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, 7 insertions, 8 deletions

diff --git a/src/core/lib/surface/channel_ping.cc b/src/core/lib/surface/channel_ping.cc
index f45b568958..5d41b8e9e4 100644
--- a/src/core/lib/surface/channel_ping.cc
+++ b/src/core/lib/surface/channel_ping.cc
@@ -33,15 +33,14 @@ typedef struct {
   grpc_cq_completion completion_storage;
 } ping_result;
 
-static void ping_destroy(grpc_exec_ctx *exec_ctx, void *arg,
-                         grpc_cq_completion *storage) {
+static void ping_destroy(void *arg, grpc_cq_completion *storage) {
   gpr_free(arg);
 }
 
-static void ping_done(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
+static void ping_done(void *arg, grpc_error *error) {
   ping_result *pr = (ping_result *)arg;
-  grpc_cq_end_op(exec_ctx, pr->cq, pr->tag, GRPC_ERROR_REF(error), ping_destroy,
-                 pr, &pr->completion_storage);
+  grpc_cq_end_op(pr->cq, pr->tag, GRPC_ERROR_REF(error), ping_destroy, pr,
+                 &pr->completion_storage);
 }
 
 void grpc_channel_ping(grpc_channel *channel, grpc_completion_queue *cq,
@@ -52,7 +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);
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  ExecCtx _local_exec_ctx;
   GPR_ASSERT(reserved == NULL);
   pr->tag = tag;
   pr->cq = cq;
@@ -60,6 +59,6 @@ void grpc_channel_ping(grpc_channel *channel, grpc_completion_queue *cq,
   op->send_ping = &pr->closure;
   op->bind_pollset = grpc_cq_pollset(cq);
   GPR_ASSERT(grpc_cq_begin_op(cq, tag));
-  top_elem->filter->start_transport_op(&exec_ctx, top_elem, op);
-  grpc_exec_ctx_finish(&exec_ctx);
+  top_elem->filter->start_transport_op(top_elem, op);
+  grpc_exec_ctx_finish();
 }