRPC_TRACER_INITIALIZER(false, "timer");
-grpc_tracer_flag grpc_timer_check_trace =
-    GRPC_TRACER_INITIALIZER(false, "timer_check");
+grpc_core::TraceFlag grpc_timer_trace(false, "timer");
+grpc_core::TraceFlag grpc_timer_check_trace(false, "timer_check");
 }
 
 static void timer_close_callback(uv_handle_t *handle) { gpr_free(handle); }

src/core/lib/security/context/security_context.cc

@@ -30,8 +30,8 @@
 #include <grpc/support/string_util.h>
 
 #ifndef NDEBUG
-grpc_tracer_flag grpc_trace_auth_context_refcount =
-    GRPC_TRACER_INITIALIZER(false, "auth_context_refcount");
+grpc_core::TraceFlag grpc_trace_auth_context_refcount(false,
+                                                   "auth_context_refcount");
 #endif
 
 /* --- grpc_call --- */
@@ -135,7 +135,7 @@ grpc_auth_context *grpc_auth_context_ref(grpc_auth_context *ctx,
                                          const char *file, int line,
                                          const char *reason) {
   if (ctx == NULL) return NULL;
-  if (GRPC_TRACER_ON(grpc_trace_auth_context_refcount)) {
+  if (grpc_trace_auth_context_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&ctx->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "AUTH_CONTEXT:%p   ref %" PRIdPTR " -> %" PRIdPTR " %s", ctx, val,
@@ -153,7 +153,7 @@ grpc_auth_context *grpc_auth_context_ref(grpc_auth_context *ctx) {
 void grpc_auth_context_unref(grpc_auth_context *ctx, const char *file, int line,
                              const char *reason) {
   if (ctx == NULL) return;
-  if (GRPC_TRACER_ON(grpc_trace_auth_context_refcount)) {
+  if (grpc_trace_auth_context_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&ctx->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "AUTH_CONTEXT:%p unref %" PRIdPTR " -> %" PRIdPTR " %s", ctx, val,

src/core/lib/security/context/security_context.h

@@ -23,7 +23,7 @@
 #include "src/core/lib/security/credentials/credentials.h"
 
 #ifndef NDEBUG
-extern grpc_tracer_flag grpc_trace_auth_context_refcount;
+extern grpc_core::TraceFlag grpc_trace_auth_context_refcount;
 #endif
 
 #ifdef __cplusplus

src/core/lib/security/credentials/jwt/jwt_credentials.cc

@@ -172,7 +172,7 @@ static char *redact_private_key(const char *json_key) {
 
 grpc_call_credentials *grpc_service_account_jwt_access_credentials_create(
     const char *json_key, gpr_timespec token_lifetime, void *reserved) {
-  if (GRPC_TRACER_ON(grpc_api_trace)) {
+  if (grpc_api_trace.enabled()) {
     char *clean_json = redact_private_key(json_key);
     gpr_log(GPR_INFO,
             "grpc_service_account_jwt_access_credentials_create("

src/core/lib/security/credentials/oauth2/oauth2_credentials.cc

@@ -467,7 +467,7 @@ grpc_call_credentials *grpc_google_refresh_token_credentials_create(
     const char *json_refresh_token, void *reserved) {
   grpc_auth_refresh_token token =
       grpc_auth_refresh_token_create_from_string(json_refresh_token);
-  if (GRPC_TRACER_ON(grpc_api_trace)) {
+  if (grpc_api_trace.enabled()) {
     char *loggable_token = create_loggable_refresh_token(&token);
     gpr_log(GPR_INFO,
             "grpc_refresh_token_credentials_create(json_refresh_token=%s, "

src/core/lib/security/credentials/plugin/plugin_credentials.cc

@@ -31,8 +31,7 @@
 #include "src/core/lib/surface/api_trace.h"
 #include "src/core/lib/surface/validate_metadata.h"
 
-grpc_tracer_flag grpc_plugin_credentials_trace =
-    GRPC_TRACER_INITIALIZER(false, "plugin_credentials");
+grpc_core::TraceFlag grpc_plugin_credentials_trace(false, "plugin_credentials");
 
 static void plugin_destruct(grpc_exec_ctx *exec_ctx,
                             grpc_call_credentials *creds) {
@@ -123,7 +122,7 @@ static void plugin_md_request_metadata_ready(void *request,
       NULL, NULL);
   grpc_plugin_credentials_pending_request *r =
       (grpc_plugin_credentials_pending_request *)request;
-  if (GRPC_TRACER_ON(grpc_plugin_credentials_trace)) {
+  if (grpc_plugin_credentials_trace.enabled()) {
     gpr_log(GPR_INFO,
             "plugin_credentials[%p]: request %p: plugin returned "
             "asynchronously",
@@ -136,7 +135,7 @@ static void plugin_md_request_metadata_ready(void *request,
     grpc_error *error =
         process_plugin_result(&exec_ctx, r, md, num_md, status, error_details);
     GRPC_CLOSURE_SCHED(&exec_ctx, r->on_request_metadata, error);
-  } else if (GRPC_TRACER_ON(grpc_plugin_credentials_trace)) {
+  } else if (grpc_plugin_credentials_trace.enabled()) {
     gpr_log(GPR_INFO,
             "plugin_credentials[%p]: request %p: plugin was previously "
             "cancelled",
@@ -172,7 +171,7 @@ static bool plugin_get_request_metadata(grpc_exec_ctx *exec_ctx,
     c->pending_requests = pending_request;
     gpr_mu_unlock(&c->mu);
     // Invoke the plugin.  The callback holds a ref to us.
-    if (GRPC_TRACER_ON(grpc_plugin_credentials_trace)) {
+    if (grpc_plugin_credentials_trace.enabled()) {
       gpr_log(GPR_INFO, "plugin_credentials[%p]: request %p: invoking plugin",
               c, pending_request);
     }
@@ -185,7 +184,7 @@ static bool plugin_get_request_metadata(grpc_exec_ctx *exec_ctx,
                                 plugin_md_request_metadata_ready,
                                 pending_request, creds_md, &num_creds_md,
                                 &status, &error_details)) {
-      if (GRPC_TRACER_ON(grpc_plugin_credentials_trace)) {
+      if (grpc_plugin_credentials_trace.enabled()) {
         gpr_log(GPR_INFO,
                 "plugin_credentials[%p]: request %p: plugin will return "
                 "asynchronously",
@@ -200,7 +199,7 @@ static bool plugin_get_request_metadata(grpc_exec_ctx *exec_ctx,
     // asynchronously by plugin_cancel_get_request_metadata(), so return
     // false.  Otherwise, process the result.
     if (pending_request->cancelled) {
-      if (GRPC_TRACER_ON(grpc_plugin_credentials_trace)) {
+      if (grpc_plugin_credentials_trace.enabled()) {
         gpr_log(GPR_INFO,
                 "plugin_credentials[%p]: request %p was cancelled, error "
                 "will be returned asynchronously",
@@ -208,7 +207,7 @@ static bool plugin_get_request_metadata(grpc_exec_ctx *exec_ctx,
       }
       retval = false;
     } else {
-      if (GRPC_TRACER_ON(grpc_plugin_credentials_trace)) {
+      if (grpc_plugin_credentials_trace.enabled()) {
         gpr_log(GPR_INFO,
                 "plugin_credentials[%p]: request %p: plugin returned "
                 "synchronously",
@@ -237,7 +236,7 @@ static void plugin_cancel_get_request_metadata(
            c->pending_requests;
        pending_request != NULL; pending_request = pending_request->next) {
     if (pending_request->md_array == md_array) {
-      if (GRPC_TRACER_ON(grpc_plugin_credentials_trace)) {
+      if (grpc_plugin_credentials_trace.enabled()) {
         gpr_log(GPR_INFO, "plugin_credentials[%p]: cancelling request %p", c,
                 pending_request);
       }

src/core/lib/security/credentials/plugin/plugin_credentials.h

@@ -21,7 +21,7 @@
 
 #include "src/core/lib/security/credentials/credentials.h"
 
-extern grpc_tracer_flag grpc_plugin_credentials_trace;
+extern grpc_core::TraceFlag grpc_plugin_credentials_trace;
 
 struct grpc_plugin_credentials;
 

src/core/lib/security/transport/secure_endpoint.cc

@@ -61,8 +61,7 @@ typedef struct {
   gpr_refcount ref;
 } secure_endpoint;
 
-grpc_tracer_flag grpc_trace_secure_endpoint =
-    GRPC_TRACER_INITIALIZER(false, "secure_endpoint");
+grpc_core::TraceFlag grpc_trace_secure_endpoint(false, "secure_endpoint");
 
 static void destroy(grpc_exec_ctx *exec_ctx, secure_endpoint *secure_ep) {
   secure_endpoint *ep = secure_ep;
@@ -86,7 +85,7 @@ static void destroy(grpc_exec_ctx *exec_ctx, secure_endpoint *secure_ep) {
 static void secure_endpoint_unref(grpc_exec_ctx *exec_ctx, secure_endpoint *ep,
                                   const char *reason, const char *file,
                                   int line) {
-  if (GRPC_TRACER_ON(grpc_trace_secure_endpoint)) {
+  if (grpc_trace_secure_endpoint.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&ep->ref.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "SECENDP unref %p : %s %" PRIdPTR " -> %" PRIdPTR, ep, reason, val,
@@ -99,7 +98,7 @@ static void secure_endpoint_unref(grpc_exec_ctx *exec_ctx, secure_endpoint *ep,
 
 static void secure_endpoint_ref(secure_endpoint *ep, const char *reason,
                                 const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_trace_secure_endpoint)) {
+  if (grpc_trace_secure_endpoint.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&ep->ref.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "SECENDP   ref %p : %s %" PRIdPTR " -> %" PRIdPTR, ep, reason, val,
@@ -131,7 +130,7 @@ static void flush_read_staging_buffer(secure_endpoint *ep, uint8_t **cur,
 
 static void call_read_cb(grpc_exec_ctx *exec_ctx, secure_endpoint *ep,
                          grpc_error *error) {
-  if (GRPC_TRACER_ON(grpc_trace_secure_endpoint)) {
+  if (grpc_trace_secure_endpoint.enabled()) {
     size_t i;
     for (i = 0; i < ep->read_buffer->count; i++) {
       char *data = grpc_dump_slice(ep->read_buffer->slices[i],
@@ -270,7 +269,7 @@ static void endpoint_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *secure_ep,
 
   grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &ep->output_buffer);
 
-  if (GRPC_TRACER_ON(grpc_trace_secure_endpoint)) {
+  if (grpc_trace_secure_endpoint.enabled()) {
     for (i = 0; i < slices->count; i++) {
       char *data =
           grpc_dump_slice(slices->slices[i], GPR_DUMP_HEX | GPR_DUMP_ASCII);

src/core/lib/security/transport/secure_endpoint.h

@@ -29,7 +29,7 @@ extern "C" {
 struct tsi_frame_protector;
 struct tsi_zero_copy_grpc_protector;
 
-extern grpc_tracer_flag grpc_trace_secure_endpoint;
+extern grpc_core::TraceFlag grpc_trace_secure_endpoint;
 
 /* Takes ownership of protector, zero_copy_protector, and to_wrap, and refs
  * leftover_slices. If zero_copy_protector is not NULL, protector will never be

src/core/lib/security/transport/security_connector.cc

@@ -44,8 +44,8 @@
 #include "src/core/tsi/transport_security_adapter.h"
 
 #ifndef NDEBUG
-grpc_tracer_flag grpc_trace_security_connector_refcount =
-    GRPC_TRACER_INITIALIZER(false, "security_connector_refcount");
+grpc_core::TraceFlag grpc_trace_security_connector_refcount(
+    false, "security_connector_refcount");
 #endif
 
 /* -- Constants. -- */
@@ -197,7 +197,7 @@ grpc_security_connector *grpc_security_connector_ref(
     grpc_security_connector *sc, const char *file, int line,
     const char *reason) {
   if (sc == NULL) return NULL;
-  if (GRPC_TRACER_ON(grpc_trace_security_connector_refcount)) {
+  if (grpc_trace_security_connector_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&sc->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "SECURITY_CONNECTOR:%p   ref %" PRIdPTR " -> %" PRIdPTR " %s", sc,
@@ -218,7 +218,7 @@ void grpc_security_connector_unref(grpc_exec_ctx *exec_ctx,
                                    const char *file, int line,
                                    const char *reason) {
   if (sc == NULL) return;
-  if (GRPC_TRACER_ON(grpc_trace_security_connector_refcount)) {
+  if (grpc_trace_security_connector_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&sc->refcount.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "SECURITY_CONNECTOR:%p unref %" PRIdPTR " -> %" PRIdPTR " %s", sc,

src/core/lib/security/transport/security_connector.h

@@ -34,7 +34,7 @@ extern "C" {
 #endif
 
 #ifndef NDEBUG
-extern grpc_tracer_flag grpc_trace_security_connector_refcount;
+extern grpc_core::TraceFlag grpc_trace_security_connector_refcount;
 #endif
 
 /* --- status enum. --- */

src/core/lib/surface/alarm.cc

@@ -28,8 +28,7 @@
 #include "src/core/lib/surface/completion_queue.h"
 
 #ifndef NDEBUG
-grpc_tracer_flag grpc_trace_alarm_refcount =
-    GRPC_TRACER_INITIALIZER(false, "alarm_refcount");
+grpc_core::TraceFlag grpc_trace_alarm_refcount(false, "alarm_refcount");
 #endif
 
 struct grpc_alarm {
@@ -59,7 +58,7 @@ static void alarm_unref(grpc_alarm *alarm) {
 #ifndef NDEBUG
 static void alarm_ref_dbg(grpc_alarm *alarm, const char *reason,
                           const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_trace_alarm_refcount)) {
+  if (grpc_trace_alarm_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&alarm->refs.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "Alarm:%p  ref %" PRIdPTR " -> %" PRIdPTR " %s", alarm, val,
@@ -71,7 +70,7 @@ static void alarm_ref_dbg(grpc_alarm *alarm, const char *reason,
 
 static void alarm_unref_dbg(grpc_alarm *alarm, const char *reason,
                             const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_trace_alarm_refcount)) {
+  if (grpc_trace_alarm_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&alarm->refs.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "Alarm:%p  Unref %" PRIdPTR " -> %" PRIdPTR " %s", alarm, val,
@@ -103,7 +102,7 @@ grpc_alarm *grpc_alarm_create(void *reserved) {
   grpc_alarm *alarm = (grpc_alarm *)gpr_malloc(sizeof(grpc_alarm));
 
 #ifndef NDEBUG
-  if (GRPC_TRACER_ON(grpc_trace_alarm_refcount)) {
+  if (grpc_trace_alarm_refcount.enabled()) {
     gpr_log(GPR_DEBUG, "Alarm:%p created (ref: 1)", alarm);
   }
 #endif

src/core/lib/surface/alarm_internal.h

@@ -28,7 +28,7 @@ extern "C" {
 
 #ifndef NDEBUG
 
-extern grpc_tracer_flag grpc_trace_alarm_refcount;
+extern grpc_core::TraceFlag grpc_trace_alarm_refcount;
 
 #define GRPC_ALARM_REF(a, reason) alarm_ref_dbg(a, reason, __FILE__, __LINE__)
 #define GRPC_ALARM_UNREF(a, reason) \

src/core/lib/surface/api_trace.cc

@@ -19,4 +19,4 @@
 #include "src/core/lib/surface/api_trace.h"
 #include "src/core/lib/debug/trace.h"
 
-grpc_tracer_flag grpc_api_trace = GRPC_TRACER_INITIALIZER(false, "api");
+grpc_core::TraceFlag grpc_api_trace(false, "api");

src/core/lib/surface/api_trace.h

@@ -26,7 +26,7 @@
 extern "C" {
 #endif
 
-extern grpc_tracer_flag grpc_api_trace;
+extern grpc_core::TraceFlag grpc_api_trace;
 
 /* Provide unwrapping macros because we're in C89 and variadic macros weren't
    introduced until C99... */
@@ -47,7 +47,7 @@ extern grpc_tracer_flag grpc_api_trace;
 /* Due to the limitations of C89's preprocessor, the arity of the var-arg list
    'nargs' must be specified. */
 #define GRPC_API_TRACE(fmt, nargs, args)                      \
-  if (GRPC_TRACER_ON(grpc_api_trace)) {                       \
+  if (grpc_api_trace.enabled()) {                             \
     gpr_log(GPR_INFO, fmt GRPC_API_TRACE_UNWRAP##nargs args); \
   }
 

src/core/lib/surface/call.cc

@@ -259,10 +259,8 @@ struct grpc_call {
   gpr_atm recv_state;
 };
 
-grpc_tracer_flag grpc_call_error_trace =
-    GRPC_TRACER_INITIALIZER(false, "call_error");
-grpc_tracer_flag grpc_compression_trace =
-    GRPC_TRACER_INITIALIZER(false, "compression");
+grpc_core::TraceFlag grpc_call_error_trace(false, "call_error");
+grpc_core::TraceFlag grpc_compression_trace(false, "compression");
 
 #define CALL_STACK_FROM_CALL(call) ((grpc_call_stack *)((call) + 1))
 #define CALL_FROM_CALL_STACK(call_stack) (((grpc_call *)(call_stack)) - 1)
@@ -764,7 +762,7 @@ static void get_final_status(grpc_exec_ctx *exec_ctx, grpc_call *call,
   for (i = 0; i < STATUS_SOURCE_COUNT; i++) {
     status[i] = unpack_received_status(gpr_atm_acq_load(&call->status[i]));
   }
-  if (GRPC_TRACER_ON(grpc_call_error_trace)) {
+  if (grpc_call_error_trace.enabled()) {
     gpr_log(GPR_DEBUG, "get_final_status %s", call->is_client ? "CLI" : "SVR");
     for (i = 0; i < STATUS_SOURCE_COUNT; i++) {
       if (status[i].is_set) {
@@ -1426,7 +1424,7 @@ static void receiving_slice_ready(grpc_exec_ctx *exec_ctx, void *bctlp,
   }
 
   if (error != GRPC_ERROR_NONE) {
-    if (GRPC_TRACER_ON(grpc_trace_operation_failures)) {
+    if (grpc_trace_operation_failures.enabled()) {
       GRPC_LOG_IF_ERROR("receiving_slice_ready", GRPC_ERROR_REF(error));
     }
     grpc_byte_stream_destroy(exec_ctx, call->receiving_stream);
@@ -1530,7 +1528,7 @@ static void validate_filtered_metadata(grpc_exec_ctx *exec_ctx,
     GPR_ASSERT(call->stream_encodings_accepted_by_peer != 0);
     if (!GPR_BITGET(call->stream_encodings_accepted_by_peer,
                     call->incoming_stream_compression_algorithm)) {
-      if (GRPC_TRACER_ON(grpc_compression_trace)) {
+      if (grpc_compression_trace.enabled()) {
         const char *algo_name = NULL;
         grpc_stream_compression_algorithm_name(
             call->incoming_stream_compression_algorithm, &algo_name);
@@ -1573,7 +1571,7 @@ static void validate_filtered_metadata(grpc_exec_ctx *exec_ctx,
     GPR_ASSERT(call->encodings_accepted_by_peer != 0);
     if (!GPR_BITGET(call->encodings_accepted_by_peer,
                     call->incoming_compression_algorithm)) {
-      if (GRPC_TRACER_ON(grpc_compression_trace)) {
+      if (grpc_compression_trace.enabled()) {
         const char *algo_name = NULL;
         grpc_compression_algorithm_name(call->incoming_compression_algorithm,
                                         &algo_name);

src/core/lib/surface/call.h

@@ -102,8 +102,7 @@ void grpc_call_context_set(grpc_call *call, grpc_context_index elem,
 void *grpc_call_context_get(grpc_call *call, grpc_context_index elem);
 
 #define GRPC_CALL_LOG_BATCH(sev, call, ops, nops, tag) \
-  if (GRPC_TRACER_ON(grpc_api_trace))                  \
-  grpc_call_log_batch(sev, call, ops, nops, tag)
+  if (grpc_api_trace.enabled()) grpc_call_log_batch(sev, call, ops, nops, tag)
 
 uint8_t grpc_call_is_client(grpc_call *call);
 
@@ -112,8 +111,8 @@ uint8_t grpc_call_is_client(grpc_call *call);
 grpc_compression_algorithm grpc_call_compression_for_level(
     grpc_call *call, grpc_compression_level level);
 
-extern grpc_tracer_flag grpc_call_error_trace;
-extern grpc_tracer_flag grpc_compression_trace;
+extern grpc_core::TraceFlag grpc_call_error_trace;
+extern grpc_core::TraceFlag grpc_compression_trace;
 
 #ifdef __cplusplus
 }

src/core/lib/surface/completion_queue.cc

@@ -39,13 +39,10 @@
 #include "src/core/lib/surface/call.h"
 #include "src/core/lib/surface/event_string.h"
 
-grpc_tracer_flag grpc_trace_operation_failures =
-    GRPC_TRACER_INITIALIZER(false, "op_failure");
+grpc_core::TraceFlag grpc_trace_operation_failures(false, "op_failure");
 #ifndef NDEBUG
-grpc_tracer_flag grpc_trace_pending_tags =
-    GRPC_TRACER_INITIALIZER(false, "pending_tags");
-grpc_tracer_flag grpc_trace_cq_refcount =
-    GRPC_TRACER_INITIALIZER(false, "cq_refcount");
+grpc_core::TraceFlag grpc_trace_pending_tags(false, "pending_tags");
+grpc_core::TraceFlag grpc_trace_cq_refcount(false, "cq_refcount");
 #endif
 
 typedef struct {
@@ -328,14 +325,11 @@ static const cq_vtable g_cq_vtable[] = {
 #define POLLSET_FROM_CQ(cq) \
   ((grpc_pollset *)(cq->vtable->data_size + (char *)DATA_FROM_CQ(cq)))
 
-grpc_tracer_flag grpc_cq_pluck_trace =
-    GRPC_TRACER_INITIALIZER(true, "queue_pluck");
-grpc_tracer_flag grpc_cq_event_timeout_trace =
-    GRPC_TRACER_INITIALIZER(true, "queue_timeout");
+grpc_core::TraceFlag grpc_cq_pluck_trace(true, "queue_pluck");
+grpc_core::TraceFlag grpc_cq_event_timeout_trace(true, "queue_timeout");
 
 #define GRPC_SURFACE_TRACE_RETURNED_EVENT(cq, event)                       \
-  if (GRPC_TRACER_ON(grpc_api_trace) &&                 \
-      (GRPC_TRACER_ON(grpc_cq_pluck_trace) ||           \
+  if (grpc_api_trace.enabled() && (grpc_cq_pluck_trace.enabled() ||        \
                                    (event)->type != GRPC_QUEUE_TIMEOUT)) { \
     char *_ev = grpc_event_string(event);                                  \
     gpr_log(GPR_INFO, "RETURN_EVENT[%p]: %s", cq, _ev);                    \
@@ -481,7 +475,7 @@ int grpc_get_cq_poll_num(grpc_completion_queue *cq) {
 #ifndef NDEBUG
 void grpc_cq_internal_ref(grpc_completion_queue *cq, const char *reason,
                           const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_trace_cq_refcount)) {
+  if (grpc_trace_cq_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&cq->owning_refs.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "CQ:%p   ref %" PRIdPTR " -> %" PRIdPTR " %s", cq, val, val + 1,
@@ -502,7 +496,7 @@ static void on_pollset_shutdown_done(grpc_exec_ctx *exec_ctx, void *arg,
 #ifndef NDEBUG
 void grpc_cq_internal_unref(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cq,
                             const char *reason, const char *file, int line) {
-  if (GRPC_TRACER_ON(grpc_trace_cq_refcount)) {
+  if (grpc_trace_cq_refcount.enabled()) {
     gpr_atm val = gpr_atm_no_barrier_load(&cq->owning_refs.count);
     gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
             "CQ:%p unref %" PRIdPTR " -> %" PRIdPTR " %s", cq, val, val - 1,
@@ -604,16 +598,14 @@ static void cq_end_op_for_next(grpc_exec_ctx *exec_ctx,
                                void *done_arg, grpc_cq_completion *storage) {
   GPR_TIMER_BEGIN("cq_end_op_for_next", 0);
 
-  if (GRPC_TRACER_ON(grpc_api_trace) ||
-      (GRPC_TRACER_ON(grpc_trace_operation_failures) &&
-       error != GRPC_ERROR_NONE)) {
+  if (grpc_api_trace.enabled() ||
+      (grpc_trace_operation_failures.enabled() && error != GRPC_ERROR_NONE)) {
     const char *errmsg = grpc_error_string(error);
     GRPC_API_TRACE(
         "cq_end_op_for_next(exec_ctx=%p, cq=%p, tag=%p, error=%s, "
         "done=%p, done_arg=%p, storage=%p)",
         7, (exec_ctx, cq, tag, errmsg, done, done_arg, storage));
-    if (GRPC_TRACER_ON(grpc_trace_operation_failures) &&
-        error != GRPC_ERROR_NONE) {
+    if (grpc_trace_operation_failures.enabled() && error != GRPC_ERROR_NONE) {
       gpr_log(GPR_ERROR, "Operation failed: tag=%p, error=%s", tag, errmsg);
     }
   }
@@ -688,16 +680,14 @@ static void cq_end_op_for_pluck(grpc_exec_ctx *exec_ctx,
 
   GPR_TIMER_BEGIN("cq_end_op_for_pluck", 0);
 
-  if (GRPC_TRACER_ON(grpc_api_trace) ||
-      (GRPC_TRACER_ON(grpc_trace_operation_failures) &&
-       error != GRPC_ERROR_NONE)) {
+  if (grpc_api_trace.enabled() ||
+      (grpc_trace_operation_failures.enabled() && error != GRPC_ERROR_NONE)) {
     const char *errmsg = grpc_error_string(error);
     GRPC_API_TRACE(
         "cq_end_op_for_pluck(exec_ctx=%p, cq=%p, tag=%p, error=%s, "
         "done=%p, done_arg=%p, storage=%p)",
         7, (exec_ctx, cq, tag, errmsg, done, done_arg, storage));
-    if (GRPC_TRACER_ON(grpc_trace_operation_failures) &&
-        error != GRPC_ERROR_NONE) {
+    if (grpc_trace_operation_failures.enabled() && error != GRPC_ERROR_NONE) {
       gpr_log(GPR_ERROR, "Operation failed: tag=%p, error=%s", tag, errmsg);
     }
   }
@@ -791,7 +781,7 @@ static bool cq_is_next_finished(grpc_exec_ctx *exec_ctx, void *arg) {
 
 #ifndef NDEBUG
 static void dump_pending_tags(grpc_completion_queue *cq) {
-  if (!GRPC_TRACER_ON(grpc_trace_pending_tags)) return;
+  if (!grpc_trace_pending_tags.enabled()) return;
 
   gpr_strvec v;
   gpr_strvec_init(&v);
@@ -1054,7 +1044,7 @@ static grpc_event cq_pluck(grpc_completion_queue *cq, void *tag,
 
   GPR_TIMER_BEGIN("grpc_completion_queue_pluck", 0);
 
-  if (GRPC_TRACER_ON(grpc_cq_pluck_trace)) {
+  if (grpc_cq_pluck_trace.enabled()) {
     GRPC_API_TRACE(
         "grpc_completion_queue_pluck("
         "cq=%p, tag=%p, "

src/core/lib/surface/completion_queue.h

@@ -27,13 +27,13 @@
 
 /* These trace flags default to 1. The corresponding lines are only traced
    if grpc_api_trace is also truthy */
-extern grpc_tracer_flag grpc_cq_pluck_trace;
-extern grpc_tracer_flag grpc_cq_event_timeout_trace;
-extern grpc_tracer_flag grpc_trace_operation_failures;
+extern grpc_core::TraceFlag grpc_cq_pluck_trace;
+extern grpc_core::TraceFlag grpc_cq_event_timeout_trace;
+extern grpc_core::TraceFlag grpc_trace_operation_failures;
 
 #ifndef NDEBUG
-extern grpc_tracer_flag grpc_trace_pending_tags;
-extern grpc_tracer_flag grpc_trace_cq_refcount;
+extern grpc_core::TraceFlag grpc_trace_pending_tags;
+extern grpc_core::TraceFlag grpc_trace_cq_refcount;
 #endif
 
 #ifdef __cplusplus

src/core/lib/surface/init.cc

@@ -125,29 +125,9 @@ void grpc_init(void) {
     grpc_slice_intern_init();
     grpc_mdctx_global_init();
     grpc_channel_init_init();
-    grpc_register_tracer(&grpc_api_trace);
-    grpc_register_tracer(&grpc_trace_channel);
-    grpc_register_tracer(&grpc_connectivity_state_trace);
-    grpc_register_tracer(&grpc_trace_channel_stack_builder);
-    grpc_register_tracer(&grpc_http1_trace);
-    grpc_register_tracer(&grpc_cq_pluck_trace);  // default on
-    grpc_register_tracer(&grpc_call_combiner_trace);
-    grpc_register_tracer(&grpc_combiner_trace);
-    grpc_register_tracer(&grpc_server_channel_trace);
-    grpc_register_tracer(&grpc_bdp_estimator_trace);
-    grpc_register_tracer(&grpc_cq_event_timeout_trace);  // default on
-    grpc_register_tracer(&grpc_trace_operation_failures);
-    grpc_register_tracer(&grpc_resource_quota_trace);
-    grpc_register_tracer(&grpc_call_error_trace);
+
 #ifndef NDEBUG
-    grpc_register_tracer(&grpc_trace_pending_tags);
-    grpc_register_tracer(&grpc_trace_alarm_refcount);
-    grpc_register_tracer(&grpc_trace_cq_refcount);
-    grpc_register_tracer(&grpc_trace_closure);
-    grpc_register_tracer(&grpc_trace_error_refcount);
-    grpc_register_tracer(&grpc_trace_stream_refcount);
-    grpc_register_tracer(&grpc_trace_fd_refcount);
-    grpc_register_tracer(&grpc_trace_metadata);
+
 #endif
     grpc_security_pre_init();
     grpc_iomgr_init(&exec_ctx);

src/core/lib/surface/init_secure.cc

@@ -38,11 +38,8 @@
 #endif
 
 void grpc_security_pre_init(void) {
-  grpc_register_tracer(&grpc_trace_secure_endpoint);
-  grpc_register_tracer(&tsi_tracing_enabled);
 #ifndef NDEBUG
-  grpc_register_tracer(&grpc_trace_auth_context_refcount);
-  grpc_register_tracer(&grpc_trace_security_connector_refcount);
+
 #endif
 }
 
@@ -85,7 +82,4 @@ void grpc_register_security_filters(void) {
                                    maybe_prepend_server_auth_filter, NULL);
 }
 
-void grpc_security_init() {
-  grpc_security_register_handshaker_factories();
-  grpc_register_tracer(&grpc_plugin_credentials_trace);
-}
+void grpc_security_init() { grpc_security_register_handshaker_factories(); }

src/core/lib/surface/server.cc

@@ -59,8 +59,7 @@ typedef struct registered_method registered_method;
 
 typedef enum { BATCH_CALL, REGISTERED_CALL } requested_call_type;
 
-grpc_tracer_flag grpc_server_channel_trace =
-    GRPC_TRACER_INITIALIZER(false, "server_channel");
+grpc_core::TraceFlag grpc_server_channel_trace(false, "server_channel");
 
 typedef struct requested_call {
   requested_call_type type;
@@ -445,7 +444,7 @@ static void destroy_channel(grpc_exec_ctx *exec_ctx, channel_data *chand,
   GRPC_CLOSURE_INIT(&chand->finish_destroy_channel_closure,
                     finish_destroy_channel, chand, grpc_schedule_on_exec_ctx);
 
-  if (GRPC_TRACER_ON(grpc_server_channel_trace) && error != GRPC_ERROR_NONE) {
+  if (grpc_server_channel_trace.enabled() && error != GRPC_ERROR_NONE) {
     const char *msg = grpc_error_string(error);
     gpr_log(GPR_INFO, "Disconnected client: %s", msg);
   }

src/core/lib/surface/server.h

@@ -31,7 +31,7 @@ extern "C" {
 extern const grpc_channel_filter grpc_server_top_filter;
 
 /** Lightweight tracing of server channel state */
-extern grpc_tracer_flag grpc_server_channel_trace;
+extern grpc_core::TraceFlag grpc_server_channel_trace;
 
 /* Add a listener to the server: when the server starts, it will call start,
    and when it shuts down, it will call destroy */

src/core/lib/transport/bdp_estimator.cc

@@ -23,8 +23,7 @@
 
 #include <grpc/support/useful.h>
 
-grpc_tracer_flag grpc_bdp_estimator_trace =
-    GRPC_TRACER_INITIALIZER(false, "bdp_estimator");
+grpc_core::TraceFlag grpc_bdp_estimator_trace(false, "bdp_estimator");
 
 namespace grpc_core {
 
@@ -44,7 +43,7 @@ grpc_millis BdpEstimator::CompletePing(grpc_exec_ctx *exec_ctx) {
   double dt = (double)dt_ts.tv_sec + 1e-9 * (double)dt_ts.tv_nsec;
   double bw = dt > 0 ? ((double)accumulator_ / dt) : 0;
   int start_inter_ping_delay = inter_ping_delay_;
-  if (GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+  if (grpc_bdp_estimator_trace.enabled()) {
     gpr_log(GPR_DEBUG, "bdp[%s]:complete acc=%" PRId64 " est=%" PRId64
                        " dt=%lf bw=%lfMbs bw_est=%lfMbs",
             name_, accumulator_, estimate_, dt, bw / 125000.0,
@@ -54,7 +53,7 @@ grpc_millis BdpEstimator::CompletePing(grpc_exec_ctx *exec_ctx) {
   if (accumulator_ > 2 * estimate_ / 3 && bw > bw_est_) {
     estimate_ = GPR_MAX(accumulator_, estimate_ * 2);
     bw_est_ = bw;
-    if (GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+    if (grpc_bdp_estimator_trace.enabled()) {
       gpr_log(GPR_DEBUG, "bdp[%s]: estimate increased to %" PRId64, name_,
               estimate_);
     }
@@ -71,7 +70,7 @@ grpc_millis BdpEstimator::CompletePing(grpc_exec_ctx *exec_ctx) {
   }
   if (start_inter_ping_delay != inter_ping_delay_) {
     stable_estimate_count_ = 0;
-    if (GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+    if (grpc_bdp_estimator_trace.enabled()) {
       gpr_log(GPR_DEBUG, "bdp[%s]:update_inter_time to %dms", name_,
               inter_ping_delay_);
     }

src/core/lib/transport/bdp_estimator.h

@@ -31,7 +31,7 @@
 #include "src/core/lib/debug/trace.h"
 #include "src/core/lib/iomgr/exec_ctx.h"
 
-extern grpc_tracer_flag grpc_bdp_estimator_trace;
+extern grpc_core::TraceFlag grpc_bdp_estimator_trace;
 
 namespace grpc_core {
 
@@ -49,7 +49,7 @@ class BdpEstimator {
   // grpc_bdp_estimator_add_incoming_bytes once a ping has been scheduled by a
   // transport (but not necessarily started)
   void SchedulePing() {
-    if (GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+    if (grpc_bdp_estimator_trace.enabled()) {
       gpr_log(GPR_DEBUG, "bdp[%s]:sched acc=%" PRId64 " est=%" PRId64, name_,
               accumulator_, estimate_);
     }
@@ -62,7 +62,7 @@ class BdpEstimator {
   // once
   // the ping is on the wire
   void StartPing() {
-    if (GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+    if (grpc_bdp_estimator_trace.enabled()) {
       gpr_log(GPR_DEBUG, "bdp[%s]:start acc=%" PRId64 " est=%" PRId64, name_,
               accumulator_, estimate_);
     }

src/core/lib/transport/connectivity_state.cc

@@ -24,8 +24,7 @@
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 
-grpc_tracer_flag grpc_connectivity_state_trace =
-    GRPC_TRACER_INITIALIZER(false, "connectivity_state");
+grpc_core::TraceFlag grpc_connectivity_state_trace(false, "connectivity_state");
 
 const char *grpc_connectivity_state_name(grpc_connectivity_state state) {
   switch (state) {
@@ -80,7 +79,7 @@ grpc_connectivity_state grpc_connectivity_state_check(
   grpc_connectivity_state cur =
       (grpc_connectivity_state)gpr_atm_no_barrier_load(
           &tracker->current_state_atm);
-  if (GRPC_TRACER_ON(grpc_connectivity_state_trace)) {
+  if (grpc_connectivity_state_trace.enabled()) {
     gpr_log(GPR_DEBUG, "CONWATCH: %p %s: get %s", tracker, tracker->name,
             grpc_connectivity_state_name(cur));
   }
@@ -92,7 +91,7 @@ grpc_connectivity_state grpc_connectivity_state_get(
   grpc_connectivity_state cur =
       (grpc_connectivity_state)gpr_atm_no_barrier_load(
           &tracker->current_state_atm);
-  if (GRPC_TRACER_ON(grpc_connectivity_state_trace)) {
+  if (grpc_connectivity_state_trace.enabled()) {
     gpr_log(GPR_DEBUG, "CONWATCH: %p %s: get %s", tracker, tracker->name,
             grpc_connectivity_state_name(cur));
   }
@@ -113,7 +112,7 @@ bool grpc_connectivity_state_notify_on_state_change(
   grpc_connectivity_state cur =
       (grpc_connectivity_state)gpr_atm_no_barrier_load(
           &tracker->current_state_atm);
-  if (GRPC_TRACER_ON(grpc_connectivity_state_trace)) {
+  if (grpc_connectivity_state_trace.enabled()) {
     if (current == NULL) {
       gpr_log(GPR_DEBUG, "CONWATCH: %p %s: unsubscribe notify=%p", tracker,
               tracker->name, notify);
@@ -167,7 +166,7 @@ void grpc_connectivity_state_set(grpc_exec_ctx *exec_ctx,
       (grpc_connectivity_state)gpr_atm_no_barrier_load(
           &tracker->current_state_atm);
   grpc_connectivity_state_watcher *w;
-  if (GRPC_TRACER_ON(grpc_connectivity_state_trace)) {
+  if (grpc_connectivity_state_trace.enabled()) {
     const char *error_string = grpc_error_string(error);
     gpr_log(GPR_DEBUG, "SET: %p %s: %s --> %s [%s] error=%p %s", tracker,
             tracker->name, grpc_connectivity_state_name(cur),
@@ -195,7 +194,7 @@ void grpc_connectivity_state_set(grpc_exec_ctx *exec_ctx,
   while ((w = tracker->watchers) != NULL) {
     *w->current = state;
     tracker->watchers = w->next;
-    if (GRPC_TRACER_ON(grpc_connectivity_state_trace)) {
+    if (grpc_connectivity_state_trace.enabled()) {
       gpr_log(GPR_DEBUG, "NOTIFY: %p %s: %p", tracker, tracker->name,
               w->notify);
     }

src/core/lib/transport/connectivity_state.h

@@ -47,7 +47,7 @@ typedef struct {
   char *name;
 } grpc_connectivity_state_tracker;
 
-extern grpc_tracer_flag grpc_connectivity_state_trace;
+extern grpc_core::TraceFlag grpc_connectivity_state_trace;
 
 /** enum --> string conversion */
 const char *grpc_connectivity_state_name(grpc_connectivity_state state);