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.

2 files changed, 42 insertions, 44 deletions

diff --git a/test/core/slice/b64_test.c b/test/core/slice/b64_test.c
index bd375aa6a7..0740315195 100644
--- a/test/core/slice/b64_test.c
+++ b/test/core/slice/b64_test.c
@@ -44,14 +44,14 @@ static void test_simple_encode_decode_b64(int url_safe, int multiline) {
   const char *hello = "hello";
   char *hello_b64 =
       grpc_base64_encode(hello, strlen(hello), url_safe, multiline);
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_slice hello_slice = grpc_base64_decode(&exec_ctx, hello_b64, url_safe);
+  exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_slice hello_slice = grpc_base64_decode(hello_b64, url_safe);
   GPR_ASSERT(GRPC_SLICE_LENGTH(hello_slice) == strlen(hello));
   GPR_ASSERT(strncmp((const char *)GRPC_SLICE_START_PTR(hello_slice), hello,
                      GRPC_SLICE_LENGTH(hello_slice)) == 0);
 
-  grpc_slice_unref_internal(&exec_ctx, hello_slice);
-  grpc_exec_ctx_finish(&exec_ctx);
+  grpc_slice_unref_internal(hello_slice);
+  grpc_exec_ctx_finish();
   gpr_free(hello_b64);
 }
 
@@ -64,15 +64,15 @@ static void test_full_range_encode_decode_b64(int url_safe, int multiline) {
 
   /* Try all the different paddings. */
   for (i = 0; i < 3; i++) {
-    grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+    exec_ctx = GRPC_EXEC_CTX_INIT;
     b64 = grpc_base64_encode(orig, sizeof(orig) - i, url_safe, multiline);
-    orig_decoded = grpc_base64_decode(&exec_ctx, b64, url_safe);
+    orig_decoded = grpc_base64_decode(b64, url_safe);
     GPR_ASSERT(GRPC_SLICE_LENGTH(orig_decoded) == (sizeof(orig) - i));
     GPR_ASSERT(buffers_are_equal(orig, GRPC_SLICE_START_PTR(orig_decoded),
                                  sizeof(orig) - i));
-    grpc_slice_unref_internal(&exec_ctx, orig_decoded);
+    grpc_slice_unref_internal(orig_decoded);
     gpr_free(b64);
-    grpc_exec_ctx_finish(&exec_ctx);
+    grpc_exec_ctx_finish();
   }
 }
 
@@ -116,19 +116,19 @@ static void test_url_safe_unsafe_mismatch_failure(void) {
   int url_safe = 1;
   for (i = 0; i < sizeof(orig); i++) orig[i] = (uint8_t)i;
 
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  exec_ctx = GRPC_EXEC_CTX_INIT;
   b64 = grpc_base64_encode(orig, sizeof(orig), url_safe, 0);
-  orig_decoded = grpc_base64_decode(&exec_ctx, b64, !url_safe);
+  orig_decoded = grpc_base64_decode(b64, !url_safe);
   GPR_ASSERT(GRPC_SLICE_IS_EMPTY(orig_decoded));
   gpr_free(b64);
-  grpc_slice_unref_internal(&exec_ctx, orig_decoded);
+  grpc_slice_unref_internal(orig_decoded);
 
   b64 = grpc_base64_encode(orig, sizeof(orig), !url_safe, 0);
-  orig_decoded = grpc_base64_decode(&exec_ctx, b64, url_safe);
+  orig_decoded = grpc_base64_decode(b64, url_safe);
   GPR_ASSERT(GRPC_SLICE_IS_EMPTY(orig_decoded));
   gpr_free(b64);
-  grpc_slice_unref_internal(&exec_ctx, orig_decoded);
-  grpc_exec_ctx_finish(&exec_ctx);
+  grpc_slice_unref_internal(orig_decoded);
+  grpc_exec_ctx_finish();
 }
 
 static void test_rfc4648_test_vectors(void) {
@@ -166,40 +166,40 @@ static void test_rfc4648_test_vectors(void) {
 static void test_unpadded_decode(void) {
   grpc_slice decoded;
 
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  decoded = grpc_base64_decode(&exec_ctx, "Zm9vYmFy", 0);
+  exec_ctx = GRPC_EXEC_CTX_INIT;
+  decoded = grpc_base64_decode("Zm9vYmFy", 0);
   GPR_ASSERT(!GRPC_SLICE_IS_EMPTY(decoded));
   GPR_ASSERT(grpc_slice_str_cmp(decoded, "foobar") == 0);
   grpc_slice_unref(decoded);
 
-  decoded = grpc_base64_decode(&exec_ctx, "Zm9vYmE", 0);
+  decoded = grpc_base64_decode("Zm9vYmE", 0);
   GPR_ASSERT(!GRPC_SLICE_IS_EMPTY(decoded));
   GPR_ASSERT(grpc_slice_str_cmp(decoded, "fooba") == 0);
   grpc_slice_unref(decoded);
 
-  decoded = grpc_base64_decode(&exec_ctx, "Zm9vYg", 0);
+  decoded = grpc_base64_decode("Zm9vYg", 0);
   GPR_ASSERT(!GRPC_SLICE_IS_EMPTY(decoded));
   GPR_ASSERT(grpc_slice_str_cmp(decoded, "foob") == 0);
   grpc_slice_unref(decoded);
 
-  decoded = grpc_base64_decode(&exec_ctx, "Zm9v", 0);
+  decoded = grpc_base64_decode("Zm9v", 0);
   GPR_ASSERT(!GRPC_SLICE_IS_EMPTY(decoded));
   GPR_ASSERT(grpc_slice_str_cmp(decoded, "foo") == 0);
   grpc_slice_unref(decoded);
 
-  decoded = grpc_base64_decode(&exec_ctx, "Zm8", 0);
+  decoded = grpc_base64_decode("Zm8", 0);
   GPR_ASSERT(!GRPC_SLICE_IS_EMPTY(decoded));
   GPR_ASSERT(grpc_slice_str_cmp(decoded, "fo") == 0);
   grpc_slice_unref(decoded);
 
-  decoded = grpc_base64_decode(&exec_ctx, "Zg", 0);
+  decoded = grpc_base64_decode("Zg", 0);
   GPR_ASSERT(!GRPC_SLICE_IS_EMPTY(decoded));
   GPR_ASSERT(grpc_slice_str_cmp(decoded, "f") == 0);
   grpc_slice_unref(decoded);
 
-  decoded = grpc_base64_decode(&exec_ctx, "", 0);
+  decoded = grpc_base64_decode("", 0);
   GPR_ASSERT(GRPC_SLICE_IS_EMPTY(decoded));
-  grpc_exec_ctx_finish(&exec_ctx);
+  grpc_exec_ctx_finish();
 }
 
 int main(int argc, char **argv) {
diff --git a/test/core/slice/slice_hash_table_test.c b/test/core/slice/slice_hash_table_test.c
index f3689aac64..67748433b1 100644
--- a/test/core/slice/slice_hash_table_test.c
+++ b/test/core/slice/slice_hash_table_test.c
@@ -58,9 +58,7 @@ static void check_non_existent_value(const char* key_string,
   grpc_slice_unref(key);
 }
 
-static void destroy_string(grpc_exec_ctx* exec_ctx, void* value) {
-  gpr_free(value);
-}
+static void destroy_string(void* value) { gpr_free(value); }
 
 static grpc_slice_hash_table* create_table_from_entries(
     const test_entry* test_entries, size_t num_test_entries,
@@ -119,9 +117,9 @@ static void test_slice_hash_table() {
   check_values(test_entries, num_entries, table);
   check_non_existent_value("XX", table);
   // Clean up.
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_slice_hash_table_unref(&exec_ctx, table);
-  grpc_exec_ctx_finish(&exec_ctx);
+  exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_slice_hash_table_unref(table);
+  grpc_exec_ctx_finish();
 }
 
 static int value_cmp_fn(void* a, void* b) {
@@ -147,10 +145,10 @@ static void test_slice_hash_table_eq() {
       create_table_from_entries(test_entries_b, num_entries_b, value_cmp_fn);
 
   GPR_ASSERT(grpc_slice_hash_table_cmp(table_a, table_b) == 0);
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_slice_hash_table_unref(&exec_ctx, table_a);
-  grpc_slice_hash_table_unref(&exec_ctx, table_b);
-  grpc_exec_ctx_finish(&exec_ctx);
+  exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_slice_hash_table_unref(table_a);
+  grpc_slice_hash_table_unref(table_b);
+  grpc_exec_ctx_finish();
 }
 
 static void test_slice_hash_table_not_eq() {
@@ -219,17 +217,17 @@ static void test_slice_hash_table_not_eq() {
       create_table_from_entries(test_entries_h, num_entries_h, pointer_cmp_fn);
   GPR_ASSERT(grpc_slice_hash_table_cmp(table_g, table_h) != 0);
 
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_slice_hash_table_unref(&exec_ctx, table_a);
-  grpc_slice_hash_table_unref(&exec_ctx, table_b_larger);
-  grpc_slice_hash_table_unref(&exec_ctx, table_b_smaller);
-  grpc_slice_hash_table_unref(&exec_ctx, table_c);
-  grpc_slice_hash_table_unref(&exec_ctx, table_d);
-  grpc_slice_hash_table_unref(&exec_ctx, table_e);
-  grpc_slice_hash_table_unref(&exec_ctx, table_f);
-  grpc_slice_hash_table_unref(&exec_ctx, table_g);
-  grpc_slice_hash_table_unref(&exec_ctx, table_h);
-  grpc_exec_ctx_finish(&exec_ctx);
+  exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_slice_hash_table_unref(table_a);
+  grpc_slice_hash_table_unref(table_b_larger);
+  grpc_slice_hash_table_unref(table_b_smaller);
+  grpc_slice_hash_table_unref(table_c);
+  grpc_slice_hash_table_unref(table_d);
+  grpc_slice_hash_table_unref(table_e);
+  grpc_slice_hash_table_unref(table_f);
+  grpc_slice_hash_table_unref(table_g);
+  grpc_slice_hash_table_unref(table_h);
+  grpc_exec_ctx_finish();
 }
 
 int main(int argc, char** argv) {