1 files changed, 32 insertions, 37 deletions

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 04379975e1..fecf2bfebc 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
@@ -96,23 +96,23 @@ static void grpc_ares_request_ref(grpc_ares_request *r) {
   gpr_ref(&r->pending_queries);
 }
 
-static void grpc_ares_request_unref(grpc_exec_ctx *exec_ctx,
-                                    grpc_ares_request *r) {
+static void grpc_ares_request_unref(grpc_ares_request *r) {
   /* If there are no pending queries, invoke on_done callback and destroy the
      request */
   if (gpr_unref(&r->pending_queries)) {
     /* TODO(zyc): Sort results with RFC6724 before invoking on_done. */
-    if (exec_ctx == NULL) {
+    if (/*might be dangerous */ exec_ctx == NULL) {
       /* A new exec_ctx is created here, as the c-ares interface does not
          provide one in ares_host_callback. It's safe to schedule on_done with
          the newly created exec_ctx, since the caller has been warned not to
          acquire locks in on_done. ares_dns_resolver is using combiner to
          protect resources needed by on_done. */
-      grpc_exec_ctx new_exec_ctx = GRPC_EXEC_CTX_INIT;
-      GRPC_CLOSURE_SCHED(&new_exec_ctx, r->on_done, r->error);
-      grpc_exec_ctx_finish(&new_exec_ctx);
+      ExecCtx _local_exec_ctx;
+      GRPC_CLOSURE_SCHED(/* might be dangerous &new_exec_ctx, */ r->on_done,
+                         r->error);
+      grpc_exec_ctx_finish(/*&new_exec_ctx*/);
     } else {
-      GRPC_CLOSURE_SCHED(exec_ctx, r->on_done, r->error);
+      GRPC_CLOSURE_SCHED(r->on_done, r->error);
     }
     gpr_mu_destroy(&r->mu);
     grpc_ares_ev_driver_destroy(r->ev_driver);
@@ -133,9 +133,8 @@ static grpc_ares_hostbyname_request *create_hostbyname_request(
   return hr;
 }
 
-static void destroy_hostbyname_request(grpc_exec_ctx *exec_ctx,
-                                       grpc_ares_hostbyname_request *hr) {
-  grpc_ares_request_unref(exec_ctx, hr->parent_request);
+static void destroy_hostbyname_request(grpc_ares_hostbyname_request *hr) {
+  grpc_ares_request_unref(hr->parent_request);
   gpr_free(hr->host);
   gpr_free(hr);
 }
@@ -220,13 +219,13 @@ static void on_hostbyname_done_cb(void *arg, int status, int timeouts,
     }
   }
   gpr_mu_unlock(&r->mu);
-  destroy_hostbyname_request(NULL, hr);
+  destroy_hostbyname_request(/* might be dangerous */ hr);
 }
 
 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;
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  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");
@@ -246,7 +245,7 @@ static void on_srv_query_done_cb(void *arg, int status, int timeouts,
             r, srv_it->host, htons(srv_it->port), true /* is_balancer */);
         ares_gethostbyname(*channel, hr->host, AF_INET, on_hostbyname_done_cb,
                            hr);
-        grpc_ares_ev_driver_start(&exec_ctx, r->ev_driver);
+        grpc_ares_ev_driver_start(r->ev_driver);
       }
     }
     if (reply != NULL) {
@@ -264,8 +263,8 @@ static void on_srv_query_done_cb(void *arg, int status, int timeouts,
       r->error = grpc_error_add_child(error, r->error);
     }
   }
-  grpc_ares_request_unref(&exec_ctx, r);
-  grpc_exec_ctx_finish(&exec_ctx);
+  grpc_ares_request_unref(r);
+  grpc_exec_ctx_finish();
 }
 
 static const char g_service_config_attribute_prefix[] = "grpc_config=";
@@ -323,14 +322,13 @@ fail:
   }
 done:
   gpr_mu_unlock(&r->mu);
-  grpc_ares_request_unref(NULL, r);
+  grpc_ares_request_unref(r);
 }
 
 static grpc_ares_request *grpc_dns_lookup_ares_impl(
-    grpc_exec_ctx *exec_ctx, const char *dns_server, const char *name,
-    const char *default_port, grpc_pollset_set *interested_parties,
-    grpc_closure *on_done, grpc_lb_addresses **addrs, bool check_grpclb,
-    char **service_config_json) {
+    const char *dns_server, const char *name, const char *default_port,
+    grpc_pollset_set *interested_parties, grpc_closure *on_done,
+    grpc_lb_addresses **addrs, bool check_grpclb, char **service_config_json) {
   grpc_error *error = GRPC_ERROR_NONE;
   grpc_ares_hostbyname_request *hr = NULL;
   grpc_ares_request *r = NULL;
@@ -434,28 +432,28 @@ static grpc_ares_request *grpc_dns_lookup_ares_impl(
     ares_search(*channel, hr->host, ns_c_in, ns_t_txt, on_txt_done_cb, r);
   }
   /* TODO(zyc): Handle CNAME records here. */
-  grpc_ares_ev_driver_start(exec_ctx, r->ev_driver);
-  grpc_ares_request_unref(exec_ctx, r);
+  grpc_ares_ev_driver_start(r->ev_driver);
+  grpc_ares_request_unref(r);
   gpr_free(host);
   gpr_free(port);
   return r;
 
 error_cleanup:
-  GRPC_CLOSURE_SCHED(exec_ctx, on_done, error);
+  GRPC_CLOSURE_SCHED(on_done, error);
   gpr_free(host);
   gpr_free(port);
   return NULL;
 }
 
 grpc_ares_request *(*grpc_dns_lookup_ares)(
-    grpc_exec_ctx *exec_ctx, const char *dns_server, const char *name,
-    const char *default_port, grpc_pollset_set *interested_parties,
-    grpc_closure *on_done, grpc_lb_addresses **addrs, bool check_grpclb,
+    const char *dns_server, const char *name, const char *default_port,
+    grpc_pollset_set *interested_parties, grpc_closure *on_done,
+    grpc_lb_addresses **addrs, bool check_grpclb,
     char **service_config_json) = grpc_dns_lookup_ares_impl;
 
-void grpc_cancel_ares_request(grpc_exec_ctx *exec_ctx, grpc_ares_request *r) {
+void grpc_cancel_ares_request(grpc_ares_request *r) {
   if (grpc_dns_lookup_ares == grpc_dns_lookup_ares_impl) {
-    grpc_ares_ev_driver_shutdown(exec_ctx, r->ev_driver);
+    grpc_ares_ev_driver_shutdown(r->ev_driver);
   }
 }
 
@@ -498,8 +496,7 @@ typedef struct grpc_resolve_address_ares_request {
   grpc_closure on_dns_lookup_done;
 } grpc_resolve_address_ares_request;
 
-static void on_dns_lookup_done_cb(grpc_exec_ctx *exec_ctx, void *arg,
-                                  grpc_error *error) {
+static void on_dns_lookup_done_cb(void *arg, grpc_error *error) {
   grpc_resolve_address_ares_request *r =
       (grpc_resolve_address_ares_request *)arg;
   grpc_resolved_addresses **resolved_addresses = r->addrs_out;
@@ -517,14 +514,12 @@ static void on_dns_lookup_done_cb(grpc_exec_ctx *exec_ctx, void *arg,
              &r->lb_addrs->addresses[i].address, sizeof(grpc_resolved_address));
     }
   }
-  GRPC_CLOSURE_SCHED(exec_ctx, r->on_resolve_address_done,
-                     GRPC_ERROR_REF(error));
-  grpc_lb_addresses_destroy(exec_ctx, r->lb_addrs);
+  GRPC_CLOSURE_SCHED(r->on_resolve_address_done, GRPC_ERROR_REF(error));
+  grpc_lb_addresses_destroy(r->lb_addrs);
   gpr_free(r);
 }
 
-static void grpc_resolve_address_ares_impl(grpc_exec_ctx *exec_ctx,
-                                           const char *name,
+static void grpc_resolve_address_ares_impl(const char *name,
                                            const char *default_port,
                                            grpc_pollset_set *interested_parties,
                                            grpc_closure *on_done,
@@ -536,14 +531,14 @@ static void grpc_resolve_address_ares_impl(grpc_exec_ctx *exec_ctx,
   r->on_resolve_address_done = on_done;
   GRPC_CLOSURE_INIT(&r->on_dns_lookup_done, on_dns_lookup_done_cb, r,
                     grpc_schedule_on_exec_ctx);
-  grpc_dns_lookup_ares(exec_ctx, NULL /* dns_server */, name, default_port,
+  grpc_dns_lookup_ares(NULL /* dns_server */, name, default_port,
                        interested_parties, &r->on_dns_lookup_done, &r->lb_addrs,
                        false /* check_grpclb */,
                        NULL /* service_config_json */);
 }
 
 void (*grpc_resolve_address_ares)(
-    grpc_exec_ctx *exec_ctx, const char *name, const char *default_port,
+    const char *name, const char *default_port,
     grpc_pollset_set *interested_parties, grpc_closure *on_done,
     grpc_resolved_addresses **addrs) = grpc_resolve_address_ares_impl;