1 files changed, 30 insertions, 21 deletions
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
index d6201f2387..a190c2075d 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
@@ -50,28 +50,37 @@ grpc_channel *grpc_lb_policy_grpclb_create_lb_channel(
   return lb_channel;
 }
 
-grpc_channel_args *get_lb_channel_args(grpc_exec_ctx *exec_ctx,
-                                       grpc_slice_hash_table *targets_info,
-                                       const grpc_channel_args *args) {
-  /* We strip out the channel arg for the LB policy name, since we want
-   * to use the default (pick_first) in this case.
+grpc_channel_args *grpc_lb_policy_grpclb_build_lb_channel_args(
+    grpc_exec_ctx *exec_ctx, grpc_slice_hash_table *targets_info,
+    grpc_fake_resolver_response_generator *response_generator,
+    const grpc_channel_args *args) {
+  const grpc_arg to_add[] = {
+      grpc_fake_resolver_response_generator_arg(response_generator)};
+  /* We remove:
    *
-   * We also strip out the channel arg for the resolved addresses, since
-   * that will be generated by the name resolver used in the LB channel.
-   * Note that the LB channel will use the sockaddr resolver, so this
-   * won't actually generate a query to DNS (or some other name service).
-   * However, the addresses returned by the sockaddr resolver will have
-   * is_balancer=false, whereas our own addresses have is_balancer=true.
-   * We need the LB channel to return addresses with is_balancer=false
-   * so that it does not wind up recursively using the grpclb LB policy,
-   * as per the special case logic in client_channel.c.
+   * - The channel arg for the LB policy name, since we want to use the default
+   *   (pick_first) in this case.
    *
-   * Lastly, we also strip out the channel arg for the server URI,
-   * since that will be different for the LB channel than for the parent
-   * channel (the client channel factory will re-add this arg with
-   * the right value). */
+   * - The channel arg for the resolved addresses, since that will be generated
+   *   by the name resolver used in the LB channel.  Note that the LB channel
+   *   will use the fake resolver, so this won't actually generate a query
+   *   to DNS (or some other name service).  However, the addresses returned by
+   *   the fake resolver will have is_balancer=false, whereas our own
+   *   addresses have is_balancer=true.  We need the LB channel to return
+   *   addresses with is_balancer=false so that it does not wind up recursively
+   *   using the grpclb LB policy, as per the special case logic in
+   *   client_channel.c.
+   *
+   * - The channel arg for the server URI, since that will be different for the
+   *   LB channel than for the parent channel (the client channel factory will
+   *   re-add this arg with the right value).
+   *
+   * - The fake resolver generator, because we are replacing it with the one
+   *   from the grpclb policy, used to propagate updates to the LB channel. */
   static const char *keys_to_remove[] = {
-      GRPC_ARG_LB_POLICY_NAME, GRPC_ARG_LB_ADDRESSES, GRPC_ARG_SERVER_URI};
-  return grpc_channel_args_copy_and_remove(args, keys_to_remove,
-                                           GPR_ARRAY_SIZE(keys_to_remove));
+      GRPC_ARG_LB_POLICY_NAME, GRPC_ARG_LB_ADDRESSES, GRPC_ARG_SERVER_URI,
+      GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR};
+  return grpc_channel_args_copy_and_add_and_remove(
+      args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), to_add,
+      GPR_ARRAY_SIZE(to_add));
 }