Removing instances of exec_ctx being passed around in functions in

src/core. exec_ctx is now a thread_local pointer of type ExecCtx instead of
grpc_exec_ctx which is initialized whenever ExecCtx is instantiated. ExecCtx
also keeps track of the previous exec_ctx so that nesting of exec_ctx is
allowed. This means that there is only one exec_ctx being used at any
time. Also, grpc_exec_ctx_finish is called in the destructor of the
object, and the previous exec_ctx is restored to avoid breaking current
functionality. The code still explicitly calls grpc_exec_ctx_finish
because removing all such instances causes the code to break.

1 files changed, 35 insertions, 47 deletions

diff --git a/src/core/ext/filters/client_channel/http_connect_handshaker.cc b/src/core/ext/filters/client_channel/http_connect_handshaker.cc
index 418bb41ef6..14b3836b90 100644
--- a/src/core/ext/filters/client_channel/http_connect_handshaker.cc
+++ b/src/core/ext/filters/client_channel/http_connect_handshaker.cc
@@ -61,19 +61,17 @@ typedef struct http_connect_handshaker {
 } http_connect_handshaker;
 
 // Unref and clean up handshaker.
-static void http_connect_handshaker_unref(grpc_exec_ctx* exec_ctx,
-                                          http_connect_handshaker* handshaker) {
+static void http_connect_handshaker_unref(http_connect_handshaker* handshaker) {
   if (gpr_unref(&handshaker->refcount)) {
     gpr_mu_destroy(&handshaker->mu);
     if (handshaker->endpoint_to_destroy != NULL) {
-      grpc_endpoint_destroy(exec_ctx, handshaker->endpoint_to_destroy);
+      grpc_endpoint_destroy(handshaker->endpoint_to_destroy);
     }
     if (handshaker->read_buffer_to_destroy != NULL) {
-      grpc_slice_buffer_destroy_internal(exec_ctx,
-                                         handshaker->read_buffer_to_destroy);
+      grpc_slice_buffer_destroy_internal(handshaker->read_buffer_to_destroy);
       gpr_free(handshaker->read_buffer_to_destroy);
     }
-    grpc_slice_buffer_destroy_internal(exec_ctx, &handshaker->write_buffer);
+    grpc_slice_buffer_destroy_internal(&handshaker->write_buffer);
     grpc_http_parser_destroy(&handshaker->http_parser);
     grpc_http_response_destroy(&handshaker->http_response);
     gpr_free(handshaker);
@@ -83,19 +81,18 @@ static void http_connect_handshaker_unref(grpc_exec_ctx* exec_ctx,
 // Set args fields to NULL, saving the endpoint and read buffer for
 // later destruction.
 static void cleanup_args_for_failure_locked(
-    grpc_exec_ctx* exec_ctx, http_connect_handshaker* handshaker) {
+    http_connect_handshaker* handshaker) {
   handshaker->endpoint_to_destroy = handshaker->args->endpoint;
   handshaker->args->endpoint = NULL;
   handshaker->read_buffer_to_destroy = handshaker->args->read_buffer;
   handshaker->args->read_buffer = NULL;
-  grpc_channel_args_destroy(exec_ctx, handshaker->args->args);
+  grpc_channel_args_destroy(handshaker->args->args);
   handshaker->args->args = NULL;
 }
 
 // If the handshake failed or we're shutting down, clean up and invoke the
 // callback with the error.
-static void handshake_failed_locked(grpc_exec_ctx* exec_ctx,
-                                    http_connect_handshaker* handshaker,
+static void handshake_failed_locked(http_connect_handshaker* handshaker,
                                     grpc_error* error) {
   if (error == GRPC_ERROR_NONE) {
     // If we were shut down after an endpoint operation succeeded but
@@ -108,34 +105,32 @@ static void handshake_failed_locked(grpc_exec_ctx* exec_ctx,
     // before destroying them, even if we know that there are no
     // pending read/write callbacks.  This should be fixed, at which
     // point this can be removed.
-    grpc_endpoint_shutdown(exec_ctx, handshaker->args->endpoint,
-                           GRPC_ERROR_REF(error));
+    grpc_endpoint_shutdown(handshaker->args->endpoint, GRPC_ERROR_REF(error));
     // Not shutting down, so the handshake failed.  Clean up before
     // invoking the callback.
-    cleanup_args_for_failure_locked(exec_ctx, handshaker);
+    cleanup_args_for_failure_locked(handshaker);
     // Set shutdown to true so that subsequent calls to
     // http_connect_handshaker_shutdown() do nothing.
     handshaker->shutdown = true;
   }
   // Invoke callback.
-  GRPC_CLOSURE_SCHED(exec_ctx, handshaker->on_handshake_done, error);
+  GRPC_CLOSURE_SCHED(handshaker->on_handshake_done, error);
 }
 
 // Callback invoked when finished writing HTTP CONNECT request.
-static void on_write_done(grpc_exec_ctx* exec_ctx, void* arg,
-                          grpc_error* error) {
+static void on_write_done(void* arg, grpc_error* error) {
   http_connect_handshaker* handshaker = (http_connect_handshaker*)arg;
   gpr_mu_lock(&handshaker->mu);
   if (error != GRPC_ERROR_NONE || handshaker->shutdown) {
     // If the write failed or we're shutting down, clean up and invoke the
     // callback with the error.
-    handshake_failed_locked(exec_ctx, handshaker, GRPC_ERROR_REF(error));
+    handshake_failed_locked(handshaker, GRPC_ERROR_REF(error));
     gpr_mu_unlock(&handshaker->mu);
-    http_connect_handshaker_unref(exec_ctx, handshaker);
+    http_connect_handshaker_unref(handshaker);
   } else {
     // Otherwise, read the response.
     // The read callback inherits our ref to the handshaker.
-    grpc_endpoint_read(exec_ctx, handshaker->args->endpoint,
+    grpc_endpoint_read(handshaker->args->endpoint,
                        handshaker->args->read_buffer,
                        &handshaker->response_read_closure);
     gpr_mu_unlock(&handshaker->mu);
@@ -143,14 +138,13 @@ static void on_write_done(grpc_exec_ctx* exec_ctx, void* arg,
 }
 
 // Callback invoked for reading HTTP CONNECT response.
-static void on_read_done(grpc_exec_ctx* exec_ctx, void* arg,
-                         grpc_error* error) {
+static void on_read_done(void* arg, grpc_error* error) {
   http_connect_handshaker* handshaker = (http_connect_handshaker*)arg;
   gpr_mu_lock(&handshaker->mu);
   if (error != GRPC_ERROR_NONE || handshaker->shutdown) {
     // If the read failed or we're shutting down, clean up and invoke the
     // callback with the error.
-    handshake_failed_locked(exec_ctx, handshaker, GRPC_ERROR_REF(error));
+    handshake_failed_locked(handshaker, GRPC_ERROR_REF(error));
     goto done;
   }
   // Add buffer to parser.
@@ -161,7 +155,7 @@ static void on_read_done(grpc_exec_ctx* exec_ctx, void* arg,
                                      handshaker->args->read_buffer->slices[i],
                                      &body_start_offset);
       if (error != GRPC_ERROR_NONE) {
-        handshake_failed_locked(exec_ctx, handshaker, error);
+        handshake_failed_locked(handshaker, error);
         goto done;
       }
       if (handshaker->http_parser.state == GRPC_HTTP_BODY) {
@@ -180,7 +174,7 @@ static void on_read_done(grpc_exec_ctx* exec_ctx, void* arg,
                                &handshaker->args->read_buffer->slices[i + 1],
                                handshaker->args->read_buffer->count - i - 1);
         grpc_slice_buffer_swap(handshaker->args->read_buffer, &tmp_buffer);
-        grpc_slice_buffer_destroy_internal(exec_ctx, &tmp_buffer);
+        grpc_slice_buffer_destroy_internal(&tmp_buffer);
         break;
       }
     }
@@ -197,9 +191,8 @@ static void on_read_done(grpc_exec_ctx* exec_ctx, void* arg,
   // complete (e.g., handling chunked transfer encoding or looking
   // at the Content-Length: header).
   if (handshaker->http_parser.state != GRPC_HTTP_BODY) {
-    grpc_slice_buffer_reset_and_unref_internal(exec_ctx,
-                                               handshaker->args->read_buffer);
-    grpc_endpoint_read(exec_ctx, handshaker->args->endpoint,
+    grpc_slice_buffer_reset_and_unref_internal(handshaker->args->read_buffer);
+    grpc_endpoint_read(handshaker->args->endpoint,
                        handshaker->args->read_buffer,
                        &handshaker->response_read_closure);
     gpr_mu_unlock(&handshaker->mu);
@@ -213,48 +206,44 @@ static void on_read_done(grpc_exec_ctx* exec_ctx, void* arg,
                  handshaker->http_response.status);
     error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
-    handshake_failed_locked(exec_ctx, handshaker, error);
+    handshake_failed_locked(handshaker, error);
     goto done;
   }
   // Success.  Invoke handshake-done callback.
-  GRPC_CLOSURE_SCHED(exec_ctx, handshaker->on_handshake_done, error);
+  GRPC_CLOSURE_SCHED(handshaker->on_handshake_done, error);
 done:
   // Set shutdown to true so that subsequent calls to
   // http_connect_handshaker_shutdown() do nothing.
   handshaker->shutdown = true;
   gpr_mu_unlock(&handshaker->mu);
-  http_connect_handshaker_unref(exec_ctx, handshaker);
+  http_connect_handshaker_unref(handshaker);
 }
 
 //
 // Public handshaker methods
 //
 
-static void http_connect_handshaker_destroy(grpc_exec_ctx* exec_ctx,
-                                            grpc_handshaker* handshaker_in) {
+static void http_connect_handshaker_destroy(grpc_handshaker* handshaker_in) {
   http_connect_handshaker* handshaker = (http_connect_handshaker*)handshaker_in;
-  http_connect_handshaker_unref(exec_ctx, handshaker);
+  http_connect_handshaker_unref(handshaker);
 }
 
-static void http_connect_handshaker_shutdown(grpc_exec_ctx* exec_ctx,
-                                             grpc_handshaker* handshaker_in,
+static void http_connect_handshaker_shutdown(grpc_handshaker* handshaker_in,
                                              grpc_error* why) {
   http_connect_handshaker* handshaker = (http_connect_handshaker*)handshaker_in;
   gpr_mu_lock(&handshaker->mu);
   if (!handshaker->shutdown) {
     handshaker->shutdown = true;
-    grpc_endpoint_shutdown(exec_ctx, handshaker->args->endpoint,
-                           GRPC_ERROR_REF(why));
-    cleanup_args_for_failure_locked(exec_ctx, handshaker);
+    grpc_endpoint_shutdown(handshaker->args->endpoint, GRPC_ERROR_REF(why));
+    cleanup_args_for_failure_locked(handshaker);
   }
   gpr_mu_unlock(&handshaker->mu);
   GRPC_ERROR_UNREF(why);
 }
 
 static void http_connect_handshaker_do_handshake(
-    grpc_exec_ctx* exec_ctx, grpc_handshaker* handshaker_in,
-    grpc_tcp_server_acceptor* acceptor, grpc_closure* on_handshake_done,
-    grpc_handshaker_args* args) {
+    grpc_handshaker* handshaker_in, grpc_tcp_server_acceptor* acceptor,
+    grpc_closure* on_handshake_done, grpc_handshaker_args* args) {
   http_connect_handshaker* handshaker = (http_connect_handshaker*)handshaker_in;
   // Check for HTTP CONNECT channel arg.
   // If not found, invoke on_handshake_done without doing anything.
@@ -266,7 +255,7 @@ static void http_connect_handshaker_do_handshake(
     gpr_mu_lock(&handshaker->mu);
     handshaker->shutdown = true;
     gpr_mu_unlock(&handshaker->mu);
-    GRPC_CLOSURE_SCHED(exec_ctx, on_handshake_done, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(on_handshake_done, GRPC_ERROR_NONE);
     return;
   }
   GPR_ASSERT(arg->type == GRPC_ARG_STRING);
@@ -324,7 +313,7 @@ static void http_connect_handshaker_do_handshake(
   gpr_free(header_strings);
   // Take a new ref to be held by the write callback.
   gpr_ref(&handshaker->refcount);
-  grpc_endpoint_write(exec_ctx, args->endpoint, &handshaker->write_buffer,
+  grpc_endpoint_write(args->endpoint, &handshaker->write_buffer,
                       &handshaker->request_done_closure);
   gpr_mu_unlock(&handshaker->mu);
 }
@@ -355,14 +344,13 @@ static grpc_handshaker* grpc_http_connect_handshaker_create() {
 //
 
 static void handshaker_factory_add_handshakers(
-    grpc_exec_ctx* exec_ctx, grpc_handshaker_factory* factory,
-    const grpc_channel_args* args, grpc_handshake_manager* handshake_mgr) {
+    grpc_handshaker_factory* factory, const grpc_channel_args* args,
+    grpc_handshake_manager* handshake_mgr) {
   grpc_handshake_manager_add(handshake_mgr,
                              grpc_http_connect_handshaker_create());
 }
 
-static void handshaker_factory_destroy(grpc_exec_ctx* exec_ctx,
-                                       grpc_handshaker_factory* factory) {}
+static void handshaker_factory_destroy(grpc_handshaker_factory* factory) {}
 
 static const grpc_handshaker_factory_vtable handshaker_factory_vtable = {
     handshaker_factory_add_handshakers, handshaker_factory_destroy};