Merge github.com:grpc/grpc into vector

25 files changed, 129 insertions, 180 deletions

diff --git a/src/core/ext/filters/client_channel/channel_connectivity.cc b/src/core/ext/filters/client_channel/channel_connectivity.cc
index a05a11dad1..31a8fc39ce 100644
--- a/src/core/ext/filters/client_channel/channel_connectivity.cc
+++ b/src/core/ext/filters/client_channel/channel_connectivity.cc
@@ -188,8 +188,8 @@ static void watcher_timer_init(grpc_exec_ctx *exec_ctx, void *arg,
   watcher_timer_init_arg *wa = (watcher_timer_init_arg *)arg;
 
   grpc_timer_init(exec_ctx, &wa->w->alarm,
-                  gpr_convert_clock_type(wa->deadline, GPR_CLOCK_MONOTONIC),
-                  &wa->w->on_timeout, gpr_now(GPR_CLOCK_MONOTONIC));
+                  grpc_timespec_to_millis_round_up(wa->deadline),
+                  &wa->w->on_timeout);
   gpr_free(wa);
 }
 
diff --git a/src/core/ext/filters/client_channel/client_channel.cc b/src/core/ext/filters/client_channel/client_channel.cc
index 8bff7548ac..22c2bc8880 100644
--- a/src/core/ext/filters/client_channel/client_channel.cc
+++ b/src/core/ext/filters/client_channel/client_channel.cc
@@ -71,7 +71,7 @@ typedef enum {
 
 typedef struct {
   gpr_refcount refs;
-  gpr_timespec timeout;
+  grpc_millis timeout;
   wait_for_ready_value wait_for_ready;
 } method_parameters;
 
@@ -101,17 +101,18 @@ static bool parse_wait_for_ready(grpc_json *field,
   return true;
 }
 
-static bool parse_timeout(grpc_json *field, gpr_timespec *timeout) {
+static bool parse_timeout(grpc_json *field, grpc_millis *timeout) {
   if (field->type != GRPC_JSON_STRING) return false;
   size_t len = strlen(field->value);
   if (field->value[len - 1] != 's') return false;
   char *buf = gpr_strdup(field->value);
   buf[len - 1] = '\0';  // Remove trailing 's'.
   char *decimal_point = strchr(buf, '.');
+  int nanos = 0;
   if (decimal_point != NULL) {
     *decimal_point = '\0';
-    timeout->tv_nsec = gpr_parse_nonnegative_int(decimal_point + 1);
-    if (timeout->tv_nsec == -1) {
+    nanos = gpr_parse_nonnegative_int(decimal_point + 1);
+    if (nanos == -1) {
       gpr_free(buf);
       return false;
     }
@@ -130,24 +131,25 @@ static bool parse_timeout(grpc_json *field, gpr_timespec *timeout) {
         gpr_free(buf);
         return false;
     }
-    timeout->tv_nsec *= multiplier;
+    nanos *= multiplier;
   }
-  timeout->tv_sec = gpr_parse_nonnegative_int(buf);
+  int seconds = gpr_parse_nonnegative_int(buf);
   gpr_free(buf);
-  if (timeout->tv_sec == -1) return false;
+  if (seconds == -1) return false;
+  *timeout = seconds * GPR_MS_PER_SEC + nanos / GPR_NS_PER_MS;
   return true;
 }
 
 static void *method_parameters_create_from_json(const grpc_json *json) {
   wait_for_ready_value wait_for_ready = WAIT_FOR_READY_UNSET;
-  gpr_timespec timeout = {0, 0, GPR_TIMESPAN};
+  grpc_millis timeout = 0;
   for (grpc_json *field = json->child; field != NULL; field = field->next) {
     if (field->key == NULL) continue;
     if (strcmp(field->key, "waitForReady") == 0) {
       if (wait_for_ready != WAIT_FOR_READY_UNSET) return NULL;  // Duplicate.
       if (!parse_wait_for_ready(field, &wait_for_ready)) return NULL;
     } else if (strcmp(field->key, "timeout") == 0) {
-      if (timeout.tv_sec > 0 || timeout.tv_nsec > 0) return NULL;  // Duplicate.
+      if (timeout > 0) return NULL;  // Duplicate.
       if (!parse_timeout(field, &timeout)) return NULL;
     }
   }
@@ -826,7 +828,7 @@ typedef struct client_channel_call_data {
 
   grpc_slice path;  // Request path.
   gpr_timespec call_start_time;
-  gpr_timespec deadline;
+  grpc_millis deadline;
   gpr_arena *arena;
   grpc_call_stack *owning_call;
   grpc_call_combiner *call_combiner;
@@ -979,11 +981,11 @@ static void apply_service_config_to_call_locked(grpc_exec_ctx *exec_ctx,
       // If the deadline from the service config is shorter than the one
       // from the client API, reset the deadline timer.
       if (chand->deadline_checking_enabled &&
-          gpr_time_cmp(calld->method_params->timeout,
-                       gpr_time_0(GPR_TIMESPAN)) != 0) {
-        const gpr_timespec per_method_deadline =
-            gpr_time_add(calld->call_start_time, calld->method_params->timeout);
-        if (gpr_time_cmp(per_method_deadline, calld->deadline) < 0) {
+          calld->method_params->timeout != 0) {
+        const grpc_millis per_method_deadline =
+            grpc_timespec_to_millis_round_up(calld->call_start_time) +
+            calld->method_params->timeout;
+        if (per_method_deadline < calld->deadline) {
           calld->deadline = per_method_deadline;
           grpc_deadline_state_reset(exec_ctx, elem, calld->deadline);
         }
@@ -1422,7 +1424,7 @@ static grpc_error *cc_init_call_elem(grpc_exec_ctx *exec_ctx,
   // Initialize data members.
   calld->path = grpc_slice_ref_internal(args->path);
   calld->call_start_time = args->start_time;
-  calld->deadline = gpr_convert_clock_type(args->deadline, GPR_CLOCK_MONOTONIC);
+  calld->deadline = args->deadline;
   calld->arena = args->arena;
   calld->owning_call = args->call_stack;
   calld->call_combiner = args->call_combiner;
diff --git a/src/core/ext/filters/client_channel/client_channel.h b/src/core/ext/filters/client_channel/client_channel.h
index b32f378c6c..152fe2365a 100644
--- a/src/core/ext/filters/client_channel/client_channel.h
+++ b/src/core/ext/filters/client_channel/client_channel.h
@@ -60,4 +60,4 @@ grpc_subchannel_call *grpc_client_channel_get_subchannel_call(
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_H */
diff --git a/src/core/ext/filters/client_channel/client_channel_factory.h b/src/core/ext/filters/client_channel/client_channel_factory.h
index bad8b97042..4273c90058 100644
--- a/src/core/ext/filters/client_channel/client_channel_factory.h
+++ b/src/core/ext/filters/client_channel/client_channel_factory.h
@@ -82,4 +82,4 @@ grpc_arg grpc_client_channel_factory_create_channel_arg(
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_FACTORY_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CLIENT_CHANNEL_FACTORY_H */
diff --git a/src/core/ext/filters/client_channel/connector.h b/src/core/ext/filters/client_channel/connector.h
index 79ccb0d9bf..b71e0aab00 100644
--- a/src/core/ext/filters/client_channel/connector.h
+++ b/src/core/ext/filters/client_channel/connector.h
@@ -38,7 +38,7 @@ typedef struct {
   /** set of pollsets interested in this connection */
   grpc_pollset_set *interested_parties;
   /** deadline for connection */
-  gpr_timespec deadline;
+  grpc_millis deadline;
   /** channel arguments (to be passed to transport) */
   const grpc_channel_args *channel_args;
 } grpc_connect_in_args;
@@ -78,4 +78,4 @@ void grpc_connector_shutdown(grpc_exec_ctx *exec_ctx, grpc_connector *connector,
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CONNECTOR_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_CONNECTOR_H */
diff --git a/src/core/ext/filters/client_channel/http_connect_handshaker.h b/src/core/ext/filters/client_channel/http_connect_handshaker.h
index 5042c61bec..05a23cdba3 100644
--- a/src/core/ext/filters/client_channel/http_connect_handshaker.h
+++ b/src/core/ext/filters/client_channel/http_connect_handshaker.h
@@ -39,4 +39,4 @@ void grpc_http_connect_register_handshaker_factory();
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_CONNECT_HANDSHAKER_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_CONNECT_HANDSHAKER_H */
diff --git a/src/core/ext/filters/client_channel/http_proxy.h b/src/core/ext/filters/client_channel/http_proxy.h
index 65d52334af..bdad03def3 100644
--- a/src/core/ext/filters/client_channel/http_proxy.h
+++ b/src/core/ext/filters/client_channel/http_proxy.h
@@ -29,4 +29,4 @@ void grpc_register_http_proxy_mapper();
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_PROXY_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_HTTP_PROXY_H */
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
index d8e314d1f9..ffd58129c6 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
@@ -103,6 +103,7 @@
 #include "src/core/ext/filters/client_channel/parse_address.h"
 #include "src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h"
 #include "src/core/ext/filters/client_channel/subchannel_index.h"
+#include "src/core/lib/backoff/backoff.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/channel_stack.h"
 #include "src/core/lib/iomgr/combiner.h"
@@ -112,7 +113,6 @@
 #include "src/core/lib/slice/slice_hash_table.h"
 #include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
-#include "src/core/lib/support/backoff.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/surface/call.h"
 #include "src/core/lib/surface/channel.h"
@@ -345,9 +345,6 @@ typedef struct glb_lb_policy {
   /** are we currently updating lb_call? */
   bool updating_lb_call;
 
-  /** are we currently updating lb_channel? */
-  bool updating_lb_channel;
-
   /** are we already watching the LB channel's connectivity? */
   bool watching_lb_channel;
 
@@ -360,9 +357,6 @@ typedef struct glb_lb_policy {
   /** called upon changes to the LB channel's connectivity. */
   grpc_closure lb_channel_on_connectivity_changed;
 
-  /** args from the latest update received while already updating, or NULL */
-  grpc_lb_policy_args *pending_update_args;
-
   /************************************************************/
   /*  client data associated with the LB server communication */
   /************************************************************/
@@ -397,7 +391,7 @@ typedef struct glb_lb_policy {
   grpc_slice lb_call_status_details;
 
   /** LB call retry backoff state */
-  gpr_backoff lb_call_backoff_state;
+  grpc_backoff lb_call_backoff_state;
 
   /** LB call retry timer */
   grpc_timer lb_call_retry_timer;
@@ -411,7 +405,7 @@ typedef struct glb_lb_policy {
    * recreated whenever lb_call is replaced. */
   grpc_grpclb_client_stats *client_stats;
   /* Interval and timer for next client load report. */
-  gpr_timespec client_stats_report_interval;
+  grpc_millis client_stats_report_interval;
   grpc_timer client_load_report_timer;
   bool client_load_report_timer_pending;
   bool last_client_load_report_counters_were_zero;
@@ -982,10 +976,6 @@ static void glb_destroy(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   }
   grpc_fake_resolver_response_generator_unref(glb_policy->response_generator);
   grpc_subchannel_index_unref();
-  if (glb_policy->pending_update_args != NULL) {
-    grpc_channel_args_destroy(exec_ctx, glb_policy->pending_update_args->args);
-    gpr_free(glb_policy->pending_update_args);
-  }
   gpr_free(glb_policy);
 }
 
@@ -1010,6 +1000,10 @@ static void glb_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
     grpc_timer_cancel(exec_ctx, &glb_policy->lb_call_retry_timer);
     glb_policy->retry_timer_active = false;
   }
+  if (glb_policy->fallback_timer_active) {
+    grpc_timer_cancel(exec_ctx, &glb_policy->lb_fallback_timer);
+    glb_policy->fallback_timer_active = false;
+  }
 
   pending_pick *pp = glb_policy->pending_picks;
   glb_policy->pending_picks = NULL;
@@ -1130,21 +1124,19 @@ static void start_picking_locked(grpc_exec_ctx *exec_ctx,
   /* start a timer to fall back */
   if (glb_policy->lb_fallback_timeout_ms > 0 &&
       glb_policy->serverlist == NULL && !glb_policy->fallback_timer_active) {
-    gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
-    gpr_timespec deadline = gpr_time_add(
-        now,
-        gpr_time_from_millis(glb_policy->lb_fallback_timeout_ms, GPR_TIMESPAN));
+    grpc_millis deadline =
+        grpc_exec_ctx_now(exec_ctx) + 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,
                       grpc_combiner_scheduler(glb_policy->base.combiner));
     glb_policy->fallback_timer_active = true;
     grpc_timer_init(exec_ctx, &glb_policy->lb_fallback_timer, deadline,
-                    &glb_policy->lb_on_fallback, now);
+                    &glb_policy->lb_on_fallback);
   }
 
   glb_policy->started_picking = true;
-  gpr_backoff_reset(&glb_policy->lb_call_backoff_state);
+  grpc_backoff_reset(&glb_policy->lb_call_backoff_state);
   query_for_backends_locked(exec_ctx, glb_policy);
 }
 
@@ -1270,17 +1262,15 @@ static void maybe_restart_lb_call(grpc_exec_ctx *exec_ctx,
     glb_policy->updating_lb_call = false;
   } else if (!glb_policy->shutting_down) {
     /* if we aren't shutting down, restart the LB client call after some time */
-    gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
-    gpr_timespec next_try =
-        gpr_backoff_step(&glb_policy->lb_call_backoff_state, now);
+    grpc_millis next_try =
+        grpc_backoff_step(exec_ctx, &glb_policy->lb_call_backoff_state);
     if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
       gpr_log(GPR_DEBUG, "Connection to LB server lost (grpclb: %p)...",
               (void *)glb_policy);
-      gpr_timespec timeout = gpr_time_sub(next_try, now);
-      if (gpr_time_cmp(timeout, gpr_time_0(timeout.clock_type)) > 0) {
-        gpr_log(GPR_DEBUG,
-                "... retry_timer_active in %" PRId64 ".%09d seconds.",
-                timeout.tv_sec, timeout.tv_nsec);
+      grpc_millis timeout = next_try - grpc_exec_ctx_now(exec_ctx);
+      if (timeout > 0) {
+        gpr_log(GPR_DEBUG, "... retry_timer_active in %" PRIdPTR "ms.",
+                timeout);
       } else {
         gpr_log(GPR_DEBUG, "... retry_timer_active immediately.");
       }
@@ -1291,7 +1281,7 @@ static void maybe_restart_lb_call(grpc_exec_ctx *exec_ctx,
                       grpc_combiner_scheduler(glb_policy->base.combiner));
     glb_policy->retry_timer_active = true;
     grpc_timer_init(exec_ctx, &glb_policy->lb_call_retry_timer, next_try,
-                    &glb_policy->lb_on_call_retry, now);
+                    &glb_policy->lb_on_call_retry);
   }
   GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &glb_policy->base,
                             "lb_on_server_status_received_locked");
@@ -1302,15 +1292,14 @@ static void send_client_load_report_locked(grpc_exec_ctx *exec_ctx, void *arg,
 
 static void schedule_next_client_load_report(grpc_exec_ctx *exec_ctx,
                                              glb_lb_policy *glb_policy) {
-  const gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
-  const gpr_timespec next_client_load_report_time =
-      gpr_time_add(now, glb_policy->client_stats_report_interval);
+  const grpc_millis next_client_load_report_time =
+      grpc_exec_ctx_now(exec_ctx) + 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));
   grpc_timer_init(exec_ctx, &glb_policy->client_load_report_timer,
                   next_client_load_report_time,
-                  &glb_policy->client_load_report_closure, now);
+                  &glb_policy->client_load_report_closure);
 }
 
 static void client_load_report_done_locked(grpc_exec_ctx *exec_ctx, void *arg,
@@ -1404,12 +1393,10 @@ static void lb_call_init_locked(grpc_exec_ctx *exec_ctx,
    * glb_policy->base.interested_parties, which is comprised of the polling
    * entities from \a client_channel. */
   grpc_slice host = grpc_slice_from_copied_string(glb_policy->server_name);
-  gpr_timespec deadline =
+  grpc_millis deadline =
       glb_policy->lb_call_timeout_ms == 0
-          ? gpr_inf_future(GPR_CLOCK_MONOTONIC)
-          : gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC),
-                         gpr_time_from_millis(glb_policy->lb_call_timeout_ms,
-                                              GPR_TIMESPAN));
+          ? GRPC_MILLIS_INF_FUTURE
+          : grpc_exec_ctx_now(exec_ctx) + glb_policy->lb_call_timeout_ms;
   glb_policy->lb_call = grpc_channel_create_pollset_set_call(
       exec_ctx, glb_policy->lb_channel, NULL, GRPC_PROPAGATE_DEFAULTS,
       glb_policy->base.interested_parties,
@@ -1440,12 +1427,12 @@ static void lb_call_init_locked(grpc_exec_ctx *exec_ctx,
                     lb_on_response_received_locked, glb_policy,
                     grpc_combiner_scheduler(glb_policy->base.combiner));
 
-  gpr_backoff_init(&glb_policy->lb_call_backoff_state,
-                   GRPC_GRPCLB_INITIAL_CONNECT_BACKOFF_SECONDS,
-                   GRPC_GRPCLB_RECONNECT_BACKOFF_MULTIPLIER,
-                   GRPC_GRPCLB_RECONNECT_JITTER,
-                   GRPC_GRPCLB_MIN_CONNECT_TIMEOUT_SECONDS * 1000,
-                   GRPC_GRPCLB_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
+  grpc_backoff_init(&glb_policy->lb_call_backoff_state,
+                    GRPC_GRPCLB_INITIAL_CONNECT_BACKOFF_SECONDS,
+                    GRPC_GRPCLB_RECONNECT_BACKOFF_MULTIPLIER,
+                    GRPC_GRPCLB_RECONNECT_JITTER,
+                    GRPC_GRPCLB_MIN_CONNECT_TIMEOUT_SECONDS * 1000,
+                    GRPC_GRPCLB_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
 
   glb_policy->seen_initial_response = false;
   glb_policy->last_client_load_report_counters_were_zero = false;
@@ -1553,7 +1540,7 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
   memset(ops, 0, sizeof(ops));
   grpc_op *op = ops;
   if (glb_policy->lb_response_payload != NULL) {
-    gpr_backoff_reset(&glb_policy->lb_call_backoff_state);
+    grpc_backoff_reset(&glb_policy->lb_call_backoff_state);
     /* Received data from the LB server. Look inside
      * glb_policy->lb_response_payload, for a serverlist. */
     grpc_byte_buffer_reader bbr;
@@ -1567,16 +1554,14 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
         (response = grpc_grpclb_initial_response_parse(response_slice)) !=
             NULL) {
       if (response->has_client_stats_report_interval) {
-        glb_policy->client_stats_report_interval =
-            gpr_time_max(gpr_time_from_seconds(1, GPR_TIMESPAN),
-                         grpc_grpclb_duration_to_timespec(
-                             &response->client_stats_report_interval));
+        glb_policy->client_stats_report_interval = GPR_MAX(
+            GPR_MS_PER_SEC, grpc_grpclb_duration_to_millis(
+                                &response->client_stats_report_interval));
         if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
           gpr_log(GPR_INFO,
                   "received initial LB response message; "
-                  "client load reporting interval = %" PRId64 ".%09d sec",
-                  glb_policy->client_stats_report_interval.tv_sec,
-                  glb_policy->client_stats_report_interval.tv_nsec);
+                  "client load reporting interval = %" PRIdPTR " milliseconds",
+                  glb_policy->client_stats_report_interval);
         }
         /* take a weak ref (won't prevent calling of \a glb_shutdown() if the
          * strong ref count goes to zero) to be unref'd in
@@ -1757,45 +1742,22 @@ static void glb_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
   }
   const grpc_lb_addresses *addresses =
       (const grpc_lb_addresses *)arg->value.pointer.p;
-
+  // If a non-empty serverlist hasn't been received from the balancer,
+  // propagate the update to fallback_backend_addresses.
   if (glb_policy->serverlist == NULL) {
-    // If a non-empty serverlist hasn't been received from the balancer,
-    // propagate the update to fallback_backend_addresses.
     fallback_update_locked(exec_ctx, glb_policy, addresses);
-  } else if (glb_policy->updating_lb_channel) {
-    // If we have recieved serverlist from the balancer, we need to defer update
-    // when there is an in-progress one.
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
-      gpr_log(GPR_INFO,
-              "Update already in progress for grpclb %p. Deferring update.",
-              (void *)glb_policy);
-    }
-    if (glb_policy->pending_update_args != NULL) {
-      grpc_channel_args_destroy(exec_ctx,
-                                glb_policy->pending_update_args->args);
-      gpr_free(glb_policy->pending_update_args);
-    }
-    glb_policy->pending_update_args = (grpc_lb_policy_args *)gpr_zalloc(
-        sizeof(*glb_policy->pending_update_args));
-    glb_policy->pending_update_args->client_channel_factory =
-        args->client_channel_factory;
-    glb_policy->pending_update_args->args = grpc_channel_args_copy(args->args);
-    glb_policy->pending_update_args->combiner = args->combiner;
-    return;
   }
-
-  glb_policy->updating_lb_channel = true;
   GPR_ASSERT(glb_policy->lb_channel != NULL);
+  // Propagate updates to the LB channel (pick_first) through the fake
+  // resolver.
   grpc_channel_args *lb_channel_args = build_lb_channel_args(
       exec_ctx, addresses, glb_policy->response_generator, args->args);
-  /* Propagate updates to the LB channel (pick first) through the fake resolver
-   */
   grpc_fake_resolver_response_generator_set_response(
       exec_ctx, glb_policy->response_generator, lb_channel_args);
   grpc_channel_args_destroy(exec_ctx, lb_channel_args);
-
+  // Start watching the LB channel connectivity for connection, if not
+  // already doing so.
   if (!glb_policy->watching_lb_channel) {
-    // Watch the LB channel connectivity for connection.
     glb_policy->lb_channel_connectivity = grpc_channel_check_connectivity_state(
         glb_policy->lb_channel, true /* try to connect */);
     grpc_channel_element *client_channel_elem = grpc_channel_stack_last_element(
@@ -1847,18 +1809,10 @@ static void glb_lb_channel_on_connectivity_changed_cb(grpc_exec_ctx *exec_ctx,
     /* fallthrough */
     case GRPC_CHANNEL_READY:
       if (glb_policy->lb_call != NULL) {
-        glb_policy->updating_lb_channel = false;
         glb_policy->updating_lb_call = true;
         grpc_call_cancel(glb_policy->lb_call, NULL);
-        // lb_on_server_status_received will pick up the cancel and reinit
+        // lb_on_server_status_received() will pick up the cancel and reinit
         // lb_call.
-        if (glb_policy->pending_update_args != NULL) {
-          grpc_lb_policy_args *args = glb_policy->pending_update_args;
-          glb_policy->pending_update_args = NULL;
-          glb_update_locked(exec_ctx, &glb_policy->base, args);
-          grpc_channel_args_destroy(exec_ctx, args->args);
-          gpr_free(args);
-        }
       } else if (glb_policy->started_picking && !glb_policy->shutting_down) {
         if (glb_policy->retry_timer_active) {
           grpc_timer_cancel(exec_ctx, &glb_policy->lb_call_retry_timer);
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
index c67df609fc..15c8a680b7 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
@@ -34,4 +34,4 @@ grpc_lb_policy_factory *grpc_glb_lb_factory_create();
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_H */
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.cc
index 8ef6dfc6f4..4d5fb2081c 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.cc
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.cc
@@ -299,13 +299,10 @@ int grpc_grpclb_duration_compare(const grpc_grpclb_duration *lhs,
   return 0;
 }
 
-gpr_timespec grpc_grpclb_duration_to_timespec(
-    grpc_grpclb_duration *duration_pb) {
-  gpr_timespec duration;
-  duration.tv_sec = duration_pb->has_seconds ? duration_pb->seconds : 0;
-  duration.tv_nsec = duration_pb->has_nanos ? duration_pb->nanos : 0;
-  duration.clock_type = GPR_TIMESPAN;
-  return duration;
+grpc_millis grpc_grpclb_duration_to_millis(grpc_grpclb_duration *duration_pb) {
+  return (grpc_millis)(
+      (duration_pb->has_seconds ? duration_pb->seconds : 0) * GPR_MS_PER_SEC +
+      (duration_pb->has_nanos ? duration_pb->nanos : 0) / GPR_NS_PER_MS);
 }
 
 void grpc_grpclb_initial_response_destroy(
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
index c4a98492c9..56b9c096d0 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
@@ -81,8 +81,7 @@ void grpc_grpclb_destroy_serverlist(grpc_grpclb_serverlist *serverlist);
 int grpc_grpclb_duration_compare(const grpc_grpclb_duration *lhs,
                                  const grpc_grpclb_duration *rhs);
 
-gpr_timespec grpc_grpclb_duration_to_timespec(
-    grpc_grpclb_duration *duration_pb);
+grpc_millis grpc_grpclb_duration_to_millis(grpc_grpclb_duration *duration_pb);
 
 /** Destroy \a initial_response */
 void grpc_grpclb_initial_response_destroy(
diff --git a/src/core/ext/filters/client_channel/lb_policy_factory.h b/src/core/ext/filters/client_channel/lb_policy_factory.h
index 69bcba4232..8790ffdda3 100644
--- a/src/core/ext/filters/client_channel/lb_policy_factory.h
+++ b/src/core/ext/filters/client_channel/lb_policy_factory.h
@@ -138,4 +138,4 @@ grpc_lb_policy *grpc_lb_policy_factory_create_lb_policy(
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_FACTORY_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_FACTORY_H */
diff --git a/src/core/ext/filters/client_channel/lb_policy_registry.h b/src/core/ext/filters/client_channel/lb_policy_registry.h
index 0867844c37..55154cb02a 100644
--- a/src/core/ext/filters/client_channel/lb_policy_registry.h
+++ b/src/core/ext/filters/client_channel/lb_policy_registry.h
@@ -45,4 +45,4 @@ grpc_lb_policy *grpc_lb_policy_create(grpc_exec_ctx *exec_ctx, const char *name,
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_REGISTRY_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_REGISTRY_H */
diff --git a/src/core/ext/filters/client_channel/parse_address.h b/src/core/ext/filters/client_channel/parse_address.h
index 742df380b7..27d06a1cb3 100644
--- a/src/core/ext/filters/client_channel/parse_address.h
+++ b/src/core/ext/filters/client_channel/parse_address.h
@@ -53,4 +53,4 @@ bool grpc_parse_ipv6_hostport(const char *hostport, grpc_resolved_address *addr,
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PARSE_ADDRESS_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PARSE_ADDRESS_H */
diff --git a/src/core/ext/filters/client_channel/proxy_mapper.h b/src/core/ext/filters/client_channel/proxy_mapper.h
index 1325a9f1f6..bb8259f854 100644
--- a/src/core/ext/filters/client_channel/proxy_mapper.h
+++ b/src/core/ext/filters/client_channel/proxy_mapper.h
@@ -79,4 +79,4 @@ void grpc_proxy_mapper_destroy(grpc_proxy_mapper* mapper);
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_H */
diff --git a/src/core/ext/filters/client_channel/proxy_mapper_registry.h b/src/core/ext/filters/client_channel/proxy_mapper_registry.h
index 2d389f1c21..39c607cefc 100644
--- a/src/core/ext/filters/client_channel/proxy_mapper_registry.h
+++ b/src/core/ext/filters/client_channel/proxy_mapper_registry.h
@@ -49,4 +49,4 @@ bool grpc_proxy_mappers_map_address(grpc_exec_ctx* exec_ctx,
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_REGISTRY_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PROXY_MAPPER_REGISTRY_H */
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 69f5877b00..5f7ab987cb 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
@@ -32,13 +32,13 @@
 #include "src/core/ext/filters/client_channel/lb_policy_registry.h"
 #include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h"
 #include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/lib/backoff/backoff.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/gethostname.h"
 #include "src/core/lib/iomgr/resolve_address.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/json/json.h"
-#include "src/core/lib/support/backoff.h"
 #include "src/core/lib/support/env.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/transport/service_config.h"
@@ -89,7 +89,7 @@ typedef struct {
   bool have_retry_timer;
   grpc_timer retry_timer;
   /** retry backoff state */
-  gpr_backoff backoff_state;
+  grpc_backoff backoff_state;
 
   /** currently resolving addresses */
   grpc_lb_addresses *lb_addresses;
@@ -137,7 +137,7 @@ static void dns_ares_channel_saw_error_locked(grpc_exec_ctx *exec_ctx,
                                               grpc_resolver *resolver) {
   ares_dns_resolver *r = (ares_dns_resolver *)resolver;
   if (!r->resolving) {
-    gpr_backoff_reset(&r->backoff_state);
+    grpc_backoff_reset(&r->backoff_state);
     dns_ares_start_resolving_locked(exec_ctx, r);
   }
 }
@@ -271,22 +271,20 @@ static void dns_ares_on_resolved_locked(grpc_exec_ctx *exec_ctx, void *arg,
   } else {
     const char *msg = grpc_error_string(error);
     gpr_log(GPR_DEBUG, "dns resolution failed: %s", msg);
-    gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
-    gpr_timespec next_try = gpr_backoff_step(&r->backoff_state, now);
-    gpr_timespec timeout = gpr_time_sub(next_try, now);
+    grpc_millis next_try = grpc_backoff_step(exec_ctx, &r->backoff_state);
+    grpc_millis timeout = next_try - grpc_exec_ctx_now(exec_ctx);
     gpr_log(GPR_INFO, "dns resolution failed (will retry): %s",
             grpc_error_string(error));
     GPR_ASSERT(!r->have_retry_timer);
     r->have_retry_timer = true;
     GRPC_RESOLVER_REF(&r->base, "retry-timer");
-    if (gpr_time_cmp(timeout, gpr_time_0(timeout.clock_type)) > 0) {
-      gpr_log(GPR_DEBUG, "retrying in %" PRId64 ".%09d seconds", timeout.tv_sec,
-              timeout.tv_nsec);
+    if (timeout > 0) {
+      gpr_log(GPR_DEBUG, "retrying in %" PRIdPTR " milliseconds", timeout);
     } else {
       gpr_log(GPR_DEBUG, "retrying immediately");
     }
     grpc_timer_init(exec_ctx, &r->retry_timer, next_try,
-                    &r->dns_ares_on_retry_timer_locked, now);
+                    &r->dns_ares_on_retry_timer_locked);
   }
   if (r->resolved_result != NULL) {
     grpc_channel_args_destroy(exec_ctx, r->resolved_result);
@@ -307,7 +305,7 @@ static void dns_ares_next_locked(grpc_exec_ctx *exec_ctx,
   r->next_completion = on_complete;
   r->target_result = target_result;
   if (r->resolved_version == 0 && !r->resolving) {
-    gpr_backoff_reset(&r->backoff_state);
+    grpc_backoff_reset(&r->backoff_state);
     dns_ares_start_resolving_locked(exec_ctx, r);
   } else {
     dns_ares_maybe_finish_next_locked(exec_ctx, r);
@@ -381,11 +379,11 @@ static grpc_resolver *dns_ares_create(grpc_exec_ctx *exec_ctx,
     grpc_pollset_set_add_pollset_set(exec_ctx, r->interested_parties,
                                      args->pollset_set);
   }
-  gpr_backoff_init(&r->backoff_state, GRPC_DNS_INITIAL_CONNECT_BACKOFF_SECONDS,
-                   GRPC_DNS_RECONNECT_BACKOFF_MULTIPLIER,
-                   GRPC_DNS_RECONNECT_JITTER,
-                   GRPC_DNS_MIN_CONNECT_TIMEOUT_SECONDS * 1000,
-                   GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
+  grpc_backoff_init(&r->backoff_state, GRPC_DNS_INITIAL_CONNECT_BACKOFF_SECONDS,
+                    GRPC_DNS_RECONNECT_BACKOFF_MULTIPLIER,
+                    GRPC_DNS_RECONNECT_JITTER,
+                    GRPC_DNS_MIN_CONNECT_TIMEOUT_SECONDS * 1000,
+                    GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
   GRPC_CLOSURE_INIT(&r->dns_ares_on_retry_timer_locked,
                     dns_ares_on_retry_timer_locked, r,
                     grpc_combiner_scheduler(r->base.combiner));
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 1c093d0ad2..e669b6dfc7 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
@@ -27,11 +27,11 @@
 
 #include "src/core/ext/filters/client_channel/lb_policy_registry.h"
 #include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/lib/backoff/backoff.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/resolve_address.h"
 #include "src/core/lib/iomgr/timer.h"
-#include "src/core/lib/support/backoff.h"
 #include "src/core/lib/support/env.h"
 #include "src/core/lib/support/string.h"
 
@@ -70,7 +70,7 @@ typedef struct {
   grpc_timer retry_timer;
   grpc_closure on_retry;
   /** retry backoff state */
-  gpr_backoff backoff_state;
+  grpc_backoff backoff_state;
 
   /** currently resolving addresses */
   grpc_resolved_addresses *addresses;
@@ -113,7 +113,7 @@ static void dns_channel_saw_error_locked(grpc_exec_ctx *exec_ctx,
                                          grpc_resolver *resolver) {
   dns_resolver *r = (dns_resolver *)resolver;
   if (!r->resolving) {
-    gpr_backoff_reset(&r->backoff_state);
+    grpc_backoff_reset(&r->backoff_state);
     dns_start_resolving_locked(exec_ctx, r);
   }
 }
@@ -126,7 +126,7 @@ static void dns_next_locked(grpc_exec_ctx *exec_ctx, grpc_resolver *resolver,
   r->next_completion = on_complete;
   r->target_result = target_result;
   if (r->resolved_version == 0 && !r->resolving) {
-    gpr_backoff_reset(&r->backoff_state);
+    grpc_backoff_reset(&r->backoff_state);
     dns_start_resolving_locked(exec_ctx, r);
   } else {
     dns_maybe_finish_next_locked(exec_ctx, r);
@@ -153,6 +153,9 @@ static void dns_on_resolved_locked(grpc_exec_ctx *exec_ctx, void *arg,
   grpc_channel_args *result = NULL;
   GPR_ASSERT(r->resolving);
   r->resolving = false;
+  GRPC_ERROR_REF(error);
+  error = grpc_error_set_str(error, GRPC_ERROR_STR_TARGET_ADDRESS,
+                             grpc_slice_from_copied_string(r->name_to_resolve));
   if (r->addresses != NULL) {
     grpc_lb_addresses *addresses = grpc_lb_addresses_create(
         r->addresses->naddrs, NULL /* user_data_vtable */);
@@ -167,23 +170,21 @@ static void dns_on_resolved_locked(grpc_exec_ctx *exec_ctx, void *arg,
     grpc_resolved_addresses_destroy(r->addresses);
     grpc_lb_addresses_destroy(exec_ctx, addresses);
   } else {
-    gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
-    gpr_timespec next_try = gpr_backoff_step(&r->backoff_state, now);
-    gpr_timespec timeout = gpr_time_sub(next_try, now);
+    grpc_millis next_try = grpc_backoff_step(exec_ctx, &r->backoff_state);
+    grpc_millis timeout = next_try - grpc_exec_ctx_now(exec_ctx);
     gpr_log(GPR_INFO, "dns resolution failed (will retry): %s",
             grpc_error_string(error));
     GPR_ASSERT(!r->have_retry_timer);
     r->have_retry_timer = true;
     GRPC_RESOLVER_REF(&r->base, "retry-timer");
-    if (gpr_time_cmp(timeout, gpr_time_0(timeout.clock_type)) > 0) {
-      gpr_log(GPR_DEBUG, "retrying in %" PRId64 ".%09d seconds", timeout.tv_sec,
-              timeout.tv_nsec);
+    if (timeout > 0) {
+      gpr_log(GPR_DEBUG, "retrying in %" PRIdPTR " milliseconds", timeout);
     } else {
       gpr_log(GPR_DEBUG, "retrying immediately");
     }
     GRPC_CLOSURE_INIT(&r->on_retry, dns_on_retry_timer_locked, r,
                       grpc_combiner_scheduler(r->base.combiner));
-    grpc_timer_init(exec_ctx, &r->retry_timer, next_try, &r->on_retry, now);
+    grpc_timer_init(exec_ctx, &r->retry_timer, next_try, &r->on_retry);
   }
   if (r->resolved_result != NULL) {
     grpc_channel_args_destroy(exec_ctx, r->resolved_result);
@@ -191,6 +192,7 @@ static void dns_on_resolved_locked(grpc_exec_ctx *exec_ctx, void *arg,
   r->resolved_result = result;
   r->resolved_version++;
   dns_maybe_finish_next_locked(exec_ctx, r);
+  GRPC_ERROR_UNREF(error);
 
   GRPC_RESOLVER_UNREF(exec_ctx, &r->base, "dns-resolving");
 }
@@ -254,11 +256,11 @@ static grpc_resolver *dns_create(grpc_exec_ctx *exec_ctx,
     grpc_pollset_set_add_pollset_set(exec_ctx, r->interested_parties,
                                      args->pollset_set);
   }
-  gpr_backoff_init(&r->backoff_state, GRPC_DNS_INITIAL_CONNECT_BACKOFF_SECONDS,
-                   GRPC_DNS_RECONNECT_BACKOFF_MULTIPLIER,
-                   GRPC_DNS_RECONNECT_JITTER,
-                   GRPC_DNS_MIN_CONNECT_TIMEOUT_SECONDS * 1000,
-                   GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
+  grpc_backoff_init(&r->backoff_state, GRPC_DNS_INITIAL_CONNECT_BACKOFF_SECONDS,
+                    GRPC_DNS_RECONNECT_BACKOFF_MULTIPLIER,
+                    GRPC_DNS_RECONNECT_JITTER,
+                    GRPC_DNS_MIN_CONNECT_TIMEOUT_SECONDS * 1000,
+                    GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
   return &r->base;
 }
 
diff --git a/src/core/ext/filters/client_channel/resolver_factory.h b/src/core/ext/filters/client_channel/resolver_factory.h
index 6e533e3248..c8b2c58db3 100644
--- a/src/core/ext/filters/client_channel/resolver_factory.h
+++ b/src/core/ext/filters/client_channel/resolver_factory.h
@@ -75,4 +75,4 @@ char *grpc_resolver_factory_get_default_authority(
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FACTORY_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FACTORY_H */
diff --git a/src/core/ext/filters/client_channel/resolver_registry.h b/src/core/ext/filters/client_channel/resolver_registry.h
index eb08d887b1..06d0b99a35 100644
--- a/src/core/ext/filters/client_channel/resolver_registry.h
+++ b/src/core/ext/filters/client_channel/resolver_registry.h
@@ -74,4 +74,4 @@ char *grpc_resolver_factory_add_default_prefix_if_needed(
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_REGISTRY_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_REGISTRY_H */
diff --git a/src/core/ext/filters/client_channel/retry_throttle.h b/src/core/ext/filters/client_channel/retry_throttle.h
index 3b849475b9..399383df78 100644
--- a/src/core/ext/filters/client_channel/retry_throttle.h
+++ b/src/core/ext/filters/client_channel/retry_throttle.h
@@ -55,4 +55,4 @@ grpc_server_retry_throttle_data* grpc_retry_throttle_map_get_data_for_server(
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RETRY_THROTTLE_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RETRY_THROTTLE_H */
diff --git a/src/core/ext/filters/client_channel/subchannel.cc b/src/core/ext/filters/client_channel/subchannel.cc
index bff5001d69..5710a22178 100644
--- a/src/core/ext/filters/client_channel/subchannel.cc
+++ b/src/core/ext/filters/client_channel/subchannel.cc
@@ -31,6 +31,7 @@
 #include "src/core/ext/filters/client_channel/proxy_mapper_registry.h"
 #include "src/core/ext/filters/client_channel/subchannel_index.h"
 #include "src/core/ext/filters/client_channel/uri_parser.h"
+#include "src/core/lib/backoff/backoff.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/connected_channel.h"
 #include "src/core/lib/debug/stats.h"
@@ -38,7 +39,6 @@
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/slice/slice_internal.h"
-#include "src/core/lib/support/backoff.h"
 #include "src/core/lib/surface/channel.h"
 #include "src/core/lib/surface/channel_init.h"
 #include "src/core/lib/transport/connectivity_state.h"
@@ -118,9 +118,9 @@ struct grpc_subchannel {
   external_state_watcher root_external_state_watcher;
 
   /** next connect attempt time */
-  gpr_timespec next_attempt;
+  grpc_millis next_attempt;
   /** backoff state */
-  gpr_backoff backoff_state;
+  grpc_backoff backoff_state;
   /** do we have an active alarm? */
   bool have_alarm;
   /** have we started the backoff loop */
@@ -364,7 +364,7 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
       }
     }
   }
-  gpr_backoff_init(
+  grpc_backoff_init(
       &c->backoff_state, initial_backoff_ms,
       fixed_reconnect_backoff ? 1.0
                               : GRPC_SUBCHANNEL_RECONNECT_BACKOFF_MULTIPLIER,
@@ -428,8 +428,7 @@ static void on_alarm(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
   }
   if (error == GRPC_ERROR_NONE) {
     gpr_log(GPR_INFO, "Failed to connect to channel, retrying");
-    c->next_attempt =
-        gpr_backoff_step(&c->backoff_state, gpr_now(GPR_CLOCK_MONOTONIC));
+    c->next_attempt = grpc_backoff_step(exec_ctx, &c->backoff_state);
     continue_connect_locked(exec_ctx, c);
     gpr_mu_unlock(&c->mu);
   } else {
@@ -464,24 +463,22 @@ static void maybe_start_connecting_locked(grpc_exec_ctx *exec_ctx,
   c->connecting = true;
   GRPC_SUBCHANNEL_WEAK_REF(c, "connecting");
 
-  gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
   if (!c->backoff_begun) {
     c->backoff_begun = true;
-    c->next_attempt = gpr_backoff_begin(&c->backoff_state, now);
+    c->next_attempt = grpc_backoff_begin(exec_ctx, &c->backoff_state);
     continue_connect_locked(exec_ctx, c);
   } else {
     GPR_ASSERT(!c->have_alarm);
     c->have_alarm = true;
-    gpr_timespec time_til_next = gpr_time_sub(c->next_attempt, now);
-    if (gpr_time_cmp(time_til_next, gpr_time_0(time_til_next.clock_type)) <=
-        0) {
+    const grpc_millis time_til_next =
+        c->next_attempt - grpc_exec_ctx_now(exec_ctx);
+    if (time_til_next <= 0) {
       gpr_log(GPR_INFO, "Retry immediately");
     } else {
-      gpr_log(GPR_INFO, "Retry in %" PRId64 ".%09d seconds",
-              time_til_next.tv_sec, time_til_next.tv_nsec);
+      gpr_log(GPR_INFO, "Retry in %" PRIdPTR " milliseconds", time_til_next);
     }
     GRPC_CLOSURE_INIT(&c->on_alarm, on_alarm, c, grpc_schedule_on_exec_ctx);
-    grpc_timer_init(exec_ctx, &c->alarm, c->next_attempt, &c->on_alarm, now);
+    grpc_timer_init(exec_ctx, &c->alarm, c->next_attempt, &c->on_alarm);
   }
 }
 
diff --git a/src/core/ext/filters/client_channel/subchannel.h b/src/core/ext/filters/client_channel/subchannel.h
index c67ff97b0b..46b29f1fe0 100644
--- a/src/core/ext/filters/client_channel/subchannel.h
+++ b/src/core/ext/filters/client_channel/subchannel.h
@@ -107,7 +107,7 @@ typedef struct {
   grpc_polling_entity *pollent;
   grpc_slice path;
   gpr_timespec start_time;
-  gpr_timespec deadline;
+  grpc_millis deadline;
   gpr_arena *arena;
   grpc_call_context_element *context;
   grpc_call_combiner *call_combiner;
diff --git a/src/core/ext/filters/client_channel/subchannel_index.h b/src/core/ext/filters/client_channel/subchannel_index.h
index 09bac3592c..05c3878379 100644
--- a/src/core/ext/filters/client_channel/subchannel_index.h
+++ b/src/core/ext/filters/client_channel/subchannel_index.h
@@ -86,4 +86,4 @@ void grpc_subchannel_index_test_only_set_force_creation(bool force_creation);
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H */
diff --git a/src/core/ext/filters/client_channel/uri_parser.h b/src/core/ext/filters/client_channel/uri_parser.h
index 43e8ae64e0..e78da5928b 100644
--- a/src/core/ext/filters/client_channel/uri_parser.h
+++ b/src/core/ext/filters/client_channel/uri_parser.h
@@ -55,4 +55,4 @@ void grpc_uri_destroy(grpc_uri *uri);
 }
 #endif
 
-#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_URI_PARSER_H */
\ No newline at end of file
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_URI_PARSER_H */