Move ExecCtx to grpc_core namespace. Make exec_ctx a private static in ExecCtx and some minor changes

80 files changed, 373 insertions, 323 deletions

diff --git a/src/core/ext/filters/client_channel/backup_poller.cc b/src/core/ext/filters/client_channel/backup_poller.cc
index dbdcd53ef5..ea9fb2cae1 100644
--- a/src/core/ext/filters/client_channel/backup_poller.cc
+++ b/src/core/ext/filters/client_channel/backup_poller.cc
@@ -112,10 +112,12 @@ static void run_poller(void* arg, grpc_error* error) {
     backup_poller_shutdown_unref(p);
     return;
   }
-  grpc_error* err = grpc_pollset_work(p->pollset, NULL, ExecCtx::Get()->Now());
+  grpc_error* err =
+      grpc_pollset_work(p->pollset, NULL, grpc_core::ExecCtx::Get()->Now());
   gpr_mu_unlock(p->pollset_mu);
   GRPC_LOG_IF_ERROR("Run client channel backup poller", err);
-  grpc_timer_init(&p->polling_timer, ExecCtx::Get()->Now() + g_poll_interval_ms,
+  grpc_timer_init(&p->polling_timer,
+                  grpc_core::ExecCtx::Get()->Now() + g_poll_interval_ms,
                   &p->run_poller_closure);
 }
 
@@ -137,7 +139,7 @@ void grpc_client_channel_start_backup_polling(
     GRPC_CLOSURE_INIT(&g_poller->run_poller_closure, run_poller, g_poller,
                       grpc_schedule_on_exec_ctx);
     grpc_timer_init(&g_poller->polling_timer,
-                    ExecCtx::Get()->Now() + g_poll_interval_ms,
+                    grpc_core::ExecCtx::Get()->Now() + g_poll_interval_ms,
                     &g_poller->run_poller_closure);
   }
 
diff --git a/src/core/ext/filters/client_channel/channel_connectivity.cc b/src/core/ext/filters/client_channel/channel_connectivity.cc
index 0ceedb9f86..c949e52bd4 100644
--- a/src/core/ext/filters/client_channel/channel_connectivity.cc
+++ b/src/core/ext/filters/client_channel/channel_connectivity.cc
@@ -33,7 +33,7 @@ grpc_connectivity_state grpc_channel_check_connectivity_state(
   /* forward through to the underlying client channel */
   grpc_channel_element* client_channel_elem =
       grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_connectivity_state state;
   GRPC_API_TRACE(
       "grpc_channel_check_connectivity_state(channel=%p, try_to_connect=%d)", 2,
@@ -198,7 +198,7 @@ void grpc_channel_watch_connectivity_state(
     gpr_timespec deadline, grpc_completion_queue* cq, void* tag) {
   grpc_channel_element* client_channel_elem =
       grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   state_watcher* w = (state_watcher*)gpr_malloc(sizeof(*w));
 
   GRPC_API_TRACE(
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
index 63cf417c4e..e757777aec 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
@@ -1122,7 +1122,7 @@ static void start_picking_locked(glb_lb_policy* glb_policy) {
   if (glb_policy->lb_fallback_timeout_ms > 0 &&
       glb_policy->serverlist == NULL && !glb_policy->fallback_timer_active) {
     grpc_millis deadline =
-        ExecCtx::Get()->Now() + glb_policy->lb_fallback_timeout_ms;
+        grpc_core::ExecCtx::Get()->Now() + glb_policy->lb_fallback_timeout_ms;
     GRPC_LB_POLICY_WEAK_REF(&glb_policy->base, "grpclb_fallback_timer");
     GRPC_CLOSURE_INIT(&glb_policy->lb_on_fallback, lb_on_fallback_timer_locked,
                       glb_policy,
@@ -1271,7 +1271,7 @@ static void maybe_restart_lb_call(glb_lb_policy* glb_policy) {
     if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
       gpr_log(GPR_DEBUG, "[grpclb %p] Connection to LB server lost...",
               glb_policy);
-      grpc_millis timeout = next_try - ExecCtx::Get()->Now();
+      grpc_millis timeout = next_try - grpc_core::ExecCtx::Get()->Now();
       if (timeout > 0) {
         gpr_log(GPR_DEBUG,
                 "[grpclb %p] ... retry_timer_active in %" PRIuPTR "ms.",
@@ -1297,7 +1297,8 @@ static void send_client_load_report_locked(void* arg, grpc_error* error);
 
 static void schedule_next_client_load_report(glb_lb_policy* glb_policy) {
   const grpc_millis next_client_load_report_time =
-      ExecCtx::Get()->Now() + glb_policy->client_stats_report_interval;
+      grpc_core::ExecCtx::Get()->Now() +
+      glb_policy->client_stats_report_interval;
   GRPC_CLOSURE_INIT(&glb_policy->client_load_report_closure,
                     send_client_load_report_locked, glb_policy,
                     grpc_combiner_scheduler(glb_policy->base.combiner));
@@ -1392,7 +1393,7 @@ static void lb_call_init_locked(glb_lb_policy* glb_policy) {
   grpc_millis deadline =
       glb_policy->lb_call_timeout_ms == 0
           ? GRPC_MILLIS_INF_FUTURE
-          : ExecCtx::Get()->Now() + glb_policy->lb_call_timeout_ms;
+          : grpc_core::ExecCtx::Get()->Now() + glb_policy->lb_call_timeout_ms;
   glb_policy->lb_call = grpc_channel_create_pollset_set_call(
       glb_policy->lb_channel, NULL, GRPC_PROPAGATE_DEFAULTS,
       glb_policy->base.interested_parties,
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 f0543964ae..5ac5d37a54 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
@@ -265,7 +265,7 @@ static void dns_ares_on_resolved_locked(void* arg, grpc_error* error) {
     gpr_log(GPR_DEBUG, "dns resolution failed: %s", msg);
     grpc_millis next_try =
         grpc_backoff_step(&r->backoff_state).next_attempt_start_time;
-    grpc_millis timeout = next_try - ExecCtx::Get()->Now();
+    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);
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 925223d189..06af5bf0b2 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
@@ -213,7 +213,7 @@ static void on_hostbyname_done_cb(void* arg, int status, int timeouts,
 static void on_srv_query_done_cb(void* arg, int status, int timeouts,
                                  unsigned char* abuf, int alen) {
   grpc_ares_request* r = (grpc_ares_request*)arg;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   gpr_log(GPR_DEBUG, "on_query_srv_done_cb");
   if (status == ARES_SUCCESS) {
     gpr_log(GPR_DEBUG, "on_query_srv_done_cb ARES_SUCCESS");
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 10404ec4ef..82cd28fb2b 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
@@ -163,7 +163,7 @@ static void dns_on_resolved_locked(void* arg, grpc_error* error) {
   } else {
     grpc_millis next_try =
         grpc_backoff_step(&r->backoff_state).next_attempt_start_time;
-    grpc_millis timeout = next_try - ExecCtx::Get()->Now();
+    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);
diff --git a/src/core/ext/filters/client_channel/subchannel.cc b/src/core/ext/filters/client_channel/subchannel.cc
index 98f96b5750..61adb984f3 100644
--- a/src/core/ext/filters/client_channel/subchannel.cc
+++ b/src/core/ext/filters/client_channel/subchannel.cc
@@ -458,7 +458,8 @@ static void maybe_start_connecting_locked(grpc_subchannel* c) {
     GPR_ASSERT(!c->have_alarm);
     c->have_alarm = true;
     const grpc_millis time_til_next =
-        c->backoff_result.next_attempt_start_time - ExecCtx::Get()->Now();
+        c->backoff_result.next_attempt_start_time -
+        grpc_core::ExecCtx::Get()->Now();
     if (time_til_next <= 0) {
       gpr_log(GPR_INFO, "Retry immediately");
     } else {
diff --git a/src/core/ext/filters/client_channel/subchannel_index.cc b/src/core/ext/filters/client_channel/subchannel_index.cc
index fbab57769c..b7b7472aff 100644
--- a/src/core/ext/filters/client_channel/subchannel_index.cc
+++ b/src/core/ext/filters/client_channel/subchannel_index.cc
@@ -133,7 +133,7 @@ void grpc_subchannel_index_shutdown(void) {
 void grpc_subchannel_index_unref(void) {
   if (gpr_unref(&g_refcount)) {
     gpr_mu_destroy(&g_mu);
-    gpr_avl_unref(g_subchannel_index, ExecCtx::Get());
+    gpr_avl_unref(g_subchannel_index, grpc_core::ExecCtx::Get());
   }
 }
 
@@ -143,12 +143,13 @@ grpc_subchannel* grpc_subchannel_index_find(grpc_subchannel_key* key) {
   // Lock, and take a reference to the subchannel index.
   // We don't need to do the search under a lock as avl's are immutable.
   gpr_mu_lock(&g_mu);
-  gpr_avl index = gpr_avl_ref(g_subchannel_index, ExecCtx::Get());
+  gpr_avl index = gpr_avl_ref(g_subchannel_index, grpc_core::ExecCtx::Get());
   gpr_mu_unlock(&g_mu);
 
   grpc_subchannel* c = GRPC_SUBCHANNEL_REF_FROM_WEAK_REF(
-      (grpc_subchannel*)gpr_avl_get(index, key, ExecCtx::Get()), "index_find");
-  gpr_avl_unref(index, ExecCtx::Get());
+      (grpc_subchannel*)gpr_avl_get(index, key, grpc_core::ExecCtx::Get()),
+      "index_find");
+  gpr_avl_unref(index, grpc_core::ExecCtx::Get());
 
   return c;
 }
@@ -164,11 +165,11 @@ grpc_subchannel* grpc_subchannel_index_register(grpc_subchannel_key* key,
     // Compare and swap loop:
     // - take a reference to the current index
     gpr_mu_lock(&g_mu);
-    gpr_avl index = gpr_avl_ref(g_subchannel_index, ExecCtx::Get());
+    gpr_avl index = gpr_avl_ref(g_subchannel_index, grpc_core::ExecCtx::Get());
     gpr_mu_unlock(&g_mu);
 
     // - Check to see if a subchannel already exists
-    c = (grpc_subchannel*)gpr_avl_get(index, key, ExecCtx::Get());
+    c = (grpc_subchannel*)gpr_avl_get(index, key, grpc_core::ExecCtx::Get());
     if (c != NULL) {
       c = GRPC_SUBCHANNEL_REF_FROM_WEAK_REF(c, "index_register");
     }
@@ -177,10 +178,11 @@ grpc_subchannel* grpc_subchannel_index_register(grpc_subchannel_key* key,
       need_to_unref_constructed = true;
     } else {
       // no -> update the avl and compare/swap
-      gpr_avl updated = gpr_avl_add(
-          gpr_avl_ref(index, ExecCtx::Get()), subchannel_key_copy(key),
-          GRPC_SUBCHANNEL_WEAK_REF(constructed, "index_register"),
-          ExecCtx::Get());
+      gpr_avl updated =
+          gpr_avl_add(gpr_avl_ref(index, grpc_core::ExecCtx::Get()),
+                      subchannel_key_copy(key),
+                      GRPC_SUBCHANNEL_WEAK_REF(constructed, "index_register"),
+                      grpc_core::ExecCtx::Get());
 
       // it may happen (but it's expected to be unlikely)
       // that some other thread has changed the index:
@@ -192,9 +194,9 @@ grpc_subchannel* grpc_subchannel_index_register(grpc_subchannel_key* key,
       }
       gpr_mu_unlock(&g_mu);
 
-      gpr_avl_unref(updated, ExecCtx::Get());
+      gpr_avl_unref(updated, grpc_core::ExecCtx::Get());
     }
-    gpr_avl_unref(index, ExecCtx::Get());
+    gpr_avl_unref(index, grpc_core::ExecCtx::Get());
   }
 
   if (need_to_unref_constructed) {
@@ -211,22 +213,23 @@ void grpc_subchannel_index_unregister(grpc_subchannel_key* key,
     // Compare and swap loop:
     // - take a reference to the current index
     gpr_mu_lock(&g_mu);
-    gpr_avl index = gpr_avl_ref(g_subchannel_index, ExecCtx::Get());
+    gpr_avl index = gpr_avl_ref(g_subchannel_index, grpc_core::ExecCtx::Get());
     gpr_mu_unlock(&g_mu);
 
     // Check to see if this key still refers to the previously
     // registered subchannel
     grpc_subchannel* c =
-        (grpc_subchannel*)gpr_avl_get(index, key, ExecCtx::Get());
+        (grpc_subchannel*)gpr_avl_get(index, key, grpc_core::ExecCtx::Get());
     if (c != constructed) {
-      gpr_avl_unref(index, ExecCtx::Get());
+      gpr_avl_unref(index, grpc_core::ExecCtx::Get());
       break;
     }
 
     // compare and swap the update (some other thread may have
     // mutated the index behind us)
     gpr_avl updated =
-        gpr_avl_remove(gpr_avl_ref(index, ExecCtx::Get()), key, ExecCtx::Get());
+        gpr_avl_remove(gpr_avl_ref(index, grpc_core::ExecCtx::Get()), key,
+                       grpc_core::ExecCtx::Get());
 
     gpr_mu_lock(&g_mu);
     if (index.root == g_subchannel_index.root) {
@@ -235,8 +238,8 @@ void grpc_subchannel_index_unregister(grpc_subchannel_key* key,
     }
     gpr_mu_unlock(&g_mu);
 
-    gpr_avl_unref(updated, ExecCtx::Get());
-    gpr_avl_unref(index, ExecCtx::Get());
+    gpr_avl_unref(updated, grpc_core::ExecCtx::Get());
+    gpr_avl_unref(index, grpc_core::ExecCtx::Get());
   }
 }
 
diff --git a/src/core/ext/filters/max_age/max_age_filter.cc b/src/core/ext/filters/max_age/max_age_filter.cc
index 015a3ce124..f89e8c730d 100644
--- a/src/core/ext/filters/max_age/max_age_filter.cc
+++ b/src/core/ext/filters/max_age/max_age_filter.cc
@@ -99,9 +99,10 @@ static void increase_call_count(channel_data* chand) {
 static void decrease_call_count(channel_data* chand) {
   if (gpr_atm_full_fetch_add(&chand->call_count, -1) == 1) {
     GRPC_CHANNEL_STACK_REF(chand->channel_stack, "max_age max_idle_timer");
-    grpc_timer_init(&chand->max_idle_timer,
-                    ExecCtx::Get()->Now() + chand->max_connection_idle,
-                    &chand->close_max_idle_channel);
+    grpc_timer_init(
+        &chand->max_idle_timer,
+        grpc_core::ExecCtx::Get()->Now() + chand->max_connection_idle,
+        &chand->close_max_idle_channel);
   }
 }
 
@@ -121,7 +122,7 @@ static void start_max_age_timer_after_init(void* arg, grpc_error* error) {
   chand->max_age_timer_pending = true;
   GRPC_CHANNEL_STACK_REF(chand->channel_stack, "max_age max_age_timer");
   grpc_timer_init(&chand->max_age_timer,
-                  ExecCtx::Get()->Now() + chand->max_connection_age,
+                  grpc_core::ExecCtx::Get()->Now() + chand->max_connection_age,
                   &chand->close_max_age_channel);
   gpr_mu_unlock(&chand->max_age_timer_mu);
   grpc_transport_op* op = grpc_make_transport_op(NULL);
@@ -138,11 +139,12 @@ static void start_max_age_grace_timer_after_goaway_op(void* arg,
   gpr_mu_lock(&chand->max_age_timer_mu);
   chand->max_age_grace_timer_pending = true;
   GRPC_CHANNEL_STACK_REF(chand->channel_stack, "max_age max_age_grace_timer");
-  grpc_timer_init(&chand->max_age_grace_timer,
-                  chand->max_connection_age_grace == GRPC_MILLIS_INF_FUTURE
-                      ? GRPC_MILLIS_INF_FUTURE
-                      : ExecCtx::Get()->Now() + chand->max_connection_age_grace,
-                  &chand->force_close_max_age_channel);
+  grpc_timer_init(
+      &chand->max_age_grace_timer,
+      chand->max_connection_age_grace == GRPC_MILLIS_INF_FUTURE
+          ? GRPC_MILLIS_INF_FUTURE
+          : grpc_core::ExecCtx::Get()->Now() + chand->max_connection_age_grace,
+      &chand->force_close_max_age_channel);
   gpr_mu_unlock(&chand->max_age_timer_mu);
   GRPC_CHANNEL_STACK_UNREF(chand->channel_stack,
                            "max_age start_max_age_grace_timer_after_goaway_op");
diff --git a/src/core/ext/transport/chttp2/client/insecure/channel_create.cc b/src/core/ext/transport/chttp2/client/insecure/channel_create.cc
index 3afca884ca..fec61281c3 100644
--- a/src/core/ext/transport/chttp2/client/insecure/channel_create.cc
+++ b/src/core/ext/transport/chttp2/client/insecure/channel_create.cc
@@ -80,7 +80,7 @@ static grpc_client_channel_factory client_channel_factory = {
 grpc_channel* grpc_insecure_channel_create(const char* target,
                                            const grpc_channel_args* args,
                                            void* reserved) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_API_TRACE(
       "grpc_insecure_channel_create(target=%s, args=%p, reserved=%p)", 3,
       (target, args, reserved));
diff --git a/src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc b/src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc
index b0eff1c992..c713ce1960 100644
--- a/src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc
+++ b/src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc
@@ -37,7 +37,7 @@
 
 grpc_channel* grpc_insecure_channel_create_from_fd(
     const char* target, int fd, const grpc_channel_args* args) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_API_TRACE("grpc_insecure_channel_create(target=%p, fd=%d, args=%p)", 3,
                  (target, fd, args));
 
diff --git a/src/core/ext/transport/chttp2/client/secure/secure_channel_create.cc b/src/core/ext/transport/chttp2/client/secure/secure_channel_create.cc
index bebc38c248..a328126263 100644
--- a/src/core/ext/transport/chttp2/client/secure/secure_channel_create.cc
+++ b/src/core/ext/transport/chttp2/client/secure/secure_channel_create.cc
@@ -190,7 +190,7 @@ grpc_channel* grpc_secure_channel_create(grpc_channel_credentials* creds,
                                          const char* target,
                                          const grpc_channel_args* args,
                                          void* reserved) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_API_TRACE(
       "grpc_secure_channel_create(creds=%p, target=%s, args=%p, "
       "reserved=%p)",
diff --git a/src/core/ext/transport/chttp2/server/chttp2_server.cc b/src/core/ext/transport/chttp2/server/chttp2_server.cc
index bbcfb1b195..97b6ad38de 100644
--- a/src/core/ext/transport/chttp2/server/chttp2_server.cc
+++ b/src/core/ext/transport/chttp2/server/chttp2_server.cc
@@ -132,7 +132,8 @@ static void on_accept(void* arg, grpc_endpoint* tcp,
                        connection_state->handshake_mgr);
   // TODO(roth): We should really get this timeout value from channel
   // args instead of hard-coding it.
-  const grpc_millis deadline = ExecCtx::Get()->Now() + 120 * GPR_MS_PER_SEC;
+  const grpc_millis deadline =
+      grpc_core::ExecCtx::Get()->Now() + 120 * GPR_MS_PER_SEC;
   grpc_handshake_manager_do_handshake(connection_state->handshake_mgr, tcp,
                                       state->args, deadline, acceptor,
                                       on_handshake_done, connection_state);
@@ -161,10 +162,10 @@ static void tcp_server_shutdown_complete(void* arg, grpc_error* error) {
   gpr_mu_unlock(&state->mu);
   // Flush queued work before destroying handshaker factory, since that
   // may do a synchronous unref.
-  ExecCtx::Get()->Flush();
+  grpc_core::ExecCtx::Get()->Flush();
   if (destroy_done != NULL) {
     destroy_done->cb(destroy_done->cb_arg, GRPC_ERROR_REF(error));
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
   }
   grpc_channel_args_destroy(state->args);
   gpr_mu_destroy(&state->mu);
diff --git a/src/core/ext/transport/chttp2/server/insecure/server_chttp2.cc b/src/core/ext/transport/chttp2/server/insecure/server_chttp2.cc
index 6cbb26a349..826886c961 100644
--- a/src/core/ext/transport/chttp2/server/insecure/server_chttp2.cc
+++ b/src/core/ext/transport/chttp2/server/insecure/server_chttp2.cc
@@ -26,7 +26,7 @@
 #include "src/core/lib/surface/server.h"
 
 int grpc_server_add_insecure_http2_port(grpc_server* server, const char* addr) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   int port_num = 0;
   GRPC_API_TRACE("grpc_server_add_insecure_http2_port(server=%p, addr=%s)", 2,
                  (server, addr));
diff --git a/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.cc b/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.cc
index e5419e5e6e..11b3d710df 100644
--- a/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.cc
+++ b/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.cc
@@ -38,7 +38,7 @@ void grpc_server_add_insecure_channel_from_fd(grpc_server* server,
                                               void* reserved, int fd) {
   GPR_ASSERT(reserved == NULL);
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   char* name;
   gpr_asprintf(&name, "fd:%d", fd);
 
diff --git a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.cc b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.cc
index aeae8f42e3..827f0020bb 100644
--- a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.cc
+++ b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.cc
@@ -36,7 +36,7 @@
 
 int grpc_server_add_secure_http2_port(grpc_server* server, const char* addr,
                                       grpc_server_credentials* creds) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_error* err = GRPC_ERROR_NONE;
   grpc_server_security_connector* sc = NULL;
   int port_num = 0;
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.cc b/src/core/ext/transport/chttp2/transport/chttp2_transport.cc
index e49e26fc35..a2861dfd6f 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.cc
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.cc
@@ -530,7 +530,7 @@ static void init_transport(grpc_chttp2_transport* t,
     t->keepalive_state = GRPC_CHTTP2_KEEPALIVE_STATE_WAITING;
     GRPC_CHTTP2_REF_TRANSPORT(t, "init keepalive ping");
     grpc_timer_init(&t->keepalive_ping_timer,
-                    ExecCtx::Get()->Now() + t->keepalive_time,
+                    grpc_core::ExecCtx::Get()->Now() + t->keepalive_time,
                     &t->init_keepalive_ping_locked);
   } else {
     /* Use GRPC_CHTTP2_KEEPALIVE_STATE_DISABLED to indicate there are no
@@ -2585,14 +2585,14 @@ static void init_keepalive_ping_locked(void* arg, grpc_error* error) {
     } else {
       GRPC_CHTTP2_REF_TRANSPORT(t, "init keepalive ping");
       grpc_timer_init(&t->keepalive_ping_timer,
-                      ExecCtx::Get()->Now() + t->keepalive_time,
+                      grpc_core::ExecCtx::Get()->Now() + t->keepalive_time,
                       &t->init_keepalive_ping_locked);
     }
   } else if (error == GRPC_ERROR_CANCELLED) {
     /* The keepalive ping timer may be cancelled by bdp */
     GRPC_CHTTP2_REF_TRANSPORT(t, "init keepalive ping");
     grpc_timer_init(&t->keepalive_ping_timer,
-                    ExecCtx::Get()->Now() + t->keepalive_time,
+                    grpc_core::ExecCtx::Get()->Now() + t->keepalive_time,
                     &t->init_keepalive_ping_locked);
   }
   GRPC_CHTTP2_UNREF_TRANSPORT(t, "init keepalive ping");
@@ -2602,7 +2602,7 @@ static void start_keepalive_ping_locked(void* arg, grpc_error* error) {
   grpc_chttp2_transport* t = (grpc_chttp2_transport*)arg;
   GRPC_CHTTP2_REF_TRANSPORT(t, "keepalive watchdog");
   grpc_timer_init(&t->keepalive_watchdog_timer,
-                  ExecCtx::Get()->Now() + t->keepalive_time,
+                  grpc_core::ExecCtx::Get()->Now() + t->keepalive_time,
                   &t->keepalive_watchdog_fired_locked);
 }
 
@@ -2614,7 +2614,7 @@ static void finish_keepalive_ping_locked(void* arg, grpc_error* error) {
       grpc_timer_cancel(&t->keepalive_watchdog_timer);
       GRPC_CHTTP2_REF_TRANSPORT(t, "init keepalive ping");
       grpc_timer_init(&t->keepalive_ping_timer,
-                      ExecCtx::Get()->Now() + t->keepalive_time,
+                      grpc_core::ExecCtx::Get()->Now() + t->keepalive_time,
                       &t->init_keepalive_ping_locked);
     }
   }
diff --git a/src/core/ext/transport/chttp2/transport/flow_control.cc b/src/core/ext/transport/chttp2/transport/flow_control.cc
index e54d59b5fa..14f089859e 100644
--- a/src/core/ext/transport/chttp2/transport/flow_control.cc
+++ b/src/core/ext/transport/chttp2/transport/flow_control.cc
@@ -160,7 +160,7 @@ TransportFlowControl::TransportFlowControl(const grpc_chttp2_transport* t,
                           .set_min_control_value(-1)
                           .set_max_control_value(25)
                           .set_integral_range(10)),
-      last_pid_update_(ExecCtx::Get()->Now()) {}
+      last_pid_update_(grpc_core::ExecCtx::Get()->Now()) {}
 
 uint32_t TransportFlowControl::MaybeSendUpdate(bool writing_anyway) {
   FlowControlTrace trace("t updt sent", this, nullptr);
@@ -306,7 +306,7 @@ double TransportFlowControl::TargetLogBdp() {
 }
 
 double TransportFlowControl::SmoothLogBdp(double value) {
-  grpc_millis now = ExecCtx::Get()->Now();
+  grpc_millis now = grpc_core::ExecCtx::Get()->Now();
   double bdp_error = value - pid_controller_.last_control_value();
   const double dt = (double)(now - last_pid_update_) * 1e-3;
   last_pid_update_ = now;
diff --git a/src/core/ext/transport/chttp2/transport/frame_ping.cc b/src/core/ext/transport/chttp2/transport/frame_ping.cc
index 60172be9cb..298a56721a 100644
--- a/src/core/ext/transport/chttp2/transport/frame_ping.cc
+++ b/src/core/ext/transport/chttp2/transport/frame_ping.cc
@@ -89,7 +89,7 @@ grpc_error* grpc_chttp2_ping_parser_parse(void* parser,
       grpc_chttp2_ack_ping(t, p->opaque_8bytes);
     } else {
       if (!t->is_client) {
-        grpc_millis now = ExecCtx::Get()->Now();
+        grpc_millis now = grpc_core::ExecCtx::Get()->Now();
         grpc_millis next_allowed_ping =
             t->ping_recv_state.last_ping_recv_time +
             t->ping_policy.min_recv_ping_interval_without_data;
diff --git a/src/core/ext/transport/chttp2/transport/hpack_encoder.cc b/src/core/ext/transport/chttp2/transport/hpack_encoder.cc
index efb6e54ce7..2f9849c09a 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_encoder.cc
+++ b/src/core/ext/transport/chttp2/transport/hpack_encoder.cc
@@ -570,7 +570,8 @@ static void deadline_enc(grpc_chttp2_hpack_compressor* c, grpc_millis deadline,
                          framer_state* st) {
   char timeout_str[GRPC_HTTP2_TIMEOUT_ENCODE_MIN_BUFSIZE];
   grpc_mdelem mdelem;
-  grpc_http2_encode_timeout(deadline - ExecCtx::Get()->Now(), timeout_str);
+  grpc_http2_encode_timeout(deadline - grpc_core::ExecCtx::Get()->Now(),
+                            timeout_str);
   mdelem = grpc_mdelem_from_slices(GRPC_MDSTR_GRPC_TIMEOUT,
                                    grpc_slice_from_copied_string(timeout_str));
   hpack_enc(c, mdelem, st);
diff --git a/src/core/ext/transport/chttp2/transport/parsing.cc b/src/core/ext/transport/chttp2/transport/parsing.cc
index f7f83c9aee..f73b498d40 100644
--- a/src/core/ext/transport/chttp2/transport/parsing.cc
+++ b/src/core/ext/transport/chttp2/transport/parsing.cc
@@ -436,7 +436,7 @@ static void on_initial_header(void* tp, grpc_mdelem md) {
     }
     if (timeout != GRPC_MILLIS_INF_FUTURE) {
       grpc_chttp2_incoming_metadata_buffer_set_deadline(
-          &s->metadata_buffer[0], ExecCtx::Get()->Now() + timeout);
+          &s->metadata_buffer[0], grpc_core::ExecCtx::Get()->Now() + timeout);
     }
     GRPC_MDELEM_UNREF(md);
   } else {
diff --git a/src/core/ext/transport/chttp2/transport/writing.cc b/src/core/ext/transport/chttp2/transport/writing.cc
index 4f76c2eb23..ddcac45d83 100644
--- a/src/core/ext/transport/chttp2/transport/writing.cc
+++ b/src/core/ext/transport/chttp2/transport/writing.cc
@@ -68,7 +68,7 @@ static void maybe_initiate_ping(grpc_chttp2_transport* t) {
     }
     return;
   }
-  grpc_millis now = ExecCtx::Get()->Now();
+  grpc_millis now = grpc_core::ExecCtx::Get()->Now();
   grpc_millis next_allowed_ping =
       t->ping_state.last_ping_sent_time +
       t->ping_policy.min_sent_ping_interval_without_data;
diff --git a/src/core/ext/transport/cronet/client/secure/cronet_channel_create.cc b/src/core/ext/transport/cronet/client/secure/cronet_channel_create.cc
index f634627f03..8e1dcc542e 100644
--- a/src/core/ext/transport/cronet/client/secure/cronet_channel_create.cc
+++ b/src/core/ext/transport/cronet/client/secure/cronet_channel_create.cc
@@ -49,6 +49,6 @@ GRPCAPI grpc_channel* grpc_cronet_secure_channel_create(
   grpc_transport* ct =
       grpc_create_cronet_transport(engine, target, args, reserved);
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   return grpc_channel_create(target, args, GRPC_CLIENT_DIRECT_CHANNEL, ct);
 }
diff --git a/src/core/ext/transport/cronet/transport/cronet_transport.cc b/src/core/ext/transport/cronet/transport/cronet_transport.cc
index 3411acc563..971071e387 100644
--- a/src/core/ext/transport/cronet/transport/cronet_transport.cc
+++ b/src/core/ext/transport/cronet/transport/cronet_transport.cc
@@ -398,7 +398,7 @@ static void execute_from_storage(stream_obj* s) {
 */
 static void on_failed(bidirectional_stream* stream, int net_error) {
   CRONET_LOG(GPR_DEBUG, "on_failed(%p, %d)", stream, net_error);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   stream_obj* s = (stream_obj*)stream->annotation;
   gpr_mu_lock(&s->mu);
@@ -424,7 +424,7 @@ static void on_failed(bidirectional_stream* stream, int net_error) {
 */
 static void on_canceled(bidirectional_stream* stream) {
   CRONET_LOG(GPR_DEBUG, "on_canceled(%p)", stream);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   stream_obj* s = (stream_obj*)stream->annotation;
   gpr_mu_lock(&s->mu);
@@ -450,7 +450,7 @@ static void on_canceled(bidirectional_stream* stream) {
 */
 static void on_succeeded(bidirectional_stream* stream) {
   CRONET_LOG(GPR_DEBUG, "on_succeeded(%p)", stream);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   stream_obj* s = (stream_obj*)stream->annotation;
   gpr_mu_lock(&s->mu);
@@ -468,7 +468,7 @@ static void on_succeeded(bidirectional_stream* stream) {
 */
 static void on_stream_ready(bidirectional_stream* stream) {
   CRONET_LOG(GPR_DEBUG, "W: on_stream_ready(%p)", stream);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   stream_obj* s = (stream_obj*)stream->annotation;
   grpc_cronet_transport* t = (grpc_cronet_transport*)s->curr_ct;
   gpr_mu_lock(&s->mu);
@@ -498,7 +498,7 @@ static void on_response_headers_received(
     bidirectional_stream* stream,
     const bidirectional_stream_header_array* headers,
     const char* negotiated_protocol) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   CRONET_LOG(GPR_DEBUG, "R: on_response_headers_received(%p, %p, %s)", stream,
              headers, negotiated_protocol);
   stream_obj* s = (stream_obj*)stream->annotation;
@@ -550,7 +550,7 @@ static void on_response_headers_received(
   Cronet callback
 */
 static void on_write_completed(bidirectional_stream* stream, const char* data) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   stream_obj* s = (stream_obj*)stream->annotation;
   CRONET_LOG(GPR_DEBUG, "W: on_write_completed(%p, %s)", stream, data);
   gpr_mu_lock(&s->mu);
@@ -568,7 +568,7 @@ static void on_write_completed(bidirectional_stream* stream, const char* data) {
 */
 static void on_read_completed(bidirectional_stream* stream, char* data,
                               int count) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   stream_obj* s = (stream_obj*)stream->annotation;
   CRONET_LOG(GPR_DEBUG, "R: on_read_completed(%p, %p, %d)", stream, data,
              count);
@@ -610,7 +610,7 @@ static void on_read_completed(bidirectional_stream* stream, char* data,
 static void on_response_trailers_received(
     bidirectional_stream* stream,
     const bidirectional_stream_header_array* trailers) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   CRONET_LOG(GPR_DEBUG, "R: on_response_trailers_received(%p,%p)", stream,
              trailers);
   stream_obj* s = (stream_obj*)stream->annotation;
diff --git a/src/core/ext/transport/inproc/inproc_transport.cc b/src/core/ext/transport/inproc/inproc_transport.cc
index a79b2b26b0..e303f5ac0d 100644
--- a/src/core/ext/transport/inproc/inproc_transport.cc
+++ b/src/core/ext/transport/inproc/inproc_transport.cc
@@ -1091,7 +1091,7 @@ static grpc_endpoint* get_endpoint(grpc_transport* t) { return NULL; }
 static void do_nothing(void* arg, grpc_error* error) {}
 
 void grpc_inproc_transport_init(void) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_CLOSURE_INIT(&do_nothing_closure, do_nothing, NULL,
                     grpc_schedule_on_exec_ctx);
   g_empty_slice = grpc_slice_from_static_buffer(NULL, 0);
@@ -1155,7 +1155,7 @@ grpc_channel* grpc_inproc_channel_create(grpc_server* server,
   GRPC_API_TRACE("grpc_inproc_channel_create(server=%p, args=%p)", 2,
                  (server, args));
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   const grpc_channel_args* server_args = grpc_server_get_channel_args(server);
 
@@ -1186,7 +1186,7 @@ grpc_channel* grpc_inproc_channel_create(grpc_server* server,
 }
 
 void grpc_inproc_transport_shutdown(void) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_slice_unref_internal(g_empty_slice);
   grpc_slice_unref_internal(g_fake_path_key);
   grpc_slice_unref_internal(g_fake_path_value);
diff --git a/src/core/lib/backoff/backoff.cc b/src/core/lib/backoff/backoff.cc
index b75ce79d46..da3b9b1b2d 100644
--- a/src/core/lib/backoff/backoff.cc
+++ b/src/core/lib/backoff/backoff.cc
@@ -36,7 +36,7 @@ grpc_backoff_result grpc_backoff_begin(grpc_backoff* backoff) {
   backoff->current_backoff = backoff->initial_backoff;
   const grpc_millis initial_timeout =
       GPR_MAX(backoff->initial_backoff, backoff->min_connect_timeout);
-  const grpc_millis now = ExecCtx::Get()->Now();
+  const grpc_millis now = grpc_core::ExecCtx::Get()->Now();
   const grpc_backoff_result result = {now + initial_timeout,
                                       now + backoff->current_backoff};
   return result;
@@ -67,7 +67,7 @@ grpc_backoff_result grpc_backoff_step(grpc_backoff* backoff) {
               backoff->min_connect_timeout);
   const grpc_millis next_timeout = GPR_MIN(
       (grpc_millis)(backoff->current_backoff + jitter), backoff->max_backoff);
-  const grpc_millis now = ExecCtx::Get()->Now();
+  const grpc_millis now = grpc_core::ExecCtx::Get()->Now();
   const grpc_backoff_result result = {now + current_timeout,
                                       now + next_timeout};
   return result;
diff --git a/src/core/lib/compression/stream_compression_gzip.cc b/src/core/lib/compression/stream_compression_gzip.cc
index 3fae3490ce..4aaef4e128 100644
--- a/src/core/lib/compression/stream_compression_gzip.cc
+++ b/src/core/lib/compression/stream_compression_gzip.cc
@@ -40,7 +40,7 @@ static bool gzip_flate(grpc_stream_compression_context_gzip* ctx,
   /* Full flush is not allowed when inflating. */
   GPR_ASSERT(!(ctx->flate == inflate && (flush == Z_FINISH)));
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   int r;
   bool eoc = false;
   size_t original_max_output_size = max_output_size;
diff --git a/src/core/lib/debug/stats.h b/src/core/lib/debug/stats.h
index 24b0084130..6b36f67172 100644
--- a/src/core/lib/debug/stats.h
+++ b/src/core/lib/debug/stats.h
@@ -35,7 +35,7 @@ typedef struct grpc_stats_data {
 extern grpc_stats_data* grpc_stats_per_cpu_storage;
 
 #define GRPC_THREAD_STATS_DATA() \
-  (&grpc_stats_per_cpu_storage[ExecCtx::Get()->starting_cpu()])
+  (&grpc_stats_per_cpu_storage[grpc_core::ExecCtx::Get()->starting_cpu()])
 
 #define GRPC_STATS_INC_COUNTER(ctr) \
   (gpr_atm_no_barrier_fetch_add(&GRPC_THREAD_STATS_DATA()->counters[(ctr)], 1))
diff --git a/src/core/lib/iomgr/block_annotate.h b/src/core/lib/iomgr/block_annotate.h
index 7783da0c14..55bde3eaac 100644
--- a/src/core/lib/iomgr/block_annotate.h
+++ b/src/core/lib/iomgr/block_annotate.h
@@ -41,18 +41,18 @@ void gpr_thd_end_blocking_region();
   do {                                        \
     gpr_thd_start_blocking_region();          \
   } while (0)
-#define GRPC_SCHEDULING_END_BLOCKING_REGION \
-  do {                                      \
-    gpr_thd_end_blocking_region();          \
-    ExecCtx::Get()->InvalidateNow();        \
+#define GRPC_SCHEDULING_END_BLOCKING_REGION     \
+  do {                                          \
+    gpr_thd_end_blocking_region();              \
+    grpc_core::ExecCtx::Get()->InvalidateNow(); \
   } while (0)
 #else
 #define GRPC_SCHEDULING_START_BLOCKING_REGION \
   do {                                        \
   } while (0)
-#define GRPC_SCHEDULING_END_BLOCKING_REGION \
-  do {                                      \
-    ExecCtx::Get()->InvalidateNow();        \
+#define GRPC_SCHEDULING_END_BLOCKING_REGION     \
+  do {                                          \
+    grpc_core::ExecCtx::Get()->InvalidateNow(); \
   } while (0)
 #endif
 
diff --git a/src/core/lib/iomgr/combiner.cc b/src/core/lib/iomgr/combiner.cc
index c9f5448630..6cc4eef1d8 100644
--- a/src/core/lib/iomgr/combiner.cc
+++ b/src/core/lib/iomgr/combiner.cc
@@ -129,23 +129,23 @@ grpc_combiner* grpc_combiner_ref(grpc_combiner* lock GRPC_COMBINER_DEBUG_ARGS) {
 
 static void push_last_on_exec_ctx(grpc_combiner* lock) {
   lock->next_combiner_on_this_exec_ctx = nullptr;
-  if (ExecCtx::Get()->combiner_data()->active_combiner == nullptr) {
-    ExecCtx::Get()->combiner_data()->active_combiner =
-        ExecCtx::Get()->combiner_data()->last_combiner = lock;
+  if (grpc_core::ExecCtx::Get()->combiner_data()->active_combiner == nullptr) {
+    grpc_core::ExecCtx::Get()->combiner_data()->active_combiner =
+        grpc_core::ExecCtx::Get()->combiner_data()->last_combiner = lock;
   } else {
-    ExecCtx::Get()
+    grpc_core::ExecCtx::Get()
         ->combiner_data()
         ->last_combiner->next_combiner_on_this_exec_ctx = lock;
-    ExecCtx::Get()->combiner_data()->last_combiner = lock;
+    grpc_core::ExecCtx::Get()->combiner_data()->last_combiner = lock;
   }
 }
 
 static void push_first_on_exec_ctx(grpc_combiner* lock) {
   lock->next_combiner_on_this_exec_ctx =
-      ExecCtx::Get()->combiner_data()->active_combiner;
-  ExecCtx::Get()->combiner_data()->active_combiner = lock;
+      grpc_core::ExecCtx::Get()->combiner_data()->active_combiner;
+  grpc_core::ExecCtx::Get()->combiner_data()->active_combiner = lock;
   if (lock->next_combiner_on_this_exec_ctx == NULL) {
-    ExecCtx::Get()->combiner_data()->last_combiner = lock;
+    grpc_core::ExecCtx::Get()->combiner_data()->last_combiner = lock;
   }
 }
 
@@ -165,7 +165,7 @@ static void combiner_exec(grpc_closure* cl, grpc_error* error) {
     GRPC_STATS_INC_COMBINER_LOCKS_INITIATED();
     GPR_TIMER_MARK("combiner.initiated", 0);
     gpr_atm_no_barrier_store(&lock->initiating_exec_ctx_or_null,
-                             (gpr_atm)ExecCtx::Get());
+                             (gpr_atm)grpc_core::ExecCtx::Get());
     // first element on this list: add it to the list of combiner locks
     // executing within this exec_ctx
     push_last_on_exec_ctx(lock);
@@ -174,7 +174,7 @@ static void combiner_exec(grpc_closure* cl, grpc_error* error) {
     // offload for one or two actions, and that's fine
     gpr_atm initiator =
         gpr_atm_no_barrier_load(&lock->initiating_exec_ctx_or_null);
-    if (initiator != 0 && initiator != (gpr_atm)ExecCtx::Get()) {
+    if (initiator != 0 && initiator != (gpr_atm)grpc_core::ExecCtx::Get()) {
       gpr_atm_no_barrier_store(&lock->initiating_exec_ctx_or_null, 0);
     }
   }
@@ -186,12 +186,12 @@ static void combiner_exec(grpc_closure* cl, grpc_error* error) {
 }
 
 static void move_next() {
-  ExecCtx::Get()->combiner_data()->active_combiner =
-      ExecCtx::Get()
+  grpc_core::ExecCtx::Get()->combiner_data()->active_combiner =
+      grpc_core::ExecCtx::Get()
           ->combiner_data()
           ->active_combiner->next_combiner_on_this_exec_ctx;
-  if (ExecCtx::Get()->combiner_data()->active_combiner == NULL) {
-    ExecCtx::Get()->combiner_data()->last_combiner = NULL;
+  if (grpc_core::ExecCtx::Get()->combiner_data()->active_combiner == NULL) {
+    grpc_core::ExecCtx::Get()->combiner_data()->last_combiner = NULL;
   }
 }
 
@@ -209,7 +209,8 @@ static void queue_offload(grpc_combiner* lock) {
 
 bool grpc_combiner_continue_exec_ctx() {
   GPR_TIMER_BEGIN("combiner.continue_exec_ctx", 0);
-  grpc_combiner* lock = ExecCtx::Get()->combiner_data()->active_combiner;
+  grpc_combiner* lock =
+      grpc_core::ExecCtx::Get()->combiner_data()->active_combiner;
   if (lock == NULL) {
     GPR_TIMER_END("combiner.continue_exec_ctx", 0);
     return false;
@@ -224,10 +225,10 @@ bool grpc_combiner_continue_exec_ctx() {
                               "exec_ctx_ready_to_finish=%d "
                               "time_to_execute_final_list=%d",
                               lock, contended,
-                              ExecCtx::Get()->IsReadyToFinish(),
+                              grpc_core::ExecCtx::Get()->IsReadyToFinish(),
                               lock->time_to_execute_final_list));
 
-  if (contended && ExecCtx::Get()->IsReadyToFinish() &&
+  if (contended && grpc_core::ExecCtx::Get()->IsReadyToFinish() &&
       grpc_executor_is_threaded()) {
     GPR_TIMER_MARK("offload_from_finished_exec_ctx", 0);
     // this execution context wants to move on: schedule remaining work to be
@@ -333,11 +334,11 @@ static void combiner_finally_exec(grpc_closure* closure, grpc_error* error) {
   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, ExecCtx::Get()->combiner_data()->active_combiner));
+  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 (ExecCtx::Get()->combiner_data()->active_combiner != lock) {
+  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)),
diff --git a/src/core/lib/iomgr/endpoint_pair_posix.cc b/src/core/lib/iomgr/endpoint_pair_posix.cc
index 1a281322a8..65db4a9675 100644
--- a/src/core/lib/iomgr/endpoint_pair_posix.cc
+++ b/src/core/lib/iomgr/endpoint_pair_posix.cc
@@ -54,7 +54,7 @@ grpc_endpoint_pair grpc_iomgr_create_endpoint_pair(const char* name,
   char* final_name;
   create_sockets(sv);
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   gpr_asprintf(&final_name, "%s:client", name);
   p.client = grpc_tcp_create(grpc_fd_create(sv[1], final_name), args,
diff --git a/src/core/lib/iomgr/endpoint_pair_windows.cc b/src/core/lib/iomgr/endpoint_pair_windows.cc
index e0f211cdf9..afd91c9932 100644
--- a/src/core/lib/iomgr/endpoint_pair_windows.cc
+++ b/src/core/lib/iomgr/endpoint_pair_windows.cc
@@ -72,7 +72,7 @@ grpc_endpoint_pair grpc_iomgr_create_endpoint_pair(
   SOCKET sv[2];
   grpc_endpoint_pair p;
   create_sockets(sv);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   p.client = grpc_tcp_create(grpc_winsocket_create(sv[1], "endpoint:client"),
                              channel_args, "endpoint:server");
   p.server = grpc_tcp_create(grpc_winsocket_create(sv[0], "endpoint:server"),
diff --git a/src/core/lib/iomgr/ev_epoll1_linux.cc b/src/core/lib/iomgr/ev_epoll1_linux.cc
index 2b486887b8..f22fb82797 100644
--- a/src/core/lib/iomgr/ev_epoll1_linux.cc
+++ b/src/core/lib/iomgr/ev_epoll1_linux.cc
@@ -554,7 +554,7 @@ static void pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure) {
 
 static int poll_deadline_to_millis_timeout(grpc_millis millis) {
   if (millis == GRPC_MILLIS_INF_FUTURE) return -1;
-  grpc_millis delta = millis - ExecCtx::Get()->Now();
+  grpc_millis delta = millis - grpc_core::ExecCtx::Get()->Now();
   if (delta > INT_MAX) {
     return INT_MAX;
   } else if (delta < 0) {
@@ -743,7 +743,7 @@ static bool begin_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
         SET_KICK_STATE(worker, KICKED);
       }
     }
-    ExecCtx::Get()->InvalidateNow();
+    grpc_core::ExecCtx::Get()->InvalidateNow();
   }
 
   if (GRPC_TRACER_ON(grpc_polling_trace)) {
@@ -848,7 +848,7 @@ static void end_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
   /* Make sure we appear kicked */
   SET_KICK_STATE(worker, KICKED);
   grpc_closure_list_move(&worker->schedule_on_end_work,
-                         ExecCtx::Get()->closure_list());
+                         grpc_core::ExecCtx::Get()->closure_list());
   if (gpr_atm_no_barrier_load(&g_active_poller) == (gpr_atm)worker) {
     if (worker->next != worker && worker->next->state == UNKICKED) {
       if (GRPC_TRACER_ON(grpc_polling_trace)) {
@@ -859,9 +859,9 @@ static void end_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
       SET_KICK_STATE(worker->next, DESIGNATED_POLLER);
       GRPC_STATS_INC_POLLSET_KICK_WAKEUP_CV();
       gpr_cv_signal(&worker->next->cv);
-      if (ExecCtx::Get()->HasWork()) {
+      if (grpc_core::ExecCtx::Get()->HasWork()) {
         gpr_mu_unlock(&pollset->mu);
-        ExecCtx::Get()->Flush();
+        grpc_core::ExecCtx::Get()->Flush();
         gpr_mu_lock(&pollset->mu);
       }
     } else {
@@ -892,12 +892,12 @@ static void end_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
         found_worker = check_neighborhood_for_available_poller(neighborhood);
         gpr_mu_unlock(&neighborhood->mu);
       }
-      ExecCtx::Get()->Flush();
+      grpc_core::ExecCtx::Get()->Flush();
       gpr_mu_lock(&pollset->mu);
     }
-  } else if (ExecCtx::Get()->HasWork()) {
+  } else if (grpc_core::ExecCtx::Get()->HasWork()) {
     gpr_mu_unlock(&pollset->mu);
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
     gpr_mu_lock(&pollset->mu);
   }
   if (worker->initialized_cv) {
@@ -948,8 +948,8 @@ static grpc_error* pollset_work(grpc_pollset* ps,
 
        process_epoll_events() returns very quickly: It just queues the work on
        exec_ctx but does not execute it (the actual exectution or more
-       accurately ExecCtx::Get()->Flush() happens in end_worker() AFTER
-       selecting a designated poller). So we are not waiting long periods
+       accurately grpc_core::ExecCtx::Get()->Flush() happens in end_worker()
+       AFTER selecting a designated poller). So we are not waiting long periods
        without a designated poller */
     if (gpr_atm_acq_load(&g_epoll_set.cursor) ==
         gpr_atm_acq_load(&g_epoll_set.num_events)) {
diff --git a/src/core/lib/iomgr/ev_epollex_linux.cc b/src/core/lib/iomgr/ev_epollex_linux.cc
index 385b5f68d0..5b4edd1e74 100644
--- a/src/core/lib/iomgr/ev_epollex_linux.cc
+++ b/src/core/lib/iomgr/ev_epollex_linux.cc
@@ -682,7 +682,7 @@ static void pollset_init(grpc_pollset* pollset, gpr_mu** mu) {
 
 static int poll_deadline_to_millis_timeout(grpc_millis millis) {
   if (millis == GRPC_MILLIS_INF_FUTURE) return -1;
-  grpc_millis delta = millis - ExecCtx::Get()->Now();
+  grpc_millis delta = millis - grpc_core::ExecCtx::Get()->Now();
   if (delta > INT_MAX)
     return INT_MAX;
   else if (delta < 0)
@@ -902,7 +902,7 @@ static bool begin_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
                 worker->pollable_obj, worker);
       }
     }
-    ExecCtx::Get()->InvalidateNow();
+    grpc_core::ExecCtx::Get()->InvalidateNow();
   } else {
     gpr_mu_unlock(&pollset->mu);
   }
@@ -970,8 +970,8 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
     gpr_log(GPR_DEBUG,
             "PS:%p work hdl=%p worker=%p now=%" PRIdPTR " deadline=%" PRIdPTR
             " kwp=%d pollable=%p",
-            pollset, worker_hdl, WORKER_PTR, ExecCtx::Get()->Now(), deadline,
-            pollset->kicked_without_poller, pollset->active_pollable);
+            pollset, worker_hdl, WORKER_PTR, grpc_core::ExecCtx::Get()->Now(),
+            deadline, pollset->kicked_without_poller, pollset->active_pollable);
   }
   static const char* err_desc = "pollset_work";
   grpc_error* error = GRPC_ERROR_NONE;
@@ -990,7 +990,7 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
           &error,
           pollable_process_events(pollset, WORKER_PTR->pollable_obj, false),
           err_desc);
-      ExecCtx::Get()->Flush();
+      grpc_core::ExecCtx::Get()->Flush();
       gpr_tls_set(&g_current_thread_pollset, 0);
       gpr_tls_set(&g_current_thread_worker, 0);
     }
diff --git a/src/core/lib/iomgr/ev_epollsig_linux.cc b/src/core/lib/iomgr/ev_epollsig_linux.cc
index a9b094a2fa..4ded7c0211 100644
--- a/src/core/lib/iomgr/ev_epollsig_linux.cc
+++ b/src/core/lib/iomgr/ev_epollsig_linux.cc
@@ -1090,7 +1090,7 @@ static void pollset_init(grpc_pollset* pollset, gpr_mu** mu) {
 
 static int poll_deadline_to_millis_timeout(grpc_millis millis) {
   if (millis == GRPC_MILLIS_INF_FUTURE) return -1;
-  grpc_millis delta = millis - ExecCtx::Get()->Now();
+  grpc_millis delta = millis - grpc_core::ExecCtx::Get()->Now();
   if (delta > INT_MAX)
     return INT_MAX;
   else if (delta < 0)
@@ -1350,7 +1350,7 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
 
     pollset_work_and_unlock(pollset, &worker, timeout_ms, &g_orig_sigmask,
                             &error);
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
 
     gpr_mu_lock(&pollset->po.mu);
 
@@ -1373,7 +1373,7 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
     finish_shutdown_locked(pollset);
 
     gpr_mu_unlock(&pollset->po.mu);
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
     gpr_mu_lock(&pollset->po.mu);
   }
 
diff --git a/src/core/lib/iomgr/ev_poll_posix.cc b/src/core/lib/iomgr/ev_poll_posix.cc
index cab4f7547c..b6546aa4b4 100644
--- a/src/core/lib/iomgr/ev_poll_posix.cc
+++ b/src/core/lib/iomgr/ev_poll_posix.cc
@@ -1040,7 +1040,7 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
      worker list, which means nobody could ask us to re-evaluate polling). */
   done:
     if (!locked) {
-      queued_work |= ExecCtx::Get()->Flush();
+      queued_work |= grpc_core::ExecCtx::Get()->Flush();
       gpr_mu_lock(&pollset->mu);
       locked = 1;
     }
@@ -1074,7 +1074,7 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
       pollset->called_shutdown = 1;
       gpr_mu_unlock(&pollset->mu);
       finish_shutdown(pollset);
-      ExecCtx::Get()->Flush();
+      grpc_core::ExecCtx::Get()->Flush();
       /* Continuing to access pollset here is safe -- it is the caller's
        * responsibility to not destroy when it has outstanding calls to
        * pollset_work.
@@ -1083,7 +1083,7 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
     } else if (!grpc_closure_list_empty(pollset->idle_jobs)) {
       GRPC_CLOSURE_LIST_SCHED(&pollset->idle_jobs);
       gpr_mu_unlock(&pollset->mu);
-      ExecCtx::Get()->Flush();
+      grpc_core::ExecCtx::Get()->Flush();
       gpr_mu_lock(&pollset->mu);
     }
   }
@@ -1110,7 +1110,7 @@ static void pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure) {
 static int poll_deadline_to_millis_timeout(grpc_millis deadline) {
   if (deadline == GRPC_MILLIS_INF_FUTURE) return -1;
   if (deadline == 0) return 0;
-  grpc_millis n = deadline - ExecCtx::Get()->Now();
+  grpc_millis n = deadline - grpc_core::ExecCtx::Get()->Now();
   if (n < 0) return 0;
   if (n > INT_MAX) return -1;
   return (int)n;
diff --git a/src/core/lib/iomgr/exec_ctx.cc b/src/core/lib/iomgr/exec_ctx.cc
index fe5a0e7e2d..de71c1cf9c 100644
--- a/src/core/lib/iomgr/exec_ctx.cc
+++ b/src/core/lib/iomgr/exec_ctx.cc
@@ -25,29 +25,6 @@
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/profiling/timers.h"
 
-thread_local ExecCtx* exec_ctx = nullptr;
-
-ExecCtx::ExecCtx() : flags_(GRPC_EXEC_CTX_FLAG_IS_FINISHED) { exec_ctx = this; }
-ExecCtx::ExecCtx(uintptr_t fl) : flags_(fl) { exec_ctx = this; }
-ExecCtx::~ExecCtx() {
-  GPR_ASSERT(exec_ctx == this);
-  flags_ |= GRPC_EXEC_CTX_FLAG_IS_FINISHED;
-  Flush();
-  exec_ctx = last_exec_ctx_;
-}
-
-bool ExecCtx::IsReadyToFinish() {
-  if ((flags_ & GRPC_EXEC_CTX_FLAG_IS_FINISHED) == 0) {
-    if (CheckReadyToFinish()) {
-      flags_ |= GRPC_EXEC_CTX_FLAG_IS_FINISHED;
-      return true;
-    }
-    return false;
-  } else {
-    return true;
-  }
-}
-
 void exec_ctx_run(grpc_closure* closure, grpc_error* error) {
 #ifndef NDEBUG
   closure->scheduled = false;
@@ -67,48 +44,16 @@ void exec_ctx_run(grpc_closure* closure, grpc_error* error) {
   GRPC_ERROR_UNREF(error);
 }
 
-bool ExecCtx::Flush() {
-  bool did_something = 0;
-  GPR_TIMER_BEGIN("grpc_exec_ctx_flush", 0);
-  for (;;) {
-    if (!grpc_closure_list_empty(closure_list_)) {
-      grpc_closure* c = closure_list_.head;
-      closure_list_.head = closure_list_.tail = NULL;
-      while (c != NULL) {
-        grpc_closure* next = c->next_data.next;
-        grpc_error* error = c->error_data.error;
-        did_something = true;
-        exec_ctx_run(c, error);
-        c = next;
-      }
-    } else if (!grpc_combiner_continue_exec_ctx()) {
-      break;
-    }
-  }
-  GPR_ASSERT(combiner_data_.active_combiner == nullptr);
-  GPR_TIMER_END("grpc_exec_ctx_flush", 0);
-  return did_something;
-}
-
-void exec_ctx_sched(grpc_closure* closure, grpc_error* error) {
-  grpc_closure_list_append(exec_ctx->closure_list(), closure, error);
-}
-
 static gpr_timespec
     g_start_time[GPR_TIMESPAN + 1];  // assumes GPR_TIMESPAN is the
                                      // last enum value in
                                      // gpr_clock_type
 
-void ExecCtx::GlobalInit(void) {
-  for (int i = 0; i < GPR_TIMESPAN; i++) {
-    g_start_time[i] = gpr_now((gpr_clock_type)i);
-  }
-  // allows uniform treatment in conversion functions
-  g_start_time[GPR_TIMESPAN] = gpr_time_0(GPR_TIMESPAN);
+void exec_ctx_sched(grpc_closure* closure, grpc_error* error) {
+  grpc_closure_list_append(grpc_core::ExecCtx::Get()->closure_list(), closure,
+                           error);
 }
 
-void ExecCtx::GlobalShutdown(void) {}
-
 static gpr_atm timespec_to_atm_round_down(gpr_timespec ts) {
   ts = gpr_time_sub(ts, g_start_time[ts.clock_type]);
   double x =
@@ -154,6 +99,47 @@ grpc_millis grpc_timespec_to_millis_round_up(gpr_timespec ts) {
   return timespec_to_atm_round_up(ts);
 }
 
+static const grpc_closure_scheduler_vtable exec_ctx_scheduler_vtable = {
+    exec_ctx_run, exec_ctx_sched, "exec_ctx"};
+static grpc_closure_scheduler exec_ctx_scheduler = {&exec_ctx_scheduler_vtable};
+grpc_closure_scheduler* grpc_schedule_on_exec_ctx = &exec_ctx_scheduler;
+
+namespace grpc_core {
+thread_local ExecCtx* ExecCtx::exec_ctx_ = nullptr;
+
+bool ExecCtx::Flush() {
+  bool did_something = 0;
+  GPR_TIMER_BEGIN("grpc_exec_ctx_flush", 0);
+  for (;;) {
+    if (!grpc_closure_list_empty(closure_list_)) {
+      grpc_closure* c = closure_list_.head;
+      closure_list_.head = closure_list_.tail = NULL;
+      while (c != NULL) {
+        grpc_closure* next = c->next_data.next;
+        grpc_error* error = c->error_data.error;
+        did_something = true;
+        exec_ctx_run(c, error);
+        c = next;
+      }
+    } else if (!grpc_combiner_continue_exec_ctx()) {
+      break;
+    }
+  }
+  GPR_ASSERT(combiner_data_.active_combiner == nullptr);
+  GPR_TIMER_END("grpc_exec_ctx_flush", 0);
+  return did_something;
+}
+
+void ExecCtx::GlobalInit(void) {
+  for (int i = 0; i < GPR_TIMESPAN; i++) {
+    g_start_time[i] = gpr_now((gpr_clock_type)i);
+  }
+  // allows uniform treatment in conversion functions
+  g_start_time[GPR_TIMESPAN] = gpr_time_0(GPR_TIMESPAN);
+}
+
+void ExecCtx::GlobalShutdown(void) {}
+
 grpc_millis ExecCtx::Now() {
   if (!now_is_valid_) {
     now_ = timespec_to_atm_round_down(gpr_now(GPR_CLOCK_MONOTONIC));
@@ -162,9 +148,4 @@ grpc_millis ExecCtx::Now() {
   return now_;
 }
 
-ExecCtx* ExecCtx::Get() { return exec_ctx; }
-
-static const grpc_closure_scheduler_vtable exec_ctx_scheduler_vtable = {
-    exec_ctx_run, exec_ctx_sched, "exec_ctx"};
-static grpc_closure_scheduler exec_ctx_scheduler = {&exec_ctx_scheduler_vtable};
-grpc_closure_scheduler* grpc_schedule_on_exec_ctx = &exec_ctx_scheduler;
+}  // namespace grpc_core
diff --git a/src/core/lib/iomgr/exec_ctx.h b/src/core/lib/iomgr/exec_ctx.h
index a71e43e178..7b8da2f0af 100644
--- a/src/core/lib/iomgr/exec_ctx.h
+++ b/src/core/lib/iomgr/exec_ctx.h
@@ -46,6 +46,7 @@ typedef struct grpc_combiner grpc_combiner;
    should be given to not delete said call/channel from this exec_ctx */
 #define GRPC_EXEC_CTX_FLAG_THREAD_RESOURCE_LOOP 2
 
+namespace grpc_core {
 /** Execution context.
  *  A bag of data that collects information along a callstack.
  *  Generally created at public API entry points, and passed down as
@@ -68,10 +69,25 @@ typedef struct grpc_combiner grpc_combiner;
  */
 class ExecCtx {
  public:
-  ExecCtx();
-  ExecCtx(uintptr_t fl);
-  ~ExecCtx();
+  /** Default Constructor */
+  ExecCtx() : flags_(GRPC_EXEC_CTX_FLAG_IS_FINISHED) { exec_ctx_ = this; }
+
+  /** Parameterised Constructor */
+  ExecCtx(uintptr_t fl) : flags_(fl) { exec_ctx_ = this; }
+
+  /** Destructor */
+  ~ExecCtx() {
+    GPR_ASSERT(exec_ctx_ == this);
+    flags_ |= GRPC_EXEC_CTX_FLAG_IS_FINISHED;
+    Flush();
+    exec_ctx_ = last_exec_ctx_;
+  }
+
+  /** Disallow copy and assignment operators */
+  ExecCtx(const ExecCtx&) = delete;
+  ExecCtx& operator=(const ExecCtx&) = delete;
 
+  /** Return starting_cpu */
   unsigned starting_cpu() const { return starting_cpu_; }
 
   struct CombinerData {
@@ -84,8 +100,13 @@ class ExecCtx {
   /** Only to be used by grpc-combiner code */
   CombinerData* combiner_data() { return &combiner_data_; }
 
+  /** Return pointer to grpc_closure_list */
   grpc_closure_list* closure_list() { return &closure_list_; }
 
+  /** Return flags */
+  uintptr_t flags() { return flags_; }
+
+  /** Checks if there is work to be done */
   bool HasWork() {
     return combiner_data_.active_combiner != NULL ||
            !grpc_closure_list_empty(closure_list_);
@@ -99,32 +120,59 @@ class ExecCtx {
   /** Returns true if we'd like to leave this execution context as soon as
 possible: useful for deciding whether to do something more or not depending
 on outside context */
-  bool IsReadyToFinish();
+  bool IsReadyToFinish() {
+    if ((flags_ & GRPC_EXEC_CTX_FLAG_IS_FINISHED) == 0) {
+      if (CheckReadyToFinish()) {
+        flags_ |= GRPC_EXEC_CTX_FLAG_IS_FINISHED;
+        return true;
+      }
+      return false;
+    } else {
+      return true;
+    }
+  }
 
+  /** Returns the stored current time relative to start if valid,
+   * otherwise refreshes the stored time, sets it valid and returns the new
+   * value */
   grpc_millis Now();
 
+  /** Invalidates the stored time value. A new time value will be set on calling
+   * Now() */
   void InvalidateNow() { now_is_valid_ = false; }
 
-  void SetNow(grpc_millis new_val) {
-    now_ = new_val;
+  /** To be used only by shutdown code in iomgr */
+  void SetNowIomgrShutdown() {
+    now_ = GRPC_MILLIS_INF_FUTURE;
     now_is_valid_ = true;
   }
 
-  uintptr_t flags() { return flags_; }
+  /** To be used only for testing.
+   * Sets the now value
+   */
+  void TestOnlySetNow(grpc_millis new_val) {
+    now_ = new_val;
+    now_is_valid_ = true;
+  }
 
   /** Finish any pending work for a grpc_exec_ctx. Must be called before
    *  the instance is destroyed, or work may be lost. */
   void Finish();
 
+  /** Global initialization for ExecCtx. Called by iomgr */
   static void GlobalInit(void);
 
+  /** Global shutdown for ExecCtx. Called by iomgr */
   static void GlobalShutdown(void);
 
-  static ExecCtx* Get();
+  /** Gets pointer to current exec_ctx */
+  static ExecCtx* Get() { return exec_ctx_; }
 
  protected:
+  /** Check if ready to finish */
   virtual bool CheckReadyToFinish() { return false; }
 
+ private:
   grpc_closure_list closure_list_ = GRPC_CLOSURE_LIST_INIT;
   CombinerData combiner_data_ = {nullptr, nullptr};
   uintptr_t flags_;
@@ -133,8 +181,10 @@ on outside context */
   bool now_is_valid_ = false;
   grpc_millis now_ = 0;
 
-  ExecCtx* last_exec_ctx_ = Get();
+  static thread_local ExecCtx* exec_ctx_;
+  ExecCtx* last_exec_ctx_ = exec_ctx_;
 };
+}  // namespace grpc_core
 
 extern grpc_closure_scheduler* grpc_schedule_on_exec_ctx;
 
diff --git a/src/core/lib/iomgr/executor.cc b/src/core/lib/iomgr/executor.cc
index bf8805a2cd..4db298c1c5 100644
--- a/src/core/lib/iomgr/executor.cc
+++ b/src/core/lib/iomgr/executor.cc
@@ -78,7 +78,7 @@ static size_t run_closures(grpc_closure_list list) {
     GRPC_ERROR_UNREF(error);
     c = next;
     n++;
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
   }
 
   return n;
@@ -145,7 +145,7 @@ static void executor_thread(void* arg) {
   thread_state* ts = (thread_state*)arg;
   gpr_tls_set(&g_this_thread_state, (intptr_t)ts);
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   size_t subtract_depth = 0;
   for (;;) {
@@ -175,7 +175,7 @@ static void executor_thread(void* arg) {
       gpr_log(GPR_DEBUG, "EXECUTOR[%d]: execute", (int)(ts - g_thread_state));
     }
 
-    ExecCtx::Get()->InvalidateNow();
+    grpc_core::ExecCtx::Get()->InvalidateNow();
     subtract_depth = run_closures(exec);
   }
 }
@@ -200,12 +200,14 @@ static void executor_push(grpc_closure* closure, grpc_error* error,
         gpr_log(GPR_DEBUG, "EXECUTOR: schedule %p inline", closure);
 #endif
       }
-      grpc_closure_list_append(ExecCtx::Get()->closure_list(), closure, error);
+      grpc_closure_list_append(grpc_core::ExecCtx::Get()->closure_list(),
+                               closure, error);
       return;
     }
     thread_state* ts = (thread_state*)gpr_tls_get(&g_this_thread_state);
     if (ts == NULL) {
-      ts = &g_thread_state[GPR_HASH_POINTER(ExecCtx::Get(), cur_thread_count)];
+      ts = &g_thread_state[GPR_HASH_POINTER(grpc_core::ExecCtx::Get(),
+                                            cur_thread_count)];
     } else {
       GRPC_STATS_INC_EXECUTOR_SCHEDULED_TO_SELF();
     }
diff --git a/src/core/lib/iomgr/iocp_windows.cc b/src/core/lib/iomgr/iocp_windows.cc
index 1686bf2872..f5c6297438 100644
--- a/src/core/lib/iomgr/iocp_windows.cc
+++ b/src/core/lib/iomgr/iocp_windows.cc
@@ -46,7 +46,7 @@ static DWORD deadline_to_millis_timeout(grpc_millis deadline) {
   if (deadline == GRPC_MILLIS_INF_FUTURE) {
     return INFINITE;
   }
-  grpc_millis now = ExecCtx::Get()->Now();
+  grpc_millis now = grpc_core::ExecCtx::Get()->Now();
   if (deadline < now) return 0;
   grpc_millis timeout = deadline - now;
   if (timeout > std::numeric_limits<DWORD>::max()) return INFINITE;
@@ -65,7 +65,7 @@ grpc_iocp_work_status grpc_iocp_work(grpc_millis deadline) {
   success =
       GetQueuedCompletionStatus(g_iocp, &bytes, &completion_key, &overlapped,
                                 deadline_to_millis_timeout(deadline));
-  ExecCtx::Get()->InvalidateNow();
+  grpc_core::ExecCtx::Get()->InvalidateNow();
   if (success == 0 && overlapped == NULL) {
     return GRPC_IOCP_WORK_TIMEOUT;
   }
@@ -113,19 +113,20 @@ void grpc_iocp_kick(void) {
 }
 
 void grpc_iocp_flush(void) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_iocp_work_status work_status;
 
   do {
     work_status = grpc_iocp_work(GRPC_MILLIS_INF_PAST);
-  } while (work_status == GRPC_IOCP_WORK_KICK || ExecCtx::Get()->Flush());
+  } while (work_status == GRPC_IOCP_WORK_KICK ||
+           grpc_core::ExecCtx::Get()->Flush());
 }
 
 void grpc_iocp_shutdown(void) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   while (gpr_atm_acq_load(&g_custom_events)) {
     grpc_iocp_work(GRPC_MILLIS_INF_FUTURE);
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
   }
 
   GPR_ASSERT(CloseHandle(g_iocp));
diff --git a/src/core/lib/iomgr/iomgr.cc b/src/core/lib/iomgr/iomgr.cc
index a1add4a303..9c74b5d1c3 100644
--- a/src/core/lib/iomgr/iomgr.cc
+++ b/src/core/lib/iomgr/iomgr.cc
@@ -49,7 +49,7 @@ void grpc_iomgr_init() {
   g_shutdown = 0;
   gpr_mu_init(&g_mu);
   gpr_cv_init(&g_rcv);
-  ExecCtx::GlobalInit();
+  grpc_core::ExecCtx::GlobalInit();
   grpc_executor_init();
   grpc_timer_list_init();
   g_root_object.next = g_root_object.prev = &g_root_object;
@@ -98,10 +98,10 @@ void grpc_iomgr_shutdown() {
       }
       last_warning_time = gpr_now(GPR_CLOCK_REALTIME);
     }
-    ExecCtx::Get()->SetNow(GRPC_MILLIS_INF_FUTURE);
+    grpc_core::ExecCtx::Get()->SetNowIomgrShutdown();
     if (grpc_timer_check(NULL) == GRPC_TIMERS_FIRED) {
       gpr_mu_unlock(&g_mu);
-      ExecCtx::Get()->Flush();
+      grpc_core::ExecCtx::Get()->Flush();
       grpc_iomgr_platform_flush();
       gpr_mu_lock(&g_mu);
       continue;
@@ -136,14 +136,14 @@ void grpc_iomgr_shutdown() {
   gpr_mu_unlock(&g_mu);
 
   grpc_timer_list_shutdown();
-  ExecCtx::Get()->Flush();
+  grpc_core::ExecCtx::Get()->Flush();
 
   /* ensure all threads have left g_mu */
   gpr_mu_lock(&g_mu);
   gpr_mu_unlock(&g_mu);
 
   grpc_iomgr_platform_shutdown();
-  ExecCtx::GlobalShutdown();
+  grpc_core::ExecCtx::GlobalShutdown();
   grpc_network_status_shutdown();
   gpr_mu_destroy(&g_mu);
   gpr_cv_destroy(&g_rcv);
diff --git a/src/core/lib/iomgr/iomgr_uv.cc b/src/core/lib/iomgr/iomgr_uv.cc
index 2ab414252a..5823bb7ec2 100644
--- a/src/core/lib/iomgr/iomgr_uv.cc
+++ b/src/core/lib/iomgr/iomgr_uv.cc
@@ -29,7 +29,7 @@
 gpr_thd_id g_init_thread;
 
 void grpc_iomgr_platform_init(void) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_pollset_global_init();
   grpc_register_tracer(&grpc_tcp_trace);
   grpc_executor_set_threading(false);
diff --git a/src/core/lib/iomgr/pollset_uv.cc b/src/core/lib/iomgr/pollset_uv.cc
index a68ad4a6e3..89d28a0f9d 100644
--- a/src/core/lib/iomgr/pollset_uv.cc
+++ b/src/core/lib/iomgr/pollset_uv.cc
@@ -124,7 +124,7 @@ grpc_error* grpc_pollset_work(grpc_pollset* pollset,
   GRPC_UV_ASSERT_SAME_THREAD();
   gpr_mu_unlock(&grpc_polling_mu);
   if (grpc_pollset_work_run_loop) {
-    grpc_millis now = ExecCtx::Get()->Now();
+    grpc_millis now = grpc_core::ExecCtx::Get()->Now();
     if (deadline >= now) {
       timeout = deadline - now;
     } else {
@@ -143,7 +143,7 @@ grpc_error* grpc_pollset_work(grpc_pollset* pollset,
     }
   }
   if (!grpc_closure_list_empty(exec_ctx->closure_list)) {
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
   }
   gpr_mu_lock(&grpc_polling_mu);
   return GRPC_ERROR_NONE;
diff --git a/src/core/lib/iomgr/pollset_windows.cc b/src/core/lib/iomgr/pollset_windows.cc
index 5ff3e7cb3a..81e1d009ca 100644
--- a/src/core/lib/iomgr/pollset_windows.cc
+++ b/src/core/lib/iomgr/pollset_windows.cc
@@ -129,7 +129,7 @@ grpc_error* grpc_pollset_work(grpc_pollset* pollset,
       g_active_poller = &worker;
       gpr_mu_unlock(&grpc_polling_mu);
       grpc_iocp_work(deadline);
-      ExecCtx::Get()->Flush();
+      grpc_core::ExecCtx::Get()->Flush();
       gpr_mu_lock(&grpc_polling_mu);
       pollset->is_iocp_worker = 0;
       g_active_poller = NULL;
@@ -160,10 +160,10 @@ grpc_error* grpc_pollset_work(grpc_pollset* pollset,
     while (!worker.kicked) {
       if (gpr_cv_wait(&worker.cv, &grpc_polling_mu,
                       grpc_millis_to_timespec(deadline, GPR_CLOCK_REALTIME))) {
-        ExecCtx::Get()->InvalidateNow();
+        grpc_core::ExecCtx::Get()->InvalidateNow();
         break;
       }
-      ExecCtx::Get()->InvalidateNow();
+      grpc_core::ExecCtx::Get()->InvalidateNow();
     }
   } else {
     pollset->kicked_without_pollers = 0;
@@ -171,7 +171,7 @@ grpc_error* grpc_pollset_work(grpc_pollset* pollset,
 done:
   if (!grpc_closure_list_empty(exec_ctx->closure_list)) {
     gpr_mu_unlock(&grpc_polling_mu);
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
     gpr_mu_lock(&grpc_polling_mu);
   }
   if (added_worker) {
diff --git a/src/core/lib/iomgr/resolve_address_uv.cc b/src/core/lib/iomgr/resolve_address_uv.cc
index ffd70c4f35..54adf9b9f6 100644
--- a/src/core/lib/iomgr/resolve_address_uv.cc
+++ b/src/core/lib/iomgr/resolve_address_uv.cc
@@ -114,7 +114,7 @@ static grpc_error* handle_addrinfo_result(int status, struct addrinfo* result,
 static void getaddrinfo_callback(uv_getaddrinfo_t* req, int status,
                                  struct addrinfo* res) {
   request* r = (request*)req->data;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_error* error;
   int retry_status;
   char* port = r->port;
diff --git a/src/core/lib/iomgr/resource_quota.cc b/src/core/lib/iomgr/resource_quota.cc
index 8fee585f4b..11cb5ddbee 100644
--- a/src/core/lib/iomgr/resource_quota.cc
+++ b/src/core/lib/iomgr/resource_quota.cc
@@ -622,7 +622,7 @@ void grpc_resource_quota_unref_internal(grpc_resource_quota* resource_quota) {
 
 /* Public API */
 void grpc_resource_quota_unref(grpc_resource_quota* resource_quota) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_resource_quota_unref_internal(resource_quota);
 }
 
@@ -647,7 +647,7 @@ double grpc_resource_quota_get_memory_pressure(
 /* Public API */
 void grpc_resource_quota_resize(grpc_resource_quota* resource_quota,
                                 size_t size) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   rq_resize_args* a = (rq_resize_args*)gpr_malloc(sizeof(*a));
   a->resource_quota = grpc_resource_quota_ref_internal(resource_quota);
   a->size = (int64_t)size;
diff --git a/src/core/lib/iomgr/tcp_client_uv.cc b/src/core/lib/iomgr/tcp_client_uv.cc
index 7454b01445..0bf3a043df 100644
--- a/src/core/lib/iomgr/tcp_client_uv.cc
+++ b/src/core/lib/iomgr/tcp_client_uv.cc
@@ -76,7 +76,7 @@ static void uv_tc_on_alarm(void* acp, grpc_error* error) {
 
 static void uv_tc_on_connect(uv_connect_t* req, int status) {
   grpc_uv_tcp_connect* connect = (grpc_uv_tcp_connect*)req->data;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_error* error = GRPC_ERROR_NONE;
   int done;
   grpc_closure* closure = connect->closure;
@@ -105,7 +105,7 @@ static void uv_tc_on_connect(uv_connect_t* req, int status) {
   }
   done = (--connect->refs == 0);
   if (done) {
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
     uv_tcp_connect_cleanup(connect);
   }
   GRPC_CLOSURE_SCHED(closure, error);
diff --git a/src/core/lib/iomgr/tcp_posix.cc b/src/core/lib/iomgr/tcp_posix.cc
index de3dabd7fc..04d4440f9e 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 = ExecCtx::Get()->Now() + 13 * GPR_MS_PER_SEC;
+  grpc_millis deadline = grpc_core::ExecCtx::Get()->Now() + 13 * GPR_MS_PER_SEC;
   GRPC_STATS_INC_TCP_BACKUP_POLLER_POLLS();
   GRPC_LOG_IF_ERROR(
       "backup_poller:pollset_work",
diff --git a/src/core/lib/iomgr/tcp_server_uv.cc b/src/core/lib/iomgr/tcp_server_uv.cc
index 9db2cbe58d..daa7afe95f 100644
--- a/src/core/lib/iomgr/tcp_server_uv.cc
+++ b/src/core/lib/iomgr/tcp_server_uv.cc
@@ -137,7 +137,7 @@ static void finish_shutdown(grpc_tcp_server* s) {
 
 static void handle_close_callback(uv_handle_t* handle) {
   grpc_tcp_listener* sp = (grpc_tcp_listener*)handle->data;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   sp->server->open_ports--;
   if (sp->server->open_ports == 0 && sp->server->shutdown) {
     finish_shutdown(sp->server);
@@ -174,9 +174,9 @@ void grpc_tcp_server_unref(grpc_tcp_server* s) {
   GRPC_UV_ASSERT_SAME_THREAD();
   if (gpr_unref(&s->refs)) {
     /* Complete shutdown_starting work before destroying. */
-    ExecCtx _local_exec_ctx;
+    grpc_core::ExecCtx _local_exec_ctx;
     GRPC_CLOSURE_LIST_SCHED(&s->shutdown_starting);
-    ExecCtx::Get()->Flush();
+    grpc_core::ExecCtx::Get()->Flush();
     tcp_server_destroy(s);
   }
 }
@@ -223,7 +223,7 @@ static void finish_accept(grpc_tcp_listener* sp) {
 
 static void on_connect(uv_stream_t* server, int status) {
   grpc_tcp_listener* sp = (grpc_tcp_listener*)server->data;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   if (status < 0) {
     switch (status) {
diff --git a/src/core/lib/iomgr/tcp_uv.cc b/src/core/lib/iomgr/tcp_uv.cc
index 3ea9674840..742ab9a754 100644
--- a/src/core/lib/iomgr/tcp_uv.cc
+++ b/src/core/lib/iomgr/tcp_uv.cc
@@ -112,7 +112,7 @@ static void tcp_ref(grpc_tcp* tcp) { gpr_ref(&tcp->refcount); }
 #endif
 
 static void uv_close_callback(uv_handle_t* handle) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_tcp* tcp = (grpc_tcp*)handle->data;
   TCP_UNREF(tcp, "destroy");
 }
@@ -124,7 +124,7 @@ static grpc_slice alloc_read_slice(grpc_resource_user* resource_user) {
 
 static void alloc_uv_buf(uv_handle_t* handle, size_t suggested_size,
                          uv_buf_t* buf) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_tcp* tcp = (grpc_tcp*)handle->data;
   (void)suggested_size;
   buf->base = (char*)GRPC_SLICE_START_PTR(tcp->read_slice);
@@ -135,7 +135,7 @@ static void read_callback(uv_stream_t* stream, ssize_t nread,
                           const uv_buf_t* buf) {
   grpc_slice sub;
   grpc_error* error;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_tcp* tcp = (grpc_tcp*)stream->data;
   grpc_closure* cb = tcp->read_cb;
   if (nread == 0) {
@@ -204,7 +204,7 @@ static void uv_endpoint_read(grpc_endpoint* ep, grpc_slice_buffer* read_slices,
 static void write_callback(uv_write_t* req, int status) {
   grpc_tcp* tcp = (grpc_tcp*)req->data;
   grpc_error* error;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_closure* cb = tcp->write_cb;
   tcp->write_cb = NULL;
   TCP_UNREF(tcp, "write");
@@ -355,7 +355,7 @@ grpc_endpoint* grpc_tcp_create(uv_tcp_t* handle,
                                grpc_resource_quota* resource_quota,
                                char* peer_string) {
   grpc_tcp* tcp = (grpc_tcp*)gpr_malloc(sizeof(grpc_tcp));
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   if (GRPC_TRACER_ON(grpc_tcp_trace)) {
     gpr_log(GPR_DEBUG, "Creating TCP endpoint %p", tcp);
diff --git a/src/core/lib/iomgr/timer_generic.cc b/src/core/lib/iomgr/timer_generic.cc
index d5e6066f35..ae82701676 100644
--- a/src/core/lib/iomgr/timer_generic.cc
+++ b/src/core/lib/iomgr/timer_generic.cc
@@ -249,7 +249,7 @@ void grpc_timer_list_init() {
   g_shared_mutables.initialized = true;
   g_shared_mutables.checker_mu = GPR_SPINLOCK_INITIALIZER;
   gpr_mu_init(&g_shared_mutables.mu);
-  g_shared_mutables.min_timer = ExecCtx::Get()->Now();
+  g_shared_mutables.min_timer = grpc_core::ExecCtx::Get()->Now();
   gpr_tls_init(&g_last_seen_min_timer);
   gpr_tls_set(&g_last_seen_min_timer, 0);
   grpc_register_tracer(&grpc_timer_trace);
@@ -341,7 +341,7 @@ void grpc_timer_init(grpc_timer* timer, grpc_millis deadline,
   if (GRPC_TRACER_ON(grpc_timer_trace)) {
     gpr_log(GPR_DEBUG,
             "TIMER %p: SET %" PRIdPTR " now %" PRIdPTR " call %p[%p]", timer,
-            deadline, ExecCtx::Get()->Now(), closure, closure->cb);
+            deadline, grpc_core::ExecCtx::Get()->Now(), closure, closure->cb);
   }
 
   if (!g_shared_mutables.initialized) {
@@ -354,7 +354,7 @@ void grpc_timer_init(grpc_timer* timer, grpc_millis deadline,
 
   gpr_mu_lock(&shard->mu);
   timer->pending = true;
-  grpc_millis now = ExecCtx::Get()->Now();
+  grpc_millis now = grpc_core::ExecCtx::Get()->Now();
   if (deadline <= now) {
     timer->pending = false;
     GRPC_CLOSURE_SCHED(timer->closure, GRPC_ERROR_NONE);
@@ -607,7 +607,7 @@ static grpc_timer_check_result run_some_expired_timers(gpr_atm now,
 
 grpc_timer_check_result grpc_timer_check(grpc_millis* next) {
   // prelude
-  grpc_millis now = ExecCtx::Get()->Now();
+  grpc_millis now = grpc_core::ExecCtx::Get()->Now();
 
   /* fetch from a thread-local first: this avoids contention on a globally
      mutable cacheline in the common case */
diff --git a/src/core/lib/iomgr/timer_manager.cc b/src/core/lib/iomgr/timer_manager.cc
index 69adb673d8..6a43f4fadb 100644
--- a/src/core/lib/iomgr/timer_manager.cc
+++ b/src/core/lib/iomgr/timer_manager.cc
@@ -98,7 +98,7 @@ static void start_timer_thread_and_unlock(void) {
 }
 
 void grpc_timer_manager_tick() {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_millis next = GRPC_MILLIS_INF_FUTURE;
   grpc_timer_check(&next);
 }
@@ -125,7 +125,7 @@ static void run_some_timers() {
   if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
     gpr_log(GPR_DEBUG, "flush exec_ctx");
   }
-  ExecCtx::Get()->Flush();
+  grpc_core::ExecCtx::Get()->Flush();
   gpr_mu_lock(&g_mu);
   // garbage collect any threads hanging out that are dead
   gc_completed_threads();
@@ -178,7 +178,7 @@ static bool wait_until(grpc_millis next) {
         g_timed_waiter_deadline = next;
 
         if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
-          grpc_millis wait_time = next - ExecCtx::Get()->Now();
+          grpc_millis wait_time = next - grpc_core::ExecCtx::Get()->Now();
           gpr_log(GPR_DEBUG, "sleep for a %" PRIdPTR " milliseconds",
                   wait_time);
         }
@@ -223,7 +223,7 @@ static bool wait_until(grpc_millis next) {
 static void timer_main_loop() {
   for (;;) {
     grpc_millis next = GRPC_MILLIS_INF_FUTURE;
-    ExecCtx::Get()->InvalidateNow();
+    grpc_core::ExecCtx::Get()->InvalidateNow();
     // check timer state, updates next to the next time to run a check
     switch (grpc_timer_check(&next)) {
       case GRPC_TIMERS_FIRED:
@@ -273,7 +273,7 @@ static void timer_thread_cleanup(completed_thread* ct) {
 static void timer_thread(void* completed_thread_ptr) {
   // this threads exec_ctx: we try to run things through to completion here
   // since it's easy to spin up new threads
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   timer_main_loop();
 
   timer_thread_cleanup((completed_thread*)completed_thread_ptr);
diff --git a/src/core/lib/iomgr/timer_uv.cc b/src/core/lib/iomgr/timer_uv.cc
index 6edd4169f1..1432eba51e 100644
--- a/src/core/lib/iomgr/timer_uv.cc
+++ b/src/core/lib/iomgr/timer_uv.cc
@@ -45,7 +45,7 @@ static void stop_uv_timer(uv_timer_t* handle) {
 
 void run_expired_timer(uv_timer_t* handle) {
   grpc_timer* timer = (grpc_timer*)handle->data;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_UV_ASSERT_SAME_THREAD();
   GPR_ASSERT(timer->pending);
   timer->pending = 0;
@@ -59,13 +59,13 @@ void grpc_timer_init(grpc_timer* timer, grpc_millis deadline,
   uv_timer_t* uv_timer;
   GRPC_UV_ASSERT_SAME_THREAD();
   timer->closure = closure;
-  if (deadline <= ExecCtx::Get()->Now()) {
+  if (deadline <= grpc_core::ExecCtx::Get()->Now()) {
     timer->pending = 0;
     GRPC_CLOSURE_SCHED(timer->closure, GRPC_ERROR_NONE);
     return;
   }
   timer->pending = 1;
-  timeout = (uint64_t)(deadline - ExecCtx::Get()->Now());
+  timeout = (uint64_t)(deadline - grpc_core::ExecCtx::Get()->Now());
   uv_timer = (uv_timer_t*)gpr_malloc(sizeof(uv_timer_t));
   uv_timer_init(uv_default_loop(), uv_timer);
   uv_timer->data = timer;
diff --git a/src/core/lib/security/context/security_context.cc b/src/core/lib/security/context/security_context.cc
index 9b58b3657f..570db78882 100644
--- a/src/core/lib/security/context/security_context.cc
+++ b/src/core/lib/security/context/security_context.cc
@@ -38,7 +38,7 @@ grpc_tracer_flag grpc_trace_auth_context_refcount =
 
 grpc_call_error grpc_call_set_credentials(grpc_call* call,
                                           grpc_call_credentials* creds) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_client_security_context* ctx = NULL;
   GRPC_API_TRACE("grpc_call_set_credentials(call=%p, creds=%p)", 2,
                  (call, creds));
@@ -87,7 +87,7 @@ grpc_client_security_context* grpc_client_security_context_create(void) {
 }
 
 void grpc_client_security_context_destroy(void* ctx) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_client_security_context* c = (grpc_client_security_context*)ctx;
   grpc_call_credentials_unref(c->creds);
   GRPC_AUTH_CONTEXT_UNREF(c->auth_context, "client_security_context");
diff --git a/src/core/lib/security/credentials/credentials.cc b/src/core/lib/security/credentials/credentials.cc
index 6a272653f8..5181f7f260 100644
--- a/src/core/lib/security/credentials/credentials.cc
+++ b/src/core/lib/security/credentials/credentials.cc
@@ -72,7 +72,7 @@ void grpc_channel_credentials_unref(grpc_channel_credentials* creds) {
 
 void grpc_channel_credentials_release(grpc_channel_credentials* creds) {
   GRPC_API_TRACE("grpc_channel_credentials_release(creds=%p)", 1, (creds));
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_channel_credentials_unref(creds);
 }
 
@@ -94,7 +94,7 @@ void grpc_call_credentials_unref(grpc_call_credentials* creds) {
 
 void grpc_call_credentials_release(grpc_call_credentials* creds) {
   GRPC_API_TRACE("grpc_call_credentials_release(creds=%p)", 1, (creds));
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_call_credentials_unref(creds);
 }
 
@@ -209,7 +209,7 @@ void grpc_server_credentials_unref(grpc_server_credentials* creds) {
 
 void grpc_server_credentials_release(grpc_server_credentials* creds) {
   GRPC_API_TRACE("grpc_server_credentials_release(creds=%p)", 1, (creds));
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_server_credentials_unref(creds);
 }
 
diff --git a/src/core/lib/security/credentials/google_default/google_default_credentials.cc b/src/core/lib/security/credentials/google_default/google_default_credentials.cc
index 03ec4bc3b3..a8991943b0 100644
--- a/src/core/lib/security/credentials/google_default/google_default_credentials.cc
+++ b/src/core/lib/security/credentials/google_default/google_default_credentials.cc
@@ -114,13 +114,13 @@ static int is_stack_running_on_compute_engine() {
       grpc_resource_quota_create("google_default_credentials");
   grpc_httpcli_get(
       &context, &detector.pollent, resource_quota, &request,
-      ExecCtx::Get()->Now() + max_detection_delay,
+      grpc_core::ExecCtx::Get()->Now() + max_detection_delay,
       GRPC_CLOSURE_CREATE(on_compute_engine_detection_http_response, &detector,
                           grpc_schedule_on_exec_ctx),
       &detector.response);
   grpc_resource_quota_unref_internal(resource_quota);
 
-  ExecCtx::Get()->Flush();
+  grpc_core::ExecCtx::Get()->Flush();
 
   /* Block until we get the response. This is not ideal but this should only be
      called once for the lifetime of the process by the default credentials. */
@@ -144,7 +144,7 @@ static int is_stack_running_on_compute_engine() {
   grpc_pollset_shutdown(grpc_polling_entity_pollset(&detector.pollent),
                         &destroy_closure);
   g_polling_mu = NULL;
-  ExecCtx::Get()->Flush();
+  grpc_core::ExecCtx::Get()->Flush();
 
   gpr_free(grpc_polling_entity_pollset(&detector.pollent));
   grpc_http_response_destroy(&detector.response);
@@ -220,7 +220,7 @@ grpc_channel_credentials* grpc_google_default_credentials_create(void) {
   grpc_error* error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
       "Failed to create Google credentials");
   grpc_error* err;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   GRPC_API_TRACE("grpc_google_default_credentials_create(void)", 0, ());
 
@@ -290,7 +290,7 @@ end:
 }
 
 void grpc_flush_cached_google_default_credentials(void) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   gpr_once_init(&g_once, init_default_credentials);
   gpr_mu_lock(&g_state_mu);
   if (default_credentials != NULL) {
diff --git a/src/core/lib/security/credentials/iam/iam_credentials.cc b/src/core/lib/security/credentials/iam/iam_credentials.cc
index 4d9da0cbe3..9f3a86877b 100644
--- a/src/core/lib/security/credentials/iam/iam_credentials.cc
+++ b/src/core/lib/security/credentials/iam/iam_credentials.cc
@@ -54,7 +54,7 @@ static grpc_call_credentials_vtable iam_vtable = {
 
 grpc_call_credentials* grpc_google_iam_credentials_create(
     const char* token, const char* authority_selector, void* reserved) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_API_TRACE(
       "grpc_iam_credentials_create(token=%s, authority_selector=%s, "
       "reserved=%p)",
diff --git a/src/core/lib/security/credentials/jwt/jwt_credentials.cc b/src/core/lib/security/credentials/jwt/jwt_credentials.cc
index ccc3f4aeed..3facce1798 100644
--- a/src/core/lib/security/credentials/jwt/jwt_credentials.cc
+++ b/src/core/lib/security/credentials/jwt/jwt_credentials.cc
@@ -181,7 +181,7 @@ grpc_call_credentials* grpc_service_account_jwt_access_credentials_create(
     gpr_free(clean_json);
   }
   GPR_ASSERT(reserved == NULL);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_call_credentials* creds =
       grpc_service_account_jwt_access_credentials_create_from_auth_json_key(
           grpc_auth_json_key_create_from_string(json_key), token_lifetime);
diff --git a/src/core/lib/security/credentials/jwt/jwt_verifier.cc b/src/core/lib/security/credentials/jwt/jwt_verifier.cc
index 5246e1f985..dd0d206b01 100644
--- a/src/core/lib/security/credentials/jwt/jwt_verifier.cc
+++ b/src/core/lib/security/credentials/jwt/jwt_verifier.cc
@@ -347,7 +347,7 @@ static verifier_cb_ctx* verifier_cb_ctx_create(
     grpc_jwt_claims* claims, const char* audience, grpc_slice signature,
     const char* signed_jwt, size_t signed_jwt_len, void* user_data,
     grpc_jwt_verification_done_cb cb) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   verifier_cb_ctx* ctx = (verifier_cb_ctx*)gpr_zalloc(sizeof(verifier_cb_ctx));
   ctx->verifier = verifier;
   ctx->pollent = grpc_polling_entity_create_from_pollset(pollset);
@@ -702,7 +702,7 @@ static void on_openid_config_retrieved(void* user_data, grpc_error* error) {
   resource_quota = grpc_resource_quota_create("jwt_verifier");
   grpc_httpcli_get(
       &ctx->verifier->http_ctx, &ctx->pollent, resource_quota, &req,
-      ExecCtx::Get()->Now() + grpc_jwt_verifier_max_delay,
+      grpc_core::ExecCtx::Get()->Now() + grpc_jwt_verifier_max_delay,
       GRPC_CLOSURE_CREATE(on_keys_retrieved, ctx, grpc_schedule_on_exec_ctx),
       &ctx->responses[HTTP_RESPONSE_KEYS]);
   grpc_resource_quota_unref_internal(resource_quota);
@@ -827,9 +827,10 @@ static void retrieve_key_and_verify(verifier_cb_ctx* ctx) {
      channel. This would allow us to cancel an authentication query when under
      extreme memory pressure. */
   resource_quota = grpc_resource_quota_create("jwt_verifier");
-  grpc_httpcli_get(&ctx->verifier->http_ctx, &ctx->pollent, resource_quota,
-                   &req, ExecCtx::Get()->Now() + grpc_jwt_verifier_max_delay,
-                   http_cb, &ctx->responses[rsp_idx]);
+  grpc_httpcli_get(
+      &ctx->verifier->http_ctx, &ctx->pollent, resource_quota, &req,
+      grpc_core::ExecCtx::Get()->Now() + grpc_jwt_verifier_max_delay, http_cb,
+      &ctx->responses[rsp_idx]);
   grpc_resource_quota_unref_internal(resource_quota);
   gpr_free(req.host);
   gpr_free(req.http.path);
diff --git a/src/core/lib/security/credentials/oauth2/oauth2_credentials.cc b/src/core/lib/security/credentials/oauth2/oauth2_credentials.cc
index b653705609..71be15a46e 100644
--- a/src/core/lib/security/credentials/oauth2/oauth2_credentials.cc
+++ b/src/core/lib/security/credentials/oauth2/oauth2_credentials.cc
@@ -217,7 +217,7 @@ static void on_oauth2_token_fetcher_http_response(void* user_data,
   c->token_fetch_pending = false;
   c->access_token_md = GRPC_MDELEM_REF(access_token_md);
   c->token_expiration = status == GRPC_CREDENTIALS_OK
-                            ? ExecCtx::Get()->Now() + token_lifetime
+                            ? grpc_core::ExecCtx::Get()->Now() + token_lifetime
                             : 0;
   grpc_oauth2_pending_get_request_metadata* pending_request =
       c->pending_requests;
@@ -256,7 +256,8 @@ static bool oauth2_token_fetcher_get_request_metadata(
   grpc_mdelem cached_access_token_md = GRPC_MDNULL;
   gpr_mu_lock(&c->mu);
   if (!GRPC_MDISNULL(c->access_token_md) &&
-      (c->token_expiration - ExecCtx::Get()->Now() > refresh_threshold)) {
+      (c->token_expiration - grpc_core::ExecCtx::Get()->Now() >
+       refresh_threshold)) {
     cached_access_token_md = GRPC_MDELEM_REF(c->access_token_md);
   }
   if (!GRPC_MDISNULL(cached_access_token_md)) {
@@ -288,7 +289,7 @@ static bool oauth2_token_fetcher_get_request_metadata(
     c->fetch_func(grpc_credentials_metadata_request_create(creds),
                   &c->httpcli_context, &c->pollent,
                   on_oauth2_token_fetcher_http_response,
-                  ExecCtx::Get()->Now() + refresh_threshold);
+                  grpc_core::ExecCtx::Get()->Now() + refresh_threshold);
   }
   return false;
 }
@@ -514,7 +515,7 @@ grpc_call_credentials* grpc_access_token_credentials_create(
   gpr_ref_init(&c->base.refcount, 1);
   char* token_md_value;
   gpr_asprintf(&token_md_value, "Bearer %s", access_token);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   c->access_token_md = grpc_mdelem_from_slices(
       grpc_slice_from_static_string(GRPC_AUTHORIZATION_METADATA_KEY),
       grpc_slice_from_copied_string(token_md_value));
diff --git a/src/core/lib/security/credentials/plugin/plugin_credentials.cc b/src/core/lib/security/credentials/plugin/plugin_credentials.cc
index 025d024617..7634cadc3a 100644
--- a/src/core/lib/security/credentials/plugin/plugin_credentials.cc
+++ b/src/core/lib/security/credentials/plugin/plugin_credentials.cc
@@ -116,8 +116,8 @@ static void plugin_md_request_metadata_ready(void* request,
                                              grpc_status_code status,
                                              const char* error_details) {
   /* called from application code */
-  ExecCtx _local_exec_ctx(GRPC_EXEC_CTX_FLAG_IS_FINISHED |
-                          GRPC_EXEC_CTX_FLAG_THREAD_RESOURCE_LOOP);
+  grpc_core::ExecCtx _local_exec_ctx(GRPC_EXEC_CTX_FLAG_IS_FINISHED |
+                                     GRPC_EXEC_CTX_FLAG_THREAD_RESOURCE_LOOP);
   grpc_plugin_credentials_pending_request* r =
       (grpc_plugin_credentials_pending_request*)request;
   if (GRPC_TRACER_ON(grpc_plugin_credentials_trace)) {
diff --git a/src/core/lib/security/transport/security_handshaker.cc b/src/core/lib/security/transport/security_handshaker.cc
index 4ed2ec55bd..0df3375d34 100644
--- a/src/core/lib/security/transport/security_handshaker.cc
+++ b/src/core/lib/security/transport/security_handshaker.cc
@@ -255,7 +255,7 @@ static void on_handshake_next_done_grpc_wrapper(
   security_handshaker* h = (security_handshaker*)user_data;
   // This callback will be invoked by TSI in a non-grpc thread, so it's
   // safe to create our own exec_ctx here.
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   gpr_mu_lock(&h->mu);
   grpc_error* error = on_handshake_next_done_locked(
       h, result, bytes_to_send, bytes_to_send_size, handshaker_result);
diff --git a/src/core/lib/security/transport/server_auth_filter.cc b/src/core/lib/security/transport/server_auth_filter.cc
index 86817076f8..5f5ff7c09c 100644
--- a/src/core/lib/security/transport/server_auth_filter.cc
+++ b/src/core/lib/security/transport/server_auth_filter.cc
@@ -118,7 +118,7 @@ static void on_md_processing_done(
     grpc_status_code status, const char* error_details) {
   grpc_call_element* elem = (grpc_call_element*)user_data;
   call_data* calld = (call_data*)elem->call_data;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   // If the call was not cancelled while we were in flight, process the result.
   if (gpr_atm_full_cas(&calld->state, (gpr_atm)STATE_INIT,
                        (gpr_atm)STATE_DONE)) {
diff --git a/src/core/lib/slice/slice.cc b/src/core/lib/slice/slice.cc
index 6e1554d471..3604bb77a8 100644
--- a/src/core/lib/slice/slice.cc
+++ b/src/core/lib/slice/slice.cc
@@ -67,7 +67,7 @@ grpc_slice grpc_slice_ref(grpc_slice slice) {
 
 /* Public API */
 void grpc_slice_unref(grpc_slice slice) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_slice_unref_internal(slice);
 }
 
diff --git a/src/core/lib/slice/slice_buffer.cc b/src/core/lib/slice/slice_buffer.cc
index 4bc54c303f..0a4d48f114 100644
--- a/src/core/lib/slice/slice_buffer.cc
+++ b/src/core/lib/slice/slice_buffer.cc
@@ -73,7 +73,7 @@ void grpc_slice_buffer_destroy_internal(grpc_slice_buffer* sb) {
 }
 
 void grpc_slice_buffer_destroy(grpc_slice_buffer* sb) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_slice_buffer_destroy_internal(sb);
 }
 
@@ -172,7 +172,7 @@ void grpc_slice_buffer_reset_and_unref_internal(grpc_slice_buffer* sb) {
 }
 
 void grpc_slice_buffer_reset_and_unref(grpc_slice_buffer* sb) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_slice_buffer_reset_and_unref_internal(sb);
 }
 
diff --git a/src/core/lib/surface/alarm.cc b/src/core/lib/surface/alarm.cc
index 7aee100f3f..8dcfb1ddb5 100644
--- a/src/core/lib/surface/alarm.cc
+++ b/src/core/lib/surface/alarm.cc
@@ -47,7 +47,7 @@ static void alarm_ref(grpc_alarm* alarm) { gpr_ref(&alarm->refs); }
 
 static void alarm_unref(grpc_alarm* alarm) {
   if (gpr_unref(&alarm->refs)) {
-    ExecCtx _local_exec_ctx;
+    grpc_core::ExecCtx _local_exec_ctx;
     if (alarm->cq != NULL) {
       GRPC_CQ_INTERNAL_UNREF(alarm->cq, "alarm");
     }
@@ -117,7 +117,7 @@ grpc_alarm* grpc_alarm_create(void* reserved) {
 
 void grpc_alarm_set(grpc_alarm* alarm, grpc_completion_queue* cq,
                     gpr_timespec deadline, void* tag, void* reserved) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   GRPC_CQ_INTERNAL_REF(cq, "alarm");
   alarm->cq = cq;
@@ -129,7 +129,7 @@ void grpc_alarm_set(grpc_alarm* alarm, grpc_completion_queue* cq,
 }
 
 void grpc_alarm_cancel(grpc_alarm* alarm, void* reserved) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_timer_cancel(&alarm->alarm);
 }
 
diff --git a/src/core/lib/surface/byte_buffer.cc b/src/core/lib/surface/byte_buffer.cc
index 6a9b13bb41..03097c6896 100644
--- a/src/core/lib/surface/byte_buffer.cc
+++ b/src/core/lib/surface/byte_buffer.cc
@@ -71,7 +71,7 @@ grpc_byte_buffer* grpc_byte_buffer_copy(grpc_byte_buffer* bb) {
 
 void grpc_byte_buffer_destroy(grpc_byte_buffer* bb) {
   if (!bb) return;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   switch (bb->type) {
     case GRPC_BB_RAW:
       grpc_slice_buffer_destroy_internal(&bb->data.raw.slice_buffer);
diff --git a/src/core/lib/surface/byte_buffer_reader.cc b/src/core/lib/surface/byte_buffer_reader.cc
index 9a9e26ecdc..c5f8df3dda 100644
--- a/src/core/lib/surface/byte_buffer_reader.cc
+++ b/src/core/lib/surface/byte_buffer_reader.cc
@@ -42,7 +42,7 @@ static int is_compressed(grpc_byte_buffer* buffer) {
 
 int grpc_byte_buffer_reader_init(grpc_byte_buffer_reader* reader,
                                  grpc_byte_buffer* buffer) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_slice_buffer decompressed_slices_buffer;
   reader->buffer_in = buffer;
   switch (reader->buffer_in->type) {
@@ -110,7 +110,7 @@ grpc_slice grpc_byte_buffer_reader_readall(grpc_byte_buffer_reader* reader) {
   grpc_slice out_slice = GRPC_SLICE_MALLOC(input_size);
   uint8_t* const outbuf = GRPC_SLICE_START_PTR(out_slice); /* just an alias */
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   while (grpc_byte_buffer_reader_next(reader, &in_slice) != 0) {
     const size_t slice_length = GRPC_SLICE_LENGTH(in_slice);
     memcpy(&(outbuf[bytes_read]), GRPC_SLICE_START_PTR(in_slice), slice_length);
diff --git a/src/core/lib/surface/call.cc b/src/core/lib/surface/call.cc
index bbb7a39e29..cb858785f2 100644
--- a/src/core/lib/surface/call.cc
+++ b/src/core/lib/surface/call.cc
@@ -561,7 +561,7 @@ void grpc_call_unref(grpc_call* c) {
   if (!gpr_unref(&c->ext_ref)) return;
 
   child_call* cc = c->child;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   GPR_TIMER_BEGIN("grpc_call_unref", 0);
   GRPC_API_TRACE("grpc_call_unref(c=%p)", 1, (c));
@@ -602,7 +602,7 @@ void grpc_call_unref(grpc_call* c) {
 grpc_call_error grpc_call_cancel(grpc_call* call, void* reserved) {
   GRPC_API_TRACE("grpc_call_cancel(call=%p, reserved=%p)", 2, (call, reserved));
   GPR_ASSERT(!reserved);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   cancel_with_error(call, STATUS_FROM_API_OVERRIDE, GRPC_ERROR_CANCELLED);
 
   return GRPC_CALL_OK;
@@ -652,7 +652,7 @@ grpc_call_error grpc_call_cancel_with_status(grpc_call* c,
                                              grpc_status_code status,
                                              const char* description,
                                              void* reserved) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_API_TRACE(
       "grpc_call_cancel_with_status("
       "c=%p, status=%d, description=%s, reserved=%p)",
@@ -2034,7 +2034,7 @@ done_with_error:
 
 grpc_call_error grpc_call_start_batch(grpc_call* call, const grpc_op* ops,
                                       size_t nops, void* tag, void* reserved) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_call_error err;
 
   GRPC_API_TRACE(
diff --git a/src/core/lib/surface/call_details.cc b/src/core/lib/surface/call_details.cc
index 03ce7f88fb..7d81ba9e22 100644
--- a/src/core/lib/surface/call_details.cc
+++ b/src/core/lib/surface/call_details.cc
@@ -34,7 +34,7 @@ void grpc_call_details_init(grpc_call_details* cd) {
 
 void grpc_call_details_destroy(grpc_call_details* cd) {
   GRPC_API_TRACE("grpc_call_details_destroy(cd=%p)", 1, (cd));
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_slice_unref_internal(cd->method);
   grpc_slice_unref_internal(cd->host);
 }
diff --git a/src/core/lib/surface/channel.cc b/src/core/lib/surface/channel.cc
index 7725351f74..80ba47676e 100644
--- a/src/core/lib/surface/channel.cc
+++ b/src/core/lib/surface/channel.cc
@@ -248,7 +248,7 @@ char* grpc_channel_get_target(grpc_channel* channel) {
 
 void grpc_channel_get_info(grpc_channel* channel,
                            const grpc_channel_info* channel_info) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_channel_element* elem =
       grpc_channel_stack_element(CHANNEL_STACK_FROM_CHANNEL(channel), 0);
   elem->filter->get_channel_info(elem, channel_info);
@@ -296,7 +296,7 @@ grpc_call* grpc_channel_create_call(grpc_channel* channel,
                                     grpc_slice method, const grpc_slice* host,
                                     gpr_timespec deadline, void* reserved) {
   GPR_ASSERT(!reserved);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_call* call = grpc_channel_create_call_internal(
       channel, parent_call, propagation_mask, cq, NULL,
       grpc_mdelem_from_slices(GRPC_MDSTR_PATH, grpc_slice_ref_internal(method)),
@@ -329,7 +329,7 @@ void* grpc_channel_register_call(grpc_channel* channel, const char* method,
       "grpc_channel_register_call(channel=%p, method=%s, host=%s, reserved=%p)",
       4, (channel, method, host, reserved));
   GPR_ASSERT(!reserved);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   rc->path = grpc_mdelem_from_slices(
       GRPC_MDSTR_PATH,
@@ -364,7 +364,7 @@ grpc_call* grpc_channel_create_registered_call(
        registered_call_handle, deadline.tv_sec, deadline.tv_nsec,
        (int)deadline.clock_type, reserved));
   GPR_ASSERT(!reserved);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_call* call = grpc_channel_create_call_internal(
       channel, parent_call, propagation_mask, completion_queue, NULL,
       GRPC_MDELEM_REF(rc->path), GRPC_MDELEM_REF(rc->authority),
@@ -407,7 +407,7 @@ static void destroy_channel(void* arg, grpc_error* error) {
 void grpc_channel_destroy(grpc_channel* channel) {
   grpc_transport_op* op = grpc_make_transport_op(NULL);
   grpc_channel_element* elem;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_API_TRACE("grpc_channel_destroy(channel=%p)", 1, (channel));
   op->disconnect_with_error =
       GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel Destroyed");
diff --git a/src/core/lib/surface/channel_ping.cc b/src/core/lib/surface/channel_ping.cc
index 06cdbf6c73..545b8fe6ee 100644
--- a/src/core/lib/surface/channel_ping.cc
+++ b/src/core/lib/surface/channel_ping.cc
@@ -51,7 +51,7 @@ void grpc_channel_ping(grpc_channel* channel, grpc_completion_queue* cq,
   ping_result* pr = (ping_result*)gpr_malloc(sizeof(*pr));
   grpc_channel_element* top_elem =
       grpc_channel_stack_element(grpc_channel_get_channel_stack(channel), 0);
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GPR_ASSERT(reserved == NULL);
   pr->tag = tag;
   pr->cq = cq;
diff --git a/src/core/lib/surface/completion_queue.cc b/src/core/lib/surface/completion_queue.cc
index 0b0a8d070d..24c502881a 100644
--- a/src/core/lib/surface/completion_queue.cc
+++ b/src/core/lib/surface/completion_queue.cc
@@ -124,7 +124,7 @@ static grpc_error* non_polling_poller_work(grpc_pollset* pollset,
   while (!npp->shutdown && !w.kicked &&
          !gpr_cv_wait(&w.cv, &npp->mu, deadline_ts))
     ;
-  ExecCtx::Get()->InvalidateNow();
+  grpc_core::ExecCtx::Get()->InvalidateNow();
   if (&w == npp->root) {
     npp->root = w.next;
     if (&w == npp->root) {
@@ -359,7 +359,7 @@ int grpc_completion_queue_thread_local_cache_flush(grpc_completion_queue* cq,
   if (storage != NULL &&
       (grpc_completion_queue*)gpr_tls_get(&g_cached_cq) == cq) {
     *tag = storage->tag;
-    ExecCtx _local_exec_ctx;
+    grpc_core::ExecCtx _local_exec_ctx;
     *ok = (storage->next & (uintptr_t)(1)) == 1;
     storage->done(storage->done_arg, storage);
     ret = 1;
@@ -395,7 +395,7 @@ static bool cq_event_queue_push(grpc_cq_event_queue* q, grpc_cq_completion* c) {
 
 static grpc_cq_completion* cq_event_queue_pop(grpc_cq_event_queue* q) {
   grpc_cq_completion* c = NULL;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   if (gpr_spinlock_trylock(&q->queue_lock)) {
     GRPC_STATS_INC_CQ_EV_QUEUE_TRYLOCK_SUCCESSES();
@@ -440,7 +440,7 @@ grpc_completion_queue* grpc_completion_queue_create_internal(
   const cq_poller_vtable* poller_vtable =
       &g_poller_vtable_by_poller_type[polling_type];
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_STATS_INC_CQS_CREATED();
 
   cq = (grpc_completion_queue*)gpr_zalloc(sizeof(grpc_completion_queue) +
@@ -790,7 +790,7 @@ typedef struct {
   bool first_loop;
 } cq_is_finished_arg;
 
-class ExecCtxNext : public ExecCtx {
+class ExecCtxNext : public grpc_core::ExecCtx {
  public:
   ExecCtxNext(void* arg) : ExecCtx(0), check_ready_to_finish_arg_(arg) {}
 
@@ -818,7 +818,7 @@ class ExecCtxNext : public ExecCtx {
         return true;
       }
     }
-    return !a->first_loop && a->deadline < ExecCtx::Get()->Now();
+    return !a->first_loop && a->deadline < grpc_core::ExecCtx::Get()->Now();
   }
 
  private:
@@ -929,7 +929,7 @@ static grpc_event cq_next(grpc_completion_queue* cq, gpr_timespec deadline,
     }
 
     if (!is_finished_arg.first_loop &&
-        ExecCtx::Get()->Now() >= deadline_millis) {
+        grpc_core::ExecCtx::Get()->Now() >= deadline_millis) {
       memset(&ret, 0, sizeof(ret));
       ret.type = GRPC_QUEUE_TIMEOUT;
       dump_pending_tags(cq);
@@ -1045,7 +1045,7 @@ static void del_plucker(grpc_completion_queue* cq, void* tag,
   GPR_UNREACHABLE_CODE(return );
 }
 
-class ExecCtxPluck : public ExecCtx {
+class ExecCtxPluck : public grpc_core::ExecCtx {
  public:
   ExecCtxPluck(void* arg) : ExecCtx(0), check_ready_to_finish_arg_(arg) {}
 
@@ -1079,7 +1079,7 @@ class ExecCtxPluck : public ExecCtx {
       }
       gpr_mu_unlock(cq->mu);
     }
-    return !a->first_loop && a->deadline < ExecCtx::Get()->Now();
+    return !a->first_loop && a->deadline < grpc_core::ExecCtx::Get()->Now();
   }
 
  private:
@@ -1169,7 +1169,7 @@ static grpc_event cq_pluck(grpc_completion_queue* cq, void* tag,
       break;
     }
     if (!is_finished_arg.first_loop &&
-        ExecCtx::Get()->Now() >= deadline_millis) {
+        grpc_core::ExecCtx::Get()->Now() >= deadline_millis) {
       del_plucker(cq, tag, &worker);
       gpr_mu_unlock(cq->mu);
       memset(&ret, 0, sizeof(ret));
@@ -1250,7 +1250,7 @@ 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) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_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);
@@ -1263,7 +1263,7 @@ void grpc_completion_queue_destroy(grpc_completion_queue* cq) {
   GPR_TIMER_BEGIN("grpc_completion_queue_destroy", 0);
   grpc_completion_queue_shutdown(cq);
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   GRPC_CQ_INTERNAL_UNREF(cq, "destroy");
 
   GPR_TIMER_END("grpc_completion_queue_destroy", 0);
diff --git a/src/core/lib/surface/init.cc b/src/core/lib/surface/init.cc
index 20e17a7f60..fdbf926f77 100644
--- a/src/core/lib/surface/init.cc
+++ b/src/core/lib/surface/init.cc
@@ -116,7 +116,7 @@ void grpc_init(void) {
   int i;
   gpr_once_init(&g_basic_init, do_basic_init);
 
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   gpr_mu_lock(&g_init_mu);
   if (++g_initializations == 1) {
     gpr_time_init();
@@ -175,7 +175,7 @@ void grpc_init(void) {
 void grpc_shutdown(void) {
   int i;
   GRPC_API_TRACE("grpc_shutdown(void)", 0, ());
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   gpr_mu_lock(&g_init_mu);
   if (--g_initializations == 0) {
     grpc_executor_shutdown();
diff --git a/src/core/lib/surface/lame_client.cc b/src/core/lib/surface/lame_client.cc
index da081e68cb..3bbdd21285 100644
--- a/src/core/lib/surface/lame_client.cc
+++ b/src/core/lib/surface/lame_client.cc
@@ -156,7 +156,7 @@ extern "C" const grpc_channel_filter grpc_lame_filter = {
 grpc_channel* grpc_lame_client_channel_create(const char* target,
                                               grpc_status_code error_code,
                                               const char* error_message) {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   grpc_channel_element* elem;
   grpc_channel* channel =
       grpc_channel_create(target, NULL, GRPC_CLIENT_LAME_CHANNEL, NULL);
diff --git a/src/core/lib/surface/server.cc b/src/core/lib/surface/server.cc
index 0d4435d556..835e495495 100644
--- a/src/core/lib/surface/server.cc
+++ b/src/core/lib/surface/server.cc
@@ -1022,7 +1022,7 @@ static void start_listeners(void* s, grpc_error* error) {
 
 void grpc_server_start(grpc_server* server) {
   size_t i;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   GRPC_API_TRACE("grpc_server_start(server=%p)", 1, (server));
 
@@ -1168,7 +1168,7 @@ void grpc_server_shutdown_and_notify(grpc_server* server,
   listener* l;
   shutdown_tag* sdt;
   channel_broadcaster broadcaster;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   GRPC_API_TRACE("grpc_server_shutdown_and_notify(server=%p, cq=%p, tag=%p)", 3,
                  (server, cq, tag));
@@ -1227,7 +1227,7 @@ void grpc_server_shutdown_and_notify(grpc_server* server,
 
 void grpc_server_cancel_all_calls(grpc_server* server) {
   channel_broadcaster broadcaster;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   GRPC_API_TRACE("grpc_server_cancel_all_calls(server=%p)", 1, (server));
 
@@ -1242,7 +1242,7 @@ void grpc_server_cancel_all_calls(grpc_server* server) {
 
 void grpc_server_destroy(grpc_server* server) {
   listener* l;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
 
   GRPC_API_TRACE("grpc_server_destroy(server=%p)", 1, (server));
 
@@ -1324,7 +1324,7 @@ grpc_call_error grpc_server_request_call(
     grpc_completion_queue* cq_bound_to_call,
     grpc_completion_queue* cq_for_notification, void* tag) {
   grpc_call_error error;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   requested_call* rc = (requested_call*)gpr_malloc(sizeof(*rc));
   GRPC_STATS_INC_SERVER_REQUESTED_CALLS();
   GRPC_API_TRACE(
@@ -1371,7 +1371,7 @@ grpc_call_error grpc_server_request_registered_call(
     grpc_completion_queue* cq_bound_to_call,
     grpc_completion_queue* cq_for_notification, void* tag) {
   grpc_call_error error;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   requested_call* rc = (requested_call*)gpr_malloc(sizeof(*rc));
   registered_method* rm = (registered_method*)rmp;
   GRPC_STATS_INC_SERVER_REQUESTED_CALLS();
diff --git a/src/core/lib/transport/bdp_estimator.cc b/src/core/lib/transport/bdp_estimator.cc
index 4e279b4d94..d2b6e5db25 100644
--- a/src/core/lib/transport/bdp_estimator.cc
+++ b/src/core/lib/transport/bdp_estimator.cc
@@ -79,7 +79,7 @@ grpc_millis BdpEstimator::CompletePing() {
   }
   ping_state_ = PingState::UNSCHEDULED;
   accumulator_ = 0;
-  return ExecCtx::Get()->Now() + inter_ping_delay_;
+  return grpc_core::ExecCtx::Get()->Now() + inter_ping_delay_;
 }
 
 }  // namespace grpc_core
diff --git a/src/core/lib/transport/status_conversion.cc b/src/core/lib/transport/status_conversion.cc
index 61470b8c78..46cba4292b 100644
--- a/src/core/lib/transport/status_conversion.cc
+++ b/src/core/lib/transport/status_conversion.cc
@@ -46,8 +46,9 @@ grpc_status_code grpc_http2_error_to_grpc_status(grpc_http2_error_code error,
     case GRPC_HTTP2_CANCEL:
       /* http2 cancel translates to STATUS_CANCELLED iff deadline hasn't been
        * exceeded */
-      return ExecCtx::Get()->Now() > deadline ? GRPC_STATUS_DEADLINE_EXCEEDED
-                                              : GRPC_STATUS_CANCELLED;
+      return grpc_core::ExecCtx::Get()->Now() > deadline
+                 ? GRPC_STATUS_DEADLINE_EXCEEDED
+                 : GRPC_STATUS_CANCELLED;
     case GRPC_HTTP2_ENHANCE_YOUR_CALM:
       return GRPC_STATUS_RESOURCE_EXHAUSTED;
     case GRPC_HTTP2_INADEQUATE_SECURITY:
diff --git a/src/core/lib/transport/transport.cc b/src/core/lib/transport/transport.cc
index ca80a7404d..ed2f02de55 100644
--- a/src/core/lib/transport/transport.cc
+++ b/src/core/lib/transport/transport.cc
@@ -62,7 +62,8 @@ void grpc_stream_unref(grpc_stream_refcount* refcount, const char* reason) {
 void grpc_stream_unref(grpc_stream_refcount* refcount) {
 #endif
   if (gpr_unref(&refcount->refs)) {
-    if (ExecCtx::Get()->flags() & GRPC_EXEC_CTX_FLAG_THREAD_RESOURCE_LOOP) {
+    if (grpc_core::ExecCtx::Get()->flags() &
+        GRPC_EXEC_CTX_FLAG_THREAD_RESOURCE_LOOP) {
       /* Ick.
          The thread we're running on MAY be owned (indirectly) by a call-stack.
          If that's the case, destroying the call-stack MAY try to destroy the
diff --git a/src/cpp/common/channel_arguments.cc b/src/cpp/common/channel_arguments.cc
index 0bcfac2845..82d687c530 100644
--- a/src/cpp/common/channel_arguments.cc
+++ b/src/cpp/common/channel_arguments.cc
@@ -67,7 +67,7 @@ ChannelArguments::ChannelArguments(const ChannelArguments& other)
 }
 
 ChannelArguments::~ChannelArguments() {
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   for (auto it = args_.begin(); it != args_.end(); ++it) {
     if (it->type == GRPC_ARG_POINTER) {
       it->value.pointer.vtable->destroy(it->value.pointer.p);
@@ -95,7 +95,7 @@ void ChannelArguments::SetSocketMutator(grpc_socket_mutator* mutator) {
   }
   grpc_arg mutator_arg = grpc_socket_mutator_to_arg(mutator);
   bool replaced = false;
-  ExecCtx _local_exec_ctx;
+  grpc_core::ExecCtx _local_exec_ctx;
   for (auto it = args_.begin(); it != args_.end(); ++it) {
     if (it->type == mutator_arg.type &&
         grpc::string(it->key) == grpc::string(mutator_arg.key)) {