Merge branch 'master' into gpr_review_host_port

43 files changed, 370 insertions, 560 deletions

diff --git a/src/core/ext/filters/client_channel/client_channel.cc b/src/core/ext/filters/client_channel/client_channel.cc
index a8a7a37be0..49522ef3e4 100644
--- a/src/core/ext/filters/client_channel/client_channel.cc
+++ b/src/core/ext/filters/client_channel/client_channel.cc
@@ -1333,12 +1333,12 @@ static void on_complete(void* arg, grpc_error* error) {
 
 static void cc_start_transport_stream_op_batch(
     grpc_call_element* elem, grpc_transport_stream_op_batch* batch) {
+  GPR_TIMER_SCOPE("cc_start_transport_stream_op_batch", 0);
   call_data* calld = (call_data*)elem->call_data;
   channel_data* chand = (channel_data*)elem->channel_data;
   if (chand->deadline_checking_enabled) {
     grpc_deadline_state_client_start_transport_stream_op_batch(elem, 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_client_channel_trace.enabled()) {
@@ -1347,7 +1347,7 @@ static void cc_start_transport_stream_op_batch(
     }
     grpc_transport_stream_op_batch_finish_with_failure(
         batch, GRPC_ERROR_REF(calld->error), calld->call_combiner);
-    goto done;
+    return;
   }
   if (batch->cancel_stream) {
     // Stash a copy of cancel_error in our call data, so that we can use
@@ -1369,7 +1369,7 @@ static void cc_start_transport_stream_op_batch(
       waiting_for_pick_batches_add(calld, batch);
       waiting_for_pick_batches_fail(elem, GRPC_ERROR_REF(calld->error));
     }
-    goto done;
+    return;
   }
   // Intercept on_complete for recv_trailing_metadata so that we can
   // check retry throttle status.
@@ -1391,7 +1391,7 @@ static void cc_start_transport_stream_op_batch(
               calld, calld->subchannel_call);
     }
     grpc_subchannel_call_process_op(calld->subchannel_call, batch);
-    goto done;
+    return;
   }
   // We do not yet have a subchannel call.
   // Add the batch to the waiting-for-pick list.
@@ -1417,8 +1417,6 @@ static void cc_start_transport_stream_op_batch(
     GRPC_CALL_COMBINER_STOP(calld->call_combiner,
                             "batch does not include send_initial_metadata");
   }
-done:
-  GPR_TIMER_END("cc_start_transport_stream_op_batch", 0);
 }
 
 /* Constructor for call_data */
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.cc
index 4596f90745..d6b759227e 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.cc
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.cc
@@ -98,7 +98,7 @@ static void destroy_call_elem(grpc_call_element* elem,
 static void start_transport_stream_op_batch(
     grpc_call_element* elem, grpc_transport_stream_op_batch* batch) {
   call_data* calld = (call_data*)elem->call_data;
-  GPR_TIMER_BEGIN("clr_start_transport_stream_op_batch", 0);
+  GPR_TIMER_SCOPE("clr_start_transport_stream_op_batch", 0);
   if (calld->client_stats != nullptr) {
     // Intercept send_initial_metadata.
     if (batch->send_initial_metadata) {
@@ -120,7 +120,6 @@ static void start_transport_stream_op_batch(
   }
   // Chain to next filter.
   grpc_call_next_op(elem, batch);
-  GPR_TIMER_END("clr_start_transport_stream_op_batch", 0);
 }
 
 const grpc_channel_filter grpc_client_load_reporting_filter = {
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc
index 3ade00550b..f2f25bc7c0 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc
@@ -66,8 +66,8 @@ typedef struct {
   grpc_pollset_set* interested_parties;
 
   /** Closures used by the combiner */
-  grpc_closure dns_ares_on_retry_timer_locked;
-  grpc_closure dns_ares_on_resolved_locked;
+  grpc_closure dns_ares_on_next_resolution_timer_closure;
+  grpc_closure dns_ares_on_resolved_closure;
 
   /** Combiner guarding the rest of the state */
   grpc_combiner* combiner;
@@ -85,12 +85,15 @@ typedef struct {
   grpc_channel_args** target_result;
   /** current (fully resolved) result */
   grpc_channel_args* resolved_result;
-  /** retry timer */
-  bool have_retry_timer;
-  grpc_timer retry_timer;
+  /** next resolution timer */
+  bool have_next_resolution_timer;
+  grpc_timer next_resolution_timer;
   /** retry backoff state */
   grpc_core::ManualConstructor<grpc_core::BackOff> backoff;
-
+  /** min resolution period. Max one resolution will happen per period */
+  grpc_millis min_time_between_resolutions;
+  /** when was the last resolution? -1 if no resolution has happened yet */
+  grpc_millis last_resolution_timestamp;
   /** currently resolving addresses */
   grpc_lb_addresses* lb_addresses;
   /** currently resolving service config */
@@ -100,6 +103,7 @@ typedef struct {
 static void dns_ares_destroy(grpc_resolver* r);
 
 static void dns_ares_start_resolving_locked(ares_dns_resolver* r);
+static void dns_ares_maybe_start_resolving_locked(ares_dns_resolver* r);
 static void dns_ares_maybe_finish_next_locked(ares_dns_resolver* r);
 
 static void dns_ares_shutdown_locked(grpc_resolver* r);
@@ -114,8 +118,8 @@ static const grpc_resolver_vtable dns_ares_resolver_vtable = {
 
 static void dns_ares_shutdown_locked(grpc_resolver* resolver) {
   ares_dns_resolver* r = (ares_dns_resolver*)resolver;
-  if (r->have_retry_timer) {
-    grpc_timer_cancel(&r->retry_timer);
+  if (r->have_next_resolution_timer) {
+    grpc_timer_cancel(&r->next_resolution_timer);
   }
   if (r->pending_request != nullptr) {
     grpc_cancel_ares_request(r->pending_request);
@@ -131,20 +135,20 @@ static void dns_ares_shutdown_locked(grpc_resolver* resolver) {
 static void dns_ares_channel_saw_error_locked(grpc_resolver* resolver) {
   ares_dns_resolver* r = (ares_dns_resolver*)resolver;
   if (!r->resolving) {
-    r->backoff->Reset();
-    dns_ares_start_resolving_locked(r);
+    dns_ares_maybe_start_resolving_locked(r);
   }
 }
 
-static void dns_ares_on_retry_timer_locked(void* arg, grpc_error* error) {
+static void dns_ares_on_next_resolution_timer_locked(void* arg,
+                                                     grpc_error* error) {
   ares_dns_resolver* r = (ares_dns_resolver*)arg;
-  r->have_retry_timer = false;
+  r->have_next_resolution_timer = false;
   if (error == GRPC_ERROR_NONE) {
     if (!r->resolving) {
       dns_ares_start_resolving_locked(r);
     }
   }
-  GRPC_RESOLVER_UNREF(&r->base, "retry-timer");
+  GRPC_RESOLVER_UNREF(&r->base, "next_resolution_timer");
 }
 
 static bool value_in_json_array(grpc_json* array, const char* value) {
@@ -261,6 +265,9 @@ static void dns_ares_on_resolved_locked(void* arg, grpc_error* error) {
     if (service_config != nullptr) grpc_service_config_destroy(service_config);
     gpr_free(service_config_string);
     grpc_lb_addresses_destroy(r->lb_addresses);
+    // Reset backoff state so that we start from the beginning when the
+    // next request gets triggered.
+    r->backoff->Reset();
   } else {
     const char* msg = grpc_error_string(error);
     gpr_log(GPR_DEBUG, "dns resolution failed: %s", msg);
@@ -268,21 +275,22 @@ static void dns_ares_on_resolved_locked(void* arg, grpc_error* error) {
     grpc_millis timeout = next_try - grpc_core::ExecCtx::Get()->Now();
     gpr_log(GPR_INFO, "dns resolution failed (will retry): %s",
             grpc_error_string(error));
-    GPR_ASSERT(!r->have_retry_timer);
-    r->have_retry_timer = true;
-    GRPC_RESOLVER_REF(&r->base, "retry-timer");
+    GPR_ASSERT(!r->have_next_resolution_timer);
+    r->have_next_resolution_timer = true;
+    GRPC_RESOLVER_REF(&r->base, "next_resolution_timer");
     if (timeout > 0) {
       gpr_log(GPR_DEBUG, "retrying in %" PRIdPTR " milliseconds", timeout);
     } else {
       gpr_log(GPR_DEBUG, "retrying immediately");
     }
-    grpc_timer_init(&r->retry_timer, next_try,
-                    &r->dns_ares_on_retry_timer_locked);
+    grpc_timer_init(&r->next_resolution_timer, next_try,
+                    &r->dns_ares_on_next_resolution_timer_closure);
   }
   if (r->resolved_result != nullptr) {
     grpc_channel_args_destroy(r->resolved_result);
   }
   r->resolved_result = result;
+  r->last_resolution_timestamp = grpc_core::ExecCtx::Get()->Now();
   r->resolved_version++;
   dns_ares_maybe_finish_next_locked(r);
   GRPC_RESOLVER_UNREF(&r->base, "dns-resolving");
@@ -297,8 +305,7 @@ static void dns_ares_next_locked(grpc_resolver* resolver,
   r->next_completion = on_complete;
   r->target_result = target_result;
   if (r->resolved_version == 0 && !r->resolving) {
-    r->backoff->Reset();
-    dns_ares_start_resolving_locked(r);
+    dns_ares_maybe_start_resolving_locked(r);
   } else {
     dns_ares_maybe_finish_next_locked(r);
   }
@@ -312,7 +319,7 @@ static void dns_ares_start_resolving_locked(ares_dns_resolver* r) {
   r->service_config_json = nullptr;
   r->pending_request = grpc_dns_lookup_ares(
       r->dns_server, r->name_to_resolve, r->default_port, r->interested_parties,
-      &r->dns_ares_on_resolved_locked, &r->lb_addresses,
+      &r->dns_ares_on_resolved_closure, &r->lb_addresses,
       true /* check_grpclb */,
       r->request_service_config ? &r->service_config_json : nullptr);
 }
@@ -330,6 +337,35 @@ static void dns_ares_maybe_finish_next_locked(ares_dns_resolver* r) {
   }
 }
 
+static void dns_ares_maybe_start_resolving_locked(ares_dns_resolver* r) {
+  if (r->last_resolution_timestamp >= 0) {
+    const grpc_millis earliest_next_resolution =
+        r->last_resolution_timestamp + r->min_time_between_resolutions;
+    const grpc_millis ms_until_next_resolution =
+        earliest_next_resolution - grpc_core::ExecCtx::Get()->Now();
+    if (ms_until_next_resolution > 0) {
+      const grpc_millis last_resolution_ago =
+          grpc_core::ExecCtx::Get()->Now() - r->last_resolution_timestamp;
+      gpr_log(GPR_DEBUG,
+              "In cooldown from last resolution (from %" PRIdPTR
+              " ms ago). Will resolve again in %" PRIdPTR " ms",
+              last_resolution_ago, ms_until_next_resolution);
+      if (!r->have_next_resolution_timer) {
+        r->have_next_resolution_timer = true;
+        GRPC_RESOLVER_REF(&r->base, "next_resolution_timer_cooldown");
+        grpc_timer_init(&r->next_resolution_timer, ms_until_next_resolution,
+                        &r->dns_ares_on_next_resolution_timer_closure);
+      }
+      // TODO(dgq): remove the following two lines once Pick First stops
+      // discarding subchannels after selecting.
+      ++r->resolved_version;
+      dns_ares_maybe_finish_next_locked(r);
+      return;
+    }
+  }
+  dns_ares_start_resolving_locked(r);
+}
+
 static void dns_ares_destroy(grpc_resolver* gr) {
   gpr_log(GPR_DEBUG, "dns_ares_destroy");
   ares_dns_resolver* r = (ares_dns_resolver*)gr;
@@ -374,12 +410,17 @@ static grpc_resolver* dns_ares_create(grpc_resolver_args* args,
       .set_jitter(GRPC_DNS_RECONNECT_JITTER)
       .set_max_backoff(GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
   r->backoff.Init(grpc_core::BackOff(backoff_options));
-  GRPC_CLOSURE_INIT(&r->dns_ares_on_retry_timer_locked,
-                    dns_ares_on_retry_timer_locked, r,
+  GRPC_CLOSURE_INIT(&r->dns_ares_on_next_resolution_timer_closure,
+                    dns_ares_on_next_resolution_timer_locked, r,
                     grpc_combiner_scheduler(r->base.combiner));
-  GRPC_CLOSURE_INIT(&r->dns_ares_on_resolved_locked,
+  GRPC_CLOSURE_INIT(&r->dns_ares_on_resolved_closure,
                     dns_ares_on_resolved_locked, r,
                     grpc_combiner_scheduler(r->base.combiner));
+  const grpc_arg* period_arg = grpc_channel_args_find(
+      args->args, GRPC_ARG_DNS_MIN_TIME_BETWEEN_RESOLUTIONS_MS);
+  r->min_time_between_resolutions =
+      grpc_channel_arg_get_integer(period_arg, {1000, 0, INT_MAX});
+  r->last_resolution_timestamp = -1;
   return &r->base;
 }
 
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc
index 03bd2acf6b..d76c8069d5 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc
@@ -505,7 +505,7 @@ static void on_dns_lookup_done_cb(void* arg, grpc_error* error) {
     }
   }
   GRPC_CLOSURE_SCHED(r->on_resolve_address_done, GRPC_ERROR_REF(error));
-  grpc_lb_addresses_destroy(r->lb_addrs);
+  if (r->lb_addrs != nullptr) grpc_lb_addresses_destroy(r->lb_addrs);
   gpr_free(r);
 }
 
diff --git a/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc b/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc
index 2f9a964628..478810d263 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc
+++ b/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc
@@ -19,10 +19,12 @@
 #include <grpc/support/port_platform.h>
 
 #include <inttypes.h>
-#include <string.h>
+#include <climits>
+#include <cstring>
 
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
+#include <grpc/support/time.h>
 
 #include "src/core/ext/filters/client_channel/lb_policy_registry.h"
 #include "src/core/ext/filters/client_channel/resolver_registry.h"
@@ -65,13 +67,16 @@ typedef struct {
   grpc_channel_args** target_result;
   /** current (fully resolved) result */
   grpc_channel_args* resolved_result;
-  /** retry timer */
-  bool have_retry_timer;
-  grpc_timer retry_timer;
-  grpc_closure on_retry;
+  /** next resolution timer */
+  bool have_next_resolution_timer;
+  grpc_timer next_resolution_timer;
+  grpc_closure next_resolution_closure;
   /** retry backoff state */
   grpc_core::ManualConstructor<grpc_core::BackOff> backoff;
-
+  /** min resolution period. Max one resolution will happen per period */
+  grpc_millis min_time_between_resolutions;
+  /** when was the last resolution? -1 if no resolution has happened yet */
+  grpc_millis last_resolution_timestamp;
   /** currently resolving addresses */
   grpc_resolved_addresses* addresses;
 } dns_resolver;
@@ -79,6 +84,7 @@ typedef struct {
 static void dns_destroy(grpc_resolver* r);
 
 static void dns_start_resolving_locked(dns_resolver* r);
+static void maybe_start_resolving_locked(dns_resolver* r);
 static void dns_maybe_finish_next_locked(dns_resolver* r);
 
 static void dns_shutdown_locked(grpc_resolver* r);
@@ -92,8 +98,8 @@ static const grpc_resolver_vtable dns_resolver_vtable = {
 
 static void dns_shutdown_locked(grpc_resolver* resolver) {
   dns_resolver* r = (dns_resolver*)resolver;
-  if (r->have_retry_timer) {
-    grpc_timer_cancel(&r->retry_timer);
+  if (r->have_next_resolution_timer) {
+    grpc_timer_cancel(&r->next_resolution_timer);
   }
   if (r->next_completion != nullptr) {
     *r->target_result = nullptr;
@@ -106,8 +112,7 @@ static void dns_shutdown_locked(grpc_resolver* resolver) {
 static void dns_channel_saw_error_locked(grpc_resolver* resolver) {
   dns_resolver* r = (dns_resolver*)resolver;
   if (!r->resolving) {
-    r->backoff->Reset();
-    dns_start_resolving_locked(r);
+    maybe_start_resolving_locked(r);
   }
 }
 
@@ -119,24 +124,19 @@ static void dns_next_locked(grpc_resolver* resolver,
   r->next_completion = on_complete;
   r->target_result = target_result;
   if (r->resolved_version == 0 && !r->resolving) {
-    r->backoff->Reset();
-    dns_start_resolving_locked(r);
+    maybe_start_resolving_locked(r);
   } else {
     dns_maybe_finish_next_locked(r);
   }
 }
 
-static void dns_on_retry_timer_locked(void* arg, grpc_error* error) {
+static void dns_on_next_resolution_timer_locked(void* arg, grpc_error* error) {
   dns_resolver* r = (dns_resolver*)arg;
-
-  r->have_retry_timer = false;
-  if (error == GRPC_ERROR_NONE) {
-    if (!r->resolving) {
-      dns_start_resolving_locked(r);
-    }
+  r->have_next_resolution_timer = false;
+  if (error == GRPC_ERROR_NONE && !r->resolving) {
+    dns_start_resolving_locked(r);
   }
-
-  GRPC_RESOLVER_UNREF(&r->base, "retry-timer");
+  GRPC_RESOLVER_UNREF(&r->base, "next_resolution_timer");
 }
 
 static void dns_on_resolved_locked(void* arg, grpc_error* error) {
@@ -160,22 +160,24 @@ static void dns_on_resolved_locked(void* arg, grpc_error* error) {
     result = grpc_channel_args_copy_and_add(r->channel_args, &new_arg, 1);
     grpc_resolved_addresses_destroy(r->addresses);
     grpc_lb_addresses_destroy(addresses);
+    // Reset backoff state so that we start from the beginning when the
+    // next request gets triggered.
+    r->backoff->Reset();
   } else {
     grpc_millis next_try = r->backoff->NextAttemptTime();
     grpc_millis timeout = next_try - grpc_core::ExecCtx::Get()->Now();
     gpr_log(GPR_INFO, "dns resolution failed (will retry): %s",
             grpc_error_string(error));
-    GPR_ASSERT(!r->have_retry_timer);
-    r->have_retry_timer = true;
-    GRPC_RESOLVER_REF(&r->base, "retry-timer");
+    GPR_ASSERT(!r->have_next_resolution_timer);
+    r->have_next_resolution_timer = true;
+    GRPC_RESOLVER_REF(&r->base, "next_resolution_timer");
     if (timeout > 0) {
       gpr_log(GPR_DEBUG, "retrying in %" PRIdPTR " milliseconds", timeout);
     } else {
       gpr_log(GPR_DEBUG, "retrying immediately");
     }
-    GRPC_CLOSURE_INIT(&r->on_retry, dns_on_retry_timer_locked, r,
-                      grpc_combiner_scheduler(r->base.combiner));
-    grpc_timer_init(&r->retry_timer, next_try, &r->on_retry);
+    grpc_timer_init(&r->next_resolution_timer, next_try,
+                    &r->next_resolution_closure);
   }
   if (r->resolved_result != nullptr) {
     grpc_channel_args_destroy(r->resolved_result);
@@ -188,6 +190,35 @@ static void dns_on_resolved_locked(void* arg, grpc_error* error) {
   GRPC_RESOLVER_UNREF(&r->base, "dns-resolving");
 }
 
+static void maybe_start_resolving_locked(dns_resolver* r) {
+  if (r->last_resolution_timestamp >= 0) {
+    const grpc_millis earliest_next_resolution =
+        r->last_resolution_timestamp + r->min_time_between_resolutions;
+    const grpc_millis ms_until_next_resolution =
+        earliest_next_resolution - grpc_core::ExecCtx::Get()->Now();
+    if (ms_until_next_resolution > 0) {
+      const grpc_millis last_resolution_ago =
+          grpc_core::ExecCtx::Get()->Now() - r->last_resolution_timestamp;
+      gpr_log(GPR_DEBUG,
+              "In cooldown from last resolution (from %" PRIdPTR
+              " ms ago). Will resolve again in %" PRIdPTR " ms",
+              last_resolution_ago, ms_until_next_resolution);
+      if (!r->have_next_resolution_timer) {
+        r->have_next_resolution_timer = true;
+        GRPC_RESOLVER_REF(&r->base, "next_resolution_timer_cooldown");
+        grpc_timer_init(&r->next_resolution_timer, ms_until_next_resolution,
+                        &r->next_resolution_closure);
+      }
+      // TODO(dgq): remove the following two lines once Pick First stops
+      // discarding subchannels after selecting.
+      ++r->resolved_version;
+      dns_maybe_finish_next_locked(r);
+      return;
+    }
+  }
+  dns_start_resolving_locked(r);
+}
+
 static void dns_start_resolving_locked(dns_resolver* r) {
   GRPC_RESOLVER_REF(&r->base, "dns-resolving");
   GPR_ASSERT(!r->resolving);
@@ -198,6 +229,7 @@ static void dns_start_resolving_locked(dns_resolver* r) {
       GRPC_CLOSURE_CREATE(dns_on_resolved_locked, r,
                           grpc_combiner_scheduler(r->base.combiner)),
       &r->addresses);
+  r->last_resolution_timestamp = grpc_core::ExecCtx::Get()->Now();
 }
 
 static void dns_maybe_finish_next_locked(dns_resolver* r) {
@@ -250,6 +282,14 @@ static grpc_resolver* dns_create(grpc_resolver_args* args,
       .set_jitter(GRPC_DNS_RECONNECT_JITTER)
       .set_max_backoff(GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
   r->backoff.Init(grpc_core::BackOff(backoff_options));
+  const grpc_arg* period_arg = grpc_channel_args_find(
+      args->args, GRPC_ARG_DNS_MIN_TIME_BETWEEN_RESOLUTIONS_MS);
+  r->min_time_between_resolutions =
+      grpc_channel_arg_get_integer(period_arg, {1000, 0, INT_MAX});
+  r->last_resolution_timestamp = -1;
+  GRPC_CLOSURE_INIT(&r->next_resolution_closure,
+                    dns_on_next_resolution_timer_locked, r,
+                    grpc_combiner_scheduler(r->base.combiner));
   return &r->base;
 }
 
diff --git a/src/core/ext/filters/client_channel/subchannel.cc b/src/core/ext/filters/client_channel/subchannel.cc
index cad8578511..dc1beee165 100644
--- a/src/core/ext/filters/client_channel/subchannel.cc
+++ b/src/core/ext/filters/client_channel/subchannel.cc
@@ -653,14 +653,13 @@ static void on_subchannel_connected(void* arg, grpc_error* error) {
  */
 
 static void subchannel_call_destroy(void* call, grpc_error* error) {
+  GPR_TIMER_SCOPE("grpc_subchannel_call_unref.destroy", 0);
   grpc_subchannel_call* c = (grpc_subchannel_call*)call;
   GPR_ASSERT(c->schedule_closure_after_destroy != nullptr);
-  GPR_TIMER_BEGIN("grpc_subchannel_call_unref.destroy", 0);
   grpc_core::ConnectedSubchannel* connection = c->connection;
   grpc_call_stack_destroy(SUBCHANNEL_CALL_TO_CALL_STACK(c), nullptr,
                           c->schedule_closure_after_destroy);
   connection->Unref(DEBUG_LOCATION, "subchannel_call");
-  GPR_TIMER_END("grpc_subchannel_call_unref.destroy", 0);
 }
 
 void grpc_subchannel_call_set_cleanup_closure(grpc_subchannel_call* call,
@@ -682,12 +681,11 @@ void grpc_subchannel_call_unref(
 
 void grpc_subchannel_call_process_op(grpc_subchannel_call* call,
                                      grpc_transport_stream_op_batch* batch) {
-  GPR_TIMER_BEGIN("grpc_subchannel_call_process_op", 0);
+  GPR_TIMER_SCOPE("grpc_subchannel_call_process_op", 0);
   grpc_call_stack* call_stack = SUBCHANNEL_CALL_TO_CALL_STACK(call);
   grpc_call_element* top_elem = grpc_call_stack_element(call_stack, 0);
   GRPC_CALL_LOG_OP(GPR_INFO, top_elem, batch);
   top_elem->filter->start_transport_stream_op_batch(top_elem, batch);
-  GPR_TIMER_END("grpc_subchannel_call_process_op", 0);
 }
 
 grpc_core::RefCountedPtr<grpc_core::ConnectedSubchannel>
diff --git a/src/core/ext/filters/http/client/http_client_filter.cc b/src/core/ext/filters/http/client/http_client_filter.cc
index 5584d50018..befd5a3c28 100644
--- a/src/core/ext/filters/http/client/http_client_filter.cc
+++ b/src/core/ext/filters/http/client/http_client_filter.cc
@@ -289,7 +289,7 @@ static void hc_start_transport_stream_op_batch(
     grpc_call_element* elem, grpc_transport_stream_op_batch* batch) {
   call_data* calld = (call_data*)elem->call_data;
   channel_data* channeld = (channel_data*)elem->channel_data;
-  GPR_TIMER_BEGIN("hc_start_transport_stream_op_batch", 0);
+  GPR_TIMER_SCOPE("hc_start_transport_stream_op_batch", 0);
 
   if (batch->recv_initial_metadata) {
     /* substitute our callback for the higher callback */
@@ -404,7 +404,6 @@ done:
   } else if (!batch_will_be_handled_asynchronously) {
     grpc_call_next_op(elem, batch);
   }
-  GPR_TIMER_END("hc_start_transport_stream_op_batch", 0);
 }
 
 /* Constructor for call_data */
diff --git a/src/core/ext/filters/http/message_compress/message_compress_filter.cc b/src/core/ext/filters/http/message_compress/message_compress_filter.cc
index 0218ec6e40..408301467c 100644
--- a/src/core/ext/filters/http/message_compress/message_compress_filter.cc
+++ b/src/core/ext/filters/http/message_compress/message_compress_filter.cc
@@ -347,8 +347,8 @@ static void start_send_message_batch(void* arg, grpc_error* unused) {
 
 static void compress_start_transport_stream_op_batch(
     grpc_call_element* elem, grpc_transport_stream_op_batch* batch) {
+  GPR_TIMER_SCOPE("compress_start_transport_stream_op_batch", 0);
   call_data* calld = (call_data*)elem->call_data;
-  GPR_TIMER_BEGIN("compress_start_transport_stream_op_batch", 0);
   // Handle cancel_stream.
   if (batch->cancel_stream) {
     GRPC_ERROR_UNREF(calld->cancel_error);
@@ -371,7 +371,7 @@ static void compress_start_transport_stream_op_batch(
   } else if (calld->cancel_error != GRPC_ERROR_NONE) {
     grpc_transport_stream_op_batch_finish_with_failure(
         batch, GRPC_ERROR_REF(calld->cancel_error), calld->call_combiner);
-    goto done;
+    return;
   }
   // Handle send_initial_metadata.
   if (batch->send_initial_metadata) {
@@ -383,7 +383,7 @@ static void compress_start_transport_stream_op_batch(
     if (error != GRPC_ERROR_NONE) {
       grpc_transport_stream_op_batch_finish_with_failure(batch, error,
                                                          calld->call_combiner);
-      goto done;
+      return;
     }
     calld->send_initial_metadata_state = has_compression_algorithm
                                              ? HAS_COMPRESSION_ALGORITHM
@@ -412,15 +412,13 @@ static void compress_start_transport_stream_op_batch(
       GRPC_CALL_COMBINER_STOP(
           calld->call_combiner,
           "send_message batch pending send_initial_metadata");
-      goto done;
+      return;
     }
     start_send_message_batch(elem, GRPC_ERROR_NONE);
   } else {
     // Pass control down the stack.
     grpc_call_next_op(elem, batch);
   }
-done:
-  GPR_TIMER_END("compress_start_transport_stream_op_batch", 0);
 }
 
 /* Constructor for call_data */
diff --git a/src/core/ext/filters/http/server/http_server_filter.cc b/src/core/ext/filters/http/server/http_server_filter.cc
index 508a3bf9fc..6ea942f053 100644
--- a/src/core/ext/filters/http/server/http_server_filter.cc
+++ b/src/core/ext/filters/http/server/http_server_filter.cc
@@ -367,8 +367,8 @@ static grpc_error* hs_mutate_op(grpc_call_element* elem,
 
 static void hs_start_transport_stream_op_batch(
     grpc_call_element* elem, grpc_transport_stream_op_batch* op) {
+  GPR_TIMER_SCOPE("hs_start_transport_stream_op_batch", 0);
   call_data* calld = (call_data*)elem->call_data;
-  GPR_TIMER_BEGIN("hs_start_transport_stream_op_batch", 0);
   grpc_error* error = hs_mutate_op(elem, op);
   if (error != GRPC_ERROR_NONE) {
     grpc_transport_stream_op_batch_finish_with_failure(op, error,
@@ -376,7 +376,6 @@ static void hs_start_transport_stream_op_batch(
   } else {
     grpc_call_next_op(elem, op);
   }
-  GPR_TIMER_END("hs_start_transport_stream_op_batch", 0);
 }
 
 /* Constructor for call_data */
diff --git a/src/core/ext/filters/load_reporting/server_load_reporting_filter.cc b/src/core/ext/filters/load_reporting/server_load_reporting_filter.cc
index a414229768..4c87d9755e 100644
--- a/src/core/ext/filters/load_reporting/server_load_reporting_filter.cc
+++ b/src/core/ext/filters/load_reporting/server_load_reporting_filter.cc
@@ -184,7 +184,7 @@ static grpc_filtered_mdelem lr_trailing_md_filter(void* user_data,
 
 static void lr_start_transport_stream_op_batch(
     grpc_call_element* elem, grpc_transport_stream_op_batch* op) {
-  GPR_TIMER_BEGIN("lr_start_transport_stream_op_batch", 0);
+  GPR_TIMER_SCOPE("lr_start_transport_stream_op_batch", 0);
   call_data* calld = (call_data*)elem->call_data;
 
   if (op->recv_initial_metadata) {
@@ -204,8 +204,6 @@ static void lr_start_transport_stream_op_batch(
             "LR trailing metadata filtering error"));
   }
   grpc_call_next_op(elem, op);
-
-  GPR_TIMER_END("lr_start_transport_stream_op_batch", 0);
 }
 
 const grpc_channel_filter grpc_server_load_reporting_filter = {
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.cc b/src/core/ext/transport/chttp2/transport/chttp2_transport.cc
index 530ab17bc7..fe05e43960 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.cc
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.cc
@@ -656,7 +656,7 @@ void grpc_chttp2_stream_unref(grpc_chttp2_stream* s) {
 static int init_stream(grpc_transport* gt, grpc_stream* gs,
                        grpc_stream_refcount* refcount, const void* server_data,
                        gpr_arena* arena) {
-  GPR_TIMER_BEGIN("init_stream", 0);
+  GPR_TIMER_SCOPE("init_stream", 0);
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)gt;
   grpc_chttp2_stream* s = (grpc_chttp2_stream*)gs;
 
@@ -700,17 +700,15 @@ static int init_stream(grpc_transport* gt, grpc_stream* gs,
   } else {
     s->flow_control.Init<grpc_core::chttp2::StreamFlowControlDisabled>();
   }
-  GPR_TIMER_END("init_stream", 0);
 
   return 0;
 }
 
 static void destroy_stream_locked(void* sp, grpc_error* error) {
+  GPR_TIMER_SCOPE("destroy_stream", 0);
   grpc_chttp2_stream* s = (grpc_chttp2_stream*)sp;
   grpc_chttp2_transport* t = s->t;
 
-  GPR_TIMER_BEGIN("destroy_stream", 0);
-
   GPR_ASSERT((s->write_closed && s->read_closed) || s->id == 0);
   if (s->id != 0) {
     GPR_ASSERT(grpc_chttp2_stream_map_find(&t->stream_map, s->id) == nullptr);
@@ -750,14 +748,12 @@ static void destroy_stream_locked(void* sp, grpc_error* error) {
 
   GRPC_CHTTP2_UNREF_TRANSPORT(t, "stream");
 
-  GPR_TIMER_END("destroy_stream", 0);
-
   GRPC_CLOSURE_SCHED(s->destroy_stream_arg, GRPC_ERROR_NONE);
 }
 
 static void destroy_stream(grpc_transport* gt, grpc_stream* gs,
                            grpc_closure* then_schedule_closure) {
-  GPR_TIMER_BEGIN("destroy_stream", 0);
+  GPR_TIMER_SCOPE("destroy_stream", 0);
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)gt;
   grpc_chttp2_stream* s = (grpc_chttp2_stream*)gs;
 
@@ -775,7 +771,6 @@ static void destroy_stream(grpc_transport* gt, grpc_stream* gs,
       GRPC_CLOSURE_INIT(&s->destroy_stream, destroy_stream_locked, s,
                         grpc_combiner_scheduler(t->combiner)),
       GRPC_ERROR_NONE);
-  GPR_TIMER_END("destroy_stream", 0);
 }
 
 grpc_chttp2_stream* grpc_chttp2_parsing_lookup_stream(grpc_chttp2_transport* t,
@@ -898,7 +893,7 @@ static void inc_initiate_write_reason(
 
 void grpc_chttp2_initiate_write(grpc_chttp2_transport* t,
                                 grpc_chttp2_initiate_write_reason reason) {
-  GPR_TIMER_BEGIN("grpc_chttp2_initiate_write", 0);
+  GPR_TIMER_SCOPE("grpc_chttp2_initiate_write", 0);
 
   switch (t->write_state) {
     case GRPC_CHTTP2_WRITE_STATE_IDLE:
@@ -920,7 +915,6 @@ void grpc_chttp2_initiate_write(grpc_chttp2_transport* t,
     case GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE:
       break;
   }
-  GPR_TIMER_END("grpc_chttp2_initiate_write", 0);
 }
 
 void grpc_chttp2_mark_stream_writable(grpc_chttp2_transport* t,
@@ -974,7 +968,7 @@ static const char* begin_writing_desc(bool partial, bool inlined) {
 }
 
 static void write_action_begin_locked(void* gt, grpc_error* error_ignored) {
-  GPR_TIMER_BEGIN("write_action_begin_locked", 0);
+  GPR_TIMER_SCOPE("write_action_begin_locked", 0);
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)gt;
   GPR_ASSERT(t->write_state != GRPC_CHTTP2_WRITE_STATE_IDLE);
   grpc_chttp2_begin_write_result r;
@@ -1008,21 +1002,19 @@ static void write_action_begin_locked(void* gt, grpc_error* error_ignored) {
     set_write_state(t, GRPC_CHTTP2_WRITE_STATE_IDLE, "begin writing nothing");
     GRPC_CHTTP2_UNREF_TRANSPORT(t, "writing");
   }
-  GPR_TIMER_END("write_action_begin_locked", 0);
 }
 
 static void write_action(void* gt, grpc_error* error) {
+  GPR_TIMER_SCOPE("write_action", 0);
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)gt;
-  GPR_TIMER_BEGIN("write_action", 0);
   grpc_endpoint_write(
       t->ep, &t->outbuf,
       GRPC_CLOSURE_INIT(&t->write_action_end_locked, write_action_end_locked, t,
                         grpc_combiner_scheduler(t->combiner)));
-  GPR_TIMER_END("write_action", 0);
 }
 
 static void write_action_end_locked(void* tp, grpc_error* error) {
-  GPR_TIMER_BEGIN("terminate_writing_with_lock", 0);
+  GPR_TIMER_SCOPE("terminate_writing_with_lock", 0);
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)tp;
 
   if (error != GRPC_ERROR_NONE) {
@@ -1060,7 +1052,6 @@ static void write_action_end_locked(void* tp, grpc_error* error) {
   grpc_chttp2_end_write(t, GRPC_ERROR_REF(error));
 
   GRPC_CHTTP2_UNREF_TRANSPORT(t, "writing");
-  GPR_TIMER_END("terminate_writing_with_lock", 0);
 }
 
 // Dirties an HTTP2 setting to be sent out next time a writing path occurs.
@@ -1335,7 +1326,7 @@ static void log_metadata(const grpc_metadata_batch* md_batch, uint32_t id,
 
 static void perform_stream_op_locked(void* stream_op,
                                      grpc_error* error_ignored) {
-  GPR_TIMER_BEGIN("perform_stream_op_locked", 0);
+  GPR_TIMER_SCOPE("perform_stream_op_locked", 0);
 
   grpc_transport_stream_op_batch* op =
       (grpc_transport_stream_op_batch*)stream_op;
@@ -1609,13 +1600,12 @@ static void perform_stream_op_locked(void* stream_op,
   grpc_chttp2_complete_closure_step(t, s, &on_complete, GRPC_ERROR_NONE,
                                     "op->on_complete");
 
-  GPR_TIMER_END("perform_stream_op_locked", 0);
   GRPC_CHTTP2_STREAM_UNREF(s, "perform_stream_op");
 }
 
 static void perform_stream_op(grpc_transport* gt, grpc_stream* gs,
                               grpc_transport_stream_op_batch* op) {
-  GPR_TIMER_BEGIN("perform_stream_op", 0);
+  GPR_TIMER_SCOPE("perform_stream_op", 0);
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)gt;
   grpc_chttp2_stream* s = (grpc_chttp2_stream*)gs;
 
@@ -1644,7 +1634,6 @@ static void perform_stream_op(grpc_transport* gt, grpc_stream* gs,
       GRPC_CLOSURE_INIT(&op->handler_private.closure, perform_stream_op_locked,
                         op, grpc_combiner_scheduler(t->combiner)),
       GRPC_ERROR_NONE);
-  GPR_TIMER_END("perform_stream_op", 0);
 }
 
 static void cancel_pings(grpc_chttp2_transport* t, grpc_error* error) {
@@ -2398,7 +2387,7 @@ static grpc_error* try_http_parsing(grpc_chttp2_transport* t) {
 }
 
 static void read_action_locked(void* tp, grpc_error* error) {
-  GPR_TIMER_BEGIN("reading_action_locked", 0);
+  GPR_TIMER_SCOPE("reading_action_locked", 0);
 
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)tp;
 
@@ -2414,7 +2403,7 @@ static void read_action_locked(void* tp, grpc_error* error) {
   GPR_SWAP(grpc_error*, err, error);
   GRPC_ERROR_UNREF(err);
   if (t->closed_with_error == GRPC_ERROR_NONE) {
-    GPR_TIMER_BEGIN("reading_action.parse", 0);
+    GPR_TIMER_SCOPE("reading_action.parse", 0);
     size_t i = 0;
     grpc_error* errors[3] = {GRPC_ERROR_REF(error), GRPC_ERROR_NONE,
                              GRPC_ERROR_NONE};
@@ -2435,9 +2424,8 @@ static void read_action_locked(void* tp, grpc_error* error) {
     for (i = 0; i < GPR_ARRAY_SIZE(errors); i++) {
       GRPC_ERROR_UNREF(errors[i]);
     }
-    GPR_TIMER_END("reading_action.parse", 0);
 
-    GPR_TIMER_BEGIN("post_parse_locked", 0);
+    GPR_TIMER_SCOPE("post_parse_locked", 0);
     if (t->initial_window_update != 0) {
       if (t->initial_window_update > 0) {
         grpc_chttp2_stream* s;
@@ -2449,10 +2437,9 @@ static void read_action_locked(void* tp, grpc_error* error) {
       }
       t->initial_window_update = 0;
     }
-    GPR_TIMER_END("post_parse_locked", 0);
   }
 
-  GPR_TIMER_BEGIN("post_reading_action_locked", 0);
+  GPR_TIMER_SCOPE("post_reading_action_locked", 0);
   bool keep_reading = false;
   if (error == GRPC_ERROR_NONE && t->closed_with_error != GRPC_ERROR_NONE) {
     error = GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
@@ -2482,11 +2469,7 @@ static void read_action_locked(void* tp, grpc_error* error) {
     GRPC_CHTTP2_UNREF_TRANSPORT(t, "reading_action");
   }
 
-  GPR_TIMER_END("post_reading_action_locked", 0);
-
   GRPC_ERROR_UNREF(error);
-
-  GPR_TIMER_END("reading_action_locked", 0);
 }
 
 // t is reffed prior to calling the first time, and once the callback chain
@@ -2786,12 +2769,11 @@ static void incoming_byte_stream_next_locked(void* argp,
 static bool incoming_byte_stream_next(grpc_byte_stream* byte_stream,
                                       size_t max_size_hint,
                                       grpc_closure* on_complete) {
-  GPR_TIMER_BEGIN("incoming_byte_stream_next", 0);
+  GPR_TIMER_SCOPE("incoming_byte_stream_next", 0);
   grpc_chttp2_incoming_byte_stream* bs =
       (grpc_chttp2_incoming_byte_stream*)byte_stream;
   grpc_chttp2_stream* s = bs->stream;
   if (s->unprocessed_incoming_frames_buffer.length > 0) {
-    GPR_TIMER_END("incoming_byte_stream_next", 0);
     return true;
   } else {
     gpr_ref(&bs->refs);
@@ -2802,14 +2784,13 @@ static bool incoming_byte_stream_next(grpc_byte_stream* byte_stream,
                           incoming_byte_stream_next_locked, bs,
                           grpc_combiner_scheduler(bs->transport->combiner)),
         GRPC_ERROR_NONE);
-    GPR_TIMER_END("incoming_byte_stream_next", 0);
     return false;
   }
 }
 
 static grpc_error* incoming_byte_stream_pull(grpc_byte_stream* byte_stream,
                                              grpc_slice* slice) {
-  GPR_TIMER_BEGIN("incoming_byte_stream_pull", 0);
+  GPR_TIMER_SCOPE("incoming_byte_stream_pull", 0);
   grpc_chttp2_incoming_byte_stream* bs =
       (grpc_chttp2_incoming_byte_stream*)byte_stream;
   grpc_chttp2_stream* s = bs->stream;
@@ -2853,7 +2834,6 @@ static grpc_error* incoming_byte_stream_pull(grpc_byte_stream* byte_stream,
     GRPC_CLOSURE_SCHED(&s->reset_byte_stream, GRPC_ERROR_REF(error));
     return error;
   }
-  GPR_TIMER_END("incoming_byte_stream_pull", 0);
   return GRPC_ERROR_NONE;
 }
 
@@ -2861,7 +2841,7 @@ static void incoming_byte_stream_destroy_locked(void* byte_stream,
                                                 grpc_error* error_ignored);
 
 static void incoming_byte_stream_destroy(grpc_byte_stream* byte_stream) {
-  GPR_TIMER_BEGIN("incoming_byte_stream_destroy", 0);
+  GPR_TIMER_SCOPE("incoming_byte_stream_destroy", 0);
   grpc_chttp2_incoming_byte_stream* bs =
       (grpc_chttp2_incoming_byte_stream*)byte_stream;
   GRPC_CLOSURE_SCHED(
@@ -2869,7 +2849,6 @@ static void incoming_byte_stream_destroy(grpc_byte_stream* byte_stream) {
                         incoming_byte_stream_destroy_locked, bs,
                         grpc_combiner_scheduler(bs->transport->combiner)),
       GRPC_ERROR_NONE);
-  GPR_TIMER_END("incoming_byte_stream_destroy", 0);
 }
 
 static void incoming_byte_stream_publish_error(
diff --git a/src/core/ext/transport/chttp2/transport/hpack_parser.cc b/src/core/ext/transport/chttp2/transport/hpack_parser.cc
index ebee5913cb..8d1c57a9cb 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_parser.cc
+++ b/src/core/ext/transport/chttp2/transport/hpack_parser.cc
@@ -1618,19 +1618,17 @@ grpc_error* grpc_chttp2_header_parser_parse(void* hpack_parser,
                                             grpc_chttp2_transport* t,
                                             grpc_chttp2_stream* s,
                                             grpc_slice slice, int is_last) {
+  GPR_TIMER_SCOPE("grpc_chttp2_hpack_parser_parse", 0);
   grpc_chttp2_hpack_parser* parser = (grpc_chttp2_hpack_parser*)hpack_parser;
-  GPR_TIMER_BEGIN("grpc_chttp2_hpack_parser_parse", 0);
   if (s != nullptr) {
     s->stats.incoming.header_bytes += GRPC_SLICE_LENGTH(slice);
   }
   grpc_error* error = grpc_chttp2_hpack_parser_parse(parser, slice);
   if (error != GRPC_ERROR_NONE) {
-    GPR_TIMER_END("grpc_chttp2_hpack_parser_parse", 0);
     return error;
   }
   if (is_last) {
     if (parser->is_boundary && parser->state != parse_begin) {
-      GPR_TIMER_END("grpc_chttp2_hpack_parser_parse", 0);
       return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
           "end of header frame not aligned with a hpack record boundary");
     }
@@ -1639,7 +1637,6 @@ grpc_error* grpc_chttp2_header_parser_parse(void* hpack_parser,
     if (s != nullptr) {
       if (parser->is_boundary) {
         if (s->header_frames_received == GPR_ARRAY_SIZE(s->metadata_buffer)) {
-          GPR_TIMER_END("grpc_chttp2_hpack_parser_parse", 0);
           return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
               "Too many trailer frames");
         }
@@ -1674,6 +1671,5 @@ grpc_error* grpc_chttp2_header_parser_parse(void* hpack_parser,
     parser->is_eof = 0xde;
     parser->dynamic_table_update_allowed = 2;
   }
-  GPR_TIMER_END("grpc_chttp2_hpack_parser_parse", 0);
   return GRPC_ERROR_NONE;
 }
diff --git a/src/core/ext/transport/chttp2/transport/parsing.cc b/src/core/ext/transport/chttp2/transport/parsing.cc
index 59dc38ef98..fb6d30b62d 100644
--- a/src/core/ext/transport/chttp2/transport/parsing.cc
+++ b/src/core/ext/transport/chttp2/transport/parsing.cc
@@ -392,11 +392,10 @@ error_handler:
 static void free_timeout(void* p) { gpr_free(p); }
 
 static void on_initial_header(void* tp, grpc_mdelem md) {
+  GPR_TIMER_SCOPE("on_initial_header", 0);
+
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)tp;
   grpc_chttp2_stream* s = t->incoming_stream;
-
-  GPR_TIMER_BEGIN("on_initial_header", 0);
-
   GPR_ASSERT(s != nullptr);
 
   if (grpc_http_trace.enabled()) {
@@ -470,16 +469,13 @@ static void on_initial_header(void* tp, grpc_mdelem md) {
       }
     }
   }
-
-  GPR_TIMER_END("on_initial_header", 0);
 }
 
 static void on_trailing_header(void* tp, grpc_mdelem md) {
+  GPR_TIMER_SCOPE("on_trailing_header", 0);
+
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)tp;
   grpc_chttp2_stream* s = t->incoming_stream;
-
-  GPR_TIMER_BEGIN("on_trailing_header", 0);
-
   GPR_ASSERT(s != nullptr);
 
   if (grpc_http_trace.enabled()) {
@@ -526,8 +522,6 @@ static void on_trailing_header(void* tp, grpc_mdelem md) {
       GRPC_MDELEM_UNREF(md);
     }
   }
-
-  GPR_TIMER_END("on_trailing_header", 0);
 }
 
 static grpc_error* init_header_frame_parser(grpc_chttp2_transport* t,
diff --git a/src/core/ext/transport/chttp2/transport/writing.cc b/src/core/ext/transport/chttp2/transport/writing.cc
index 9a6f5e9bcf..95358ab525 100644
--- a/src/core/ext/transport/chttp2/transport/writing.cc
+++ b/src/core/ext/transport/chttp2/transport/writing.cc
@@ -180,7 +180,7 @@ class WriteContext {
  public:
   WriteContext(grpc_chttp2_transport* t) : t_(t) {
     GRPC_STATS_INC_HTTP2_WRITES_BEGUN();
-    GPR_TIMER_BEGIN("grpc_chttp2_begin_write", 0);
+    GPR_TIMER_SCOPE("grpc_chttp2_begin_write", 0);
   }
 
   // TODO(ctiller): make this the destructor
@@ -614,13 +614,11 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
 
   maybe_initiate_ping(t);
 
-  GPR_TIMER_END("grpc_chttp2_begin_write", 0);
-
   return ctx.Result();
 }
 
 void grpc_chttp2_end_write(grpc_chttp2_transport* t, grpc_error* error) {
-  GPR_TIMER_BEGIN("grpc_chttp2_end_write", 0);
+  GPR_TIMER_SCOPE("grpc_chttp2_end_write", 0);
   grpc_chttp2_stream* s;
 
   while (grpc_chttp2_list_pop_writing_stream(t, &s)) {
@@ -633,5 +631,4 @@ void grpc_chttp2_end_write(grpc_chttp2_transport* t, grpc_error* error) {
   }
   grpc_slice_buffer_reset_and_unref_internal(&t->outbuf);
   GRPC_ERROR_UNREF(error);
-  GPR_TIMER_END("grpc_chttp2_end_write", 0);
 }
diff --git a/src/core/lib/gpr/alloc.cc b/src/core/lib/gpr/alloc.cc
index 000b7dcb25..b1d1550630 100644
--- a/src/core/lib/gpr/alloc.cc
+++ b/src/core/lib/gpr/alloc.cc
@@ -50,43 +50,39 @@ void gpr_set_allocation_functions(gpr_allocation_functions functions) {
 }
 
 void* gpr_malloc(size_t size) {
+  GPR_TIMER_SCOPE("gpr_malloc", 0);
   void* p;
   if (size == 0) return nullptr;
-  GPR_TIMER_BEGIN("gpr_malloc", 0);
   p = g_alloc_functions.malloc_fn(size);
   if (!p) {
     abort();
   }
-  GPR_TIMER_END("gpr_malloc", 0);
   return p;
 }
 
 void* gpr_zalloc(size_t size) {
+  GPR_TIMER_SCOPE("gpr_zalloc", 0);
   void* p;
   if (size == 0) return nullptr;
-  GPR_TIMER_BEGIN("gpr_zalloc", 0);
   p = g_alloc_functions.zalloc_fn(size);
   if (!p) {
     abort();
   }
-  GPR_TIMER_END("gpr_zalloc", 0);
   return p;
 }
 
 void gpr_free(void* p) {
-  GPR_TIMER_BEGIN("gpr_free", 0);
+  GPR_TIMER_SCOPE("gpr_free", 0);
   g_alloc_functions.free_fn(p);
-  GPR_TIMER_END("gpr_free", 0);
 }
 
 void* gpr_realloc(void* p, size_t size) {
+  GPR_TIMER_SCOPE("gpr_realloc", 0);
   if ((size == 0) && (p == nullptr)) return nullptr;
-  GPR_TIMER_BEGIN("gpr_realloc", 0);
   p = g_alloc_functions.realloc_fn(p, size);
   if (!p) {
     abort();
   }
-  GPR_TIMER_END("gpr_realloc", 0);
   return p;
 }
 
diff --git a/src/core/lib/gpr/sync_posix.cc b/src/core/lib/gpr/sync_posix.cc
index c3f6b10463..f23a8b2486 100644
--- a/src/core/lib/gpr/sync_posix.cc
+++ b/src/core/lib/gpr/sync_posix.cc
@@ -43,23 +43,19 @@ void gpr_mu_lock(gpr_mu* mu) {
 #ifdef GPR_LOW_LEVEL_COUNTERS
   GPR_ATM_INC_COUNTER(gpr_mu_locks);
 #endif
-  GPR_TIMER_BEGIN("gpr_mu_lock", 0);
+  GPR_TIMER_SCOPE("gpr_mu_lock", 0);
   GPR_ASSERT(pthread_mutex_lock(mu) == 0);
-  GPR_TIMER_END("gpr_mu_lock", 0);
 }
 
 void gpr_mu_unlock(gpr_mu* mu) {
-  GPR_TIMER_BEGIN("gpr_mu_unlock", 0);
+  GPR_TIMER_SCOPE("gpr_mu_unlock", 0);
   GPR_ASSERT(pthread_mutex_unlock(mu) == 0);
-  GPR_TIMER_END("gpr_mu_unlock", 0);
 }
 
 int gpr_mu_trylock(gpr_mu* mu) {
-  int err;
-  GPR_TIMER_BEGIN("gpr_mu_trylock", 0);
-  err = pthread_mutex_trylock(mu);
+  GPR_TIMER_SCOPE("gpr_mu_trylock", 0);
+  int err = pthread_mutex_trylock(mu);
   GPR_ASSERT(err == 0 || err == EBUSY);
-  GPR_TIMER_END("gpr_mu_trylock", 0);
   return err == 0;
 }
 
diff --git a/src/core/lib/iomgr/call_combiner.cc b/src/core/lib/iomgr/call_combiner.cc
index a9f48fb3c2..0e4c9cb3b3 100644
--- a/src/core/lib/iomgr/call_combiner.cc
+++ b/src/core/lib/iomgr/call_combiner.cc
@@ -60,7 +60,7 @@ void grpc_call_combiner_start(grpc_call_combiner* call_combiner,
                               grpc_closure* closure,
                               grpc_error* error DEBUG_ARGS,
                               const char* reason) {
-  GPR_TIMER_BEGIN("call_combiner_start", 0);
+  GPR_TIMER_SCOPE("call_combiner_start", 0);
   if (grpc_call_combiner_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "==> grpc_call_combiner_start() [%p] closure=%p [" DEBUG_FMT_STR
@@ -92,12 +92,11 @@ void grpc_call_combiner_start(grpc_call_combiner* call_combiner,
     closure->error_data.error = error;
     gpr_mpscq_push(&call_combiner->queue, (gpr_mpscq_node*)closure);
   }
-  GPR_TIMER_END("call_combiner_start", 0);
 }
 
 void grpc_call_combiner_stop(grpc_call_combiner* call_combiner DEBUG_ARGS,
                              const char* reason) {
-  GPR_TIMER_BEGIN("call_combiner_stop", 0);
+  GPR_TIMER_SCOPE("call_combiner_stop", 0);
   if (grpc_call_combiner_trace.enabled()) {
     gpr_log(GPR_DEBUG,
             "==> grpc_call_combiner_stop() [%p] [" DEBUG_FMT_STR "%s]",
@@ -136,7 +135,6 @@ void grpc_call_combiner_stop(grpc_call_combiner* call_combiner DEBUG_ARGS,
   } else if (grpc_call_combiner_trace.enabled()) {
     gpr_log(GPR_DEBUG, "  queue empty");
   }
-  GPR_TIMER_END("call_combiner_stop", 0);
 }
 
 void grpc_call_combiner_set_notify_on_cancel(grpc_call_combiner* call_combiner,
diff --git a/src/core/lib/iomgr/closure.h b/src/core/lib/iomgr/closure.h
index 249fca6cd6..2bf2578c63 100644
--- a/src/core/lib/iomgr/closure.h
+++ b/src/core/lib/iomgr/closure.h
@@ -247,7 +247,7 @@ inline void grpc_closure_run(const char* file, int line, grpc_closure* c,
 #else
 inline void grpc_closure_run(grpc_closure* c, grpc_error* error) {
 #endif
-  GPR_TIMER_BEGIN("grpc_closure_run", 0);
+  GPR_TIMER_SCOPE("grpc_closure_run", 0);
   if (c != nullptr) {
 #ifndef NDEBUG
     c->file_initiated = file;
@@ -259,7 +259,6 @@ inline void grpc_closure_run(grpc_closure* c, grpc_error* error) {
   } else {
     GRPC_ERROR_UNREF(error);
   }
-  GPR_TIMER_END("grpc_closure_run", 0);
 }
 
 /** Run a closure directly. Caller ensures that no locks are being held above.
@@ -278,7 +277,7 @@ inline void grpc_closure_sched(const char* file, int line, grpc_closure* c,
 #else
 inline void grpc_closure_sched(grpc_closure* c, grpc_error* error) {
 #endif
-  GPR_TIMER_BEGIN("grpc_closure_sched", 0);
+  GPR_TIMER_SCOPE("grpc_closure_sched", 0);
   if (c != nullptr) {
 #ifndef NDEBUG
     if (c->scheduled) {
@@ -299,7 +298,6 @@ inline void grpc_closure_sched(grpc_closure* c, grpc_error* error) {
   } else {
     GRPC_ERROR_UNREF(error);
   }
-  GPR_TIMER_END("grpc_closure_sched", 0);
 }
 
 /** Schedule a closure to be run. Does not need to be run from a safe point. */
diff --git a/src/core/lib/iomgr/combiner.cc b/src/core/lib/iomgr/combiner.cc
index e4d7a6abd8..2965d807c1 100644
--- a/src/core/lib/iomgr/combiner.cc
+++ b/src/core/lib/iomgr/combiner.cc
@@ -153,8 +153,8 @@ static void push_first_on_exec_ctx(grpc_combiner* lock) {
                     offsetof(grpc_combiner, scheduler_name)))
 
 static void combiner_exec(grpc_closure* cl, grpc_error* error) {
+  GPR_TIMER_SCOPE("combiner.execute", 0);
   GRPC_STATS_INC_COMBINER_LOCKS_SCHEDULED_ITEMS();
-  GPR_TIMER_BEGIN("combiner.execute", 0);
   grpc_combiner* lock = COMBINER_FROM_CLOSURE_SCHEDULER(cl, scheduler);
   gpr_atm last = gpr_atm_full_fetch_add(&lock->state, STATE_ELEM_COUNT_LOW_BIT);
   GRPC_COMBINER_TRACE(gpr_log(GPR_DEBUG,
@@ -181,7 +181,6 @@ static void combiner_exec(grpc_closure* cl, grpc_error* error) {
   assert(cl->cb);
   cl->error_data.error = error;
   gpr_mpscq_push(&lock->queue, &cl->next_data.atm_next);
-  GPR_TIMER_END("combiner.execute", 0);
 }
 
 static void move_next() {
@@ -207,11 +206,10 @@ static void queue_offload(grpc_combiner* lock) {
 }
 
 bool grpc_combiner_continue_exec_ctx() {
-  GPR_TIMER_BEGIN("combiner.continue_exec_ctx", 0);
+  GPR_TIMER_SCOPE("combiner.continue_exec_ctx", 0);
   grpc_combiner* lock =
       grpc_core::ExecCtx::Get()->combiner_data()->active_combiner;
   if (lock == nullptr) {
-    GPR_TIMER_END("combiner.continue_exec_ctx", 0);
     return false;
   }
 
@@ -233,7 +231,6 @@ bool grpc_combiner_continue_exec_ctx() {
     // this execution context wants to move on: schedule remaining work to be
     // picked up on the executor
     queue_offload(lock);
-    GPR_TIMER_END("combiner.continue_exec_ctx", 0);
     return true;
   }
 
@@ -249,10 +246,9 @@ bool grpc_combiner_continue_exec_ctx() {
       // go off and do something else for a while (and come back later)
       GPR_TIMER_MARK("delay_busy", 0);
       queue_offload(lock);
-      GPR_TIMER_END("combiner.continue_exec_ctx", 0);
       return true;
     }
-    GPR_TIMER_BEGIN("combiner.exec1", 0);
+    GPR_TIMER_SCOPE("combiner.exec1", 0);
     grpc_closure* cl = (grpc_closure*)n;
     grpc_error* cl_err = cl->error_data.error;
 #ifndef NDEBUG
@@ -260,14 +256,13 @@ bool grpc_combiner_continue_exec_ctx() {
 #endif
     cl->cb(cl->cb_arg, cl_err);
     GRPC_ERROR_UNREF(cl_err);
-    GPR_TIMER_END("combiner.exec1", 0);
   } else {
     grpc_closure* c = lock->final_list.head;
     GPR_ASSERT(c != nullptr);
     grpc_closure_list_init(&lock->final_list);
     int loops = 0;
     while (c != nullptr) {
-      GPR_TIMER_BEGIN("combiner.exec_1final", 0);
+      GPR_TIMER_SCOPE("combiner.exec_1final", 0);
       GRPC_COMBINER_TRACE(
           gpr_log(GPR_DEBUG, "C:%p execute_final[%d] c=%p", lock, loops, c));
       grpc_closure* next = c->next_data.next;
@@ -278,7 +273,6 @@ bool grpc_combiner_continue_exec_ctx() {
       c->cb(c->cb_arg, error);
       GRPC_ERROR_UNREF(error);
       c = next;
-      GPR_TIMER_END("combiner.exec_1final", 0);
     }
   }
 
@@ -308,41 +302,36 @@ bool grpc_combiner_continue_exec_ctx() {
       break;
     case OLD_STATE_WAS(false, 1):
       // had one count, one unorphaned --> unlocked unorphaned
-      GPR_TIMER_END("combiner.continue_exec_ctx", 0);
       return true;
     case OLD_STATE_WAS(true, 1):
       // and one count, one orphaned --> unlocked and orphaned
       really_destroy(lock);
-      GPR_TIMER_END("combiner.continue_exec_ctx", 0);
       return true;
     case OLD_STATE_WAS(false, 0):
     case OLD_STATE_WAS(true, 0):
       // these values are illegal - representing an already unlocked or
       // deleted lock
-      GPR_TIMER_END("combiner.continue_exec_ctx", 0);
       GPR_UNREACHABLE_CODE(return true);
   }
   push_first_on_exec_ctx(lock);
-  GPR_TIMER_END("combiner.continue_exec_ctx", 0);
   return true;
 }
 
 static void enqueue_finally(void* closure, grpc_error* error);
 
 static void combiner_finally_exec(grpc_closure* closure, grpc_error* error) {
+  GPR_TIMER_SCOPE("combiner.execute_finally", 0);
   GRPC_STATS_INC_COMBINER_LOCKS_SCHEDULED_FINAL_ITEMS();
   grpc_combiner* lock =
       COMBINER_FROM_CLOSURE_SCHEDULER(closure, finally_scheduler);
   GRPC_COMBINER_TRACE(gpr_log(
       GPR_DEBUG, "C:%p grpc_combiner_execute_finally c=%p; ac=%p", lock,
       closure, grpc_core::ExecCtx::Get()->combiner_data()->active_combiner));
-  GPR_TIMER_BEGIN("combiner.execute_finally", 0);
   if (grpc_core::ExecCtx::Get()->combiner_data()->active_combiner != lock) {
     GPR_TIMER_MARK("slowpath", 0);
     GRPC_CLOSURE_SCHED(GRPC_CLOSURE_CREATE(enqueue_finally, closure,
                                            grpc_combiner_scheduler(lock)),
                        error);
-    GPR_TIMER_END("combiner.execute_finally", 0);
     return;
   }
 
@@ -350,7 +339,6 @@ static void combiner_finally_exec(grpc_closure* closure, grpc_error* error) {
     gpr_atm_full_fetch_add(&lock->state, STATE_ELEM_COUNT_LOW_BIT);
   }
   grpc_closure_list_append(&lock->final_list, closure, error);
-  GPR_TIMER_END("combiner.execute_finally", 0);
 }
 
 static void enqueue_finally(void* closure, grpc_error* error) {
diff --git a/src/core/lib/iomgr/error.cc b/src/core/lib/iomgr/error.cc
index 67c3caf5ee..0e27ad427c 100644
--- a/src/core/lib/iomgr/error.cc
+++ b/src/core/lib/iomgr/error.cc
@@ -314,7 +314,7 @@ static void internal_add_error(grpc_error** err, grpc_error* new_err) {
 grpc_error* grpc_error_create(const char* file, int line, grpc_slice desc,
                               grpc_error** referencing,
                               size_t num_referencing) {
-  GPR_TIMER_BEGIN("grpc_error_create", 0);
+  GPR_TIMER_SCOPE("grpc_error_create", 0);
   uint8_t initial_arena_capacity = (uint8_t)(
       DEFAULT_ERROR_CAPACITY +
       (uint8_t)(num_referencing * SLOTS_PER_LINKED_ERROR) + SURPLUS_CAPACITY);
@@ -355,7 +355,6 @@ grpc_error* grpc_error_create(const char* file, int line, grpc_slice desc,
 
   gpr_atm_no_barrier_store(&err->atomics.error_string, 0);
   gpr_ref_init(&err->atomics.refs, 1);
-  GPR_TIMER_END("grpc_error_create", 0);
   return err;
 }
 
@@ -378,7 +377,7 @@ static void ref_errs(grpc_error* err) {
 }
 
 static grpc_error* copy_error_and_unref(grpc_error* in) {
-  GPR_TIMER_BEGIN("copy_error_and_unref", 0);
+  GPR_TIMER_SCOPE("copy_error_and_unref", 0);
   grpc_error* out;
   if (grpc_error_is_special(in)) {
     out = GRPC_ERROR_CREATE_FROM_STATIC_STRING("unknown");
@@ -422,16 +421,14 @@ static grpc_error* copy_error_and_unref(grpc_error* in) {
     ref_errs(out);
     GRPC_ERROR_UNREF(in);
   }
-  GPR_TIMER_END("copy_error_and_unref", 0);
   return out;
 }
 
 grpc_error* grpc_error_set_int(grpc_error* src, grpc_error_ints which,
                                intptr_t value) {
-  GPR_TIMER_BEGIN("grpc_error_set_int", 0);
+  GPR_TIMER_SCOPE("grpc_error_set_int", 0);
   grpc_error* new_err = copy_error_and_unref(src);
   internal_set_int(&new_err, which, value);
-  GPR_TIMER_END("grpc_error_set_int", 0);
   return new_err;
 }
 
@@ -447,36 +444,31 @@ static special_error_status_map error_status_map[] = {
 };
 
 bool grpc_error_get_int(grpc_error* err, grpc_error_ints which, intptr_t* p) {
-  GPR_TIMER_BEGIN("grpc_error_get_int", 0);
+  GPR_TIMER_SCOPE("grpc_error_get_int", 0);
   if (grpc_error_is_special(err)) {
     if (which == GRPC_ERROR_INT_GRPC_STATUS) {
       for (size_t i = 0; i < GPR_ARRAY_SIZE(error_status_map); i++) {
         if (error_status_map[i].error == err) {
           if (p != nullptr) *p = error_status_map[i].code;
-          GPR_TIMER_END("grpc_error_get_int", 0);
           return true;
         }
       }
     }
-    GPR_TIMER_END("grpc_error_get_int", 0);
     return false;
   }
   uint8_t slot = err->ints[which];
   if (slot != UINT8_MAX) {
     if (p != nullptr) *p = err->arena[slot];
-    GPR_TIMER_END("grpc_error_get_int", 0);
     return true;
   }
-  GPR_TIMER_END("grpc_error_get_int", 0);
   return false;
 }
 
 grpc_error* grpc_error_set_str(grpc_error* src, grpc_error_strs which,
                                grpc_slice str) {
-  GPR_TIMER_BEGIN("grpc_error_set_str", 0);
+  GPR_TIMER_SCOPE("grpc_error_set_str", 0);
   grpc_error* new_err = copy_error_and_unref(src);
   internal_set_str(&new_err, which, str);
-  GPR_TIMER_END("grpc_error_set_str", 0);
   return new_err;
 }
 
@@ -503,10 +495,9 @@ bool grpc_error_get_str(grpc_error* err, grpc_error_strs which,
 }
 
 grpc_error* grpc_error_add_child(grpc_error* src, grpc_error* child) {
-  GPR_TIMER_BEGIN("grpc_error_add_child", 0);
+  GPR_TIMER_SCOPE("grpc_error_add_child", 0);
   grpc_error* new_err = copy_error_and_unref(src);
   internal_add_error(&new_err, child);
-  GPR_TIMER_END("grpc_error_add_child", 0);
   return new_err;
 }
 
@@ -722,14 +713,13 @@ static char* finish_kvs(kv_pairs* kvs) {
 }
 
 const char* grpc_error_string(grpc_error* err) {
-  GPR_TIMER_BEGIN("grpc_error_string", 0);
+  GPR_TIMER_SCOPE("grpc_error_string", 0);
   if (err == GRPC_ERROR_NONE) return no_error_string;
   if (err == GRPC_ERROR_OOM) return oom_error_string;
   if (err == GRPC_ERROR_CANCELLED) return cancelled_error_string;
 
   void* p = (void*)gpr_atm_acq_load(&err->atomics.error_string);
   if (p != nullptr) {
-    GPR_TIMER_END("grpc_error_string", 0);
     return (const char*)p;
   }
 
@@ -752,7 +742,6 @@ const char* grpc_error_string(grpc_error* err) {
     out = (char*)gpr_atm_acq_load(&err->atomics.error_string);
   }
 
-  GPR_TIMER_END("grpc_error_string", 0);
   return out;
 }
 
diff --git a/src/core/lib/iomgr/ev_epoll1_linux.cc b/src/core/lib/iomgr/ev_epoll1_linux.cc
index ad274b839c..1ef70d2f80 100644
--- a/src/core/lib/iomgr/ev_epoll1_linux.cc
+++ b/src/core/lib/iomgr/ev_epoll1_linux.cc
@@ -519,7 +519,7 @@ static void pollset_destroy(grpc_pollset* pollset) {
 }
 
 static grpc_error* pollset_kick_all(grpc_pollset* pollset) {
-  GPR_TIMER_BEGIN("pollset_kick_all", 0);
+  GPR_TIMER_SCOPE("pollset_kick_all", 0);
   grpc_error* error = GRPC_ERROR_NONE;
   if (pollset->root_worker != nullptr) {
     grpc_pollset_worker* worker = pollset->root_worker;
@@ -549,7 +549,6 @@ static grpc_error* pollset_kick_all(grpc_pollset* pollset) {
   }
   // TODO: sreek.  Check if we need to set 'kicked_without_poller' to true here
   // in the else case
-  GPR_TIMER_END("pollset_kick_all", 0);
   return error;
 }
 
@@ -563,14 +562,13 @@ static void pollset_maybe_finish_shutdown(grpc_pollset* pollset) {
 }
 
 static void pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure) {
-  GPR_TIMER_BEGIN("pollset_shutdown", 0);
+  GPR_TIMER_SCOPE("pollset_shutdown", 0);
   GPR_ASSERT(pollset->shutdown_closure == nullptr);
   GPR_ASSERT(!pollset->shutting_down);
   pollset->shutdown_closure = closure;
   pollset->shutting_down = true;
   GRPC_LOG_IF_ERROR("pollset_shutdown", pollset_kick_all(pollset));
   pollset_maybe_finish_shutdown(pollset);
-  GPR_TIMER_END("pollset_shutdown", 0);
 }
 
 static int poll_deadline_to_millis_timeout(grpc_millis millis) {
@@ -594,10 +592,10 @@ static int poll_deadline_to_millis_timeout(grpc_millis millis) {
    called by g_active_poller thread. So there is no need for synchronization
    when accessing fields in g_epoll_set */
 static grpc_error* process_epoll_events(grpc_pollset* pollset) {
+  GPR_TIMER_SCOPE("process_epoll_events", 0);
+
   static const char* err_desc = "process_events";
   grpc_error* error = GRPC_ERROR_NONE;
-
-  GPR_TIMER_BEGIN("process_epoll_events", 0);
   long num_events = gpr_atm_acq_load(&g_epoll_set.num_events);
   long cursor = gpr_atm_acq_load(&g_epoll_set.cursor);
   for (int idx = 0;
@@ -626,7 +624,6 @@ static grpc_error* process_epoll_events(grpc_pollset* pollset) {
     }
   }
   gpr_atm_rel_store(&g_epoll_set.cursor, cursor);
-  GPR_TIMER_END("process_epoll_events", 0);
   return error;
 }
 
@@ -638,7 +635,7 @@ static grpc_error* process_epoll_events(grpc_pollset* pollset) {
    (i.e the designated poller thread) will be calling this function. So there is
    no need for any synchronization when accesing fields in g_epoll_set */
 static grpc_error* do_epoll_wait(grpc_pollset* ps, grpc_millis deadline) {
-  GPR_TIMER_BEGIN("do_epoll_wait", 0);
+  GPR_TIMER_SCOPE("do_epoll_wait", 0);
 
   int r;
   int timeout = poll_deadline_to_millis_timeout(deadline);
@@ -665,14 +662,13 @@ static grpc_error* do_epoll_wait(grpc_pollset* ps, grpc_millis deadline) {
   gpr_atm_rel_store(&g_epoll_set.num_events, r);
   gpr_atm_rel_store(&g_epoll_set.cursor, 0);
 
-  GPR_TIMER_END("do_epoll_wait", 0);
   return GRPC_ERROR_NONE;
 }
 
 static bool begin_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
                          grpc_pollset_worker** worker_hdl,
                          grpc_millis deadline) {
-  GPR_TIMER_BEGIN("begin_worker", 0);
+  GPR_TIMER_SCOPE("begin_worker", 0);
   if (worker_hdl != nullptr) *worker_hdl = worker;
   worker->initialized_cv = false;
   SET_KICK_STATE(worker, UNKICKED);
@@ -786,17 +782,15 @@ static bool begin_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
 
   if (pollset->kicked_without_poller) {
     pollset->kicked_without_poller = false;
-    GPR_TIMER_END("begin_worker", 0);
     return false;
   }
 
-  GPR_TIMER_END("begin_worker", 0);
   return worker->state == DESIGNATED_POLLER && !pollset->shutting_down;
 }
 
 static bool check_neighborhood_for_available_poller(
     pollset_neighborhood* neighborhood) {
-  GPR_TIMER_BEGIN("check_neighborhood_for_available_poller", 0);
+  GPR_TIMER_SCOPE("check_neighborhood_for_available_poller", 0);
   bool found_worker = false;
   do {
     grpc_pollset* inspect = neighborhood->active_root;
@@ -855,13 +849,12 @@ static bool check_neighborhood_for_available_poller(
     }
     gpr_mu_unlock(&inspect->mu);
   } while (!found_worker);
-  GPR_TIMER_END("check_neighborhood_for_available_poller", 0);
   return found_worker;
 }
 
 static void end_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
                        grpc_pollset_worker** worker_hdl) {
-  GPR_TIMER_BEGIN("end_worker", 0);
+  GPR_TIMER_SCOPE("end_worker", 0);
   if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PS:%p END_WORKER:%p", pollset, worker);
   }
@@ -931,7 +924,6 @@ static void end_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
     pollset_maybe_finish_shutdown(pollset);
   }
   GPR_ASSERT(gpr_atm_no_barrier_load(&g_active_poller) != (gpr_atm)worker);
-  GPR_TIMER_END("end_worker", 0);
 }
 
 /* pollset->po.mu lock must be held by the caller before calling this.
@@ -941,13 +933,12 @@ static void end_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
 static grpc_error* pollset_work(grpc_pollset* ps,
                                 grpc_pollset_worker** worker_hdl,
                                 grpc_millis deadline) {
+  GPR_TIMER_SCOPE("pollset_work", 0);
   grpc_pollset_worker worker;
   grpc_error* error = GRPC_ERROR_NONE;
   static const char* err_desc = "pollset_work";
-  GPR_TIMER_BEGIN("pollset_work", 0);
   if (ps->kicked_without_poller) {
     ps->kicked_without_poller = false;
-    GPR_TIMER_END("pollset_work", 0);
     return GRPC_ERROR_NONE;
   }
 
@@ -987,13 +978,12 @@ static grpc_error* pollset_work(grpc_pollset* ps,
   end_worker(ps, &worker, worker_hdl);
 
   gpr_tls_set(&g_current_thread_pollset, 0);
-  GPR_TIMER_END("pollset_work", 0);
   return error;
 }
 
 static grpc_error* pollset_kick(grpc_pollset* pollset,
                                 grpc_pollset_worker* specific_worker) {
-  GPR_TIMER_BEGIN("pollset_kick", 0);
+  GPR_TIMER_SCOPE("pollset_kick", 0);
   GRPC_STATS_INC_POLLSET_KICK();
   grpc_error* ret_err = GRPC_ERROR_NONE;
   if (grpc_polling_trace.enabled()) {
@@ -1150,7 +1140,6 @@ static grpc_error* pollset_kick(grpc_pollset* pollset,
     goto done;
   }
 done:
-  GPR_TIMER_END("pollset_kick", 0);
   return ret_err;
 }
 
diff --git a/src/core/lib/iomgr/ev_epollex_linux.cc b/src/core/lib/iomgr/ev_epollex_linux.cc
index 416e8384b4..178ebd8977 100644
--- a/src/core/lib/iomgr/ev_epollex_linux.cc
+++ b/src/core/lib/iomgr/ev_epollex_linux.cc
@@ -199,6 +199,7 @@ struct grpc_pollset {
   pollable* active_pollable;
   bool kicked_without_poller;
   grpc_closure* shutdown_closure;
+  bool already_shutdown;
   grpc_pollset_worker* root_worker;
   int containing_pollset_set_count;
 };
@@ -560,8 +561,10 @@ static void pollset_maybe_finish_shutdown(grpc_pollset* pollset) {
   }
   if (pollset->shutdown_closure != nullptr && pollset->root_worker == nullptr &&
       pollset->containing_pollset_set_count == 0) {
+    GPR_TIMER_MARK("pollset_finish_shutdown", 0);
     GRPC_CLOSURE_SCHED(pollset->shutdown_closure, GRPC_ERROR_NONE);
     pollset->shutdown_closure = nullptr;
+    pollset->already_shutdown = true;
   }
 }
 
@@ -569,6 +572,7 @@ static void pollset_maybe_finish_shutdown(grpc_pollset* pollset) {
  * pollset->active_pollable->mu & specific_worker->pollable_obj->mu must not be
  * held */
 static grpc_error* kick_one_worker(grpc_pollset_worker* specific_worker) {
+  GPR_TIMER_SCOPE("kick_one_worker", 0);
   pollable* p = specific_worker->pollable_obj;
   grpc_core::mu_guard lock(&p->mu);
   GPR_ASSERT(specific_worker != nullptr);
@@ -612,6 +616,7 @@ static grpc_error* kick_one_worker(grpc_pollset_worker* specific_worker) {
 
 static grpc_error* pollset_kick(grpc_pollset* pollset,
                                 grpc_pollset_worker* specific_worker) {
+  GPR_TIMER_SCOPE("pollset_kick", 0);
   GRPC_STATS_INC_POLLSET_KICK();
   if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG,
@@ -661,6 +666,7 @@ static grpc_error* pollset_kick(grpc_pollset* pollset,
 }
 
 static grpc_error* pollset_kick_all(grpc_pollset* pollset) {
+  GPR_TIMER_SCOPE("pollset_kick_all", 0);
   grpc_error* error = GRPC_ERROR_NONE;
   const char* err_desc = "pollset_kick_all";
   grpc_pollset_worker* w = pollset->root_worker;
@@ -677,6 +683,11 @@ static grpc_error* pollset_kick_all(grpc_pollset* pollset) {
 static void pollset_init(grpc_pollset* pollset, gpr_mu** mu) {
   gpr_mu_init(&pollset->mu);
   pollset->active_pollable = POLLABLE_REF(g_empty_pollable, "pollset");
+  pollset->kicked_without_poller = false;
+  pollset->shutdown_closure = nullptr;
+  pollset->already_shutdown = false;
+  pollset->root_worker = nullptr;
+  pollset->containing_pollset_set_count = 0;
   *mu = &pollset->mu;
 }
 
@@ -733,6 +744,7 @@ static grpc_error* fd_get_or_become_pollable(grpc_fd* fd, pollable** p) {
 
 /* pollset->po.mu lock must be held by the caller before calling this */
 static void pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure) {
+  GPR_TIMER_SCOPE("pollset_shutdown", 0);
   GPR_ASSERT(pollset->shutdown_closure == nullptr);
   pollset->shutdown_closure = closure;
   GRPC_LOG_IF_ERROR("pollset_shutdown", pollset_kick_all(pollset));
@@ -741,6 +753,7 @@ static void pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure) {
 
 static grpc_error* pollable_process_events(grpc_pollset* pollset,
                                            pollable* pollable_obj, bool drain) {
+  GPR_TIMER_SCOPE("pollable_process_events", 0);
   static const char* err_desc = "pollset_process_events";
   grpc_error* error = GRPC_ERROR_NONE;
   for (int i = 0; (drain || i < MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL) &&
@@ -787,6 +800,7 @@ static void pollset_destroy(grpc_pollset* pollset) {
 }
 
 static grpc_error* pollable_epoll(pollable* p, grpc_millis deadline) {
+  GPR_TIMER_SCOPE("pollable_epoll", 0);
   int timeout = poll_deadline_to_millis_timeout(deadline);
 
   if (grpc_polling_trace.enabled()) {
@@ -862,7 +876,9 @@ static worker_remove_result worker_remove(grpc_pollset_worker** root_worker,
 static bool begin_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
                          grpc_pollset_worker** worker_hdl,
                          grpc_millis deadline) {
-  bool do_poll = (pollset->shutdown_closure == nullptr);
+  GPR_TIMER_SCOPE("begin_worker", 0);
+  bool do_poll =
+      (pollset->shutdown_closure == nullptr && !pollset->already_shutdown);
   if (worker_hdl != nullptr) *worker_hdl = worker;
   worker->initialized_cv = false;
   worker->kicked = false;
@@ -913,6 +929,7 @@ static bool begin_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
 
 static void end_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
                        grpc_pollset_worker** worker_hdl) {
+  GPR_TIMER_SCOPE("end_worker", 0);
   gpr_mu_lock(&pollset->mu);
   gpr_mu_lock(&worker->pollable_obj->mu);
   switch (worker_remove(&worker->pollable_obj->root_worker, worker,
@@ -955,6 +972,7 @@ static long gettid(void) { return syscall(__NR_gettid); }
 static grpc_error* pollset_work(grpc_pollset* pollset,
                                 grpc_pollset_worker** worker_hdl,
                                 grpc_millis deadline) {
+  GPR_TIMER_SCOPE("pollset_work", 0);
 #ifdef GRPC_EPOLLEX_CREATE_WORKERS_ON_HEAP
   grpc_pollset_worker* worker =
       (grpc_pollset_worker*)gpr_malloc(sizeof(*worker));
@@ -1092,6 +1110,16 @@ static grpc_error* pollset_as_multipollable_locked(grpc_pollset* pollset,
     case PO_EMPTY:
       POLLABLE_UNREF(pollset->active_pollable, "pollset");
       error = pollable_create(PO_MULTI, &pollset->active_pollable);
+      /* Any workers currently polling on this pollset must now be woked up so
+       * that they can pick up the new active_pollable */
+      if (grpc_polling_trace.enabled()) {
+        gpr_log(GPR_DEBUG,
+                "PS:%p active pollable transition from empty to multi",
+                pollset);
+      }
+      static const char* err_desc =
+          "pollset_as_multipollable_locked: empty -> multi";
+      append_error(&error, pollset_kick_all(pollset), err_desc);
       break;
     case PO_FD:
       gpr_mu_lock(&po_at_start->owner_fd->orphan_mu);
@@ -1120,6 +1148,7 @@ static grpc_error* pollset_as_multipollable_locked(grpc_pollset* pollset,
 }
 
 static void pollset_add_fd(grpc_pollset* pollset, grpc_fd* fd) {
+  GPR_TIMER_SCOPE("pollset_add_fd", 0);
   gpr_mu_lock(&pollset->mu);
   grpc_error* error = pollset_add_fd_locked(pollset, fd);
   gpr_mu_unlock(&pollset->mu);
@@ -1168,6 +1197,7 @@ static void pollset_set_unref(grpc_pollset_set* pss) {
 }
 
 static void pollset_set_add_fd(grpc_pollset_set* pss, grpc_fd* fd) {
+  GPR_TIMER_SCOPE("pollset_set_add_fd", 0);
   if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS:%p: add fd %p (%d)", pss, fd, fd->fd);
   }
@@ -1191,6 +1221,7 @@ static void pollset_set_add_fd(grpc_pollset_set* pss, grpc_fd* fd) {
 }
 
 static void pollset_set_del_fd(grpc_pollset_set* pss, grpc_fd* fd) {
+  GPR_TIMER_SCOPE("pollset_set_del_fd", 0);
   if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS:%p: del fd %p", pss, fd);
   }
@@ -1211,6 +1242,7 @@ static void pollset_set_del_fd(grpc_pollset_set* pss, grpc_fd* fd) {
 }
 
 static void pollset_set_del_pollset(grpc_pollset_set* pss, grpc_pollset* ps) {
+  GPR_TIMER_SCOPE("pollset_set_del_pollset", 0);
   if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS:%p: del pollset %p", pss, ps);
   }
@@ -1241,6 +1273,7 @@ static grpc_error* add_fds_to_pollsets(grpc_fd** fds, size_t fd_count,
                                        size_t pollset_count,
                                        const char* err_desc, grpc_fd** out_fds,
                                        size_t* out_fd_count) {
+  GPR_TIMER_SCOPE("add_fds_to_pollsets", 0);
   grpc_error* error = GRPC_ERROR_NONE;
   for (size_t i = 0; i < fd_count; i++) {
     gpr_mu_lock(&fds[i]->orphan_mu);
@@ -1261,6 +1294,7 @@ static grpc_error* add_fds_to_pollsets(grpc_fd** fds, size_t fd_count,
 }
 
 static void pollset_set_add_pollset(grpc_pollset_set* pss, grpc_pollset* ps) {
+  GPR_TIMER_SCOPE("pollset_set_add_pollset", 0);
   if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS:%p: add pollset %p", pss, ps);
   }
@@ -1297,6 +1331,7 @@ static void pollset_set_add_pollset(grpc_pollset_set* pss, grpc_pollset* ps) {
 
 static void pollset_set_add_pollset_set(grpc_pollset_set* a,
                                         grpc_pollset_set* b) {
+  GPR_TIMER_SCOPE("pollset_set_add_pollset_set", 0);
   if (grpc_polling_trace.enabled()) {
     gpr_log(GPR_DEBUG, "PSS: merge (%p, %p)", a, b);
   }
diff --git a/src/core/lib/iomgr/ev_epollsig_linux.cc b/src/core/lib/iomgr/ev_epollsig_linux.cc
index 1518348992..c8954894ec 100644
--- a/src/core/lib/iomgr/ev_epollsig_linux.cc
+++ b/src/core/lib/iomgr/ev_epollsig_linux.cc
@@ -1024,7 +1024,7 @@ static void push_front_worker(grpc_pollset* p, grpc_pollset_worker* worker) {
 /* p->mu must be held before calling this function */
 static grpc_error* pollset_kick(grpc_pollset* p,
                                 grpc_pollset_worker* specific_worker) {
-  GPR_TIMER_BEGIN("pollset_kick", 0);
+  GPR_TIMER_SCOPE("pollset_kick", 0);
   grpc_error* error = GRPC_ERROR_NONE;
   GRPC_STATS_INC_POLLSET_KICK();
   const char* err_desc = "Kick Failure";
@@ -1032,14 +1032,13 @@ static grpc_error* pollset_kick(grpc_pollset* p,
   if (worker != nullptr) {
     if (worker == GRPC_POLLSET_KICK_BROADCAST) {
       if (pollset_has_workers(p)) {
-        GPR_TIMER_BEGIN("pollset_kick.broadcast", 0);
+        GPR_TIMER_SCOPE("pollset_kick.broadcast", 0);
         for (worker = p->root_worker.next; worker != &p->root_worker;
              worker = worker->next) {
           if (gpr_tls_get(&g_current_thread_worker) != (intptr_t)worker) {
             append_error(&error, pollset_worker_kick(worker), err_desc);
           }
         }
-        GPR_TIMER_END("pollset_kick.broadcast", 0);
       } else {
         p->kicked_without_pollers = true;
       }
@@ -1069,7 +1068,6 @@ static grpc_error* pollset_kick(grpc_pollset* p,
     }
   }
 
-  GPR_TIMER_END("pollset_kick", 0);
   GRPC_LOG_IF_ERROR("pollset_kick", GRPC_ERROR_REF(error));
   return error;
 }
@@ -1136,7 +1134,7 @@ static void finish_shutdown_locked(grpc_pollset* pollset) {
 
 /* pollset->po.mu lock must be held by the caller before calling this */
 static void pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure) {
-  GPR_TIMER_BEGIN("pollset_shutdown", 0);
+  GPR_TIMER_SCOPE("pollset_shutdown", 0);
   GPR_ASSERT(!pollset->shutting_down);
   pollset->shutting_down = true;
   pollset->shutdown_done = closure;
@@ -1150,7 +1148,6 @@ static void pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure) {
     GPR_TIMER_MARK("pollset_shutdown.finish_shutdown_locked", 0);
     finish_shutdown_locked(pollset);
   }
-  GPR_TIMER_END("pollset_shutdown", 0);
 }
 
 /* pollset_shutdown is guaranteed to be called before pollset_destroy. So other
@@ -1166,13 +1163,13 @@ static void pollset_destroy(grpc_pollset* pollset) {
 static void pollset_work_and_unlock(grpc_pollset* pollset,
                                     grpc_pollset_worker* worker, int timeout_ms,
                                     sigset_t* sig_mask, grpc_error** error) {
+  GPR_TIMER_SCOPE("pollset_work_and_unlock", 0);
   struct epoll_event ep_ev[GRPC_EPOLL_MAX_EVENTS];
   int epoll_fd = -1;
   int ep_rv;
   polling_island* pi = nullptr;
   char* err_msg;
   const char* err_desc = "pollset_work_and_unlock";
-  GPR_TIMER_BEGIN("pollset_work_and_unlock", 0);
 
   /* We need to get the epoll_fd to wait on. The epoll_fd is in inside the
      latest polling island pointed by pollset->po.pi
@@ -1187,7 +1184,6 @@ static void pollset_work_and_unlock(grpc_pollset* pollset,
   if (pollset->po.pi == nullptr) {
     pollset->po.pi = polling_island_create(nullptr, error);
     if (pollset->po.pi == nullptr) {
-      GPR_TIMER_END("pollset_work_and_unlock", 0);
       return; /* Fatal error. We cannot continue */
     }
 
@@ -1279,8 +1275,6 @@ static void pollset_work_and_unlock(grpc_pollset* pollset,
      pollset->po.pi pointer might get udpated in other parts of the
      code when there is an island merge while we are doing epoll_wait() above */
   PI_UNREF(pi, "ps_work");
-
-  GPR_TIMER_END("pollset_work_and_unlock", 0);
 }
 
 /* pollset->po.mu lock must be held by the caller before calling this.
@@ -1290,7 +1284,7 @@ static void pollset_work_and_unlock(grpc_pollset* pollset,
 static grpc_error* pollset_work(grpc_pollset* pollset,
                                 grpc_pollset_worker** worker_hdl,
                                 grpc_millis deadline) {
-  GPR_TIMER_BEGIN("pollset_work", 0);
+  GPR_TIMER_SCOPE("pollset_work", 0);
   grpc_error* error = GRPC_ERROR_NONE;
   int timeout_ms = poll_deadline_to_millis_timeout(deadline);
 
@@ -1384,15 +1378,13 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
   gpr_tls_set(&g_current_thread_pollset, (intptr_t)0);
   gpr_tls_set(&g_current_thread_worker, (intptr_t)0);
 
-  GPR_TIMER_END("pollset_work", 0);
-
   GRPC_LOG_IF_ERROR("pollset_work", GRPC_ERROR_REF(error));
   return error;
 }
 
 static void add_poll_object(poll_obj* bag, poll_obj_type bag_type,
                             poll_obj* item, poll_obj_type item_type) {
-  GPR_TIMER_BEGIN("add_poll_object", 0);
+  GPR_TIMER_SCOPE("add_poll_object", 0);
 
 #ifndef NDEBUG
   GPR_ASSERT(item->obj_type == item_type);
@@ -1535,7 +1527,6 @@ retry:
   gpr_mu_unlock(&bag->mu);
 
   GRPC_LOG_IF_ERROR("add_poll_object", error);
-  GPR_TIMER_END("add_poll_object", 0);
 }
 
 static void pollset_add_fd(grpc_pollset* pollset, grpc_fd* fd) {
diff --git a/src/core/lib/iomgr/ev_poll_posix.cc b/src/core/lib/iomgr/ev_poll_posix.cc
index 3b79728055..ad92a93beb 100644
--- a/src/core/lib/iomgr/ev_poll_posix.cc
+++ b/src/core/lib/iomgr/ev_poll_posix.cc
@@ -706,14 +706,14 @@ static void kick_append_error(grpc_error** composite, grpc_error* error) {
 static grpc_error* pollset_kick_ext(grpc_pollset* p,
                                     grpc_pollset_worker* specific_worker,
                                     uint32_t flags) {
-  GPR_TIMER_BEGIN("pollset_kick_ext", 0);
+  GPR_TIMER_SCOPE("pollset_kick_ext", 0);
   grpc_error* error = GRPC_ERROR_NONE;
   GRPC_STATS_INC_POLLSET_KICK();
 
   /* pollset->mu already held */
   if (specific_worker != nullptr) {
     if (specific_worker == GRPC_POLLSET_KICK_BROADCAST) {
-      GPR_TIMER_BEGIN("pollset_kick_ext.broadcast", 0);
+      GPR_TIMER_SCOPE("pollset_kick_ext.broadcast", 0);
       GPR_ASSERT((flags & GRPC_POLLSET_REEVALUATE_POLLING_ON_WAKEUP) == 0);
       for (specific_worker = p->root_worker.next;
            specific_worker != &p->root_worker;
@@ -722,7 +722,6 @@ static grpc_error* pollset_kick_ext(grpc_pollset* p,
             &error, grpc_wakeup_fd_wakeup(&specific_worker->wakeup_fd->fd));
       }
       p->kicked_without_pollers = true;
-      GPR_TIMER_END("pollset_kick_ext.broadcast", 0);
     } else if (gpr_tls_get(&g_current_thread_worker) !=
                (intptr_t)specific_worker) {
       GPR_TIMER_MARK("different_thread_worker", 0);
@@ -769,7 +768,6 @@ static grpc_error* pollset_kick_ext(grpc_pollset* p,
     }
   }
 
-  GPR_TIMER_END("pollset_kick_ext", 0);
   GRPC_LOG_IF_ERROR("pollset_kick_ext", GRPC_ERROR_REF(error));
   return error;
 }
@@ -864,6 +862,8 @@ static void work_combine_error(grpc_error** composite, grpc_error* error) {
 static grpc_error* pollset_work(grpc_pollset* pollset,
                                 grpc_pollset_worker** worker_hdl,
                                 grpc_millis deadline) {
+  GPR_TIMER_SCOPE("pollset_work", 0);
+
   grpc_pollset_worker worker;
   if (worker_hdl) *worker_hdl = &worker;
   grpc_error* error = GRPC_ERROR_NONE;
@@ -878,7 +878,6 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
   int locked = 1;
   int queued_work = 0;
   int keep_polling = 0;
-  GPR_TIMER_BEGIN("pollset_work", 0);
   /* this must happen before we (potentially) drop pollset->mu */
   worker.next = worker.prev = nullptr;
   worker.reevaluate_polling_on_wakeup = 0;
@@ -921,7 +920,7 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
         added_worker = 1;
         gpr_tls_set(&g_current_thread_worker, (intptr_t)&worker);
       }
-      GPR_TIMER_BEGIN("maybe_work_and_unlock", 0);
+      GPR_TIMER_SCOPE("maybe_work_and_unlock", 0);
 #define POLLOUT_CHECK (POLLOUT | POLLHUP | POLLERR)
 #define POLLIN_CHECK (POLLIN | POLLHUP | POLLERR)
 
@@ -1037,7 +1036,6 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
         gpr_free(pfds);
       }
 
-      GPR_TIMER_END("maybe_work_and_unlock", 0);
       locked = 0;
     } else {
       GPR_TIMER_MARK("pollset_work.kicked_without_pollers", 0);
@@ -1097,7 +1095,6 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
     }
   }
   if (worker_hdl) *worker_hdl = nullptr;
-  GPR_TIMER_END("pollset_work", 0);
   GRPC_LOG_IF_ERROR("pollset_work", GRPC_ERROR_REF(error));
   return error;
 }
diff --git a/src/core/lib/iomgr/ev_posix.cc b/src/core/lib/iomgr/ev_posix.cc
index 3a5714132d..8100bece8f 100644
--- a/src/core/lib/iomgr/ev_posix.cc
+++ b/src/core/lib/iomgr/ev_posix.cc
@@ -39,6 +39,18 @@
 grpc_core::TraceFlag grpc_polling_trace(false,
                                         "polling"); /* Disabled by default */
 grpc_core::DebugOnlyTraceFlag grpc_trace_fd_refcount(false, "fd_refcount");
+grpc_core::DebugOnlyTraceFlag grpc_polling_api_trace(false, "polling_api");
+
+#ifndef NDEBUG
+
+// Polling API trace only enabled in debug builds
+#define GRPC_POLLING_API_TRACE(format, ...)                   \
+  if (grpc_polling_api_trace.enabled()) {                     \
+    gpr_log(GPR_DEBUG, "(polling-api) " format, __VA_ARGS__); \
+  }
+#else
+#define GRPC_POLLING_API_TRACE(...)
+#endif
 
 /** Default poll() function - a pointer so that it can be overridden by some
  *  tests */
@@ -177,6 +189,7 @@ void grpc_event_engine_shutdown(void) {
 }
 
 grpc_fd* grpc_fd_create(int fd, const char* name) {
+  GRPC_POLLING_API_TRACE("fd_create(%d, %s)", fd, name);
   return g_event_engine->fd_create(fd, name);
 }
 
@@ -186,10 +199,14 @@ int grpc_fd_wrapped_fd(grpc_fd* fd) {
 
 void grpc_fd_orphan(grpc_fd* fd, grpc_closure* on_done, int* release_fd,
                     bool already_closed, const char* reason) {
+  GRPC_POLLING_API_TRACE("fd_orphan(%d, %p, %p, %d, %s)",
+                         grpc_fd_wrapped_fd(fd), on_done, release_fd,
+                         already_closed, reason);
   g_event_engine->fd_orphan(fd, on_done, release_fd, already_closed, reason);
 }
 
 void grpc_fd_shutdown(grpc_fd* fd, grpc_error* why) {
+  GRPC_POLLING_API_TRACE("fd_shutdown(%d)", grpc_fd_wrapped_fd(fd));
   g_event_engine->fd_shutdown(fd, why);
 }
 
@@ -208,65 +225,89 @@ void grpc_fd_notify_on_write(grpc_fd* fd, grpc_closure* closure) {
 size_t grpc_pollset_size(void) { return g_event_engine->pollset_size; }
 
 void grpc_pollset_init(grpc_pollset* pollset, gpr_mu** mu) {
+  GRPC_POLLING_API_TRACE("pollset_init(%p)", pollset);
   g_event_engine->pollset_init(pollset, mu);
 }
 
 void grpc_pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure) {
+  GRPC_POLLING_API_TRACE("pollset_shutdown(%p)", pollset);
   g_event_engine->pollset_shutdown(pollset, closure);
 }
 
 void grpc_pollset_destroy(grpc_pollset* pollset) {
+  GRPC_POLLING_API_TRACE("pollset_destroy(%p)", pollset);
   g_event_engine->pollset_destroy(pollset);
 }
 
 grpc_error* grpc_pollset_work(grpc_pollset* pollset,
                               grpc_pollset_worker** worker,
                               grpc_millis deadline) {
-  return g_event_engine->pollset_work(pollset, worker, deadline);
+  GRPC_POLLING_API_TRACE("pollset_work(%p, %" PRIdPTR ") begin", pollset,
+                         deadline);
+  grpc_error* err = g_event_engine->pollset_work(pollset, worker, deadline);
+  GRPC_POLLING_API_TRACE("pollset_work(%p, %" PRIdPTR ") end", pollset,
+                         deadline);
+  return err;
 }
 
 grpc_error* grpc_pollset_kick(grpc_pollset* pollset,
                               grpc_pollset_worker* specific_worker) {
+  GRPC_POLLING_API_TRACE("pollset_kick(%p, %p)", pollset, specific_worker);
   return g_event_engine->pollset_kick(pollset, specific_worker);
 }
 
 void grpc_pollset_add_fd(grpc_pollset* pollset, struct grpc_fd* fd) {
+  GRPC_POLLING_API_TRACE("pollset_add_fd(%p, %d)", pollset,
+                         grpc_fd_wrapped_fd(fd));
   g_event_engine->pollset_add_fd(pollset, fd);
 }
 
 grpc_pollset_set* grpc_pollset_set_create(void) {
-  return g_event_engine->pollset_set_create();
+  grpc_pollset_set* pss = g_event_engine->pollset_set_create();
+  GRPC_POLLING_API_TRACE("pollset_set_create(%p)", pss);
+  return pss;
 }
 
 void grpc_pollset_set_destroy(grpc_pollset_set* pollset_set) {
+  GRPC_POLLING_API_TRACE("pollset_set_destroy(%p)", pollset_set);
   g_event_engine->pollset_set_destroy(pollset_set);
 }
 
 void grpc_pollset_set_add_pollset(grpc_pollset_set* pollset_set,
                                   grpc_pollset* pollset) {
+  GRPC_POLLING_API_TRACE("pollset_set_add_pollset(%p, %p)", pollset_set,
+                         pollset);
   g_event_engine->pollset_set_add_pollset(pollset_set, pollset);
 }
 
 void grpc_pollset_set_del_pollset(grpc_pollset_set* pollset_set,
                                   grpc_pollset* pollset) {
+  GRPC_POLLING_API_TRACE("pollset_set_del_pollset(%p, %p)", pollset_set,
+                         pollset);
   g_event_engine->pollset_set_del_pollset(pollset_set, pollset);
 }
 
 void grpc_pollset_set_add_pollset_set(grpc_pollset_set* bag,
                                       grpc_pollset_set* item) {
+  GRPC_POLLING_API_TRACE("pollset_set_add_pollset_set(%p, %p)", bag, item);
   g_event_engine->pollset_set_add_pollset_set(bag, item);
 }
 
 void grpc_pollset_set_del_pollset_set(grpc_pollset_set* bag,
                                       grpc_pollset_set* item) {
+  GRPC_POLLING_API_TRACE("pollset_set_del_pollset_set(%p, %p)", bag, item);
   g_event_engine->pollset_set_del_pollset_set(bag, item);
 }
 
 void grpc_pollset_set_add_fd(grpc_pollset_set* pollset_set, grpc_fd* fd) {
+  GRPC_POLLING_API_TRACE("pollset_set_add_fd(%p, %d)", pollset_set,
+                         grpc_fd_wrapped_fd(fd));
   g_event_engine->pollset_set_add_fd(pollset_set, fd);
 }
 
 void grpc_pollset_set_del_fd(grpc_pollset_set* pollset_set, grpc_fd* fd) {
+  GRPC_POLLING_API_TRACE("pollset_set_del_fd(%p, %d)", pollset_set,
+                         grpc_fd_wrapped_fd(fd));
   g_event_engine->pollset_set_del_fd(pollset_set, fd);
 }
 
diff --git a/src/core/lib/iomgr/exec_ctx.cc b/src/core/lib/iomgr/exec_ctx.cc
index e005437e0a..03c833ff07 100644
--- a/src/core/lib/iomgr/exec_ctx.cc
+++ b/src/core/lib/iomgr/exec_ctx.cc
@@ -113,7 +113,7 @@ void ExecCtx::GlobalInit(void) {
 
 bool ExecCtx::Flush() {
   bool did_something = 0;
-  GPR_TIMER_BEGIN("grpc_exec_ctx_flush", 0);
+  GPR_TIMER_SCOPE("grpc_exec_ctx_flush", 0);
   for (;;) {
     if (!grpc_closure_list_empty(closure_list_)) {
       grpc_closure* c = closure_list_.head;
@@ -130,7 +130,6 @@ bool ExecCtx::Flush() {
     }
   }
   GPR_ASSERT(combiner_data_.active_combiner == nullptr);
-  GPR_TIMER_END("grpc_exec_ctx_flush", 0);
   return did_something;
 }
 
diff --git a/src/core/lib/iomgr/tcp_posix.cc b/src/core/lib/iomgr/tcp_posix.cc
index 0ec5926227..07aed2d1fd 100644
--- a/src/core/lib/iomgr/tcp_posix.cc
+++ b/src/core/lib/iomgr/tcp_posix.cc
@@ -130,7 +130,7 @@ static void run_poller(void* bp, grpc_error* error_ignored) {
     gpr_log(GPR_DEBUG, "BACKUP_POLLER:%p run", p);
   }
   gpr_mu_lock(p->pollset_mu);
-  grpc_millis deadline = grpc_core::ExecCtx::Get()->Now() + 13 * GPR_MS_PER_SEC;
+  grpc_millis deadline = grpc_core::ExecCtx::Get()->Now() + 10 * GPR_MS_PER_SEC;
   GRPC_STATS_INC_TCP_BACKUP_POLLER_POLLS();
   GRPC_LOG_IF_ERROR(
       "backup_poller:pollset_work",
@@ -368,6 +368,7 @@ static void call_read_cb(grpc_tcp* tcp, grpc_error* error) {
 
 #define MAX_READ_IOVEC 4
 static void tcp_do_read(grpc_tcp* tcp) {
+  GPR_TIMER_SCOPE("tcp_continue_read", 0);
   struct msghdr msg;
   struct iovec iov[MAX_READ_IOVEC];
   ssize_t read_bytes;
@@ -375,7 +376,6 @@ static void tcp_do_read(grpc_tcp* tcp) {
 
   GPR_ASSERT(!tcp->finished_edge);
   GPR_ASSERT(tcp->incoming_buffer->count <= MAX_READ_IOVEC);
-  GPR_TIMER_BEGIN("tcp_continue_read", 0);
 
   for (i = 0; i < tcp->incoming_buffer->count; i++) {
     iov[i].iov_base = GRPC_SLICE_START_PTR(tcp->incoming_buffer->slices[i]);
@@ -393,12 +393,11 @@ static void tcp_do_read(grpc_tcp* tcp) {
   GRPC_STATS_INC_TCP_READ_OFFER(tcp->incoming_buffer->length);
   GRPC_STATS_INC_TCP_READ_OFFER_IOV_SIZE(tcp->incoming_buffer->count);
 
-  GPR_TIMER_BEGIN("recvmsg", 0);
   do {
+    GPR_TIMER_SCOPE("recvmsg", 0);
     GRPC_STATS_INC_SYSCALL_READ();
     read_bytes = recvmsg(tcp->fd, &msg, 0);
   } while (read_bytes < 0 && errno == EINTR);
-  GPR_TIMER_END("recvmsg", read_bytes >= 0);
 
   if (read_bytes < 0) {
     /* NB: After calling call_read_cb a parallel call of the read handler may
@@ -434,8 +433,6 @@ static void tcp_do_read(grpc_tcp* tcp) {
     call_read_cb(tcp, GRPC_ERROR_NONE);
     TCP_UNREF(tcp, "read");
   }
-
-  GPR_TIMER_END("tcp_continue_read", 0);
 }
 
 static void tcp_read_allocation_done(void* tcpp, grpc_error* error) {
@@ -552,13 +549,12 @@ static bool tcp_flush(grpc_tcp* tcp, grpc_error** error) {
     GRPC_STATS_INC_TCP_WRITE_SIZE(sending_length);
     GRPC_STATS_INC_TCP_WRITE_IOV_SIZE(iov_size);
 
-    GPR_TIMER_BEGIN("sendmsg", 1);
+    GPR_TIMER_SCOPE("sendmsg", 1);
     do {
       /* TODO(klempner): Cork if this is a partial write */
       GRPC_STATS_INC_SYSCALL_WRITE();
       sent_length = sendmsg(tcp->fd, &msg, SENDMSG_FLAGS);
     } while (sent_length < 0 && errno == EINTR);
-    GPR_TIMER_END("sendmsg", 0);
 
     if (sent_length < 0) {
       if (errno == EAGAIN) {
@@ -637,6 +633,7 @@ static void tcp_handle_write(void* arg /* grpc_tcp */, grpc_error* error) {
 
 static void tcp_write(grpc_endpoint* ep, grpc_slice_buffer* buf,
                       grpc_closure* cb) {
+  GPR_TIMER_SCOPE("tcp_write", 0);
   grpc_tcp* tcp = (grpc_tcp*)ep;
   grpc_error* error = GRPC_ERROR_NONE;
 
@@ -651,11 +648,9 @@ static void tcp_write(grpc_endpoint* ep, grpc_slice_buffer* buf,
     }
   }
 
-  GPR_TIMER_BEGIN("tcp_write", 0);
   GPR_ASSERT(tcp->write_cb == nullptr);
 
   if (buf->length == 0) {
-    GPR_TIMER_END("tcp_write", 0);
     GRPC_CLOSURE_SCHED(
         cb, grpc_fd_is_shutdown(tcp->em_fd)
                 ? tcp_annotate_error(
@@ -680,8 +675,6 @@ static void tcp_write(grpc_endpoint* ep, grpc_slice_buffer* buf,
     }
     GRPC_CLOSURE_SCHED(cb, error);
   }
-
-  GPR_TIMER_END("tcp_write", 0);
 }
 
 static void tcp_add_to_pollset(grpc_endpoint* ep, grpc_pollset* pollset) {
diff --git a/src/core/lib/iomgr/wakeup_fd_eventfd.cc b/src/core/lib/iomgr/wakeup_fd_eventfd.cc
index 81cb7ee280..421ac55b00 100644
--- a/src/core/lib/iomgr/wakeup_fd_eventfd.cc
+++ b/src/core/lib/iomgr/wakeup_fd_eventfd.cc
@@ -52,15 +52,14 @@ static grpc_error* eventfd_consume(grpc_wakeup_fd* fd_info) {
 }
 
 static grpc_error* eventfd_wakeup(grpc_wakeup_fd* fd_info) {
+  GPR_TIMER_SCOPE("eventfd_wakeup", 0);
   int err;
-  GPR_TIMER_BEGIN("eventfd_wakeup", 0);
   do {
     err = eventfd_write(fd_info->read_fd, 1);
   } while (err < 0 && errno == EINTR);
   if (err < 0) {
     return GRPC_OS_ERROR(errno, "eventfd_write");
   }
-  GPR_TIMER_END("eventfd_wakeup", 0);
   return GRPC_ERROR_NONE;
 }
 
diff --git a/src/core/lib/profiling/timers.h b/src/core/lib/profiling/timers.h
index 9f11f771e6..d0188b5054 100644
--- a/src/core/lib/profiling/timers.h
+++ b/src/core/lib/profiling/timers.h
@@ -40,14 +40,10 @@ void gpr_timer_set_enabled(int enabled);
   do {                                 \
   } while (0)
 
-#define GPR_TIMER_BEGIN(tag, important) \
+#define GPR_TIMER_SCOPE(tag, important) \
   do {                                  \
   } while (0)
 
-#define GPR_TIMER_END(tag, important) \
-  do {                                \
-  } while (0)
-
 #else /* at least one profiler requested... */
 /* ... hopefully only one. */
 #if defined(GRPC_STAP_PROFILER) && defined(GRPC_BASIC_PROFILER)
@@ -64,12 +60,6 @@ void gpr_timer_set_enabled(int enabled);
 #define GPR_TIMER_MARK(tag, important) \
   gpr_timer_add_mark(tag, important, __FILE__, __LINE__);
 
-#define GPR_TIMER_BEGIN(tag, important) \
-  gpr_timer_begin(tag, important, __FILE__, __LINE__);
-
-#define GPR_TIMER_END(tag, important) \
-  gpr_timer_end(tag, important, __FILE__, __LINE__);
-
 #ifdef GRPC_STAP_PROFILER
 /* Empty placeholder for now. */
 #endif /* GRPC_STAP_PROFILER */
@@ -78,10 +68,6 @@ void gpr_timer_set_enabled(int enabled);
 /* Empty placeholder for now. */
 #endif /* GRPC_BASIC_PROFILER */
 
-#endif /* at least one profiler requested. */
-
-#if (defined(GRPC_STAP_PROFILER) + defined(GRPC_BASIC_PROFILER) + \
-     defined(GRPC_CUSTOM_PROFILER))
 namespace grpc {
 class ProfileScope {
  public:
@@ -99,10 +85,7 @@ class ProfileScope {
 #define GPR_TIMER_SCOPE(tag, important)                                        \
   ::grpc::ProfileScope _profile_scope_##__LINE__((tag), (important), __FILE__, \
                                                  __LINE__)
-#else
-#define GPR_TIMER_SCOPE(tag, important) \
-  do {                                  \
-  } while (false)
-#endif
+
+#endif /* at least one profiler requested. */
 
 #endif /* GRPC_CORE_LIB_PROFILING_TIMERS_H */
diff --git a/src/core/lib/security/transport/client_auth_filter.cc b/src/core/lib/security/transport/client_auth_filter.cc
index 045cb3e239..16814d2598 100644
--- a/src/core/lib/security/transport/client_auth_filter.cc
+++ b/src/core/lib/security/transport/client_auth_filter.cc
@@ -266,7 +266,7 @@ static void cancel_check_call_host(void* arg, grpc_error* error) {
 
 static void auth_start_transport_stream_op_batch(
     grpc_call_element* elem, grpc_transport_stream_op_batch* batch) {
-  GPR_TIMER_BEGIN("auth_start_transport_stream_op_batch", 0);
+  GPR_TIMER_SCOPE("auth_start_transport_stream_op_batch", 0);
 
   /* grab pointers to our data from the call element */
   call_data* calld = (call_data*)elem->call_data;
@@ -332,14 +332,12 @@ static void auth_start_transport_stream_op_batch(
                               grpc_schedule_on_exec_ctx));
       }
       gpr_free(call_host);
-      GPR_TIMER_END("auth_start_transport_stream_op_batch", 0);
       return; /* early exit */
     }
   }
 
   /* pass control down the stack */
   grpc_call_next_op(elem, batch);
-  GPR_TIMER_END("auth_start_transport_stream_op_batch", 0);
 }
 
 /* Constructor for call_data */
diff --git a/src/core/lib/security/transport/secure_endpoint.cc b/src/core/lib/security/transport/secure_endpoint.cc
index bd8a6cd76a..9eaa299897 100644
--- a/src/core/lib/security/transport/secure_endpoint.cc
+++ b/src/core/lib/security/transport/secure_endpoint.cc
@@ -252,7 +252,7 @@ static void flush_write_staging_buffer(secure_endpoint* ep, uint8_t** cur,
 
 static void endpoint_write(grpc_endpoint* secure_ep, grpc_slice_buffer* slices,
                            grpc_closure* cb) {
-  GPR_TIMER_BEGIN("secure_endpoint.endpoint_write", 0);
+  GPR_TIMER_SCOPE("secure_endpoint.endpoint_write", 0);
 
   unsigned i;
   tsi_result result = TSI_OK;
@@ -336,12 +336,10 @@ static void endpoint_write(grpc_endpoint* secure_ep, grpc_slice_buffer* slices,
     GRPC_CLOSURE_SCHED(
         cb, grpc_set_tsi_error_result(
                 GRPC_ERROR_CREATE_FROM_STATIC_STRING("Wrap failed"), result));
-    GPR_TIMER_END("secure_endpoint.endpoint_write", 0);
     return;
   }
 
   grpc_endpoint_write(ep->wrapped_ep, &ep->output_buffer, cb);
-  GPR_TIMER_END("secure_endpoint.endpoint_write", 0);
 }
 
 static void endpoint_shutdown(grpc_endpoint* secure_ep, grpc_error* why) {
diff --git a/src/core/lib/slice/slice_intern.cc b/src/core/lib/slice/slice_intern.cc
index fe1770b92c..cf471f30f8 100644
--- a/src/core/lib/slice/slice_intern.cc
+++ b/src/core/lib/slice/slice_intern.cc
@@ -122,13 +122,13 @@ static const grpc_slice_refcount_vtable interned_slice_sub_vtable = {
     grpc_slice_default_eq_impl, grpc_slice_default_hash_impl};
 
 static void grow_shard(slice_shard* shard) {
+  GPR_TIMER_SCOPE("grow_strtab", 0);
+
   size_t capacity = shard->capacity * 2;
   size_t i;
   interned_slice_refcount** strtab;
   interned_slice_refcount *s, *next;
 
-  GPR_TIMER_BEGIN("grow_strtab", 0);
-
   strtab = (interned_slice_refcount**)gpr_zalloc(
       sizeof(interned_slice_refcount*) * capacity);
 
@@ -140,12 +140,9 @@ static void grow_shard(slice_shard* shard) {
       strtab[idx] = s;
     }
   }
-
   gpr_free(shard->strs);
   shard->strs = strtab;
   shard->capacity = capacity;
-
-  GPR_TIMER_END("grow_strtab", 0);
 }
 
 static grpc_slice materialize(interned_slice_refcount* s) {
@@ -200,9 +197,8 @@ bool grpc_slice_is_interned(grpc_slice slice) {
 }
 
 grpc_slice grpc_slice_intern(grpc_slice slice) {
-  GPR_TIMER_BEGIN("grpc_slice_intern", 0);
+  GPR_TIMER_SCOPE("grpc_slice_intern", 0);
   if (GRPC_IS_STATIC_METADATA_STRING(slice)) {
-    GPR_TIMER_END("grpc_slice_intern", 0);
     return slice;
   }
 
@@ -212,7 +208,6 @@ grpc_slice grpc_slice_intern(grpc_slice slice) {
         static_metadata_hash[(hash + i) % GPR_ARRAY_SIZE(static_metadata_hash)];
     if (ent.hash == hash && ent.idx < GRPC_STATIC_MDSTR_COUNT &&
         grpc_slice_eq(grpc_static_slice_table[ent.idx], slice)) {
-      GPR_TIMER_END("grpc_slice_intern", 0);
       return grpc_static_slice_table[ent.idx];
     }
   }
@@ -235,7 +230,6 @@ grpc_slice grpc_slice_intern(grpc_slice slice) {
         /* and treat this as if we were never here... sshhh */
       } else {
         gpr_mu_unlock(&shard->mu);
-        GPR_TIMER_END("grpc_slice_intern", 0);
         return materialize(s);
       }
     }
@@ -264,7 +258,6 @@ grpc_slice grpc_slice_intern(grpc_slice slice) {
 
   gpr_mu_unlock(&shard->mu);
 
-  GPR_TIMER_END("grpc_slice_intern", 0);
   return materialize(s);
 }
 
diff --git a/src/core/lib/surface/alarm.cc b/src/core/lib/surface/alarm.cc
deleted file mode 100644
index f6ea016c33..0000000000
--- a/src/core/lib/surface/alarm.cc
+++ /dev/null
@@ -1,137 +0,0 @@
-/*
- *
- * Copyright 2015 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-#include <grpc/support/port_platform.h>
-
-#include <inttypes.h>
-
-#include "src/core/lib/surface/alarm_internal.h"
-
-#include <grpc/grpc.h>
-#include <grpc/support/alloc.h>
-#include <grpc/support/log.h>
-#include "src/core/lib/iomgr/timer.h"
-#include "src/core/lib/surface/completion_queue.h"
-
-grpc_core::DebugOnlyTraceFlag grpc_trace_alarm_refcount(false,
-                                                        "alarm_refcount");
-
-struct grpc_alarm {
-  gpr_refcount refs;
-  grpc_timer alarm;
-  grpc_closure on_alarm;
-  grpc_cq_completion completion;
-  /** completion queue where events about this alarm will be posted */
-  grpc_completion_queue* cq;
-  /** user supplied tag */
-  void* tag;
-};
-
-static void alarm_ref(grpc_alarm* alarm) { gpr_ref(&alarm->refs); }
-
-static void alarm_unref(grpc_alarm* alarm) {
-  if (gpr_unref(&alarm->refs)) {
-    grpc_core::ExecCtx exec_ctx;
-    if (alarm->cq != nullptr) {
-      GRPC_CQ_INTERNAL_UNREF(alarm->cq, "alarm");
-    }
-
-    gpr_free(alarm);
-  }
-}
-
-#ifndef NDEBUG
-static void alarm_ref_dbg(grpc_alarm* alarm, const char* reason,
-                          const char* file, int line) {
-  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,
-            val + 1, reason);
-  }
-
-  alarm_ref(alarm);
-}
-
-static void alarm_unref_dbg(grpc_alarm* alarm, const char* reason,
-                            const char* file, int line) {
-  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,
-            val - 1, reason);
-  }
-
-  alarm_unref(alarm);
-}
-#endif
-
-static void alarm_end_completion(void* arg, grpc_cq_completion* c) {
-  grpc_alarm* alarm = (grpc_alarm*)arg;
-  GRPC_ALARM_UNREF(alarm, "dequeue-end-op");
-}
-
-static void alarm_cb(void* arg, grpc_error* error) {
-  grpc_alarm* alarm = (grpc_alarm*)arg;
-
-  /* We are queuing an op on completion queue. This means, the alarm's structure
-     cannot be destroyed until the op is dequeued. Adding an extra ref
-     here and unref'ing when the op is dequeued will achieve this */
-  GRPC_ALARM_REF(alarm, "queue-end-op");
-  grpc_cq_end_op(alarm->cq, alarm->tag, error, alarm_end_completion,
-                 (void*)alarm, &alarm->completion);
-}
-
-grpc_alarm* grpc_alarm_create(void* reserved) {
-  grpc_alarm* alarm = (grpc_alarm*)gpr_malloc(sizeof(grpc_alarm));
-
-#ifndef NDEBUG
-  if (grpc_trace_alarm_refcount.enabled()) {
-    gpr_log(GPR_DEBUG, "Alarm:%p created (ref: 1)", alarm);
-  }
-#endif
-
-  gpr_ref_init(&alarm->refs, 1);
-  grpc_timer_init_unset(&alarm->alarm);
-  alarm->cq = nullptr;
-  GRPC_CLOSURE_INIT(&alarm->on_alarm, alarm_cb, alarm,
-                    grpc_schedule_on_exec_ctx);
-  return alarm;
-}
-
-void grpc_alarm_set(grpc_alarm* alarm, grpc_completion_queue* cq,
-                    gpr_timespec deadline, void* tag, void* reserved) {
-  grpc_core::ExecCtx exec_ctx;
-
-  GRPC_CQ_INTERNAL_REF(cq, "alarm");
-  alarm->cq = cq;
-  alarm->tag = tag;
-
-  GPR_ASSERT(grpc_cq_begin_op(cq, tag));
-  grpc_timer_init(&alarm->alarm, grpc_timespec_to_millis_round_up(deadline),
-                  &alarm->on_alarm);
-}
-
-void grpc_alarm_cancel(grpc_alarm* alarm, void* reserved) {
-  grpc_core::ExecCtx exec_ctx;
-  grpc_timer_cancel(&alarm->alarm);
-}
-
-void grpc_alarm_destroy(grpc_alarm* alarm, void* reserved) {
-  grpc_alarm_cancel(alarm, reserved);
-  GRPC_ALARM_UNREF(alarm, "alarm_destroy");
-}
diff --git a/src/core/lib/surface/alarm_internal.h b/src/core/lib/surface/alarm_internal.h
deleted file mode 100644
index 99e981234d..0000000000
--- a/src/core/lib/surface/alarm_internal.h
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- *
- * Copyright 2015-2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-#ifndef GRPC_CORE_LIB_SURFACE_ALARM_INTERNAL_H
-#define GRPC_CORE_LIB_SURFACE_ALARM_INTERNAL_H
-
-#include <grpc/support/log.h>
-#include "src/core/lib/debug/trace.h"
-
-extern grpc_core::DebugOnlyTraceFlag grpc_trace_alarm_refcount;
-
-#ifndef NDEBUG
-
-#define GRPC_ALARM_REF(a, reason) alarm_ref_dbg(a, reason, __FILE__, __LINE__)
-#define GRPC_ALARM_UNREF(a, reason) \
-  alarm_unref_dbg(a, reason, __FILE__, __LINE__)
-
-#else /* !defined(NDEBUG) */
-
-#define GRPC_ALARM_REF(a, reason) alarm_ref(a)
-#define GRPC_ALARM_UNREF(a, reason) alarm_unref(a)
-
-#endif /* defined(NDEBUG) */
-
-#endif /* GRPC_CORE_LIB_SURFACE_ALARM_INTERNAL_H */
diff --git a/src/core/lib/surface/call.cc b/src/core/lib/surface/call.cc
index ce63fa4d67..f2096d8937 100644
--- a/src/core/lib/surface/call.cc
+++ b/src/core/lib/surface/call.cc
@@ -321,12 +321,12 @@ static parent_call* get_parent_call(grpc_call* call) {
 
 grpc_error* grpc_call_create(const grpc_call_create_args* args,
                              grpc_call** out_call) {
+  GPR_TIMER_SCOPE("grpc_call_create", 0);
   size_t i, j;
   grpc_error* error = GRPC_ERROR_NONE;
   grpc_channel_stack* channel_stack =
       grpc_channel_get_channel_stack(args->channel);
   grpc_call* call;
-  GPR_TIMER_BEGIN("grpc_call_create", 0);
   size_t initial_size = grpc_channel_get_call_size_estimate(args->channel);
   GRPC_STATS_INC_CALL_INITIAL_SIZE(initial_size);
   gpr_arena* arena = gpr_arena_create(initial_size);
@@ -467,7 +467,6 @@ grpc_error* grpc_call_create(const grpc_call_create_args* args,
 
   grpc_slice_unref_internal(path);
 
-  GPR_TIMER_END("grpc_call_create", 0);
   return error;
 }
 
@@ -511,10 +510,10 @@ static void release_call(void* call, grpc_error* error) {
 
 static void set_status_value_directly(grpc_status_code status, void* dest);
 static void destroy_call(void* call, grpc_error* error) {
+  GPR_TIMER_SCOPE("destroy_call", 0);
   size_t i;
   int ii;
   grpc_call* c = (grpc_call*)call;
-  GPR_TIMER_BEGIN("destroy_call", 0);
   for (i = 0; i < 2; i++) {
     grpc_metadata_batch_destroy(
         &c->metadata_batch[1 /* is_receiving */][i /* is_initial */]);
@@ -551,7 +550,6 @@ static void destroy_call(void* call, grpc_error* error) {
   grpc_call_stack_destroy(CALL_STACK_FROM_CALL(c), &c->final_info,
                           GRPC_CLOSURE_INIT(&c->release_call, release_call, c,
                                             grpc_schedule_on_exec_ctx));
-  GPR_TIMER_END("destroy_call", 0);
 }
 
 void grpc_call_ref(grpc_call* c) { gpr_ref(&c->ext_ref); }
@@ -559,10 +557,11 @@ void grpc_call_ref(grpc_call* c) { gpr_ref(&c->ext_ref); }
 void grpc_call_unref(grpc_call* c) {
   if (!gpr_unref(&c->ext_ref)) return;
 
+  GPR_TIMER_SCOPE("grpc_call_unref", 0);
+
   child_call* cc = c->child;
   grpc_core::ExecCtx exec_ctx;
 
-  GPR_TIMER_BEGIN("grpc_call_unref", 0);
   GRPC_API_TRACE("grpc_call_unref(c=%p)", 1, (c));
 
   if (cc) {
@@ -594,8 +593,6 @@ void grpc_call_unref(grpc_call* c) {
     grpc_call_combiner_set_notify_on_cancel(&c->call_combiner, nullptr);
   }
   GRPC_CALL_INTERNAL_UNREF(c, "destroy");
-
-  GPR_TIMER_END("grpc_call_unref", 0);
 }
 
 grpc_call_error grpc_call_cancel(grpc_call* call, void* reserved) {
@@ -610,13 +607,12 @@ grpc_call_error grpc_call_cancel(grpc_call* call, void* reserved) {
 // This is called via the call combiner to start sending a batch down
 // the filter stack.
 static void execute_batch_in_call_combiner(void* arg, grpc_error* ignored) {
+  GPR_TIMER_SCOPE("execute_batch", 0);
   grpc_transport_stream_op_batch* batch = (grpc_transport_stream_op_batch*)arg;
   grpc_call* call = (grpc_call*)batch->handler_private.extra_arg;
-  GPR_TIMER_BEGIN("execute_batch", 0);
   grpc_call_element* elem = CALL_ELEM_FROM_CALL(call, 0);
   GRPC_CALL_LOG_OP(GPR_INFO, elem, batch);
   elem->filter->start_transport_stream_op_batch(elem, batch);
-  GPR_TIMER_END("execute_batch", 0);
 }
 
 // start_batch_closure points to a caller-allocated closure to be used
@@ -1036,7 +1032,7 @@ static grpc_stream_compression_algorithm decode_stream_compression(
 static void publish_app_metadata(grpc_call* call, grpc_metadata_batch* b,
                                  int is_trailing) {
   if (b->list.count == 0) return;
-  GPR_TIMER_BEGIN("publish_app_metadata", 0);
+  GPR_TIMER_SCOPE("publish_app_metadata", 0);
   grpc_metadata_array* dest;
   grpc_metadata* mdusr;
   dest = call->buffered_metadata[is_trailing];
@@ -1052,39 +1048,34 @@ static void publish_app_metadata(grpc_call* call, grpc_metadata_batch* b,
     mdusr->key = GRPC_MDKEY(l->md);
     mdusr->value = GRPC_MDVALUE(l->md);
   }
-  GPR_TIMER_END("publish_app_metadata", 0);
 }
 
 static void recv_initial_filter(grpc_call* call, grpc_metadata_batch* b) {
   if (b->idx.named.content_encoding != nullptr) {
-    GPR_TIMER_BEGIN("incoming_stream_compression_algorithm", 0);
+    GPR_TIMER_SCOPE("incoming_stream_compression_algorithm", 0);
     set_incoming_stream_compression_algorithm(
         call, decode_stream_compression(b->idx.named.content_encoding->md));
-    GPR_TIMER_END("incoming_stream_compression_algorithm", 0);
     grpc_metadata_batch_remove(b, b->idx.named.content_encoding);
   }
   if (b->idx.named.grpc_encoding != nullptr) {
-    GPR_TIMER_BEGIN("incoming_message_compression_algorithm", 0);
+    GPR_TIMER_SCOPE("incoming_message_compression_algorithm", 0);
     set_incoming_message_compression_algorithm(
         call, decode_message_compression(b->idx.named.grpc_encoding->md));
-    GPR_TIMER_END("incoming_message_compression_algorithm", 0);
     grpc_metadata_batch_remove(b, b->idx.named.grpc_encoding);
   }
   uint32_t message_encodings_accepted_by_peer = 1u;
   uint32_t stream_encodings_accepted_by_peer = 1u;
   if (b->idx.named.grpc_accept_encoding != nullptr) {
-    GPR_TIMER_BEGIN("encodings_accepted_by_peer", 0);
+    GPR_TIMER_SCOPE("encodings_accepted_by_peer", 0);
     set_encodings_accepted_by_peer(call, b->idx.named.grpc_accept_encoding->md,
                                    &message_encodings_accepted_by_peer, false);
     grpc_metadata_batch_remove(b, b->idx.named.grpc_accept_encoding);
-    GPR_TIMER_END("encodings_accepted_by_peer", 0);
   }
   if (b->idx.named.accept_encoding != nullptr) {
-    GPR_TIMER_BEGIN("stream_encodings_accepted_by_peer", 0);
+    GPR_TIMER_SCOPE("stream_encodings_accepted_by_peer", 0);
     set_encodings_accepted_by_peer(call, b->idx.named.accept_encoding->md,
                                    &stream_encodings_accepted_by_peer, true);
     grpc_metadata_batch_remove(b, b->idx.named.accept_encoding);
-    GPR_TIMER_END("stream_encodings_accepted_by_peer", 0);
   }
   call->encodings_accepted_by_peer =
       grpc_compression_bitset_from_message_stream_compression_bitset(
@@ -1523,9 +1514,8 @@ static void receiving_initial_metadata_ready(void* bctlp, grpc_error* error) {
     recv_initial_filter(call, md);
 
     /* TODO(ctiller): this could be moved into recv_initial_filter now */
-    GPR_TIMER_BEGIN("validate_filtered_metadata", 0);
+    GPR_TIMER_SCOPE("validate_filtered_metadata", 0);
     validate_filtered_metadata(bctl);
-    GPR_TIMER_END("validate_filtered_metadata", 0);
 
     if (md->deadline != GRPC_MILLIS_INF_FUTURE && !call->is_client) {
       call->send_deadline = md->deadline;
@@ -1578,6 +1568,8 @@ static void free_no_op_completion(void* p, grpc_cq_completion* completion) {
 static grpc_call_error call_start_batch(grpc_call* call, const grpc_op* ops,
                                         size_t nops, void* notify_tag,
                                         int is_notify_tag_closure) {
+  GPR_TIMER_SCOPE("grpc_call_start_batch", 0);
+
   size_t i;
   const grpc_op* op;
   batch_control* bctl;
@@ -1586,7 +1578,6 @@ static grpc_call_error call_start_batch(grpc_call* call, const grpc_op* ops,
   grpc_transport_stream_op_batch* stream_op;
   grpc_transport_stream_op_batch_payload* stream_op_payload;
 
-  GPR_TIMER_BEGIN("grpc_call_start_batch", 0);
   GRPC_CALL_LOG_BATCH(GPR_INFO, call, ops, nops, notify_tag);
 
   if (nops == 0) {
@@ -1923,7 +1914,6 @@ static grpc_call_error call_start_batch(grpc_call* call, const grpc_op* ops,
   execute_batch(call, stream_op, &bctl->start_batch);
 
 done:
-  GPR_TIMER_END("grpc_call_start_batch", 0);
   return error;
 
 done_with_error:
diff --git a/src/core/lib/surface/completion_queue.cc b/src/core/lib/surface/completion_queue.cc
index e731e2139f..8362522fa1 100644
--- a/src/core/lib/surface/completion_queue.cc
+++ b/src/core/lib/surface/completion_queue.cc
@@ -421,9 +421,9 @@ static long cq_event_queue_num_items(grpc_cq_event_queue* q) {
 grpc_completion_queue* grpc_completion_queue_create_internal(
     grpc_cq_completion_type completion_type,
     grpc_cq_polling_type polling_type) {
-  grpc_completion_queue* cq;
+  GPR_TIMER_SCOPE("grpc_completion_queue_create_internal", 0);
 
-  GPR_TIMER_BEGIN("grpc_completion_queue_create_internal", 0);
+  grpc_completion_queue* cq;
 
   GRPC_API_TRACE(
       "grpc_completion_queue_create_internal(completion_type=%d, "
@@ -452,9 +452,6 @@ grpc_completion_queue* grpc_completion_queue_create_internal(
 
   GRPC_CLOSURE_INIT(&cq->pollset_shutdown_done, on_pollset_shutdown_done, cq,
                     grpc_schedule_on_exec_ctx);
-
-  GPR_TIMER_END("grpc_completion_queue_create_internal", 0);
-
   return cq;
 }
 
@@ -622,7 +619,7 @@ static void cq_end_op_for_next(grpc_completion_queue* cq, void* tag,
                                void (*done)(void* done_arg,
                                             grpc_cq_completion* storage),
                                void* done_arg, grpc_cq_completion* storage) {
-  GPR_TIMER_BEGIN("cq_end_op_for_next", 0);
+  GPR_TIMER_SCOPE("cq_end_op_for_next", 0);
 
   if (grpc_api_trace.enabled() ||
       (grpc_trace_operation_failures.enabled() && error != GRPC_ERROR_NONE)) {
@@ -691,8 +688,6 @@ static void cq_end_op_for_next(grpc_completion_queue* cq, void* tag,
     }
   }
 
-  GPR_TIMER_END("cq_end_op_for_next", 0);
-
   GRPC_ERROR_UNREF(error);
 }
 
@@ -704,11 +699,11 @@ static void cq_end_op_for_pluck(grpc_completion_queue* cq, void* tag,
                                 void (*done)(void* done_arg,
                                              grpc_cq_completion* storage),
                                 void* done_arg, grpc_cq_completion* storage) {
+  GPR_TIMER_SCOPE("cq_end_op_for_pluck", 0);
+
   cq_pluck_data* cqd = (cq_pluck_data*)DATA_FROM_CQ(cq);
   int is_success = (error == GRPC_ERROR_NONE);
 
-  GPR_TIMER_BEGIN("cq_end_op_for_pluck", 0);
-
   if (grpc_api_trace.enabled() ||
       (grpc_trace_operation_failures.enabled() && error != GRPC_ERROR_NONE)) {
     const char* errmsg = grpc_error_string(error);
@@ -760,8 +755,6 @@ static void cq_end_op_for_pluck(grpc_completion_queue* cq, void* tag,
     }
   }
 
-  GPR_TIMER_END("cq_end_op_for_pluck", 0);
-
   GRPC_ERROR_UNREF(error);
 }
 
@@ -840,11 +833,11 @@ static void dump_pending_tags(grpc_completion_queue* cq) {}
 
 static grpc_event cq_next(grpc_completion_queue* cq, gpr_timespec deadline,
                           void* reserved) {
+  GPR_TIMER_SCOPE("grpc_completion_queue_next", 0);
+
   grpc_event ret;
   cq_next_data* cqd = (cq_next_data*)DATA_FROM_CQ(cq);
 
-  GPR_TIMER_BEGIN("grpc_completion_queue_next", 0);
-
   GRPC_API_TRACE(
       "grpc_completion_queue_next("
       "cq=%p, "
@@ -958,8 +951,6 @@ static grpc_event cq_next(grpc_completion_queue* cq, gpr_timespec deadline,
 
   GPR_ASSERT(is_finished_arg.stolen_completion == nullptr);
 
-  GPR_TIMER_END("grpc_completion_queue_next", 0);
-
   return ret;
 }
 
@@ -1078,14 +1069,14 @@ class ExecCtxPluck : public grpc_core::ExecCtx {
 
 static grpc_event cq_pluck(grpc_completion_queue* cq, void* tag,
                            gpr_timespec deadline, void* reserved) {
+  GPR_TIMER_SCOPE("grpc_completion_queue_pluck", 0);
+
   grpc_event ret;
   grpc_cq_completion* c;
   grpc_cq_completion* prev;
   grpc_pollset_worker* worker = nullptr;
   cq_pluck_data* cqd = (cq_pluck_data*)DATA_FROM_CQ(cq);
 
-  GPR_TIMER_BEGIN("grpc_completion_queue_pluck", 0);
-
   if (grpc_cq_pluck_trace.enabled()) {
     GRPC_API_TRACE(
         "grpc_completion_queue_pluck("
@@ -1191,8 +1182,6 @@ done:
 
   GPR_ASSERT(is_finished_arg.stolen_completion == nullptr);
 
-  GPR_TIMER_END("grpc_completion_queue_pluck", 0);
-
   return ret;
 }
 
@@ -1240,23 +1229,19 @@ static void cq_shutdown_pluck(grpc_completion_queue* cq) {
 /* Shutdown simply drops a ref that we reserved at creation time; if we drop
    to zero here, then enter shutdown mode and wake up any waiters */
 void grpc_completion_queue_shutdown(grpc_completion_queue* cq) {
+  GPR_TIMER_SCOPE("grpc_completion_queue_shutdown", 0);
   grpc_core::ExecCtx exec_ctx;
-  GPR_TIMER_BEGIN("grpc_completion_queue_shutdown", 0);
   GRPC_API_TRACE("grpc_completion_queue_shutdown(cq=%p)", 1, (cq));
   cq->vtable->shutdown(cq);
-
-  GPR_TIMER_END("grpc_completion_queue_shutdown", 0);
 }
 
 void grpc_completion_queue_destroy(grpc_completion_queue* cq) {
+  GPR_TIMER_SCOPE("grpc_completion_queue_destroy", 0);
   GRPC_API_TRACE("grpc_completion_queue_destroy(cq=%p)", 1, (cq));
-  GPR_TIMER_BEGIN("grpc_completion_queue_destroy", 0);
   grpc_completion_queue_shutdown(cq);
 
   grpc_core::ExecCtx exec_ctx;
   GRPC_CQ_INTERNAL_UNREF(cq, "destroy");
-
-  GPR_TIMER_END("grpc_completion_queue_destroy", 0);
 }
 
 grpc_pollset* grpc_cq_pollset(grpc_completion_queue* cq) {
diff --git a/src/core/lib/surface/init.cc b/src/core/lib/surface/init.cc
index 70329b09f4..7f7947faaa 100644
--- a/src/core/lib/surface/init.cc
+++ b/src/core/lib/surface/init.cc
@@ -42,7 +42,6 @@
 #include "src/core/lib/iomgr/timer_manager.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/slice/slice_internal.h"
-#include "src/core/lib/surface/alarm_internal.h"
 #include "src/core/lib/surface/api_trace.h"
 #include "src/core/lib/surface/call.h"
 #include "src/core/lib/surface/channel_init.h"
@@ -162,9 +161,9 @@ void grpc_shutdown(void) {
     {
       grpc_core::ExecCtx exec_ctx(0);
       {
-        grpc_executor_shutdown();
         grpc_timer_manager_set_threading(
             false);  // shutdown timer_manager thread
+        grpc_executor_shutdown();
         for (i = g_number_of_plugins; i >= 0; i--) {
           if (g_all_of_the_plugins[i].destroy != nullptr) {
             g_all_of_the_plugins[i].destroy();
diff --git a/src/core/lib/surface/version.cc b/src/core/lib/surface/version.cc
index 19498a6df7..153b6e0297 100644
--- a/src/core/lib/surface/version.cc
+++ b/src/core/lib/surface/version.cc
@@ -21,6 +21,6 @@
 
 #include <grpc/grpc.h>
 
-const char* grpc_version_string(void) { return "5.0.0-dev"; }
+const char* grpc_version_string(void) { return "6.0.0-dev"; }
 
-const char* grpc_g_stands_for(void) { return "glamorous"; }
+const char* grpc_g_stands_for(void) { return "glossy"; }
diff --git a/src/core/lib/transport/metadata.cc b/src/core/lib/transport/metadata.cc
index 652222bd0b..cc1edd586f 100644
--- a/src/core/lib/transport/metadata.cc
+++ b/src/core/lib/transport/metadata.cc
@@ -166,12 +166,13 @@ static void ref_md_locked(mdtab_shard* shard,
 }
 
 static void gc_mdtab(mdtab_shard* shard) {
+  GPR_TIMER_SCOPE("gc_mdtab", 0);
+
   size_t i;
   interned_metadata** prev_next;
   interned_metadata *md, *next;
   gpr_atm num_freed = 0;
 
-  GPR_TIMER_BEGIN("gc_mdtab", 0);
   for (i = 0; i < shard->capacity; i++) {
     prev_next = &shard->elems[i];
     for (md = shard->elems[i]; md; md = next) {
@@ -194,18 +195,17 @@ static void gc_mdtab(mdtab_shard* shard) {
     }
   }
   gpr_atm_no_barrier_fetch_add(&shard->free_estimate, -num_freed);
-  GPR_TIMER_END("gc_mdtab", 0);
 }
 
 static void grow_mdtab(mdtab_shard* shard) {
+  GPR_TIMER_SCOPE("grow_mdtab", 0);
+
   size_t capacity = shard->capacity * 2;
   size_t i;
   interned_metadata** mdtab;
   interned_metadata *md, *next;
   uint32_t hash;
 
-  GPR_TIMER_BEGIN("grow_mdtab", 0);
-
   mdtab =
       (interned_metadata**)gpr_zalloc(sizeof(interned_metadata*) * capacity);
 
@@ -220,12 +220,9 @@ static void grow_mdtab(mdtab_shard* shard) {
       mdtab[idx] = md;
     }
   }
-
   gpr_free(shard->elems);
   shard->elems = mdtab;
   shard->capacity = capacity;
-
-  GPR_TIMER_END("grow_mdtab", 0);
 }
 
 static void rehash_mdtab(mdtab_shard* shard) {
@@ -280,7 +277,7 @@ grpc_mdelem grpc_mdelem_create(
   mdtab_shard* shard = &g_shards[SHARD_IDX(hash)];
   size_t idx;
 
-  GPR_TIMER_BEGIN("grpc_mdelem_from_metadata_strings", 0);
+  GPR_TIMER_SCOPE("grpc_mdelem_from_metadata_strings", 0);
 
   gpr_mu_lock(&shard->mu);
 
@@ -290,7 +287,6 @@ grpc_mdelem grpc_mdelem_create(
     if (grpc_slice_eq(key, md->key) && grpc_slice_eq(value, md->value)) {
       REF_MD_LOCKED(shard, md);
       gpr_mu_unlock(&shard->mu);
-      GPR_TIMER_END("grpc_mdelem_from_metadata_strings", 0);
       return GRPC_MAKE_MDELEM(md, GRPC_MDELEM_STORAGE_INTERNED);
     }
   }
@@ -323,8 +319,6 @@ grpc_mdelem grpc_mdelem_create(
 
   gpr_mu_unlock(&shard->mu);
 
-  GPR_TIMER_END("grpc_mdelem_from_metadata_strings", 0);
-
   return GRPC_MAKE_MDELEM(md, GRPC_MDELEM_STORAGE_INTERNED);
 }
 
diff --git a/src/core/plugin_registry/grpc_cronet_plugin_registry.cc b/src/core/plugin_registry/grpc_cronet_plugin_registry.cc
index 101e29c481..fe5eb28f05 100644
--- a/src/core/plugin_registry/grpc_cronet_plugin_registry.cc
+++ b/src/core/plugin_registry/grpc_cronet_plugin_registry.cc
@@ -26,8 +26,8 @@ void grpc_deadline_filter_init(void);
 void grpc_deadline_filter_shutdown(void);
 void grpc_client_channel_init(void);
 void grpc_client_channel_shutdown(void);
-void grpc_tsi_gts_init(void);
-void grpc_tsi_gts_shutdown(void);
+void grpc_tsi_alts_init(void);
+void grpc_tsi_alts_shutdown(void);
 void grpc_server_load_reporting_plugin_init(void);
 void grpc_server_load_reporting_plugin_shutdown(void);
 
@@ -40,8 +40,8 @@ void grpc_register_built_in_plugins(void) {
                        grpc_deadline_filter_shutdown);
   grpc_register_plugin(grpc_client_channel_init,
                        grpc_client_channel_shutdown);
-  grpc_register_plugin(grpc_tsi_gts_init,
-                       grpc_tsi_gts_shutdown);
+  grpc_register_plugin(grpc_tsi_alts_init,
+                       grpc_tsi_alts_shutdown);
   grpc_register_plugin(grpc_server_load_reporting_plugin_init,
                        grpc_server_load_reporting_plugin_shutdown);
 }
diff --git a/src/core/plugin_registry/grpc_plugin_registry.cc b/src/core/plugin_registry/grpc_plugin_registry.cc
index 89be351785..fdf9acc09c 100644
--- a/src/core/plugin_registry/grpc_plugin_registry.cc
+++ b/src/core/plugin_registry/grpc_plugin_registry.cc
@@ -22,8 +22,8 @@ void grpc_http_filters_init(void);
 void grpc_http_filters_shutdown(void);
 void grpc_chttp2_plugin_init(void);
 void grpc_chttp2_plugin_shutdown(void);
-void grpc_tsi_gts_init(void);
-void grpc_tsi_gts_shutdown(void);
+void grpc_tsi_alts_init(void);
+void grpc_tsi_alts_shutdown(void);
 void grpc_deadline_filter_init(void);
 void grpc_deadline_filter_shutdown(void);
 void grpc_client_channel_init(void);
@@ -58,8 +58,8 @@ void grpc_register_built_in_plugins(void) {
                        grpc_http_filters_shutdown);
   grpc_register_plugin(grpc_chttp2_plugin_init,
                        grpc_chttp2_plugin_shutdown);
-  grpc_register_plugin(grpc_tsi_gts_init,
-                       grpc_tsi_gts_shutdown);
+  grpc_register_plugin(grpc_tsi_alts_init,
+                       grpc_tsi_alts_shutdown);
   grpc_register_plugin(grpc_deadline_filter_init,
                        grpc_deadline_filter_shutdown);
   grpc_register_plugin(grpc_client_channel_init,
diff --git a/src/core/tsi/gts_transport_security.cc b/src/core/tsi/alts_transport_security.cc
index 2b099773c4..ddd75cbd02 100644
--- a/src/core/tsi/gts_transport_security.cc
+++ b/src/core/tsi/alts_transport_security.cc
@@ -16,25 +16,27 @@
  *
  */
 
-#include "src/core/tsi/gts_transport_security.h"
+#include "src/core/tsi/alts_transport_security.h"
 
 #include <string.h>
 
-static gts_shared_resource g_gts_resource;
+static alts_shared_resource g_alts_resource;
 
-gts_shared_resource* gts_get_shared_resource(void) { return &g_gts_resource; }
+alts_shared_resource* alts_get_shared_resource(void) {
+  return &g_alts_resource;
+}
 
-void grpc_tsi_gts_init() {
-  memset(&g_gts_resource, 0, sizeof(gts_shared_resource));
-  gpr_mu_init(&g_gts_resource.mu);
+void grpc_tsi_alts_init() {
+  memset(&g_alts_resource, 0, sizeof(alts_shared_resource));
+  gpr_mu_init(&g_alts_resource.mu);
 }
 
-void grpc_tsi_gts_shutdown() {
-  gpr_mu_destroy(&g_gts_resource.mu);
-  if (g_gts_resource.cq == nullptr) {
+void grpc_tsi_alts_shutdown() {
+  gpr_mu_destroy(&g_alts_resource.mu);
+  if (g_alts_resource.cq == nullptr) {
     return;
   }
-  grpc_completion_queue_destroy(g_gts_resource.cq);
-  grpc_channel_destroy(g_gts_resource.channel);
-  gpr_thd_join(g_gts_resource.thread_id);
+  grpc_completion_queue_destroy(g_alts_resource.cq);
+  grpc_channel_destroy(g_alts_resource.channel);
+  gpr_thd_join(g_alts_resource.thread_id);
 }
diff --git a/src/core/tsi/gts_transport_security.h b/src/core/tsi/alts_transport_security.h
index 23b2b66fb3..c90e31478e 100644
--- a/src/core/tsi/gts_transport_security.h
+++ b/src/core/tsi/alts_transport_security.h
@@ -16,22 +16,22 @@
  *
  */
 
-#ifndef GRPC_CORE_TSI_GTS_TRANSPORT_SECURITY_H
-#define GRPC_CORE_TSI_GTS_TRANSPORT_SECURITY_H
+#ifndef GRPC_CORE_TSI_ALTS_TRANSPORT_SECURITY_H
+#define GRPC_CORE_TSI_ALTS_TRANSPORT_SECURITY_H
 
 #include <grpc/grpc.h>
 #include <grpc/support/sync.h>
 #include <grpc/support/thd.h>
 
-typedef struct gts_shared_resource {
+typedef struct alts_shared_resource {
   gpr_thd_id thread_id;
   grpc_channel* channel;
   grpc_completion_queue* cq;
   gpr_mu mu;
-} gts_shared_resource;
+} alts_shared_resource;
 
-/* This method returns the address of gts_shared_resource object shared by all
+/* This method returns the address of alts_shared_resource object shared by all
  *    TSI handshakes. */
-gts_shared_resource* gts_get_shared_resource(void);
+alts_shared_resource* alts_get_shared_resource(void);
 
-#endif /* GRPC_CORE_TSI_GTS_TRANSPORT_SECURITY_H */
+#endif /* GRPC_CORE_TSI_ALTS_TRANSPORT_SECURITY_H */