Progress towards making grpc_slice_unref_internal take an exec_ctx
diff --git a/src/core/ext/client_channel/http_connect_handshaker.c b/src/core/ext/client_channel/http_connect_handshaker.c
index 8204289..6ce1953 100644
--- a/src/core/ext/client_channel/http_connect_handshaker.c
+++ b/src/core/ext/client_channel/http_connect_handshaker.c
@@ -76,7 +76,7 @@
   if (gpr_unref(&handshaker->refcount)) {
     gpr_free(handshaker->proxy_server);
     gpr_free(handshaker->server_name);
-    grpc_slice_buffer_destroy(&handshaker->write_buffer);
+    grpc_slice_buffer_destroy_internal(exec_ctx, &handshaker->write_buffer);
     grpc_http_parser_destroy(&handshaker->http_parser);
     grpc_http_response_destroy(&handshaker->http_response);
     gpr_free(handshaker);
@@ -142,7 +142,7 @@
                                &handshaker->read_buffer->slices[i + 1],
                                handshaker->read_buffer->count - i - 1);
         grpc_slice_buffer_swap(handshaker->read_buffer, &tmp_buffer);
-        grpc_slice_buffer_destroy(&tmp_buffer);
+        grpc_slice_buffer_destroy_internal(exec_ctx, &tmp_buffer);
         break;
       }
     }
@@ -159,7 +159,7 @@
   // 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(handshaker->read_buffer);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx, handshaker->read_buffer);
     grpc_endpoint_read(exec_ctx, handshaker->endpoint, handshaker->read_buffer,
                        &handshaker->response_read_closure);
     return;
diff --git a/src/core/ext/client_channel/resolver_factory.h b/src/core/ext/client_channel/resolver_factory.h
index 4da42e8..76b1f45 100644
--- a/src/core/ext/client_channel/resolver_factory.h
+++ b/src/core/ext/client_channel/resolver_factory.h
@@ -55,7 +55,8 @@
   void (*unref)(grpc_resolver_factory *factory);
 
   /** Implementation of grpc_resolver_factory_create_resolver */
-  grpc_resolver *(*create_resolver)(grpc_resolver_factory *factory,
+  grpc_resolver *(*create_resolver)(grpc_exec_ctx *exec_ctx,
+                                    grpc_resolver_factory *factory,
                                     grpc_resolver_args *args);
 
   /** Implementation of grpc_resolver_factory_get_default_authority */
@@ -70,7 +71,8 @@
 
 /** Create a resolver instance for a name */
 grpc_resolver *grpc_resolver_factory_create_resolver(
-    grpc_resolver_factory *factory, grpc_resolver_args *args);
+    grpc_exec_ctx *exec_ctx, grpc_resolver_factory *factory,
+    grpc_resolver_args *args);
 
 /** Return a (freshly allocated with gpr_malloc) string representing
     the default authority to use for this scheme. */
diff --git a/src/core/ext/client_channel/subchannel.c b/src/core/ext/client_channel/subchannel.c
index a5d7c0d..2175d20 100644
--- a/src/core/ext/client_channel/subchannel.c
+++ b/src/core/ext/client_channel/subchannel.c
@@ -46,6 +46,7 @@
 #include "src/core/lib/channel/connected_channel.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/support/backoff.h"
 #include "src/core/lib/surface/channel.h"
 #include "src/core/lib/surface/channel_init.h"
@@ -206,7 +207,7 @@
   gpr_free((void *)c->filters);
   grpc_channel_args_destroy(c->args);
   gpr_free(c->addr);
-  grpc_slice_unref(c->initial_connect_string);
+  grpc_slice_unref_internal(exec_ctx, c->initial_connect_string);
   grpc_connectivity_state_destroy(exec_ctx, &c->state_tracker);
   grpc_connector_unref(exec_ctx, c->connector);
   grpc_pollset_set_destroy(c->pollset_set);
diff --git a/src/core/ext/client_channel/uri_parser.c b/src/core/ext/client_channel/uri_parser.c
index 0fbc542..bcb6a1d 100644
--- a/src/core/ext/client_channel/uri_parser.c
+++ b/src/core/ext/client_channel/uri_parser.c
@@ -35,14 +35,13 @@
 
 #include <string.h>
 
-#include <grpc/slice.h>
-#include <grpc/slice_buffer.h>
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include <grpc/support/port_platform.h>
+#include <grpc/support/slice.h>
+#include <grpc/support/slice_buffer.h>
 #include <grpc/support/string_util.h>
 
-#include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 
 /** a size_t default value... maps to all 1's */
@@ -149,38 +148,38 @@
     uri->num_query_parts = 0;
     return;
   }
-  grpc_slice query_slice =
-      grpc_slice_new(uri->query, strlen(uri->query), do_nothing);
-  grpc_slice_buffer query_parts; /* the &-separated elements of the query */
-  grpc_slice_buffer query_param_parts; /* the =-separated subelements */
+  gpr_slice query_slice =
+      gpr_slice_new(uri->query, strlen(uri->query), do_nothing);
+  gpr_slice_buffer query_parts; /* the &-separated elements of the query */
+  gpr_slice_buffer query_param_parts; /* the =-separated subelements */
 
-  grpc_slice_buffer_init(&query_parts);
-  grpc_slice_buffer_init(&query_param_parts);
+  gpr_slice_buffer_init(&query_parts);
+  gpr_slice_buffer_init(&query_param_parts);
 
-  grpc_slice_split(query_slice, QUERY_PARTS_SEPARATOR, &query_parts);
+  gpr_slice_split(query_slice, QUERY_PARTS_SEPARATOR, &query_parts);
   uri->query_parts = gpr_malloc(query_parts.count * sizeof(char *));
   uri->query_parts_values = gpr_malloc(query_parts.count * sizeof(char *));
   uri->num_query_parts = query_parts.count;
   for (size_t i = 0; i < query_parts.count; i++) {
-    grpc_slice_split(query_parts.slices[i], QUERY_PARTS_VALUE_SEPARATOR,
-                     &query_param_parts);
+    gpr_slice_split(query_parts.slices[i], QUERY_PARTS_VALUE_SEPARATOR,
+                    &query_param_parts);
     GPR_ASSERT(query_param_parts.count > 0);
     uri->query_parts[i] =
-        grpc_dump_slice(query_param_parts.slices[0], GPR_DUMP_ASCII);
+        gpr_dump_slice(query_param_parts.slices[0], GPR_DUMP_ASCII);
     if (query_param_parts.count > 1) {
       /* TODO(dgq): only the first value after the separator is considered.
        * Perhaps all chars after the first separator for the query part should
        * be included, even if they include the separator. */
       uri->query_parts_values[i] =
-          grpc_dump_slice(query_param_parts.slices[1], GPR_DUMP_ASCII);
+          gpr_dump_slice(query_param_parts.slices[1], GPR_DUMP_ASCII);
     } else {
       uri->query_parts_values[i] = NULL;
     }
-    grpc_slice_buffer_reset_and_unref(&query_param_parts);
+    gpr_slice_buffer_reset_and_unref(&query_param_parts);
   }
-  grpc_slice_buffer_destroy(&query_parts);
-  grpc_slice_buffer_destroy(&query_param_parts);
-  grpc_slice_unref(query_slice);
+  gpr_slice_buffer_destroy(&query_parts);
+  gpr_slice_buffer_destroy(&query_param_parts);
+  gpr_slice_unref(query_slice);
 }
 
 grpc_uri *grpc_uri_parse(const char *uri_text, int suppress_errors) {
diff --git a/src/core/ext/lb_policy/grpclb/grpclb.c b/src/core/ext/lb_policy/grpclb/grpclb.c
index 2ae96c5..00c7468 100644
--- a/src/core/ext/lb_policy/grpclb/grpclb.c
+++ b/src/core/ext/lb_policy/grpclb/grpclb.c
@@ -121,6 +121,7 @@
 #include "src/core/ext/lb_policy/grpclb/load_balancer_api.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/surface/call.h"
@@ -970,7 +971,8 @@
 static void srv_status_rcvd_cb(grpc_exec_ctx *exec_ctx, void *arg,
                                grpc_error *error);
 
-static lb_client_data *lb_client_data_create(glb_lb_policy *glb_policy) {
+static lb_client_data *lb_client_data_create(grpc_exec_ctx *exec_ctx,
+                                             glb_lb_policy *glb_policy) {
   GPR_ASSERT(glb_policy->server_name != NULL);
   GPR_ASSERT(glb_policy->server_name[0] != '\0');
 
@@ -1004,7 +1006,7 @@
   grpc_slice request_payload_slice = grpc_grpclb_request_encode(request);
   lb_client->request_payload =
       grpc_raw_byte_buffer_create(&request_payload_slice, 1);
-  grpc_slice_unref(request_payload_slice);
+  grpc_slice_unref_internal(exec_ctx, request_payload_slice);
   grpc_grpclb_request_destroy(request);
 
   lb_client->status_details = NULL;
@@ -1035,7 +1037,7 @@
                                glb_lb_policy *glb_policy) {
   GPR_ASSERT(glb_policy->lb_channel != NULL);
 
-  glb_policy->lb_client = lb_client_data_create(glb_policy);
+  glb_policy->lb_client = lb_client_data_create(exec_ctx, glb_policy);
   grpc_call_error call_error;
   grpc_op ops[1];
   memset(ops, 0, sizeof(ops));
@@ -1126,7 +1128,7 @@
     grpc_grpclb_serverlist *serverlist =
         grpc_grpclb_response_parse_serverlist(response_slice);
     if (serverlist != NULL) {
-      grpc_slice_unref(response_slice);
+      grpc_slice_unref_internal(exec_ctx, response_slice);
       if (grpc_lb_glb_trace) {
         gpr_log(GPR_INFO, "Serverlist with %lu servers received",
                 (unsigned long)serverlist->num_servers);
@@ -1185,7 +1187,7 @@
     GPR_ASSERT(serverlist == NULL);
     gpr_log(GPR_ERROR, "Invalid LB response received: '%s'",
             grpc_dump_slice(response_slice, GPR_DUMP_ASCII));
-    grpc_slice_unref(response_slice);
+    grpc_slice_unref_internal(exec_ctx, response_slice);
 
     /* Disconnect from server returning invalid response. */
     op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
diff --git a/src/core/ext/resolver/sockaddr/sockaddr_resolver.c b/src/core/ext/resolver/sockaddr/sockaddr_resolver.c
index 26a650a..a3f13cd 100644
--- a/src/core/ext/resolver/sockaddr/sockaddr_resolver.c
+++ b/src/core/ext/resolver/sockaddr/sockaddr_resolver.c
@@ -47,6 +47,7 @@
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/resolve_address.h"
 #include "src/core/lib/iomgr/unix_sockets_posix.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 
@@ -161,7 +162,8 @@
 
 static void do_nothing(void *ignored) {}
 
-static grpc_resolver *sockaddr_create(grpc_resolver_args *args,
+static grpc_resolver *sockaddr_create(grpc_exec_ctx *exec_ctx,
+                                      grpc_resolver_args *args,
                                       int parse(grpc_uri *uri,
                                                 grpc_resolved_address *dst)) {
   if (0 != strcmp(args->uri->authority, "")) {
@@ -188,8 +190,8 @@
     gpr_free(part_str);
     if (errors_found) break;
   }
-  grpc_slice_buffer_destroy(&path_parts);
-  grpc_slice_unref(path_slice);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &path_parts);
+  grpc_slice_unref_internal(exec_ctx, path_slice);
   if (errors_found) {
     grpc_lb_addresses_destroy(addresses);
     return NULL;
@@ -219,8 +221,9 @@
 
 #define DECL_FACTORY(name)                                                  \
   static grpc_resolver *name##_factory_create_resolver(                     \
-      grpc_resolver_factory *factory, grpc_resolver_args *args) {           \
-    return sockaddr_create(args, parse_##name);                             \
+      grpc_exec_ctx *exec_ctx, grpc_resolver_factory *factory,              \
+      grpc_resolver_args *args) {                                           \
+    return sockaddr_create(exec_ctx, args, parse_##name);                   \
   }                                                                         \
   static const grpc_resolver_factory_vtable name##_factory_vtable = {       \
       sockaddr_factory_ref, sockaddr_factory_unref,                         \
diff --git a/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c b/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c
index aa2ecf5..f46e849 100644
--- a/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c
+++ b/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c
@@ -62,7 +62,7 @@
   grpc_endpoint *server_endpoint =
       grpc_tcp_create(grpc_fd_create(fd, name), resource_quota,
                       GRPC_TCP_DEFAULT_READ_SLICE_SIZE, name);
-  grpc_resource_quota_internal_unref(&exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(&exec_ctx, resource_quota);
 
   gpr_free(name);
 
diff --git a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
index 942638a..15ef778 100644
--- a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
+++ b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
@@ -98,7 +98,7 @@
         grpc_server_setup_transport(
             exec_ctx, connection_state->server_state->server, transport,
             connection_state->accepting_pollset, args_copy);
-        grpc_channel_args_destroy(args_copy);
+        grpc_channel_args_destroy(exec_ctx, args_copy);
         grpc_chttp2_transport_start_reading(exec_ctx, transport, NULL);
       } else {
         /* We need to consume this here, because the server may already have
@@ -110,7 +110,7 @@
   } else {
     gpr_log(GPR_ERROR, "Secure transport failed with error %d", status);
   }
-  grpc_channel_args_destroy(connection_state->args);
+  grpc_channel_args_destroy(exec_ctx, connection_state->args);
   grpc_tcp_server_unref(exec_ctx, connection_state->server_state->tcp);
   gpr_free(connection_state);
 }
@@ -125,7 +125,7 @@
     gpr_log(GPR_ERROR, "Handshaking failed: %s", error_str);
     grpc_error_free_string(error_str);
     GRPC_ERROR_UNREF(error);
-    grpc_channel_args_destroy(args);
+    grpc_channel_args_destroy(exec_ctx, args);
     gpr_free(read_buffer);
     grpc_handshake_manager_shutdown(exec_ctx, connection_state->handshake_mgr);
     grpc_handshake_manager_destroy(exec_ctx, connection_state->handshake_mgr);
diff --git a/src/core/ext/transport/chttp2/transport/bin_decoder.c b/src/core/ext/transport/chttp2/transport/bin_decoder.c
index 3eef80b..8db36e4 100644
--- a/src/core/ext/transport/chttp2/transport/bin_decoder.c
+++ b/src/core/ext/transport/chttp2/transport/bin_decoder.c
@@ -34,6 +34,7 @@
 #include "src/core/ext/transport/chttp2/transport/bin_decoder.h"
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 
@@ -143,7 +144,8 @@
   return true;
 }
 
-grpc_slice grpc_chttp2_base64_decode(grpc_slice input) {
+grpc_slice grpc_chttp2_base64_decode(grpc_exec_ctx *exec_ctx,
+                                     grpc_slice input) {
   size_t input_length = GRPC_SLICE_LENGTH(input);
   size_t output_length = input_length / 4 * 3;
   struct grpc_base64_decode_context ctx;
@@ -179,7 +181,7 @@
     char *s = grpc_dump_slice(input, GPR_DUMP_ASCII);
     gpr_log(GPR_ERROR, "Base64 decoding failed, input string:\n%s\n", s);
     gpr_free(s);
-    grpc_slice_unref(output);
+    grpc_slice_unref_internal(exec_ctx, output);
     return gpr_empty_slice();
   }
   GPR_ASSERT(ctx.output_cur == GRPC_SLICE_END_PTR(output));
@@ -187,7 +189,8 @@
   return output;
 }
 
-grpc_slice grpc_chttp2_base64_decode_with_length(grpc_slice input,
+grpc_slice grpc_chttp2_base64_decode_with_length(grpc_exec_ctx *exec_ctx,
+                                                 grpc_slice input,
                                                  size_t output_length) {
   size_t input_length = GRPC_SLICE_LENGTH(input);
   grpc_slice output = grpc_slice_malloc(output_length);
@@ -200,7 +203,7 @@
             "grpc_chttp2_base64_decode_with_length has a length of %d, which "
             "has a tail of 1 byte.\n",
             (int)input_length);
-    grpc_slice_unref(output);
+    grpc_slice_unref_internal(exec_ctx, output);
     return gpr_empty_slice();
   }
 
@@ -210,7 +213,7 @@
             "than the max possible output length %d.\n",
             (int)output_length,
             (int)(input_length / 4 * 3 + tail_xtra[input_length % 4]));
-    grpc_slice_unref(output);
+    grpc_slice_unref_internal(exec_ctx, output);
     return gpr_empty_slice();
   }
 
@@ -224,7 +227,7 @@
     char *s = grpc_dump_slice(input, GPR_DUMP_ASCII);
     gpr_log(GPR_ERROR, "Base64 decoding failed, input string:\n%s\n", s);
     gpr_free(s);
-    grpc_slice_unref(output);
+    grpc_slice_unref_internal(exec_ctx, output);
     return gpr_empty_slice();
   }
   GPR_ASSERT(ctx.output_cur == GRPC_SLICE_END_PTR(output));
diff --git a/src/core/ext/transport/chttp2/transport/bin_decoder.h b/src/core/ext/transport/chttp2/transport/bin_decoder.h
index 83a90be..48ffb2a 100644
--- a/src/core/ext/transport/chttp2/transport/bin_decoder.h
+++ b/src/core/ext/transport/chttp2/transport/bin_decoder.h
@@ -55,12 +55,13 @@
 
 /* base64 decode a slice with pad chars. Returns a new slice, does not take
    ownership of the input. Returns an empty slice if decoding is failed. */
-grpc_slice grpc_chttp2_base64_decode(grpc_slice input);
+grpc_slice grpc_chttp2_base64_decode(grpc_exec_ctx *exec_ctx, grpc_slice input);
 
 /* base64 decode a slice without pad chars, data length is needed. Returns a new
    slice, does not take ownership of the input. Returns an empty slice if
    decoding is failed. */
-grpc_slice grpc_chttp2_base64_decode_with_length(grpc_slice input,
+grpc_slice grpc_chttp2_base64_decode_with_length(grpc_exec_ctx *exec_ctx,
+                                                 grpc_slice input,
                                                  size_t output_length);
 
 #endif /* GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_BIN_DECODER_H */
diff --git a/src/core/ext/transport/chttp2/transport/bin_encoder.h b/src/core/ext/transport/chttp2/transport/bin_encoder.h
index 9e143b4..477559d 100644
--- a/src/core/ext/transport/chttp2/transport/bin_encoder.h
+++ b/src/core/ext/transport/chttp2/transport/bin_encoder.h
@@ -47,7 +47,7 @@
 /* equivalent to:
    grpc_slice x = grpc_chttp2_base64_encode(input);
    grpc_slice y = grpc_chttp2_huffman_compress(x);
-   grpc_slice_unref(x);
+   grpc_slice_unref_internal(exec_ctx, x);
    return y; */
 grpc_slice grpc_chttp2_base64_encode_and_huffman_compress_impl(
     grpc_slice input);
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.c b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
index 1ffa916..0c61159 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.c
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
@@ -51,6 +51,7 @@
 #include "src/core/lib/http/parser.h"
 #include "src/core/lib/iomgr/workqueue.h"
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/transport/static_metadata.h"
@@ -144,12 +145,12 @@
 
   grpc_endpoint_destroy(exec_ctx, t->ep);
 
-  grpc_slice_buffer_destroy(&t->qbuf);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &t->qbuf);
 
-  grpc_slice_buffer_destroy(&t->outbuf);
-  grpc_chttp2_hpack_compressor_destroy(&t->hpack_compressor);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &t->outbuf);
+  grpc_chttp2_hpack_compressor_destroy(exec_ctx, &t->hpack_compressor);
 
-  grpc_slice_buffer_destroy(&t->read_buffer);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &t->read_buffer);
   grpc_chttp2_hpack_parser_destroy(&t->hpack_parser);
   grpc_chttp2_goaway_parser_destroy(&t->goaway_parser);
 
@@ -532,7 +533,7 @@
   grpc_chttp2_data_parser_destroy(exec_ctx, &s->data_parser);
   grpc_chttp2_incoming_metadata_buffer_destroy(&s->metadata_buffer[0]);
   grpc_chttp2_incoming_metadata_buffer_destroy(&s->metadata_buffer[1]);
-  grpc_slice_buffer_destroy(&s->flow_controlled_buffer);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &s->flow_controlled_buffer);
   GRPC_ERROR_UNREF(s->read_closed_error);
   GRPC_ERROR_UNREF(s->write_closed_error);
 
@@ -761,7 +762,7 @@
   char *msg = grpc_dump_slice(goaway_text, GPR_DUMP_HEX | GPR_DUMP_ASCII);
   GRPC_CHTTP2_IF_TRACING(
       gpr_log(GPR_DEBUG, "got goaway [%d]: %s", goaway_error, msg));
-  grpc_slice_unref(goaway_text);
+  grpc_slice_unref_internal(exec_ctx, goaway_text);
   t->seen_goaway = 1;
   /* lie: use transient failure from the transport to indicate goaway has been
    * received */
@@ -1244,7 +1245,7 @@
   if (op->send_goaway) {
     send_goaway(exec_ctx, t,
                 grpc_chttp2_grpc_status_to_http2_error(op->goaway_status),
-                grpc_slice_ref(*op->goaway_message));
+                grpc_slice_ref_internal(*op->goaway_message));
   }
 
   if (op->set_accept_stream) {
@@ -1474,21 +1475,22 @@
     char status_string[GPR_LTOA_MIN_BUFSIZE];
     gpr_ltoa(status, status_string);
     grpc_chttp2_incoming_metadata_buffer_add(
-        &s->metadata_buffer[1],
-        grpc_mdelem_from_metadata_strings(
-            GRPC_MDSTR_GRPC_STATUS, grpc_mdstr_from_string(status_string)));
+        &s->metadata_buffer[1], grpc_mdelem_from_metadata_strings(
+                                    exec_ctx, GRPC_MDSTR_GRPC_STATUS,
+                                    grpc_mdstr_from_string(status_string)));
     if (slice) {
       grpc_chttp2_incoming_metadata_buffer_add(
           &s->metadata_buffer[1],
           grpc_mdelem_from_metadata_strings(
-              GRPC_MDSTR_GRPC_MESSAGE,
-              grpc_mdstr_from_slice(grpc_slice_ref(*slice))));
+              exec_ctx, GRPC_MDSTR_GRPC_MESSAGE,
+              grpc_mdstr_from_slice(exec_ctx,
+                                    grpc_slice_ref_internal(*slice))));
     }
     s->published_metadata[1] = GRPC_METADATA_SYNTHESIZED_FROM_FAKE;
     grpc_chttp2_maybe_complete_recv_trailing_metadata(exec_ctx, t, s);
   }
   if (slice) {
-    grpc_slice_unref(*slice);
+    grpc_slice_unref_internal(exec_ctx, *slice);
   }
 }
 
@@ -1862,7 +1864,7 @@
     keep_reading = true;
     GRPC_CHTTP2_REF_TRANSPORT(t, "keep_reading");
   }
-  grpc_slice_buffer_reset_and_unref(&t->read_buffer);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &t->read_buffer);
 
   if (keep_reading) {
     grpc_endpoint_read(exec_ctx, t->ep, &t->read_buffer, &t->read_action_begin);
@@ -1916,7 +1918,7 @@
                                        grpc_chttp2_incoming_byte_stream *bs) {
   if (gpr_unref(&bs->refs)) {
     GRPC_ERROR_UNREF(bs->error);
-    grpc_slice_buffer_destroy(&bs->slices);
+    grpc_slice_buffer_destroy_internal(exec_ctx, &bs->slices);
     gpr_mu_destroy(&bs->slice_mu);
     gpr_free(bs);
   }
diff --git a/src/core/ext/transport/chttp2/transport/hpack_encoder.c b/src/core/ext/transport/chttp2/transport/hpack_encoder.c
index eb68fe3..49a8326 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_encoder.c
+++ b/src/core/ext/transport/chttp2/transport/hpack_encoder.c
@@ -48,6 +48,7 @@
 #include "src/core/ext/transport/chttp2/transport/bin_encoder.h"
 #include "src/core/ext/transport/chttp2/transport/hpack_table.h"
 #include "src/core/ext/transport/chttp2/transport/varint.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/transport/metadata.h"
 #include "src/core/lib/transport/static_metadata.h"
 #include "src/core/lib/transport/timeout_encoding.h"
@@ -183,7 +184,8 @@
 }
 
 /* add an element to the decoder table */
-static void add_elem(grpc_chttp2_hpack_compressor *c, grpc_mdelem *elem) {
+static void add_elem(grpc_exec_ctx *exec_ctx, grpc_chttp2_hpack_compressor *c,
+                     grpc_mdelem *elem) {
   uint32_t key_hash = elem->key->hash;
   uint32_t elem_hash = GRPC_MDSTR_KV_HASH(key_hash, elem->value->hash);
   uint32_t new_index = c->tail_remote_index + c->table_elems + 1;
@@ -227,12 +229,12 @@
   } else if (c->indices_elems[HASH_FRAGMENT_2(elem_hash)] <
              c->indices_elems[HASH_FRAGMENT_3(elem_hash)]) {
     /* not there: replace oldest */
-    GRPC_MDELEM_UNREF(c->entries_elems[HASH_FRAGMENT_2(elem_hash)]);
+    GRPC_MDELEM_UNREF(exec_ctx, c->entries_elems[HASH_FRAGMENT_2(elem_hash)]);
     c->entries_elems[HASH_FRAGMENT_2(elem_hash)] = GRPC_MDELEM_REF(elem);
     c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index;
   } else {
     /* not there: replace oldest */
-    GRPC_MDELEM_UNREF(c->entries_elems[HASH_FRAGMENT_3(elem_hash)]);
+    GRPC_MDELEM_UNREF(exec_ctx, c->entries_elems[HASH_FRAGMENT_3(elem_hash)]);
     c->entries_elems[HASH_FRAGMENT_3(elem_hash)] = GRPC_MDELEM_REF(elem);
     c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index;
   }
@@ -251,11 +253,11 @@
     c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index;
   } else if (c->indices_keys[HASH_FRAGMENT_2(key_hash)] <
              c->indices_keys[HASH_FRAGMENT_3(key_hash)]) {
-    GRPC_MDSTR_UNREF(c->entries_keys[HASH_FRAGMENT_2(key_hash)]);
+    GRPC_MDSTR_UNREF(exec_ctx, c->entries_keys[HASH_FRAGMENT_2(key_hash)]);
     c->entries_keys[HASH_FRAGMENT_2(key_hash)] = GRPC_MDSTR_REF(elem->key);
     c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index;
   } else {
-    GRPC_MDSTR_UNREF(c->entries_keys[HASH_FRAGMENT_3(key_hash)]);
+    GRPC_MDSTR_UNREF(exec_ctx, c->entries_keys[HASH_FRAGMENT_3(key_hash)]);
     c->entries_keys[HASH_FRAGMENT_3(key_hash)] = GRPC_MDSTR_REF(elem->key);
     c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index;
   }
@@ -294,7 +296,7 @@
                            add_tiny_header_data(st, len_pfx), len_pfx);
   GRPC_CHTTP2_WRITE_VARINT((uint32_t)len_val, 1, huffman_prefix,
                            add_tiny_header_data(st, len_val_len), len_val_len);
-  add_header_data(st, grpc_slice_ref(value_slice));
+  add_header_data(st, grpc_slice_ref_internal(value_slice));
 }
 
 static void emit_lithdr_noidx(grpc_chttp2_hpack_compressor *c,
@@ -311,7 +313,7 @@
                            add_tiny_header_data(st, len_pfx), len_pfx);
   GRPC_CHTTP2_WRITE_VARINT((uint32_t)len_val, 1, huffman_prefix,
                            add_tiny_header_data(st, len_val_len), len_val_len);
-  add_header_data(st, grpc_slice_ref(value_slice));
+  add_header_data(st, grpc_slice_ref_internal(value_slice));
 }
 
 static void emit_lithdr_incidx_v(grpc_chttp2_hpack_compressor *c,
@@ -327,10 +329,10 @@
   *add_tiny_header_data(st, 1) = 0x40;
   GRPC_CHTTP2_WRITE_VARINT(len_key, 1, 0x00,
                            add_tiny_header_data(st, len_key_len), len_key_len);
-  add_header_data(st, grpc_slice_ref(elem->key->slice));
+  add_header_data(st, grpc_slice_ref_internal(elem->key->slice));
   GRPC_CHTTP2_WRITE_VARINT(len_val, 1, huffman_prefix,
                            add_tiny_header_data(st, len_val_len), len_val_len);
-  add_header_data(st, grpc_slice_ref(value_slice));
+  add_header_data(st, grpc_slice_ref_internal(value_slice));
 }
 
 static void emit_lithdr_noidx_v(grpc_chttp2_hpack_compressor *c,
@@ -346,10 +348,10 @@
   *add_tiny_header_data(st, 1) = 0x00;
   GRPC_CHTTP2_WRITE_VARINT(len_key, 1, 0x00,
                            add_tiny_header_data(st, len_key_len), len_key_len);
-  add_header_data(st, grpc_slice_ref(elem->key->slice));
+  add_header_data(st, grpc_slice_ref_internal(elem->key->slice));
   GRPC_CHTTP2_WRITE_VARINT(len_val, 1, huffman_prefix,
                            add_tiny_header_data(st, len_val_len), len_val_len);
-  add_header_data(st, grpc_slice_ref(value_slice));
+  add_header_data(st, grpc_slice_ref_internal(value_slice));
 }
 
 static void emit_advertise_table_size_change(grpc_chttp2_hpack_compressor *c,
@@ -366,8 +368,8 @@
 }
 
 /* encode an mdelem */
-static void hpack_enc(grpc_chttp2_hpack_compressor *c, grpc_mdelem *elem,
-                      framer_state *st) {
+static void hpack_enc(grpc_exec_ctx *exec_ctx, grpc_chttp2_hpack_compressor *c,
+                      grpc_mdelem *elem, framer_state *st) {
   uint32_t key_hash = elem->key->hash;
   uint32_t elem_hash = GRPC_MDSTR_KV_HASH(key_hash, elem->value->hash);
   size_t decoder_space_usage;
@@ -417,7 +419,7 @@
     /* HIT: key (first cuckoo hash) */
     if (should_add_elem) {
       emit_lithdr_incidx(c, dynidx(c, indices_key), elem, st);
-      add_elem(c, elem);
+      add_elem(exec_ctx, c, elem);
       return;
     } else {
       emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st);
@@ -432,7 +434,7 @@
     /* HIT: key (first cuckoo hash) */
     if (should_add_elem) {
       emit_lithdr_incidx(c, dynidx(c, indices_key), elem, st);
-      add_elem(c, elem);
+      add_elem(exec_ctx, c, elem);
       return;
     } else {
       emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st);
@@ -445,7 +447,7 @@
 
   if (should_add_elem) {
     emit_lithdr_incidx_v(c, elem, st);
-    add_elem(c, elem);
+    add_elem(exec_ctx, c, elem);
     return;
   } else {
     emit_lithdr_noidx_v(c, elem, st);
@@ -457,16 +459,17 @@
 #define STRLEN_LIT(x) (sizeof(x) - 1)
 #define TIMEOUT_KEY "grpc-timeout"
 
-static void deadline_enc(grpc_chttp2_hpack_compressor *c, gpr_timespec deadline,
+static void deadline_enc(grpc_exec_ctx *exec_ctx,
+                         grpc_chttp2_hpack_compressor *c, gpr_timespec deadline,
                          framer_state *st) {
   char timeout_str[GRPC_HTTP2_TIMEOUT_ENCODE_MIN_BUFSIZE];
   grpc_mdelem *mdelem;
   grpc_http2_encode_timeout(
       gpr_time_sub(deadline, gpr_now(deadline.clock_type)), timeout_str);
   mdelem = grpc_mdelem_from_metadata_strings(
-      GRPC_MDSTR_GRPC_TIMEOUT, grpc_mdstr_from_string(timeout_str));
-  hpack_enc(c, mdelem, st);
-  GRPC_MDELEM_UNREF(mdelem);
+      exec_ctx, GRPC_MDSTR_GRPC_TIMEOUT, grpc_mdstr_from_string(timeout_str));
+  hpack_enc(exec_ctx, c, mdelem, st);
+  GRPC_MDELEM_UNREF(exec_ctx, mdelem);
 }
 
 static uint32_t elems_for_bytes(uint32_t bytes) { return (bytes + 31) / 32; }
@@ -483,11 +486,12 @@
          sizeof(*c->table_elem_size) * c->cap_table_elems);
 }
 
-void grpc_chttp2_hpack_compressor_destroy(grpc_chttp2_hpack_compressor *c) {
+void grpc_chttp2_hpack_compressor_destroy(grpc_exec_ctx *exec_ctx,
+                                          grpc_chttp2_hpack_compressor *c) {
   int i;
   for (i = 0; i < GRPC_CHTTP2_HPACKC_NUM_VALUES; i++) {
-    if (c->entries_keys[i]) GRPC_MDSTR_UNREF(c->entries_keys[i]);
-    if (c->entries_elems[i]) GRPC_MDELEM_UNREF(c->entries_elems[i]);
+    if (c->entries_keys[i]) GRPC_MDSTR_UNREF(exec_ctx, c->entries_keys[i]);
+    if (c->entries_elems[i]) GRPC_MDELEM_UNREF(exec_ctx, c->entries_elems[i]);
   }
   gpr_free(c->table_elem_size);
 }
@@ -542,7 +546,8 @@
   }
 }
 
-void grpc_chttp2_encode_header(grpc_chttp2_hpack_compressor *c,
+void grpc_chttp2_encode_header(grpc_exec_ctx *exec_ctx,
+                               grpc_chttp2_hpack_compressor *c,
                                uint32_t stream_id,
                                grpc_metadata_batch *metadata, int is_eof,
                                size_t max_frame_size,
@@ -571,11 +576,11 @@
   }
   grpc_metadata_batch_assert_ok(metadata);
   for (l = metadata->list.head; l; l = l->next) {
-    hpack_enc(c, l->md, &st);
+    hpack_enc(exec_ctx, c, l->md, &st);
   }
   deadline = metadata->deadline;
   if (gpr_time_cmp(deadline, gpr_inf_future(deadline.clock_type)) != 0) {
-    deadline_enc(c, deadline, &st);
+    deadline_enc(exec_ctx, c, deadline, &st);
   }
 
   finish_frame(&st, 1, is_eof);
diff --git a/src/core/ext/transport/chttp2/transport/hpack_encoder.h b/src/core/ext/transport/chttp2/transport/hpack_encoder.h
index bcbd675..3a35496 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_encoder.h
+++ b/src/core/ext/transport/chttp2/transport/hpack_encoder.h
@@ -83,13 +83,15 @@
 } grpc_chttp2_hpack_compressor;
 
 void grpc_chttp2_hpack_compressor_init(grpc_chttp2_hpack_compressor *c);
-void grpc_chttp2_hpack_compressor_destroy(grpc_chttp2_hpack_compressor *c);
+void grpc_chttp2_hpack_compressor_destroy(grpc_exec_ctx *exec_ctx,
+                                          grpc_chttp2_hpack_compressor *c);
 void grpc_chttp2_hpack_compressor_set_max_table_size(
     grpc_chttp2_hpack_compressor *c, uint32_t max_table_size);
 void grpc_chttp2_hpack_compressor_set_max_usable_size(
     grpc_chttp2_hpack_compressor *c, uint32_t max_table_size);
 
-void grpc_chttp2_encode_header(grpc_chttp2_hpack_compressor *c, uint32_t id,
+void grpc_chttp2_encode_header(grpc_exec_ctx *exec_ctx,
+                               grpc_chttp2_hpack_compressor *c, uint32_t id,
                                grpc_metadata_batch *metadata, int is_eof,
                                size_t max_frame_size,
                                grpc_transport_one_way_stats *stats,
diff --git a/src/core/ext/transport/chttp2/transport/hpack_parser.c b/src/core/ext/transport/chttp2/transport/hpack_parser.c
index 1046c31..e805aac 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_parser.c
+++ b/src/core/ext/transport/chttp2/transport/hpack_parser.c
@@ -669,11 +669,11 @@
 static grpc_error *on_hdr(grpc_exec_ctx *exec_ctx, grpc_chttp2_hpack_parser *p,
                           grpc_mdelem *md, int add_to_table) {
   if (add_to_table) {
-    grpc_error *err = grpc_chttp2_hptbl_add(&p->table, md);
+    grpc_error *err = grpc_chttp2_hptbl_add(exec_ctx, &p->table, md);
     if (err != GRPC_ERROR_NONE) return err;
   }
   if (p->on_header == NULL) {
-    GRPC_MDELEM_UNREF(md);
+    GRPC_MDELEM_UNREF(exec_ctx, md);
     return GRPC_ERROR_CREATE("on_header callback not set");
   }
   p->on_header(exec_ctx, p->on_header_user_data, md);
@@ -814,10 +814,10 @@
                                         const uint8_t *end) {
   grpc_mdelem *md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
   GPR_ASSERT(md != NULL); /* handled in string parsing */
-  grpc_error *err = on_hdr(
-      exec_ctx, p, grpc_mdelem_from_metadata_strings(GRPC_MDSTR_REF(md->key),
-                                                     take_string(p, &p->value)),
-      1);
+  grpc_error *err = on_hdr(exec_ctx, p, grpc_mdelem_from_metadata_strings(
+                                            exec_ctx, GRPC_MDSTR_REF(md->key),
+                                            take_string(p, &p->value)),
+                           1);
   if (err != GRPC_ERROR_NONE) return parse_error(exec_ctx, p, cur, end, err);
   return parse_begin(exec_ctx, p, cur, end);
 }
@@ -827,10 +827,10 @@
                                           grpc_chttp2_hpack_parser *p,
                                           const uint8_t *cur,
                                           const uint8_t *end) {
-  grpc_error *err = on_hdr(
-      exec_ctx, p, grpc_mdelem_from_metadata_strings(take_string(p, &p->key),
-                                                     take_string(p, &p->value)),
-      1);
+  grpc_error *err = on_hdr(exec_ctx, p, grpc_mdelem_from_metadata_strings(
+                                            exec_ctx, take_string(p, &p->key),
+                                            take_string(p, &p->value)),
+                           1);
   if (err != GRPC_ERROR_NONE) return parse_error(exec_ctx, p, cur, end, err);
   return parse_begin(exec_ctx, p, cur, end);
 }
@@ -882,10 +882,10 @@
                                         const uint8_t *end) {
   grpc_mdelem *md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
   GPR_ASSERT(md != NULL); /* handled in string parsing */
-  grpc_error *err = on_hdr(
-      exec_ctx, p, grpc_mdelem_from_metadata_strings(GRPC_MDSTR_REF(md->key),
-                                                     take_string(p, &p->value)),
-      0);
+  grpc_error *err = on_hdr(exec_ctx, p, grpc_mdelem_from_metadata_strings(
+                                            exec_ctx, GRPC_MDSTR_REF(md->key),
+                                            take_string(p, &p->value)),
+                           0);
   if (err != GRPC_ERROR_NONE) return parse_error(exec_ctx, p, cur, end, err);
   return parse_begin(exec_ctx, p, cur, end);
 }
@@ -895,10 +895,10 @@
                                           grpc_chttp2_hpack_parser *p,
                                           const uint8_t *cur,
                                           const uint8_t *end) {
-  grpc_error *err = on_hdr(
-      exec_ctx, p, grpc_mdelem_from_metadata_strings(take_string(p, &p->key),
-                                                     take_string(p, &p->value)),
-      0);
+  grpc_error *err = on_hdr(exec_ctx, p, grpc_mdelem_from_metadata_strings(
+                                            exec_ctx, take_string(p, &p->key),
+                                            take_string(p, &p->value)),
+                           0);
   if (err != GRPC_ERROR_NONE) return parse_error(exec_ctx, p, cur, end, err);
   return parse_begin(exec_ctx, p, cur, end);
 }
@@ -950,10 +950,10 @@
                                         const uint8_t *end) {
   grpc_mdelem *md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
   GPR_ASSERT(md != NULL); /* handled in string parsing */
-  grpc_error *err = on_hdr(
-      exec_ctx, p, grpc_mdelem_from_metadata_strings(GRPC_MDSTR_REF(md->key),
-                                                     take_string(p, &p->value)),
-      0);
+  grpc_error *err = on_hdr(exec_ctx, p, grpc_mdelem_from_metadata_strings(
+                                            exec_ctx, GRPC_MDSTR_REF(md->key),
+                                            take_string(p, &p->value)),
+                           0);
   if (err != GRPC_ERROR_NONE) return parse_error(exec_ctx, p, cur, end, err);
   return parse_begin(exec_ctx, p, cur, end);
 }
@@ -963,10 +963,10 @@
                                           grpc_chttp2_hpack_parser *p,
                                           const uint8_t *cur,
                                           const uint8_t *end) {
-  grpc_error *err = on_hdr(
-      exec_ctx, p, grpc_mdelem_from_metadata_strings(take_string(p, &p->key),
-                                                     take_string(p, &p->value)),
-      0);
+  grpc_error *err = on_hdr(exec_ctx, p, grpc_mdelem_from_metadata_strings(
+                                            exec_ctx, take_string(p, &p->key),
+                                            take_string(p, &p->value)),
+                           0);
   if (err != GRPC_ERROR_NONE) return parse_error(exec_ctx, p, cur, end, err);
   return parse_begin(exec_ctx, p, cur, end);
 }
@@ -1019,7 +1019,7 @@
     gpr_log(GPR_INFO, "MAX TABLE SIZE: %d", p->index);
   }
   grpc_error *err =
-      grpc_chttp2_hptbl_set_current_table_size(&p->table, p->index);
+      grpc_chttp2_hptbl_set_current_table_size(exec_ctx, &p->table, p->index);
   if (err != GRPC_ERROR_NONE) return parse_error(exec_ctx, p, cur, end, err);
   return parse_begin(exec_ctx, p, cur, end);
 }
@@ -1545,7 +1545,7 @@
   p->value.length = 0;
   p->dynamic_table_update_allowed = 2;
   p->last_error = GRPC_ERROR_NONE;
-  grpc_chttp2_hptbl_init(&p->table);
+  grpc_chttp2_hptbl_init(exec_ctx, &p->table);
 }
 
 void grpc_chttp2_hpack_parser_set_has_priority(grpc_chttp2_hpack_parser *p) {
@@ -1554,7 +1554,7 @@
 }
 
 void grpc_chttp2_hpack_parser_destroy(grpc_chttp2_hpack_parser *p) {
-  grpc_chttp2_hptbl_destroy(&p->table);
+  grpc_chttp2_hptbl_destroy(exec_ctx, &p->table);
   GRPC_ERROR_UNREF(p->last_error);
   gpr_free(p->key.str);
   gpr_free(p->value.str);
diff --git a/src/core/ext/transport/chttp2/transport/hpack_table.c b/src/core/ext/transport/chttp2/transport/hpack_table.c
index 2dc793d..26d4036 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_table.c
+++ b/src/core/ext/transport/chttp2/transport/hpack_table.c
@@ -179,7 +179,7 @@
          GRPC_CHTTP2_HPACK_ENTRY_OVERHEAD;
 }
 
-void grpc_chttp2_hptbl_init(grpc_chttp2_hptbl *tbl) {
+void grpc_chttp2_hptbl_init(grpc_exec_ctx *exec_ctx, grpc_chttp2_hptbl *tbl) {
   size_t i;
 
   memset(tbl, 0, sizeof(*tbl));
@@ -190,18 +190,20 @@
   tbl->ents = gpr_malloc(sizeof(*tbl->ents) * tbl->cap_entries);
   memset(tbl->ents, 0, sizeof(*tbl->ents) * tbl->cap_entries);
   for (i = 1; i <= GRPC_CHTTP2_LAST_STATIC_ENTRY; i++) {
-    tbl->static_ents[i - 1] =
-        grpc_mdelem_from_strings(static_table[i].key, static_table[i].value);
+    tbl->static_ents[i - 1] = grpc_mdelem_from_strings(
+        exec_ctx, static_table[i].key, static_table[i].value);
   }
 }
 
-void grpc_chttp2_hptbl_destroy(grpc_chttp2_hptbl *tbl) {
+void grpc_chttp2_hptbl_destroy(grpc_exec_ctx *exec_ctx,
+                               grpc_chttp2_hptbl *tbl) {
   size_t i;
   for (i = 0; i < GRPC_CHTTP2_LAST_STATIC_ENTRY; i++) {
-    GRPC_MDELEM_UNREF(tbl->static_ents[i]);
+    GRPC_MDELEM_UNREF(exec_ctx, tbl->static_ents[i]);
   }
   for (i = 0; i < tbl->num_ents; i++) {
-    GRPC_MDELEM_UNREF(tbl->ents[(tbl->first_ent + i) % tbl->cap_entries]);
+    GRPC_MDELEM_UNREF(exec_ctx,
+                      tbl->ents[(tbl->first_ent + i) % tbl->cap_entries]);
   }
   gpr_free(tbl->ents);
 }
@@ -224,7 +226,7 @@
 }
 
 /* Evict one element from the table */
-static void evict1(grpc_chttp2_hptbl *tbl) {
+static void evict1(grpc_exec_ctx *exec_ctx, grpc_chttp2_hptbl *tbl) {
   grpc_mdelem *first_ent = tbl->ents[tbl->first_ent];
   size_t elem_bytes = GRPC_SLICE_LENGTH(first_ent->key->slice) +
                       GRPC_SLICE_LENGTH(first_ent->value->slice) +
@@ -233,7 +235,7 @@
   tbl->mem_used -= (uint32_t)elem_bytes;
   tbl->first_ent = ((tbl->first_ent + 1) % tbl->cap_entries);
   tbl->num_ents--;
-  GRPC_MDELEM_UNREF(first_ent);
+  GRPC_MDELEM_UNREF(exec_ctx, first_ent);
 }
 
 static void rebuild_ents(grpc_chttp2_hptbl *tbl, uint32_t new_cap) {
@@ -249,7 +251,8 @@
   tbl->first_ent = 0;
 }
 
-void grpc_chttp2_hptbl_set_max_bytes(grpc_chttp2_hptbl *tbl,
+void grpc_chttp2_hptbl_set_max_bytes(grpc_exec_ctx *exec_ctx,
+                                     grpc_chttp2_hptbl *tbl,
                                      uint32_t max_bytes) {
   if (tbl->max_bytes == max_bytes) {
     return;
@@ -258,12 +261,13 @@
     gpr_log(GPR_DEBUG, "Update hpack parser max size to %d", max_bytes);
   }
   while (tbl->mem_used > max_bytes) {
-    evict1(tbl);
+    evict1(exec_ctx, tbl);
   }
   tbl->max_bytes = max_bytes;
 }
 
-grpc_error *grpc_chttp2_hptbl_set_current_table_size(grpc_chttp2_hptbl *tbl,
+grpc_error *grpc_chttp2_hptbl_set_current_table_size(grpc_exec_ctx *exec_ctx,
+                                                     grpc_chttp2_hptbl *tbl,
                                                      uint32_t bytes) {
   if (tbl->current_table_bytes == bytes) {
     return GRPC_ERROR_NONE;
@@ -281,7 +285,7 @@
     gpr_log(GPR_DEBUG, "Update hpack parser table size to %d", bytes);
   }
   while (tbl->mem_used > bytes) {
-    evict1(tbl);
+    evict1(exec_ctx, tbl);
   }
   tbl->current_table_bytes = bytes;
   tbl->max_entries = entries_for_bytes(bytes);
@@ -296,7 +300,8 @@
   return GRPC_ERROR_NONE;
 }
 
-grpc_error *grpc_chttp2_hptbl_add(grpc_chttp2_hptbl *tbl, grpc_mdelem *md) {
+grpc_error *grpc_chttp2_hptbl_add(grpc_exec_ctx *exec_ctx,
+                                  grpc_chttp2_hptbl *tbl, grpc_mdelem *md) {
   /* determine how many bytes of buffer this entry represents */
   size_t elem_bytes = GRPC_SLICE_LENGTH(md->key->slice) +
                       GRPC_SLICE_LENGTH(md->value->slice) +
@@ -326,14 +331,14 @@
      * empty table.
      */
     while (tbl->num_ents) {
-      evict1(tbl);
+      evict1(exec_ctx, tbl);
     }
     return GRPC_ERROR_NONE;
   }
 
   /* evict entries to ensure no overflow */
   while (elem_bytes > (size_t)tbl->current_table_bytes - tbl->mem_used) {
-    evict1(tbl);
+    evict1(exec_ctx, tbl);
   }
 
   /* copy the finalized entry in */
diff --git a/src/core/ext/transport/chttp2/transport/hpack_table.h b/src/core/ext/transport/chttp2/transport/hpack_table.h
index 2ca130e..144574e 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_table.h
+++ b/src/core/ext/transport/chttp2/transport/hpack_table.h
@@ -84,18 +84,21 @@
 } grpc_chttp2_hptbl;
 
 /* initialize a hpack table */
-void grpc_chttp2_hptbl_init(grpc_chttp2_hptbl *tbl);
-void grpc_chttp2_hptbl_destroy(grpc_chttp2_hptbl *tbl);
-void grpc_chttp2_hptbl_set_max_bytes(grpc_chttp2_hptbl *tbl,
+void grpc_chttp2_hptbl_init(grpc_exec_ctx *exec_ctx, grpc_chttp2_hptbl *tbl);
+void grpc_chttp2_hptbl_destroy(grpc_exec_ctx *exec_ctx, grpc_chttp2_hptbl *tbl);
+void grpc_chttp2_hptbl_set_max_bytes(grpc_exec_ctx *exec_ctx,
+                                     grpc_chttp2_hptbl *tbl,
                                      uint32_t max_bytes);
-grpc_error *grpc_chttp2_hptbl_set_current_table_size(grpc_chttp2_hptbl *tbl,
+grpc_error *grpc_chttp2_hptbl_set_current_table_size(grpc_exec_ctx *exec_ctx,
+                                                     grpc_chttp2_hptbl *tbl,
                                                      uint32_t bytes);
 
 /* lookup a table entry based on its hpack index */
 grpc_mdelem *grpc_chttp2_hptbl_lookup(const grpc_chttp2_hptbl *tbl,
                                       uint32_t index);
 /* add a table entry to the index */
-grpc_error *grpc_chttp2_hptbl_add(grpc_chttp2_hptbl *tbl,
+grpc_error *grpc_chttp2_hptbl_add(grpc_exec_ctx *exec_ctx,
+                                  grpc_chttp2_hptbl *tbl,
                                   grpc_mdelem *md) GRPC_MUST_USE_RESULT;
 /* Find a key/value pair in the table... returns the index in the table of the
    most similar entry, or 0 if the value was not found */
diff --git a/src/core/ext/transport/chttp2/transport/writing.c b/src/core/ext/transport/chttp2/transport/writing.c
index 139e738..d7f45b1 100644
--- a/src/core/ext/transport/chttp2/transport/writing.c
+++ b/src/core/ext/transport/chttp2/transport/writing.c
@@ -39,6 +39,7 @@
 
 #include "src/core/ext/transport/chttp2/transport/http2_errors.h"
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/slice/slice_internal.h"
 
 static void add_to_write_list(grpc_chttp2_write_cb **list,
                               grpc_chttp2_write_cb *cb) {
@@ -254,7 +255,7 @@
     }
     GRPC_CHTTP2_STREAM_UNREF(exec_ctx, s, "chttp2_writing:end");
   }
-  grpc_slice_buffer_reset_and_unref(&t->outbuf);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &t->outbuf);
   GRPC_ERROR_UNREF(error);
   GPR_TIMER_END("grpc_chttp2_end_write", 0);
 }
diff --git a/src/core/lib/channel/channel_args.c b/src/core/lib/channel/channel_args.c
index cfc072c..c956b0f 100644
--- a/src/core/lib/channel/channel_args.c
+++ b/src/core/lib/channel/channel_args.c
@@ -184,7 +184,7 @@
   return b;
 }
 
-void grpc_channel_args_destroy(grpc_channel_args *a) {
+void grpc_channel_args_destroy(grpc_exec_ctx *exec_ctx, grpc_channel_args *a) {
   size_t i;
   if (!a) return;
   for (i = 0; i < a->num_args; i++) {
@@ -195,7 +195,8 @@
       case GRPC_ARG_INTEGER:
         break;
       case GRPC_ARG_POINTER:
-        a->args[i].value.pointer.vtable->destroy(a->args[i].value.pointer.p);
+        a->args[i].value.pointer.vtable->destroy(exec_ctx,
+                                                 a->args[i].value.pointer.p);
         break;
     }
     gpr_free(a->args[i].key);
@@ -249,7 +250,8 @@
 }
 
 grpc_channel_args *grpc_channel_args_compression_algorithm_set_state(
-    grpc_channel_args **a, grpc_compression_algorithm algorithm, int state) {
+    grpc_exec_ctx *exec_ctx, grpc_channel_args **a,
+    grpc_compression_algorithm algorithm, int state) {
   int *states_arg = NULL;
   grpc_channel_args *result = *a;
   const int states_arg_found =
@@ -282,7 +284,7 @@
       GPR_BITCLEAR((unsigned *)&tmp.value.integer, algorithm);
     }
     result = grpc_channel_args_copy_and_add(*a, &tmp, 1);
-    grpc_channel_args_destroy(*a);
+    grpc_channel_args_destroy(exec_ctx, *a);
     *a = result;
   }
   return result;
diff --git a/src/core/lib/channel/channel_args.h b/src/core/lib/channel/channel_args.h
index 1e05303..5933133 100644
--- a/src/core/lib/channel/channel_args.h
+++ b/src/core/lib/channel/channel_args.h
@@ -67,7 +67,7 @@
                                            const grpc_channel_args *b);
 
 /** Destroy arguments created by \a grpc_channel_args_copy */
-void grpc_channel_args_destroy(grpc_channel_args *a);
+void grpc_channel_args_destroy(grpc_exec_ctx *exec_ctx, grpc_channel_args *a);
 
 /** Returns the compression algorithm set in \a a. */
 grpc_compression_algorithm grpc_channel_args_get_compression_algorithm(
@@ -87,7 +87,8 @@
  * modified to point to the returned instance (which may be different from the
  * input value of \a a). */
 grpc_channel_args *grpc_channel_args_compression_algorithm_set_state(
-    grpc_channel_args **a, grpc_compression_algorithm algorithm, int enabled);
+    grpc_exec_ctx *exec_ctx, grpc_channel_args **a,
+    grpc_compression_algorithm algorithm, int enabled);
 
 /** Returns the bitset representing the support state (true for enabled, false
  * for disabled) for compression algorithms.
diff --git a/src/core/lib/channel/channel_stack.c b/src/core/lib/channel/channel_stack.c
index 9da8195..c32e7e6 100644
--- a/src/core/lib/channel/channel_stack.c
+++ b/src/core/lib/channel/channel_stack.c
@@ -292,7 +292,7 @@
   grpc_transport_stream_op *op = gpr_malloc(sizeof(*op));
   memset(op, 0, sizeof(*op));
   op->on_complete = grpc_closure_create(destroy_op, op);
-  grpc_transport_stream_op_add_cancellation_with_message(op, status,
+  grpc_transport_stream_op_add_cancellation_with_message(exec_ctx, op, status,
                                                          optional_message);
   elem->filter->start_transport_stream_op(exec_ctx, elem, op);
 }
@@ -304,6 +304,6 @@
   grpc_transport_stream_op *op = gpr_malloc(sizeof(*op));
   memset(op, 0, sizeof(*op));
   op->on_complete = grpc_closure_create(destroy_op, op);
-  grpc_transport_stream_op_add_close(op, status, optional_message);
+  grpc_transport_stream_op_add_close(exec_ctx, op, status, optional_message);
   elem->filter->start_transport_stream_op(exec_ctx, elem, op);
 }
diff --git a/src/core/lib/channel/channel_stack_builder.c b/src/core/lib/channel/channel_stack_builder.c
index eda4968..366bd0d 100644
--- a/src/core/lib/channel/channel_stack_builder.c
+++ b/src/core/lib/channel/channel_stack_builder.c
@@ -138,9 +138,10 @@
 }
 
 void grpc_channel_stack_builder_set_channel_arguments(
-    grpc_channel_stack_builder *builder, const grpc_channel_args *args) {
+    grpc_exec_ctx *exec_ctx, grpc_channel_stack_builder *builder,
+    const grpc_channel_args *args) {
   if (builder->args != NULL) {
-    grpc_channel_args_destroy(builder->args);
+    grpc_channel_args_destroy(exec_ctx, builder->args);
   }
   builder->args = grpc_channel_args_copy(args);
 }
@@ -213,7 +214,8 @@
   return true;
 }
 
-void grpc_channel_stack_builder_destroy(grpc_channel_stack_builder *builder) {
+void grpc_channel_stack_builder_destroy(grpc_exec_ctx *exec_ctx,
+                                        grpc_channel_stack_builder *builder) {
   filter_node *p = builder->begin.next;
   while (p != &builder->end) {
     filter_node *next = p->next;
@@ -221,7 +223,7 @@
     p = next;
   }
   if (builder->args != NULL) {
-    grpc_channel_args_destroy(builder->args);
+    grpc_channel_args_destroy(exec_ctx, builder->args);
   }
   gpr_free(builder->target);
   gpr_free(builder);
@@ -270,7 +272,7 @@
     i++;
   }
 
-  grpc_channel_stack_builder_destroy(builder);
+  grpc_channel_stack_builder_destroy(exec_ctx, builder);
   gpr_free((grpc_channel_filter **)filters);
 
   return result;
diff --git a/src/core/lib/channel/channel_stack_builder.h b/src/core/lib/channel/channel_stack_builder.h
index 4a00f7b..3532819 100644
--- a/src/core/lib/channel/channel_stack_builder.h
+++ b/src/core/lib/channel/channel_stack_builder.h
@@ -73,7 +73,8 @@
 
 /// Set channel arguments: copies args
 void grpc_channel_stack_builder_set_channel_arguments(
-    grpc_channel_stack_builder *builder, const grpc_channel_args *args);
+    grpc_exec_ctx *exec_ctx, grpc_channel_stack_builder *builder,
+    const grpc_channel_args *args);
 
 /// Return a borrowed pointer to the channel arguments
 const grpc_channel_args *grpc_channel_stack_builder_get_channel_arguments(
@@ -158,7 +159,8 @@
                                         void *destroy_arg);
 
 /// Destroy the builder without creating a channel stack
-void grpc_channel_stack_builder_destroy(grpc_channel_stack_builder *builder);
+void grpc_channel_stack_builder_destroy(grpc_exec_ctx *exec_ctx,
+                                        grpc_channel_stack_builder *builder);
 
 extern int grpc_trace_channel_stack_builder;
 
diff --git a/src/core/lib/channel/compress_filter.c b/src/core/lib/channel/compress_filter.c
index de71bcc..9cb5262 100644
--- a/src/core/lib/channel/compress_filter.c
+++ b/src/core/lib/channel/compress_filter.c
@@ -44,6 +44,7 @@
 #include "src/core/lib/compression/algorithm_metadata.h"
 #include "src/core/lib/compression/message_compress.h"
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/transport/static_metadata.h"
 
@@ -126,12 +127,14 @@
 
 /** Filter initial metadata */
 static void process_send_initial_metadata(
-    grpc_call_element *elem, grpc_metadata_batch *initial_metadata) {
+    grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+    grpc_metadata_batch *initial_metadata) {
   call_data *calld = elem->call_data;
   channel_data *channeld = elem->channel_data;
   /* Parse incoming request for compression. If any, it'll be available
    * at calld->compression_algorithm */
-  grpc_metadata_batch_filter(initial_metadata, compression_md_filter, elem);
+  grpc_metadata_batch_filter(exec_ctx, initial_metadata, compression_md_filter,
+                             elem);
   if (!calld->has_compression_algorithm) {
     /* If no algorithm was found in the metadata and we aren't
      * exceptionally skipping compression, fall back to the channel
@@ -157,7 +160,7 @@
 static void send_done(grpc_exec_ctx *exec_ctx, void *elemp, grpc_error *error) {
   grpc_call_element *elem = elemp;
   call_data *calld = elem->call_data;
-  grpc_slice_buffer_reset_and_unref(&calld->slices);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &calld->slices);
   calld->post_send->cb(exec_ctx, calld->post_send->cb_arg, error);
 }
 
@@ -167,8 +170,8 @@
   int did_compress;
   grpc_slice_buffer tmp;
   grpc_slice_buffer_init(&tmp);
-  did_compress =
-      grpc_msg_compress(calld->compression_algorithm, &calld->slices, &tmp);
+  did_compress = grpc_msg_compress(exec_ctx, calld->compression_algorithm,
+                                   &calld->slices, &tmp);
   if (did_compress) {
     if (grpc_compression_trace) {
       char *algo_name;
@@ -195,7 +198,7 @@
     }
   }
 
-  grpc_slice_buffer_destroy(&tmp);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &tmp);
 
   grpc_slice_buffer_stream_init(&calld->replacement_stream, &calld->slices,
                                 calld->send_flags);
@@ -239,7 +242,7 @@
   GPR_TIMER_BEGIN("compress_start_transport_stream_op", 0);
 
   if (op->send_initial_metadata) {
-    process_send_initial_metadata(elem, op->send_initial_metadata);
+    process_send_initial_metadata(exec_ctx, elem, op->send_initial_metadata);
   }
   if (op->send_message != NULL && !skip_compression(elem) &&
       0 == (op->send_message->flags & GRPC_WRITE_NO_COMPRESS)) {
@@ -277,7 +280,7 @@
                               void *ignored) {
   /* grab pointers to our data from the call element */
   call_data *calld = elem->call_data;
-  grpc_slice_buffer_destroy(&calld->slices);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &calld->slices);
 }
 
 /* Constructor for channel_data */
diff --git a/src/core/lib/channel/deadline_filter.c b/src/core/lib/channel/deadline_filter.c
index 449eb7b..3b24e52 100644
--- a/src/core/lib/channel/deadline_filter.c
+++ b/src/core/lib/channel/deadline_filter.c
@@ -41,6 +41,7 @@
 
 #include "src/core/lib/iomgr/exec_ctx.h"
 #include "src/core/lib/iomgr/timer.h"
+#include "src/core/lib/slice/slice_internal.h"
 
 //
 // grpc_deadline_state
@@ -58,7 +59,7 @@
     grpc_slice msg = grpc_slice_from_static_string("Deadline Exceeded");
     grpc_call_element_send_cancel_with_message(
         exec_ctx, elem, GRPC_STATUS_DEADLINE_EXCEEDED, &msg);
-    grpc_slice_unref(msg);
+    grpc_slice_unref_internal(exec_ctx, msg);
   }
   GRPC_CALL_STACK_UNREF(exec_ctx, deadline_state->call_stack, "deadline_timer");
 }
diff --git a/src/core/lib/channel/http_client_filter.c b/src/core/lib/channel/http_client_filter.c
index 0714f31..026e4d4 100644
--- a/src/core/lib/channel/http_client_filter.c
+++ b/src/core/lib/channel/http_client_filter.c
@@ -36,6 +36,7 @@
 #include <grpc/support/string_util.h>
 #include <string.h>
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/transport/static_metadata.h"
 #include "src/core/lib/transport/transport_impl.h"
@@ -136,8 +137,8 @@
   client_recv_filter_args a;
   a.elem = elem;
   a.exec_ctx = exec_ctx;
-  grpc_metadata_batch_filter(calld->recv_initial_metadata, client_recv_filter,
-                             &a);
+  grpc_metadata_batch_filter(exec_ctx, calld->recv_initial_metadata,
+                             client_recv_filter, &a);
   calld->on_done_recv->cb(exec_ctx, calld->on_done_recv->cb_arg, error);
 }
 
@@ -155,7 +156,7 @@
 static void send_done(grpc_exec_ctx *exec_ctx, void *elemp, grpc_error *error) {
   grpc_call_element *elem = elemp;
   call_data *calld = elem->call_data;
-  grpc_slice_buffer_reset_and_unref(&calld->slices);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &calld->slices);
   calld->post_send->cb(exec_ctx, calld->post_send->cb_arg, error);
 }
 
@@ -244,7 +245,7 @@
         /* when all the send_message data is available, then create a MDELEM and
         append to headers */
         grpc_mdelem *payload_bin = grpc_mdelem_from_metadata_strings(
-            GRPC_MDSTR_GRPC_PAYLOAD_BIN,
+            exec_ctx, GRPC_MDSTR_GRPC_PAYLOAD_BIN,
             grpc_mdstr_from_buffer(calld->payload_bytes,
                                    op->send_message->length));
         grpc_metadata_batch_add_tail(op->send_initial_metadata,
@@ -261,8 +262,8 @@
       }
     }
 
-    grpc_metadata_batch_filter(op->send_initial_metadata, client_strip_filter,
-                               elem);
+    grpc_metadata_batch_filter(exec_ctx, op->send_initial_metadata,
+                               client_strip_filter, elem);
     /* Send : prefixed headers, which have to be before any application
        layer headers. */
     grpc_metadata_batch_add_head(op->send_initial_metadata, &calld->method,
@@ -324,7 +325,7 @@
                               const grpc_call_final_info *final_info,
                               void *ignored) {
   call_data *calld = elem->call_data;
-  grpc_slice_buffer_destroy(&calld->slices);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &calld->slices);
 }
 
 static grpc_mdelem *scheme_from_args(const grpc_channel_args *args) {
@@ -425,7 +426,7 @@
   chand->max_payload_size_for_get =
       max_payload_size_from_args(args->channel_args);
   chand->user_agent = grpc_mdelem_from_metadata_strings(
-      GRPC_MDSTR_USER_AGENT,
+      exec_ctx, GRPC_MDSTR_USER_AGENT,
       user_agent_from_args(args->channel_args,
                            args->optional_transport->vtable->name));
 }
@@ -434,7 +435,7 @@
 static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
                                  grpc_channel_element *elem) {
   channel_data *chand = elem->channel_data;
-  GRPC_MDELEM_UNREF(chand->user_agent);
+  GRPC_MDELEM_UNREF(exec_ctx, chand->user_agent);
 }
 
 const grpc_channel_filter grpc_http_client_filter = {
diff --git a/src/core/lib/channel/http_server_filter.c b/src/core/lib/channel/http_server_filter.c
index 1063185..d09a2b1 100644
--- a/src/core/lib/channel/http_server_filter.c
+++ b/src/core/lib/channel/http_server_filter.c
@@ -37,6 +37,7 @@
 #include <grpc/support/log.h>
 #include <string.h>
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/transport/static_metadata.h"
 
 #define EXPECTED_CONTENT_TYPE "application/grpc"
@@ -155,7 +156,7 @@
     /* translate host to :authority since :authority may be
        omitted */
     grpc_mdelem *authority = grpc_mdelem_from_metadata_strings(
-        GRPC_MDSTR_AUTHORITY, GRPC_MDSTR_REF(md->value));
+        a->exec_ctx, GRPC_MDSTR_AUTHORITY, GRPC_MDSTR_REF(md->value));
     calld->seen_authority = 1;
     return authority;
   } else if (md->key == GRPC_MDSTR_GRPC_PAYLOAD_BIN) {
@@ -164,7 +165,7 @@
     calld->seen_payload_bin = 1;
     grpc_slice_buffer_init(&calld->read_slice_buffer);
     grpc_slice_buffer_add(&calld->read_slice_buffer,
-                          grpc_slice_ref(md->value->slice));
+                          grpc_slice_ref_internal(md->value->slice));
     grpc_slice_buffer_stream_init(&calld->read_stream,
                                   &calld->read_slice_buffer, 0);
     return NULL;
@@ -181,7 +182,8 @@
     server_filter_args a;
     a.elem = elem;
     a.exec_ctx = exec_ctx;
-    grpc_metadata_batch_filter(calld->recv_initial_metadata, server_filter, &a);
+    grpc_metadata_batch_filter(exec_ctx, calld->recv_initial_metadata,
+                               server_filter, &a);
     /* Have we seen the required http2 transport headers?
        (:method, :scheme, content-type, with :path and :authority covered
        at the channel level right now) */
diff --git a/src/core/lib/channel/message_size_filter.c b/src/core/lib/channel/message_size_filter.c
index 85c3077..50118b5 100644
--- a/src/core/lib/channel/message_size_filter.c
+++ b/src/core/lib/channel/message_size_filter.c
@@ -66,8 +66,10 @@
   return 0;
 }
 
+static void free_mem(grpc_exec_ctx* exec_ctx, void* p) { gpr_free(p); }
+
 static const grpc_mdstr_hash_table_vtable message_size_limits_vtable = {
-    gpr_free, message_size_limits_copy, message_size_limits_cmp};
+    free_mem, message_size_limits_copy, message_size_limits_cmp};
 
 static void* method_config_convert_value(
     const grpc_method_config* method_config) {
@@ -171,8 +173,8 @@
   calld->max_send_size = chand->max_send_size;
   calld->max_recv_size = chand->max_recv_size;
   if (chand->method_limit_table != NULL) {
-    message_size_limits* limits =
-        grpc_method_config_table_get(chand->method_limit_table, args->path);
+    message_size_limits* limits = grpc_method_config_table_get(
+        exec_ctx, chand->method_limit_table, args->path);
     if (limits != NULL) {
       if (limits->max_send_size >= 0 &&
           (limits->max_send_size < calld->max_send_size ||
@@ -225,7 +227,7 @@
   if (channel_arg != NULL) {
     GPR_ASSERT(channel_arg->type == GRPC_ARG_POINTER);
     chand->method_limit_table = grpc_method_config_table_convert(
-        (grpc_method_config_table*)channel_arg->value.pointer.p,
+        exec_ctx, (grpc_method_config_table*)channel_arg->value.pointer.p,
         method_config_convert_value, &message_size_limits_vtable);
   }
 }
@@ -234,7 +236,7 @@
 static void destroy_channel_elem(grpc_exec_ctx* exec_ctx,
                                  grpc_channel_element* elem) {
   channel_data* chand = elem->channel_data;
-  grpc_mdstr_hash_table_unref(chand->method_limit_table);
+  grpc_mdstr_hash_table_unref(exec_ctx, chand->method_limit_table);
 }
 
 const grpc_channel_filter grpc_message_size_filter = {
diff --git a/src/core/lib/compression/message_compress.c b/src/core/lib/compression/message_compress.c
index 6c245ac..49beb95 100644
--- a/src/core/lib/compression/message_compress.c
+++ b/src/core/lib/compression/message_compress.c
@@ -40,10 +40,12 @@
 
 #include <zlib.h>
 
+#include "src/core/lib/slice/slice_internal.h"
+
 #define OUTPUT_BLOCK_SIZE 1024
 
-static int zlib_body(z_stream* zs, grpc_slice_buffer* input,
-                     grpc_slice_buffer* output,
+static int zlib_body(grpc_exec_ctx* exec_ctx, z_stream* zs,
+                     grpc_slice_buffer* input, grpc_slice_buffer* output,
                      int (*flate)(z_stream* zs, int flush)) {
   int r;
   int flush;
@@ -87,7 +89,7 @@
   return 1;
 
 error:
-  grpc_slice_unref(outbuf);
+  grpc_slice_unref_internal(exec_ctx, outbuf);
   return 0;
 }
 
@@ -97,8 +99,8 @@
 
 static void zfree_gpr(void* opaque, void* address) { gpr_free(address); }
 
-static int zlib_compress(grpc_slice_buffer* input, grpc_slice_buffer* output,
-                         int gzip) {
+static int zlib_compress(grpc_exec_ctx* exec_ctx, grpc_slice_buffer* input,
+                         grpc_slice_buffer* output, int gzip) {
   z_stream zs;
   int r;
   size_t i;
@@ -110,10 +112,11 @@
   r = deflateInit2(&zs, Z_DEFAULT_COMPRESSION, Z_DEFLATED, 15 | (gzip ? 16 : 0),
                    8, Z_DEFAULT_STRATEGY);
   GPR_ASSERT(r == Z_OK);
-  r = zlib_body(&zs, input, output, deflate) && output->length < input->length;
+  r = zlib_body(exec_ctx, &zs, input, output, deflate) &&
+      output->length < input->length;
   if (!r) {
     for (i = count_before; i < output->count; i++) {
-      grpc_slice_unref(output->slices[i]);
+      grpc_slice_unref_internal(exec_ctx, output->slices[i]);
     }
     output->count = count_before;
     output->length = length_before;
@@ -122,8 +125,8 @@
   return r;
 }
 
-static int zlib_decompress(grpc_slice_buffer* input, grpc_slice_buffer* output,
-                           int gzip) {
+static int zlib_decompress(grpc_exec_ctx* exec_ctx, grpc_slice_buffer* input,
+                           grpc_slice_buffer* output, int gzip) {
   z_stream zs;
   int r;
   size_t i;
@@ -134,10 +137,10 @@
   zs.zfree = zfree_gpr;
   r = inflateInit2(&zs, 15 | (gzip ? 16 : 0));
   GPR_ASSERT(r == Z_OK);
-  r = zlib_body(&zs, input, output, inflate);
+  r = zlib_body(exec_ctx, &zs, input, output, inflate);
   if (!r) {
     for (i = count_before; i < output->count; i++) {
-      grpc_slice_unref(output->slices[i]);
+      grpc_slice_unref_internal(exec_ctx, output->slices[i]);
     }
     output->count = count_before;
     output->length = length_before;
@@ -149,12 +152,13 @@
 static int copy(grpc_slice_buffer* input, grpc_slice_buffer* output) {
   size_t i;
   for (i = 0; i < input->count; i++) {
-    grpc_slice_buffer_add(output, grpc_slice_ref(input->slices[i]));
+    grpc_slice_buffer_add(output, grpc_slice_ref_internal(input->slices[i]));
   }
   return 1;
 }
 
-static int compress_inner(grpc_compression_algorithm algorithm,
+static int compress_inner(grpc_exec_ctx* exec_ctx,
+                          grpc_compression_algorithm algorithm,
                           grpc_slice_buffer* input, grpc_slice_buffer* output) {
   switch (algorithm) {
     case GRPC_COMPRESS_NONE:
@@ -162,9 +166,9 @@
          rely on that here */
       return 0;
     case GRPC_COMPRESS_DEFLATE:
-      return zlib_compress(input, output, 0);
+      return zlib_compress(exec_ctx, input, output, 0);
     case GRPC_COMPRESS_GZIP:
-      return zlib_compress(input, output, 1);
+      return zlib_compress(exec_ctx, input, output, 1);
     case GRPC_COMPRESS_ALGORITHMS_COUNT:
       break;
   }
@@ -172,24 +176,26 @@
   return 0;
 }
 
-int grpc_msg_compress(grpc_compression_algorithm algorithm,
+int grpc_msg_compress(grpc_exec_ctx* exec_ctx,
+                      grpc_compression_algorithm algorithm,
                       grpc_slice_buffer* input, grpc_slice_buffer* output) {
-  if (!compress_inner(algorithm, input, output)) {
+  if (!compress_inner(exec_ctx, algorithm, input, output)) {
     copy(input, output);
     return 0;
   }
   return 1;
 }
 
-int grpc_msg_decompress(grpc_compression_algorithm algorithm,
+int grpc_msg_decompress(grpc_exec_ctx* exec_ctx,
+                        grpc_compression_algorithm algorithm,
                         grpc_slice_buffer* input, grpc_slice_buffer* output) {
   switch (algorithm) {
     case GRPC_COMPRESS_NONE:
       return copy(input, output);
     case GRPC_COMPRESS_DEFLATE:
-      return zlib_decompress(input, output, 0);
+      return zlib_decompress(exec_ctx, input, output, 0);
     case GRPC_COMPRESS_GZIP:
-      return zlib_decompress(input, output, 1);
+      return zlib_decompress(exec_ctx, input, output, 1);
     case GRPC_COMPRESS_ALGORITHMS_COUNT:
       break;
   }
diff --git a/src/core/lib/compression/message_compress.h b/src/core/lib/compression/message_compress.h
index 448d36a..7bd3d98 100644
--- a/src/core/lib/compression/message_compress.h
+++ b/src/core/lib/compression/message_compress.h
@@ -40,13 +40,15 @@
 /* compress 'input' to 'output' using 'algorithm'.
    On success, appends compressed slices to output and returns 1.
    On failure, appends uncompressed slices to output and returns 0. */
-int grpc_msg_compress(grpc_compression_algorithm algorithm,
+int grpc_msg_compress(grpc_exec_ctx* exec_ctx,
+                      grpc_compression_algorithm algorithm,
                       grpc_slice_buffer* input, grpc_slice_buffer* output);
 
 /* decompress 'input' to 'output' using 'algorithm'.
    On success, appends slices to output and returns 1.
    On failure, output is unchanged, and returns 0. */
-int grpc_msg_decompress(grpc_compression_algorithm algorithm,
+int grpc_msg_decompress(grpc_exec_ctx* exec_ctx,
+                        grpc_compression_algorithm algorithm,
                         grpc_slice_buffer* input, grpc_slice_buffer* output);
 
 #endif /* GRPC_CORE_LIB_COMPRESSION_MESSAGE_COMPRESS_H */
diff --git a/src/core/lib/http/httpcli.c b/src/core/lib/http/httpcli.c
index fdb8aba..6bab7ef 100644
--- a/src/core/lib/http/httpcli.c
+++ b/src/core/lib/http/httpcli.c
@@ -47,6 +47,7 @@
 #include "src/core/lib/iomgr/resolve_address.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/iomgr/tcp_client.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/support/string.h"
 
 typedef struct {
@@ -111,14 +112,14 @@
   if (req->ep != NULL) {
     grpc_endpoint_destroy(exec_ctx, req->ep);
   }
-  grpc_slice_unref(req->request_text);
+  grpc_slice_unref_internal(exec_ctx, req->request_text);
   gpr_free(req->host);
   gpr_free(req->ssl_host_override);
   grpc_iomgr_unregister_object(&req->iomgr_obj);
-  grpc_slice_buffer_destroy(&req->incoming);
-  grpc_slice_buffer_destroy(&req->outgoing);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &req->incoming);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &req->outgoing);
   GRPC_ERROR_UNREF(req->overall_error);
-  grpc_resource_quota_internal_unref(exec_ctx, req->resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, req->resource_quota);
   gpr_free(req);
 }
 
@@ -178,7 +179,7 @@
 }
 
 static void start_write(grpc_exec_ctx *exec_ctx, internal_request *req) {
-  grpc_slice_ref(req->request_text);
+  grpc_slice_ref_internal(req->request_text);
   grpc_slice_buffer_add(&req->outgoing, req->request_text);
   grpc_endpoint_write(exec_ctx, req->ep, &req->outgoing, &req->done_write);
 }
@@ -265,7 +266,7 @@
   req->context = context;
   req->pollent = pollent;
   req->overall_error = GRPC_ERROR_NONE;
-  req->resource_quota = grpc_resource_quota_internal_ref(resource_quota);
+  req->resource_quota = grpc_resource_quota_ref_internal(resource_quota);
   grpc_closure_init(&req->on_read, on_read, req);
   grpc_closure_init(&req->done_write, done_write, req);
   grpc_slice_buffer_init(&req->incoming);
diff --git a/src/core/lib/iomgr/resource_quota.c b/src/core/lib/iomgr/resource_quota.c
index ddc7a88..eac7c52 100644
--- a/src/core/lib/iomgr/resource_quota.c
+++ b/src/core/lib/iomgr/resource_quota.c
@@ -169,14 +169,14 @@
   rq_reclaim(exec_ctx, resource_quota, false) ||
       rq_reclaim(exec_ctx, resource_quota, true);
 done:
-  grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
 }
 
 static void rq_step_sched(grpc_exec_ctx *exec_ctx,
                           grpc_resource_quota *resource_quota) {
   if (resource_quota->step_scheduled) return;
   resource_quota->step_scheduled = true;
-  grpc_resource_quota_internal_ref(resource_quota);
+  grpc_resource_quota_ref_internal(resource_quota);
   grpc_combiner_execute_finally(exec_ctx, resource_quota->combiner,
                                 &resource_quota->rq_step_closure,
                                 GRPC_ERROR_NONE, false);
@@ -257,7 +257,7 @@
             destructive ? "destructive" : "benign");
   }
   resource_quota->reclaiming = true;
-  grpc_resource_quota_internal_ref(resource_quota);
+  grpc_resource_quota_ref_internal(resource_quota);
   grpc_closure *c = resource_user->reclaimers[destructive];
   resource_user->reclaimers[destructive] = NULL;
   grpc_closure_run(exec_ctx, c, GRPC_ERROR_NONE);
@@ -280,21 +280,10 @@
   gpr_ref(&rc->refs);
 }
 
-static void ru_slice_unref(void *p) {
+static void ru_slice_unref(grpc_exec_ctx *exec_ctx, void *p) {
   ru_slice_refcount *rc = p;
   if (gpr_unref(&rc->refs)) {
-    /* TODO(ctiller): this is dangerous, but I think safe for now:
-       we have no guarantee here that we're at a safe point for creating an
-       execution context, but we have no way of writing this code otherwise.
-       In the future: consider lifting grpc_slice to grpc, and offering an
-       internal_{ref,unref} pair that is execution context aware.
-       Alternatively,
-       make exec_ctx be thread local and 'do the right thing' (whatever that
-       is)
-       if NULL */
-    grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-    grpc_resource_user_free(&exec_ctx, rc->resource_user, rc->size);
-    grpc_exec_ctx_finish(&exec_ctx);
+    grpc_resource_user_free(exec_ctx, rc->resource_user, rc->size);
     gpr_free(rc);
   }
 }
@@ -419,7 +408,7 @@
   a->resource_quota->size += delta;
   a->resource_quota->free_pool += delta;
   rq_step_sched(exec_ctx, a->resource_quota);
-  grpc_resource_quota_internal_unref(exec_ctx, a->resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, a->resource_quota);
   gpr_free(a);
 }
 
@@ -428,7 +417,7 @@
   grpc_resource_quota *resource_quota = rq;
   resource_quota->reclaiming = false;
   rq_step_sched(exec_ctx, resource_quota);
-  grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
 }
 
 /*******************************************************************************
@@ -459,7 +448,7 @@
   return resource_quota;
 }
 
-void grpc_resource_quota_internal_unref(grpc_exec_ctx *exec_ctx,
+void grpc_resource_quota_unref_internal(grpc_exec_ctx *exec_ctx,
                                         grpc_resource_quota *resource_quota) {
   if (gpr_unref(&resource_quota->refs)) {
     grpc_combiner_destroy(exec_ctx, resource_quota->combiner);
@@ -471,11 +460,11 @@
 /* Public API */
 void grpc_resource_quota_unref(grpc_resource_quota *resource_quota) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_resource_quota_internal_unref(&exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(&exec_ctx, resource_quota);
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
-grpc_resource_quota *grpc_resource_quota_internal_ref(
+grpc_resource_quota *grpc_resource_quota_ref_internal(
     grpc_resource_quota *resource_quota) {
   gpr_ref(&resource_quota->refs);
   return resource_quota;
@@ -483,7 +472,7 @@
 
 /* Public API */
 void grpc_resource_quota_ref(grpc_resource_quota *resource_quota) {
-  grpc_resource_quota_internal_ref(resource_quota);
+  grpc_resource_quota_ref_internal(resource_quota);
 }
 
 /* Public API */
@@ -491,7 +480,7 @@
                                 size_t size) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   rq_resize_args *a = gpr_malloc(sizeof(*a));
-  a->resource_quota = grpc_resource_quota_internal_ref(resource_quota);
+  a->resource_quota = grpc_resource_quota_ref_internal(resource_quota);
   a->size = (int64_t)size;
   grpc_closure_init(&a->closure, rq_resize, a);
   grpc_combiner_execute(&exec_ctx, resource_quota->combiner, &a->closure,
@@ -508,7 +497,7 @@
   for (size_t i = 0; i < channel_args->num_args; i++) {
     if (0 == strcmp(channel_args->args[i].key, GRPC_ARG_RESOURCE_QUOTA)) {
       if (channel_args->args[i].type == GRPC_ARG_POINTER) {
-        return grpc_resource_quota_internal_ref(
+        return grpc_resource_quota_ref_internal(
             channel_args->args[i].value.pointer.p);
       } else {
         gpr_log(GPR_DEBUG, GRPC_ARG_RESOURCE_QUOTA " should be a pointer");
@@ -523,7 +512,9 @@
   return rq;
 }
 
-static void rq_destroy(void *rq) { grpc_resource_quota_unref(rq); }
+static void rq_destroy(grpc_exec_ctx *exec_ctx, void *rq) {
+  grpc_resource_quota_unref_internal(exec_ctx, rq);
+}
 
 static int rq_cmp(void *a, void *b) { return GPR_ICMP(a, b); }
 
@@ -540,7 +531,7 @@
                              grpc_resource_quota *resource_quota,
                              const char *name) {
   resource_user->resource_quota =
-      grpc_resource_quota_internal_ref(resource_quota);
+      grpc_resource_quota_ref_internal(resource_quota);
   grpc_closure_init(&resource_user->allocate_closure, &ru_allocate,
                     resource_user);
   grpc_closure_init(&resource_user->add_to_free_pool_closure,
@@ -589,7 +580,7 @@
 
 void grpc_resource_user_destroy(grpc_exec_ctx *exec_ctx,
                                 grpc_resource_user *resource_user) {
-  grpc_resource_quota_internal_unref(exec_ctx, resource_user->resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, resource_user->resource_quota);
   gpr_mu_destroy(&resource_user->mu);
   gpr_free(resource_user->name);
 }
diff --git a/src/core/lib/iomgr/resource_quota.h b/src/core/lib/iomgr/resource_quota.h
index f7e5ca6..f1da739 100644
--- a/src/core/lib/iomgr/resource_quota.h
+++ b/src/core/lib/iomgr/resource_quota.h
@@ -77,9 +77,9 @@
 
 extern int grpc_resource_quota_trace;
 
-grpc_resource_quota *grpc_resource_quota_internal_ref(
+grpc_resource_quota *grpc_resource_quota_ref_internal(
     grpc_resource_quota *resource_quota);
-void grpc_resource_quota_internal_unref(grpc_exec_ctx *exec_ctx,
+void grpc_resource_quota_unref_internal(grpc_exec_ctx *exec_ctx,
                                         grpc_resource_quota *resource_quota);
 grpc_resource_quota *grpc_resource_quota_from_channel_args(
     const grpc_channel_args *channel_args);
diff --git a/src/core/lib/iomgr/tcp_client_posix.c b/src/core/lib/iomgr/tcp_client_posix.c
index bc08c94..3b0fe3b 100644
--- a/src/core/lib/iomgr/tcp_client_posix.c
+++ b/src/core/lib/iomgr/tcp_client_posix.c
@@ -116,7 +116,7 @@
   if (done) {
     gpr_mu_destroy(&ac->mu);
     gpr_free(ac->addr_str);
-    grpc_channel_args_destroy(ac->channel_args);
+    grpc_channel_args_destroy(exec_ctx, ac->channel_args);
     gpr_free(ac);
   }
 }
@@ -136,8 +136,8 @@
             &channel_args->args[i], options);
       } else if (0 ==
                  strcmp(channel_args->args[i].key, GRPC_ARG_RESOURCE_QUOTA)) {
-        grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
-        resource_quota = grpc_resource_quota_internal_ref(
+        grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
+        resource_quota = grpc_resource_quota_ref_internal(
             channel_args->args[i].value.pointer.p);
       }
     }
@@ -145,7 +145,7 @@
 
   grpc_endpoint *ep =
       grpc_tcp_create(fd, resource_quota, tcp_read_chunk_size, addr_str);
-  grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
   return ep;
 }
 
@@ -247,7 +247,7 @@
   if (done) {
     gpr_mu_destroy(&ac->mu);
     gpr_free(ac->addr_str);
-    grpc_channel_args_destroy(ac->channel_args);
+    grpc_channel_args_destroy(exec_ctx, ac->channel_args);
     gpr_free(ac);
   }
   grpc_exec_ctx_sched(exec_ctx, closure, error, NULL);
diff --git a/src/core/lib/iomgr/tcp_client_windows.c b/src/core/lib/iomgr/tcp_client_windows.c
index 4d1e809..4ad417f 100644
--- a/src/core/lib/iomgr/tcp_client_windows.c
+++ b/src/core/lib/iomgr/tcp_client_windows.c
@@ -71,7 +71,7 @@
   int done = (--ac->refs == 0);
   gpr_mu_unlock(&ac->mu);
   if (done) {
-    grpc_resource_quota_internal_unref(exec_ctx, ac->resource_quota);
+    grpc_resource_quota_unref_internal(exec_ctx, ac->resource_quota);
     gpr_mu_destroy(&ac->mu);
     gpr_free(ac->addr_name);
     gpr_free(ac);
@@ -153,8 +153,8 @@
   if (channel_args != NULL) {
     for (size_t i = 0; i < channel_args->num_args; i++) {
       if (0 == strcmp(channel_args->args[i].key, GRPC_ARG_RESOURCE_QUOTA)) {
-        grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
-        resource_quota = grpc_resource_quota_internal_ref(
+        grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
+        resource_quota = grpc_resource_quota_ref_internal(
             channel_args->args[i].value.pointer.p);
       }
     }
@@ -242,7 +242,7 @@
   } else if (sock != INVALID_SOCKET) {
     closesocket(sock);
   }
-  grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
   grpc_exec_ctx_sched(exec_ctx, on_done, final_error, NULL);
 }
 
diff --git a/src/core/lib/iomgr/tcp_posix.c b/src/core/lib/iomgr/tcp_posix.c
index 584fc2f..4bf13be 100644
--- a/src/core/lib/iomgr/tcp_posix.c
+++ b/src/core/lib/iomgr/tcp_posix.c
@@ -56,6 +56,7 @@
 #include "src/core/lib/debug/trace.h"
 #include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 
@@ -131,7 +132,7 @@
 static void tcp_free(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
   grpc_fd_orphan(exec_ctx, tcp->em_fd, tcp->release_fd_cb, tcp->release_fd,
                  "tcp_unref_orphan");
-  grpc_slice_buffer_destroy(&tcp->last_read_buffer);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &tcp->last_read_buffer);
   grpc_resource_user_destroy(exec_ctx, &tcp->resource_user);
   gpr_free(tcp->peer_string);
   gpr_free(tcp);
@@ -178,7 +179,7 @@
   grpc_network_status_unregister_endpoint(ep);
   grpc_tcp *tcp = (grpc_tcp *)ep;
   tcp_maybe_shutdown_resource_user(exec_ctx, tcp);
-  grpc_slice_buffer_reset_and_unref(&tcp->last_read_buffer);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &tcp->last_read_buffer);
   TCP_UNREF(exec_ctx, tcp, "destroy");
 }
 
@@ -245,13 +246,14 @@
       /* We've consumed the edge, request a new one */
       grpc_fd_notify_on_read(exec_ctx, tcp->em_fd, &tcp->read_closure);
     } else {
-      grpc_slice_buffer_reset_and_unref(tcp->incoming_buffer);
+      grpc_slice_buffer_reset_and_unref_internal(exec_ctx,
+                                                 tcp->incoming_buffer);
       call_read_cb(exec_ctx, tcp, GRPC_OS_ERROR(errno, "recvmsg"));
       TCP_UNREF(exec_ctx, tcp, "read");
     }
   } else if (read_bytes == 0) {
     /* 0 read size ==> end of stream */
-    grpc_slice_buffer_reset_and_unref(tcp->incoming_buffer);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx, tcp->incoming_buffer);
     call_read_cb(exec_ctx, tcp, GRPC_ERROR_CREATE("Socket closed"));
     TCP_UNREF(exec_ctx, tcp, "read");
   } else {
@@ -276,8 +278,9 @@
                                      grpc_error *error) {
   grpc_tcp *tcp = tcpp;
   if (error != GRPC_ERROR_NONE) {
-    grpc_slice_buffer_reset_and_unref(tcp->incoming_buffer);
-    grpc_slice_buffer_reset_and_unref(&tcp->last_read_buffer);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx, tcp->incoming_buffer);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx,
+                                               &tcp->last_read_buffer);
     call_read_cb(exec_ctx, tcp, GRPC_ERROR_REF(error));
     TCP_UNREF(exec_ctx, tcp, "read");
   } else {
@@ -302,8 +305,9 @@
   GPR_ASSERT(!tcp->finished_edge);
 
   if (error != GRPC_ERROR_NONE) {
-    grpc_slice_buffer_reset_and_unref(tcp->incoming_buffer);
-    grpc_slice_buffer_reset_and_unref(&tcp->last_read_buffer);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx, tcp->incoming_buffer);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx,
+                                               &tcp->last_read_buffer);
     call_read_cb(exec_ctx, tcp, GRPC_ERROR_REF(error));
     TCP_UNREF(exec_ctx, tcp, "read");
   } else {
@@ -317,7 +321,7 @@
   GPR_ASSERT(tcp->read_cb == NULL);
   tcp->read_cb = cb;
   tcp->incoming_buffer = incoming_buffer;
-  grpc_slice_buffer_reset_and_unref(incoming_buffer);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, incoming_buffer);
   grpc_slice_buffer_swap(incoming_buffer, &tcp->last_read_buffer);
   TCP_REF(tcp, "read");
   if (tcp->finished_edge) {
@@ -578,7 +582,7 @@
   tcp->release_fd = fd;
   tcp->release_fd_cb = done;
   tcp_maybe_shutdown_resource_user(exec_ctx, tcp);
-  grpc_slice_buffer_reset_and_unref(&tcp->last_read_buffer);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &tcp->last_read_buffer);
   TCP_UNREF(exec_ctx, tcp, "destroy");
 }
 
diff --git a/src/core/lib/iomgr/tcp_server_posix.c b/src/core/lib/iomgr/tcp_server_posix.c
index b6fc1e4..1a753d1 100644
--- a/src/core/lib/iomgr/tcp_server_posix.c
+++ b/src/core/lib/iomgr/tcp_server_posix.c
@@ -167,18 +167,18 @@
         s->so_reuseport =
             has_so_reuseport && (args->args[i].value.integer != 0);
       } else {
-        grpc_resource_quota_internal_unref(exec_ctx, s->resource_quota);
+        grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         gpr_free(s);
         return GRPC_ERROR_CREATE(GRPC_ARG_ALLOW_REUSEPORT
                                  " must be an integer");
       }
     } else if (0 == strcmp(GRPC_ARG_RESOURCE_QUOTA, args->args[i].key)) {
       if (args->args[i].type == GRPC_ARG_POINTER) {
-        grpc_resource_quota_internal_unref(exec_ctx, s->resource_quota);
+        grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         s->resource_quota =
-            grpc_resource_quota_internal_ref(args->args[i].value.pointer.p);
+            grpc_resource_quota_ref_internal(args->args[i].value.pointer.p);
       } else {
-        grpc_resource_quota_internal_unref(exec_ctx, s->resource_quota);
+        grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         gpr_free(s);
         return GRPC_ERROR_CREATE(GRPC_ARG_RESOURCE_QUOTA
                                  " must be a pointer to a buffer pool");
@@ -219,7 +219,7 @@
     gpr_free(sp);
   }
 
-  grpc_resource_quota_internal_unref(exec_ctx, s->resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
 
   gpr_free(s);
 }
diff --git a/src/core/lib/iomgr/tcp_server_windows.c b/src/core/lib/iomgr/tcp_server_windows.c
index ae54c70..c2a6d17 100644
--- a/src/core/lib/iomgr/tcp_server_windows.c
+++ b/src/core/lib/iomgr/tcp_server_windows.c
@@ -115,11 +115,11 @@
   for (size_t i = 0; i < (args == NULL ? 0 : args->num_args); i++) {
     if (0 == strcmp(GRPC_ARG_RESOURCE_QUOTA, args->args[i].key)) {
       if (args->args[i].type == GRPC_ARG_POINTER) {
-        grpc_resource_quota_internal_unref(exec_ctx, s->resource_quota);
+        grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         s->resource_quota =
-            grpc_resource_quota_internal_ref(args->args[i].value.pointer.p);
+            grpc_resource_quota_ref_internal(args->args[i].value.pointer.p);
       } else {
-        grpc_resource_quota_internal_unref(exec_ctx, s->resource_quota);
+        grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         gpr_free(s);
         return GRPC_ERROR_CREATE(GRPC_ARG_RESOURCE_QUOTA
                                  " must be a pointer to a buffer pool");
@@ -155,7 +155,7 @@
     grpc_winsocket_destroy(sp->socket);
     gpr_free(sp);
   }
-  grpc_resource_quota_internal_unref(exec_ctx, s->resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
   gpr_free(s);
 }
 
diff --git a/src/core/lib/iomgr/tcp_windows.c b/src/core/lib/iomgr/tcp_windows.c
index f825057..a97b1b2 100644
--- a/src/core/lib/iomgr/tcp_windows.c
+++ b/src/core/lib/iomgr/tcp_windows.c
@@ -190,13 +190,13 @@
       char *utf8_message = gpr_format_message(info->wsa_error);
       error = GRPC_ERROR_CREATE(utf8_message);
       gpr_free(utf8_message);
-      grpc_slice_unref(tcp->read_slice);
+      grpc_slice_unref_internal(exec_ctx, tcp->read_slice);
     } else {
       if (info->bytes_transfered != 0 && !tcp->shutting_down) {
         sub = grpc_slice_sub_no_ref(tcp->read_slice, 0, info->bytes_transfered);
         grpc_slice_buffer_add(tcp->read_slices, sub);
       } else {
-        grpc_slice_unref(tcp->read_slice);
+        grpc_slice_unref_internal(exec_ctx, tcp->read_slice);
         error = GRPC_ERROR_CREATE("End of TCP stream");
       }
     }
@@ -225,7 +225,7 @@
 
   tcp->read_cb = cb;
   tcp->read_slices = read_slices;
-  grpc_slice_buffer_reset_and_unref(read_slices);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, read_slices);
 
   tcp->read_slice = grpc_slice_malloc(8192);
 
diff --git a/src/core/lib/security/credentials/credentials_metadata.c b/src/core/lib/security/credentials/credentials_metadata.c
index e6cb567..84e2b89 100644
--- a/src/core/lib/security/credentials/credentials_metadata.c
+++ b/src/core/lib/security/credentials/credentials_metadata.c
@@ -62,8 +62,8 @@
                                    grpc_slice key, grpc_slice value) {
   if (store == NULL) return;
   store_ensure_capacity(store);
-  store->entries[store->num_entries].key = grpc_slice_ref(key);
-  store->entries[store->num_entries].value = grpc_slice_ref(value);
+  store->entries[store->num_entries].key = grpc_slice_ref_internal(key);
+  store->entries[store->num_entries].value = grpc_slice_ref_internal(value);
   store->num_entries++;
 }
 
@@ -91,8 +91,8 @@
     if (store->entries != NULL) {
       size_t i;
       for (i = 0; i < store->num_entries; i++) {
-        grpc_slice_unref(store->entries[i].key);
-        grpc_slice_unref(store->entries[i].value);
+        grpc_slice_unref_internal(exec_ctx, store->entries[i].key);
+        grpc_slice_unref_internal(exec_ctx, store->entries[i].value);
       }
       gpr_free(store->entries);
     }
diff --git a/src/core/lib/security/credentials/google_default/google_default_credentials.c b/src/core/lib/security/credentials/google_default/google_default_credentials.c
index afe0e3d..5df97e1 100644
--- a/src/core/lib/security/credentials/google_default/google_default_credentials.c
+++ b/src/core/lib/security/credentials/google_default/google_default_credentials.c
@@ -132,7 +132,7 @@
       gpr_time_add(gpr_now(GPR_CLOCK_REALTIME), max_detection_delay),
       grpc_closure_create(on_compute_engine_detection_http_response, &detector),
       &detector.response);
-  grpc_resource_quota_internal_unref(&exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(&exec_ctx, resource_quota);
 
   grpc_exec_ctx_flush(&exec_ctx);
 
@@ -225,7 +225,7 @@
 end:
   GPR_ASSERT((result == NULL) + (error == GRPC_ERROR_NONE) == 1);
   if (creds_path != NULL) gpr_free(creds_path);
-  grpc_slice_unref(creds_data);
+  grpc_slice_unref_internal(exec_ctx, creds_data);
   if (json != NULL) grpc_json_destroy(json);
   *creds = result;
   return error;
diff --git a/src/core/lib/security/credentials/jwt/jwt_verifier.c b/src/core/lib/security/credentials/jwt/jwt_verifier.c
index 42bd89d..d551a7c 100644
--- a/src/core/lib/security/credentials/jwt/jwt_verifier.c
+++ b/src/core/lib/security/credentials/jwt/jwt_verifier.c
@@ -96,7 +96,7 @@
   json = grpc_json_parse_string_with_len((char *)GRPC_SLICE_START_PTR(*buffer),
                                          GRPC_SLICE_LENGTH(*buffer));
   if (json == NULL) {
-    grpc_slice_unref(*buffer);
+    grpc_slice_unref_internal(exec_ctx, *buffer);
     gpr_log(GPR_ERROR, "JSON parsing error.");
   }
   return json;
@@ -133,7 +133,7 @@
 } jose_header;
 
 static void jose_header_destroy(jose_header *h) {
-  grpc_slice_unref(h->buffer);
+  grpc_slice_unref_internal(exec_ctx, h->buffer);
   gpr_free(h);
 }
 
@@ -195,7 +195,7 @@
 
 void grpc_jwt_claims_destroy(grpc_jwt_claims *claims) {
   grpc_json_destroy(claims->json);
-  grpc_slice_unref(claims->buffer);
+  grpc_slice_unref_internal(exec_ctx, claims->buffer);
   gpr_free(claims);
 }
 
@@ -365,8 +365,8 @@
 void verifier_cb_ctx_destroy(verifier_cb_ctx *ctx) {
   if (ctx->audience != NULL) gpr_free(ctx->audience);
   if (ctx->claims != NULL) grpc_jwt_claims_destroy(ctx->claims);
-  grpc_slice_unref(ctx->signature);
-  grpc_slice_unref(ctx->signed_data);
+  grpc_slice_unref_internal(exec_ctx, ctx->signature);
+  grpc_slice_unref_internal(exec_ctx, ctx->signed_data);
   jose_header_destroy(ctx->header);
   for (size_t i = 0; i < HTTP_RESPONSE_COUNT; i++) {
     grpc_http_response_destroy(&ctx->responses[i]);
@@ -459,7 +459,7 @@
   }
   result = BN_bin2bn(GRPC_SLICE_START_PTR(bin),
                      TSI_SIZE_AS_SIZE(GRPC_SLICE_LENGTH(bin)), NULL);
-  grpc_slice_unref(bin);
+  grpc_slice_unref_internal(exec_ctx, bin);
   return result;
 }
 
@@ -667,7 +667,7 @@
       gpr_time_add(gpr_now(GPR_CLOCK_REALTIME), grpc_jwt_verifier_max_delay),
       grpc_closure_create(on_keys_retrieved, ctx),
       &ctx->responses[HTTP_RESPONSE_KEYS]);
-  grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
   grpc_json_destroy(json);
   gpr_free(req.host);
   return;
@@ -779,7 +779,7 @@
       exec_ctx, &ctx->verifier->http_ctx, &ctx->pollent, resource_quota, &req,
       gpr_time_add(gpr_now(GPR_CLOCK_REALTIME), grpc_jwt_verifier_max_delay),
       http_cb, &ctx->responses[rsp_idx]);
-  grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
   gpr_free(req.host);
   gpr_free(req.http.path);
   return;
diff --git a/src/core/lib/security/credentials/oauth2/oauth2_credentials.c b/src/core/lib/security/credentials/oauth2/oauth2_credentials.c
index d980577..09140be 100644
--- a/src/core/lib/security/credentials/oauth2/oauth2_credentials.c
+++ b/src/core/lib/security/credentials/oauth2/oauth2_credentials.c
@@ -315,7 +315,7 @@
   grpc_httpcli_get(exec_ctx, httpcli_context, pollent, resource_quota, &request,
                    deadline, grpc_closure_create(response_cb, metadata_req),
                    &metadata_req->response);
-  grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
 }
 
 grpc_call_credentials *grpc_google_compute_engine_credentials_create(
@@ -372,7 +372,7 @@
                     &request, body, strlen(body), deadline,
                     grpc_closure_create(response_cb, metadata_req),
                     &metadata_req->response);
-  grpc_resource_quota_internal_unref(exec_ctx, resource_quota);
+  grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
   gpr_free(body);
 }
 
diff --git a/src/core/lib/security/credentials/plugin/plugin_credentials.c b/src/core/lib/security/credentials/plugin/plugin_credentials.c
index 61c1086..16cbb17 100644
--- a/src/core/lib/security/credentials/plugin/plugin_credentials.c
+++ b/src/core/lib/security/credentials/plugin/plugin_credentials.c
@@ -100,8 +100,8 @@
       r->cb(&exec_ctx, r->user_data, md_array, num_md, GRPC_CREDENTIALS_OK,
             NULL);
       for (i = 0; i < num_md; i++) {
-        grpc_slice_unref(md_array[i].key);
-        grpc_slice_unref(md_array[i].value);
+        grpc_slice_unref_internal(exec_ctx, md_array[i].key);
+        grpc_slice_unref_internal(exec_ctx, md_array[i].value);
       }
       gpr_free(md_array);
     }
diff --git a/src/core/lib/security/transport/client_auth_filter.c b/src/core/lib/security/transport/client_auth_filter.c
index cd4769e..22ca99e 100644
--- a/src/core/lib/security/transport/client_auth_filter.c
+++ b/src/core/lib/security/transport/client_auth_filter.c
@@ -121,8 +121,8 @@
   for (i = 0; i < num_md; i++) {
     grpc_metadata_batch_add_tail(
         mdb, &calld->md_links[i],
-        grpc_mdelem_from_slices(grpc_slice_ref(md_elems[i].key),
-                                grpc_slice_ref(md_elems[i].value)));
+        grpc_mdelem_from_slices(grpc_slice_ref_internal(md_elems[i].key),
+                                grpc_slice_ref_internal(md_elems[i].value)));
   }
   grpc_call_next_op(exec_ctx, elem, op);
 }
diff --git a/src/core/lib/security/transport/handshake.c b/src/core/lib/security/transport/handshake.c
index 01e7fab..077c1f0 100644
--- a/src/core/lib/security/transport/handshake.c
+++ b/src/core/lib/security/transport/handshake.c
@@ -104,9 +104,9 @@
   if (gpr_unref(&h->refs)) {
     if (h->handshaker != NULL) tsi_handshaker_destroy(h->handshaker);
     if (h->handshake_buffer != NULL) gpr_free(h->handshake_buffer);
-    grpc_slice_buffer_destroy(&h->left_overs);
-    grpc_slice_buffer_destroy(&h->outgoing);
-    grpc_slice_buffer_destroy(&h->incoming);
+    grpc_slice_buffer_destroy_internal(exec_ctx, &h->left_overs);
+    grpc_slice_buffer_destroy_internal(exec_ctx, &h->outgoing);
+    grpc_slice_buffer_destroy_internal(exec_ctx, &h->incoming);
     GRPC_AUTH_CONTEXT_UNREF(h->auth_context, "handshake");
     GRPC_SECURITY_CONNECTOR_UNREF(h->connector, "handshake");
     gpr_free(h);
@@ -213,7 +213,7 @@
 
   to_send =
       grpc_slice_from_copied_buffer((const char *)h->handshake_buffer, offset);
-  grpc_slice_buffer_reset_and_unref(&h->outgoing);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &h->outgoing);
   grpc_slice_buffer_add(&h->outgoing, to_send);
   /* TODO(klempner,jboeuf): This should probably use the client setup
      deadline */
@@ -280,7 +280,7 @@
     grpc_slice_buffer_add(
         &h->left_overs,
         grpc_slice_split_tail(&h->incoming.slices[i], consumed_slice_size));
-    grpc_slice_unref(
+    grpc_slice_unref_internal(exec_ctx, 
         h->incoming.slices[i]); /* split_tail above increments refcount. */
   }
   grpc_slice_buffer_addn(
diff --git a/src/core/lib/security/transport/secure_endpoint.c b/src/core/lib/security/transport/secure_endpoint.c
index fba3314..78037f8 100644
--- a/src/core/lib/security/transport/secure_endpoint.c
+++ b/src/core/lib/security/transport/secure_endpoint.c
@@ -74,11 +74,11 @@
   secure_endpoint *ep = secure_ep;
   grpc_endpoint_destroy(exec_ctx, ep->wrapped_ep);
   tsi_frame_protector_destroy(ep->protector);
-  grpc_slice_buffer_destroy(&ep->leftover_bytes);
-  grpc_slice_unref(ep->read_staging_buffer);
-  grpc_slice_unref(ep->write_staging_buffer);
-  grpc_slice_buffer_destroy(&ep->output_buffer);
-  grpc_slice_buffer_destroy(&ep->source_buffer);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &ep->leftover_bytes);
+  grpc_slice_unref_internal(exec_ctx, ep->read_staging_buffer);
+  grpc_slice_unref_internal(exec_ctx, ep->write_staging_buffer);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &ep->output_buffer);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &ep->source_buffer);
   gpr_mu_destroy(&ep->protector_mu);
   gpr_free(ep);
 }
@@ -154,7 +154,7 @@
   uint8_t *end = GRPC_SLICE_END_PTR(ep->read_staging_buffer);
 
   if (error != GRPC_ERROR_NONE) {
-    grpc_slice_buffer_reset_and_unref(ep->read_buffer);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx, ep->read_buffer);
     call_read_cb(exec_ctx, ep, GRPC_ERROR_CREATE_REFERENCING(
                                    "Secure read failed", &error, 1));
     return;
@@ -209,10 +209,10 @@
 
   /* TODO(yangg) experiment with moving this block after read_cb to see if it
      helps latency */
-  grpc_slice_buffer_reset_and_unref(&ep->source_buffer);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &ep->source_buffer);
 
   if (result != TSI_OK) {
-    grpc_slice_buffer_reset_and_unref(ep->read_buffer);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx, ep->read_buffer);
     call_read_cb(exec_ctx, ep, grpc_set_tsi_error_result(
                                    GRPC_ERROR_CREATE("Unwrap failed"), result));
     return;
@@ -226,7 +226,7 @@
   secure_endpoint *ep = (secure_endpoint *)secure_ep;
   ep->read_cb = cb;
   ep->read_buffer = slices;
-  grpc_slice_buffer_reset_and_unref(ep->read_buffer);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, ep->read_buffer);
 
   SECURE_ENDPOINT_REF(ep, "read");
   if (ep->leftover_bytes.count) {
@@ -258,7 +258,7 @@
   uint8_t *cur = GRPC_SLICE_START_PTR(ep->write_staging_buffer);
   uint8_t *end = GRPC_SLICE_END_PTR(ep->write_staging_buffer);
 
-  grpc_slice_buffer_reset_and_unref(&ep->output_buffer);
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &ep->output_buffer);
 
   if (grpc_trace_secure_endpoint) {
     for (i = 0; i < slices->count; i++) {
@@ -322,7 +322,7 @@
 
   if (result != TSI_OK) {
     /* TODO(yangg) do different things according to the error type? */
-    grpc_slice_buffer_reset_and_unref(&ep->output_buffer);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &ep->output_buffer);
     grpc_exec_ctx_sched(
         exec_ctx, cb,
         grpc_set_tsi_error_result(GRPC_ERROR_CREATE("Wrap failed"), result),
@@ -398,7 +398,7 @@
   grpc_slice_buffer_init(&ep->leftover_bytes);
   for (i = 0; i < leftover_nslices; i++) {
     grpc_slice_buffer_add(&ep->leftover_bytes,
-                          grpc_slice_ref(leftover_slices[i]));
+                          grpc_slice_ref_internal(leftover_slices[i]));
   }
   ep->write_staging_buffer = grpc_slice_malloc(STAGING_BUFFER_SIZE);
   ep->read_staging_buffer = grpc_slice_malloc(STAGING_BUFFER_SIZE);
diff --git a/src/core/lib/security/util/b64.c b/src/core/lib/security/util/b64.c
index 4892e8e..c227889 100644
--- a/src/core/lib/security/util/b64.c
+++ b/src/core/lib/security/util/b64.c
@@ -228,6 +228,6 @@
   return result;
 
 fail:
-  grpc_slice_unref(result);
+  grpc_slice_unref_internal(exec_ctx, result);
   return gpr_empty_slice();
 }
diff --git a/src/core/lib/slice/percent_encoding.c b/src/core/lib/slice/percent_encoding.c
index b9e35f1..c76c58d 100644
--- a/src/core/lib/slice/percent_encoding.c
+++ b/src/core/lib/slice/percent_encoding.c
@@ -35,6 +35,8 @@
 
 #include <grpc/support/log.h>
 
+#include "src/core/lib/slice/slice_internal.h"
+
 const uint8_t grpc_url_percent_encoding_unreserved_bytes[256 / 8] = {
     0x00, 0x00, 0x00, 0x00, 0x00, 0x60, 0xff, 0x03, 0xfe, 0xff, 0xff,
     0x87, 0xfe, 0xff, 0xff, 0x47, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
@@ -66,7 +68,7 @@
   }
   // no unreserved bytes: return the string unmodified
   if (!any_reserved_bytes) {
-    return grpc_slice_ref(slice);
+    return grpc_slice_ref_internal(slice);
   }
   // second pass: actually encode
   grpc_slice out = grpc_slice_malloc(output_length);
@@ -119,7 +121,7 @@
     }
   }
   if (!any_percent_encoded_stuff) {
-    *slice_out = grpc_slice_ref(slice_in);
+    *slice_out = grpc_slice_ref_internal(slice_in);
     return true;
   }
   p = GRPC_SLICE_START_PTR(slice_in);
@@ -158,7 +160,7 @@
     }
   }
   if (!any_percent_encoded_stuff) {
-    return grpc_slice_ref(slice_in);
+    return grpc_slice_ref_internal(slice_in);
   }
   p = GRPC_SLICE_START_PTR(slice_in);
   grpc_slice out = grpc_slice_malloc(out_length);
diff --git a/src/core/lib/slice/slice.c b/src/core/lib/slice/slice.c
index 3dac18d..5b8f71a 100644
--- a/src/core/lib/slice/slice.c
+++ b/src/core/lib/slice/slice.c
@@ -31,12 +31,16 @@
  *
  */
 
+#include "src/core/lib/slice/slice_internal.h"
+
 #include <grpc/slice.h>
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 
 #include <string.h>
 
+#include "src/core/lib/iomgr/exec_ctx.h"
+
 grpc_slice gpr_empty_slice(void) {
   grpc_slice out;
   out.refcount = 0;
@@ -44,25 +48,37 @@
   return out;
 }
 
-grpc_slice grpc_slice_ref(grpc_slice slice) {
+grpc_slice grpc_slice_ref_internal(grpc_slice slice) {
   if (slice.refcount) {
     slice.refcount->ref(slice.refcount);
   }
   return slice;
 }
 
-void grpc_slice_unref(grpc_slice slice) {
+void grpc_slice_unref_internal(grpc_exec_ctx *exec_ctx, grpc_slice slice) {
   if (slice.refcount) {
-    slice.refcount->unref(slice.refcount);
+    slice.refcount->unref(exec_ctx, slice.refcount);
   }
 }
 
+/* Public API */
+grpc_slice grpc_slice_ref(grpc_slice slice) {
+  return grpc_slice_ref_internal(slice);
+}
+
+/* Public API */
+void grpc_slice_unref(grpc_slice slice) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_slice_unref_internal(&exec_ctx, slice);
+  grpc_exec_ctx_finish(&exec_ctx);
+}
+
 /* grpc_slice_from_static_string support structure - a refcount that does
    nothing */
-static void noop_ref_or_unref(void *unused) {}
+static void noop_ref(void *unused) {}
+static void noop_unref(grpc_exec_ctx *exec_ctx, void *unused) {}
 
-static grpc_slice_refcount noop_refcount = {noop_ref_or_unref,
-                                            noop_ref_or_unref};
+static grpc_slice_refcount noop_refcount = {noop_ref, noop_unref};
 
 grpc_slice grpc_slice_from_static_string(const char *s) {
   grpc_slice slice;
@@ -86,7 +102,7 @@
   gpr_ref(&r->refs);
 }
 
-static void new_slice_unref(void *p) {
+static void new_slice_unref(grpc_exec_ctx *exec_ctx, void *p) {
   new_slice_refcount *r = p;
   if (gpr_unref(&r->refs)) {
     r->user_destroy(r->user_data);
@@ -131,7 +147,7 @@
   gpr_ref(&r->refs);
 }
 
-static void new_with_len_unref(void *p) {
+static void new_with_len_unref(grpc_exec_ctx *exec_ctx, void *p) {
   new_with_len_slice_refcount *r = p;
   if (gpr_unref(&r->refs)) {
     r->user_destroy(r->user_data, r->user_length);
@@ -177,7 +193,7 @@
   gpr_ref(&r->refs);
 }
 
-static void malloc_unref(void *p) {
+static void malloc_unref(grpc_exec_ctx *exec_ctx, void *p) {
   malloc_refcount *r = p;
   if (gpr_unref(&r->refs)) {
     gpr_free(r);
diff --git a/src/core/lib/slice/slice_buffer.c b/src/core/lib/slice/slice_buffer.c
index 990ef12..872bd10 100644
--- a/src/core/lib/slice/slice_buffer.c
+++ b/src/core/lib/slice/slice_buffer.c
@@ -40,6 +40,8 @@
 #include <grpc/support/log.h>
 #include <grpc/support/useful.h>
 
+#include "src/core/lib/slice/slice_internal.h"
+
 /* grow a buffer; requires GRPC_SLICE_BUFFER_INLINE_ELEMENTS > 1 */
 #define GROW(x) (3 * (x) / 2)
 
@@ -63,13 +65,23 @@
   sb->slices = sb->inlined;
 }
 
-void grpc_slice_buffer_destroy(grpc_slice_buffer *sb) {
-  grpc_slice_buffer_reset_and_unref(sb);
+void grpc_slice_buffer_destroy_internal(grpc_exec_ctx *exec_ctx,
+                                        grpc_slice_buffer *sb) {
+  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, sb);
   if (sb->slices != sb->inlined) {
     gpr_free(sb->slices);
   }
 }
 
+void grpc_slice_buffer_destroy(grpc_slice_buffer *sb) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_slice_buffer_reset_and_unref_internal(&exec_ctx, sb);
+  if (sb->slices != sb->inlined) {
+    gpr_free(sb->slices);
+  }
+  grpc_exec_ctx_finish(&exec_ctx);
+}
+
 uint8_t *grpc_slice_buffer_tiny_add(grpc_slice_buffer *sb, size_t n) {
   grpc_slice *back;
   uint8_t *out;
@@ -154,17 +166,24 @@
   }
 }
 
-void grpc_slice_buffer_reset_and_unref(grpc_slice_buffer *sb) {
+void grpc_slice_buffer_reset_and_unref_internal(grpc_exec_ctx *exec_ctx,
+                                                grpc_slice_buffer *sb) {
   size_t i;
 
   for (i = 0; i < sb->count; i++) {
-    grpc_slice_unref(sb->slices[i]);
+    grpc_slice_unref_internal(exec_ctx, sb->slices[i]);
   }
 
   sb->count = 0;
   sb->length = 0;
 }
 
+void grpc_slice_buffer_reset_and_unref(grpc_slice_buffer *sb) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_slice_buffer_reset_and_unref_internal(&exec_ctx, sb);
+  grpc_exec_ctx_finish(&exec_ctx);
+}
+
 void grpc_slice_buffer_swap(grpc_slice_buffer *a, grpc_slice_buffer *b) {
   GPR_SWAP(size_t, a->count, b->count);
   GPR_SWAP(size_t, a->capacity, b->capacity);
diff --git a/src/core/lib/slice/slice_internal.h b/src/core/lib/slice/slice_internal.h
new file mode 100644
index 0000000..72b0a59
--- /dev/null
+++ b/src/core/lib/slice/slice_internal.h
@@ -0,0 +1,49 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_CORE_LIB_SUPPORT_SLICE_INTERNAL_H
+#define GRPC_CORE_LIB_SUPPORT_SLICE_INTERNAL_H
+
+#include <grpc/slice.h>
+#include <grpc/slice_buffer.h>
+
+#include "src/core/lib/iomgr/exec_ctx.h"
+
+grpc_slice grpc_slice_ref_internal(grpc_slice slice);
+void grpc_slice_unref_internal(grpc_exec_ctx *exec_ctx, grpc_slice slice);
+void grpc_slice_buffer_reset_and_unref_internal(grpc_exec_ctx *exec_ctx,
+                                                grpc_slice_buffer *sb);
+void grpc_slice_buffer_destroy_internal(grpc_exec_ctx *exec_ctx,
+                                        grpc_slice_buffer *sb);
+
+#endif
diff --git a/src/core/lib/slice/slice_string_helpers.c b/src/core/lib/slice/slice_string_helpers.c
index 4731762..839c366 100644
--- a/src/core/lib/slice/slice_string_helpers.c
+++ b/src/core/lib/slice/slice_string_helpers.c
@@ -37,6 +37,7 @@
 
 #include <grpc/support/log.h>
 
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/support/string.h"
 
 char *grpc_dump_slice(grpc_slice s, uint32_t flags) {
@@ -84,6 +85,6 @@
     grpc_slice_buffer_add_indexed(
         dst, grpc_slice_sub(str, end + sep_len, GRPC_SLICE_LENGTH(str)));
   } else { /* no sep found, add whole input */
-    grpc_slice_buffer_add_indexed(dst, grpc_slice_ref(str));
+    grpc_slice_buffer_add_indexed(dst, grpc_slice_ref_internal(str));
   }
 }
diff --git a/src/core/lib/surface/byte_buffer.c b/src/core/lib/surface/byte_buffer.c
index d646591..c8e2fdf 100644
--- a/src/core/lib/surface/byte_buffer.c
+++ b/src/core/lib/surface/byte_buffer.c
@@ -35,6 +35,8 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 
+#include "src/core/lib/slice/slice_internal.h"
+
 grpc_byte_buffer *grpc_raw_byte_buffer_create(grpc_slice *slices,
                                               size_t nslices) {
   return grpc_raw_compressed_byte_buffer_create(slices, nslices,
@@ -50,7 +52,7 @@
   bb->data.raw.compression = compression;
   grpc_slice_buffer_init(&bb->data.raw.slice_buffer);
   for (i = 0; i < nslices; i++) {
-    grpc_slice_ref(slices[i]);
+    grpc_slice_ref_internal(slices[i]);
     grpc_slice_buffer_add(&bb->data.raw.slice_buffer, slices[i]);
   }
   return bb;
@@ -82,12 +84,14 @@
 
 void grpc_byte_buffer_destroy(grpc_byte_buffer *bb) {
   if (!bb) return;
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   switch (bb->type) {
     case GRPC_BB_RAW:
-      grpc_slice_buffer_destroy(&bb->data.raw.slice_buffer);
+      grpc_slice_buffer_destroy_internal(&exec_ctx, &bb->data.raw.slice_buffer);
       break;
   }
   gpr_free(bb);
+  grpc_exec_ctx_finish(&exec_ctx);
 }
 
 size_t grpc_byte_buffer_length(grpc_byte_buffer *bb) {
diff --git a/src/core/lib/surface/byte_buffer_reader.c b/src/core/lib/surface/byte_buffer_reader.c
index 0089959..1a6ccda 100644
--- a/src/core/lib/surface/byte_buffer_reader.c
+++ b/src/core/lib/surface/byte_buffer_reader.c
@@ -42,6 +42,7 @@
 #include <grpc/support/log.h>
 
 #include "src/core/lib/compression/message_compress.h"
+#include "src/core/lib/slice/slice_internal.h"
 
 static int is_compressed(grpc_byte_buffer *buffer) {
   switch (buffer->type) {
@@ -56,13 +57,15 @@
 
 int grpc_byte_buffer_reader_init(grpc_byte_buffer_reader *reader,
                                  grpc_byte_buffer *buffer) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_slice_buffer decompressed_slices_buffer;
   reader->buffer_in = buffer;
   switch (reader->buffer_in->type) {
     case GRPC_BB_RAW:
       grpc_slice_buffer_init(&decompressed_slices_buffer);
       if (is_compressed(reader->buffer_in)) {
-        if (grpc_msg_decompress(reader->buffer_in->data.raw.compression,
+        if (grpc_msg_decompress(&exec_ctx,
+                                reader->buffer_in->data.raw.compression,
                                 &reader->buffer_in->data.raw.slice_buffer,
                                 &decompressed_slices_buffer) == 0) {
           gpr_log(GPR_ERROR,
@@ -76,13 +79,15 @@
               grpc_raw_byte_buffer_create(decompressed_slices_buffer.slices,
                                           decompressed_slices_buffer.count);
         }
-        grpc_slice_buffer_destroy(&decompressed_slices_buffer);
+        grpc_slice_buffer_destroy_internal(&exec_ctx,
+                                           &decompressed_slices_buffer);
       } else { /* not compressed, use the input buffer as output */
         reader->buffer_out = reader->buffer_in;
       }
       reader->current.index = 0;
       break;
   }
+  grpc_exec_ctx_finish(&exec_ctx);
   return 1;
 }
 
@@ -104,7 +109,8 @@
       grpc_slice_buffer *slice_buffer;
       slice_buffer = &reader->buffer_out->data.raw.slice_buffer;
       if (reader->current.index < slice_buffer->count) {
-        *slice = grpc_slice_ref(slice_buffer->slices[reader->current.index]);
+        *slice = grpc_slice_ref_internal(
+            slice_buffer->slices[reader->current.index]);
         reader->current.index += 1;
         return 1;
       }
@@ -121,12 +127,14 @@
   grpc_slice out_slice = grpc_slice_malloc(input_size);
   uint8_t *const outbuf = GRPC_SLICE_START_PTR(out_slice); /* just an alias */
 
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   while (grpc_byte_buffer_reader_next(reader, &in_slice) != 0) {
     const size_t slice_length = GRPC_SLICE_LENGTH(in_slice);
     memcpy(&(outbuf[bytes_read]), GRPC_SLICE_START_PTR(in_slice), slice_length);
     bytes_read += slice_length;
-    grpc_slice_unref(in_slice);
+    grpc_slice_unref_internal(&exec_ctx, in_slice);
     GPR_ASSERT(bytes_read <= input_size);
   }
+  grpc_exec_ctx_finish(&exec_ctx);
   return out_slice;
 }
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index 62c0ec8..be568fe 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -49,6 +49,7 @@
 #include "src/core/lib/compression/algorithm_metadata.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/surface/api_trace.h"
@@ -225,12 +226,12 @@
 static void receiving_slice_ready(grpc_exec_ctx *exec_ctx, void *bctlp,
                                   grpc_error *error);
 
-grpc_error *grpc_call_create(const grpc_call_create_args *args,
+grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
+                             const grpc_call_create_args *args,
                              grpc_call **out_call) {
   size_t i, j;
   grpc_channel_stack *channel_stack =
       grpc_channel_get_channel_stack(args->channel);
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_call *call;
   GPR_TIMER_BEGIN("grpc_call_create", 0);
   call = gpr_malloc(sizeof(grpc_call) + channel_stack->call_stack_size);
@@ -313,14 +314,14 @@
   GRPC_CHANNEL_INTERNAL_REF(args->channel, "call");
   /* initial refcount dropped by grpc_call_destroy */
   grpc_error *error =
-      grpc_call_stack_init(&exec_ctx, channel_stack, 1, destroy_call, call,
+      grpc_call_stack_init(exec_ctx, channel_stack, 1, destroy_call, call,
                            call->context, args->server_transport_data, path,
                            send_deadline, CALL_STACK_FROM_CALL(call));
   if (error != GRPC_ERROR_NONE) {
     grpc_status_code status;
     const char *error_str;
     grpc_error_get_status(error, &status, &error_str);
-    close_with_status(&exec_ctx, call, status, error_str);
+    close_with_status(exec_ctx, call, status, error_str);
   }
   if (args->cq != NULL) {
     GPR_ASSERT(
@@ -336,12 +337,11 @@
   }
   if (!grpc_polling_entity_is_empty(&call->pollent)) {
     grpc_call_stack_set_pollset_or_pollset_set(
-        &exec_ctx, CALL_STACK_FROM_CALL(call), &call->pollent);
+        exec_ctx, CALL_STACK_FROM_CALL(call), &call->pollent);
   }
 
-  if (path != NULL) GRPC_MDSTR_UNREF(path);
+  if (path != NULL) GRPC_MDSTR_UNREF(exec_ctx, path);
 
-  grpc_exec_ctx_finish(&exec_ctx);
   GPR_TIMER_END("grpc_call_create", 0);
   return error;
 }
@@ -402,7 +402,7 @@
   GPR_TIMER_BEGIN("destroy_call", 0);
   for (i = 0; i < 2; i++) {
     grpc_metadata_batch_destroy(
-        &c->metadata_batch[1 /* is_receiving */][i /* is_initial */]);
+        exec_ctx, &c->metadata_batch[1 /* is_receiving */][i /* is_initial */]);
   }
   if (c->receiving_stream != NULL) {
     grpc_byte_stream_destroy(exec_ctx, c->receiving_stream);
@@ -410,11 +410,11 @@
   gpr_mu_destroy(&c->mu);
   for (i = 0; i < STATUS_SOURCE_COUNT; i++) {
     if (c->status[i].details) {
-      GRPC_MDSTR_UNREF(c->status[i].details);
+      GRPC_MDSTR_UNREF(exec_ctx, c->status[i].details);
     }
   }
   for (ii = 0; ii < c->send_extra_metadata_count; ii++) {
-    GRPC_MDELEM_UNREF(c->send_extra_metadata[ii].md);
+    GRPC_MDELEM_UNREF(exec_ctx, c->send_extra_metadata[ii].md);
   }
   for (i = 0; i < GRPC_CONTEXT_COUNT; i++) {
     if (c->context[i].destroy) {
@@ -442,22 +442,22 @@
   call->status[source].code = (grpc_status_code)status;
 }
 
-static void set_status_details(grpc_call *call, status_source source,
-                               grpc_mdstr *status) {
+static void set_status_details(grpc_exec_ctx *exec_ctx, grpc_call *call,
+                               status_source source, grpc_mdstr *status) {
   if (call->status[source].details != NULL) {
-    GRPC_MDSTR_UNREF(status);
+    GRPC_MDSTR_UNREF(exec_ctx, status);
   } else {
     call->status[source].details = status;
   }
 }
 
-static void set_status_from_error(grpc_call *call, status_source source,
-                                  grpc_error *error) {
+static void set_status_from_error(grpc_exec_ctx *exec_ctx, grpc_call *call,
+                                  status_source source, grpc_error *error) {
   grpc_status_code status;
   const char *msg;
   grpc_error_get_status(error, &status, &msg);
   set_status_code(call, source, (uint32_t)status);
-  set_status_details(call, source, grpc_mdstr_from_string(msg));
+  set_status_details(exec_ctx, call, source, grpc_mdstr_from_string(msg));
 }
 
 static void set_incoming_compression_algorithm(
@@ -491,7 +491,8 @@
 
 static void destroy_encodings_accepted_by_peer(void *p) { return; }
 
-static void set_encodings_accepted_by_peer(grpc_call *call, grpc_mdelem *mdel) {
+static void set_encodings_accepted_by_peer(grpc_exec_ctx *exec_ctx,
+                                           grpc_call *call, grpc_mdelem *mdel) {
   size_t i;
   grpc_compression_algorithm algorithm;
   grpc_slice_buffer accept_encoding_parts;
@@ -531,7 +532,7 @@
     }
   }
 
-  grpc_slice_buffer_destroy(&accept_encoding_parts);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &accept_encoding_parts);
 
   grpc_mdelem_set_user_data(
       mdel, destroy_encodings_accepted_by_peer,
@@ -589,12 +590,10 @@
   return res;
 }
 
-static int prepare_application_metadata(grpc_call *call, int count,
-                                        grpc_metadata *metadata,
-                                        int is_trailing,
-                                        int prepend_extra_metadata,
-                                        grpc_metadata *additional_metadata,
-                                        int additional_metadata_count) {
+static int prepare_application_metadata(
+    grpc_exec_ctx *exec_ctx, grpc_call *call, int count,
+    grpc_metadata *metadata, int is_trailing, int prepend_extra_metadata,
+    grpc_metadata *additional_metadata, int additional_metadata_count) {
   int total_count = count + additional_metadata_count;
   int i;
   grpc_metadata_batch *batch =
@@ -605,7 +604,7 @@
     grpc_linked_mdelem *l = (grpc_linked_mdelem *)&md->internal_data;
     GPR_ASSERT(sizeof(grpc_linked_mdelem) == sizeof(md->internal_data));
     l->md = grpc_mdelem_from_string_and_buffer(
-        md->key, (const uint8_t *)md->value, md->value_length);
+        exec_ctx, md->key, (const uint8_t *)md->value, md->value_length);
     if (!grpc_header_key_is_legal(grpc_mdstr_as_c_string(l->md->key),
                                   GRPC_MDSTR_LENGTH(l->md->key))) {
       gpr_log(GPR_ERROR, "attempt to send invalid metadata key: %s",
@@ -625,7 +624,7 @@
       const grpc_metadata *md =
           get_md_elem(metadata, additional_metadata, j, count);
       grpc_linked_mdelem *l = (grpc_linked_mdelem *)&md->internal_data;
-      GRPC_MDELEM_UNREF(l->md);
+      GRPC_MDELEM_UNREF(exec_ctx, l->md);
     }
     return 0;
   }
@@ -808,7 +807,8 @@
 
 static grpc_call_error terminate_with_status(grpc_exec_ctx *exec_ctx,
                                              termination_closure *tc) {
-  set_status_from_error(tc->call, STATUS_FROM_API_OVERRIDE, tc->error);
+  set_status_from_error(exec_ctx, tc->call, STATUS_FROM_API_OVERRIDE,
+                        tc->error);
 
   if (tc->type == TC_CANCEL) {
     grpc_closure_init(&tc->closure, send_cancel, tc);
@@ -925,7 +925,8 @@
   return algorithm;
 }
 
-static grpc_mdelem *recv_common_filter(grpc_call *call, grpc_mdelem *elem) {
+static grpc_mdelem *recv_common_filter(grpc_exec_ctx *exec_ctx, grpc_call *call,
+                                       grpc_mdelem *elem) {
   if (elem->key == GRPC_MDSTR_GRPC_STATUS) {
     GPR_TIMER_BEGIN("status", 0);
     set_status_code(call, STATUS_FROM_WIRE, decode_status(elem));
@@ -933,7 +934,8 @@
     return NULL;
   } else if (elem->key == GRPC_MDSTR_GRPC_MESSAGE) {
     GPR_TIMER_BEGIN("status-details", 0);
-    set_status_details(call, STATUS_FROM_WIRE, GRPC_MDSTR_REF(elem->value));
+    set_status_details(exec_ctx, call, STATUS_FROM_WIRE,
+                       GRPC_MDSTR_REF(elem->value));
     GPR_TIMER_END("status-details", 0);
     return NULL;
   }
@@ -959,33 +961,38 @@
   return elem;
 }
 
-static grpc_mdelem *recv_initial_filter(void *callp, grpc_mdelem *elem) {
-  grpc_call *call = callp;
-  elem = recv_common_filter(call, elem);
+typedef struct {
+  grpc_exec_ctx *exec_ctx;
+  grpc_call *call;
+} recv_filter_args;
+
+static grpc_mdelem *recv_initial_filter(void *args, grpc_mdelem *elem) {
+  recv_filter_args *a = args;
+  elem = recv_common_filter(a->exec_ctx, a->call, elem);
   if (elem == NULL) {
     return NULL;
   } else if (elem->key == GRPC_MDSTR_GRPC_ENCODING) {
     GPR_TIMER_BEGIN("incoming_compression_algorithm", 0);
-    set_incoming_compression_algorithm(call, decode_compression(elem));
+    set_incoming_compression_algorithm(a->call, decode_compression(elem));
     GPR_TIMER_END("incoming_compression_algorithm", 0);
     return NULL;
   } else if (elem->key == GRPC_MDSTR_GRPC_ACCEPT_ENCODING) {
     GPR_TIMER_BEGIN("encodings_accepted_by_peer", 0);
-    set_encodings_accepted_by_peer(call, elem);
+    set_encodings_accepted_by_peer(a->exec_ctx, a->call, elem);
     GPR_TIMER_END("encodings_accepted_by_peer", 0);
     return NULL;
   } else {
-    return publish_app_metadata(call, elem, 0);
+    return publish_app_metadata(a->call, elem, 0);
   }
 }
 
-static grpc_mdelem *recv_trailing_filter(void *callp, grpc_mdelem *elem) {
-  grpc_call *call = callp;
-  elem = recv_common_filter(call, elem);
+static grpc_mdelem *recv_trailing_filter(void *args, grpc_mdelem *elem) {
+  recv_filter_args *a = args;
+  elem = recv_common_filter(a->exec_ctx, a->call, elem);
   if (elem == NULL) {
     return NULL;
   } else {
-    return publish_app_metadata(call, elem, 1);
+    return publish_app_metadata(a->call, elem, 1);
   }
 }
 
@@ -1231,7 +1238,8 @@
   if (error == GRPC_ERROR_NONE) {
     grpc_metadata_batch *md =
         &call->metadata_batch[1 /* is_receiving */][0 /* is_trailing */];
-    grpc_metadata_batch_filter(md, recv_initial_filter, call);
+    recv_filter_args args = {exec_ctx, call};
+    grpc_metadata_batch_filter(exec_ctx, md, recv_initial_filter, &args);
 
     GPR_TIMER_BEGIN("validate_filtered_metadata", 0);
     validate_filtered_metadata(exec_ctx, bctl);
@@ -1275,14 +1283,15 @@
   intptr_t status;
   if (error != GRPC_ERROR_NONE &&
       grpc_error_get_int(error, GRPC_ERROR_INT_GRPC_STATUS, &status)) {
-    set_status_from_error(call, STATUS_FROM_CORE, error);
+    set_status_from_error(exec_ctx, call, STATUS_FROM_CORE, error);
   }
 
   if (bctl->send_initial_metadata) {
     if (error != GRPC_ERROR_NONE) {
-      set_status_from_error(call, STATUS_FROM_CORE, error);
+      set_status_from_error(exec_ctx, call, STATUS_FROM_CORE, error);
     }
     grpc_metadata_batch_destroy(
+        exec_ctx,
         &call->metadata_batch[0 /* is_receiving */][0 /* is_trailing */]);
   }
   if (bctl->send_message) {
@@ -1290,12 +1299,14 @@
   }
   if (bctl->send_final_op) {
     grpc_metadata_batch_destroy(
+        exec_ctx,
         &call->metadata_batch[0 /* is_receiving */][1 /* is_trailing */]);
   }
   if (bctl->recv_final_op) {
     grpc_metadata_batch *md =
         &call->metadata_batch[1 /* is_receiving */][1 /* is_trailing */];
-    grpc_metadata_batch_filter(md, recv_trailing_filter, call);
+    recv_filter_args args = {exec_ctx, call};
+    grpc_metadata_batch_filter(exec_ctx, md, recv_trailing_filter, &args);
 
     call->received_final_op = true;
     /* propagate cancellation to any interested children */
@@ -1432,7 +1443,7 @@
         bctl->send_initial_metadata = 1;
         call->sent_initial_metadata = 1;
         if (!prepare_application_metadata(
-                call, (int)op->data.send_initial_metadata.count,
+                exec_ctx, call, (int)op->data.send_initial_metadata.count,
                 op->data.send_initial_metadata.metadata, 0, call->is_client,
                 &compression_md, (int)additional_metadata_count)) {
           error = GRPC_CALL_ERROR_INVALID_METADATA;
@@ -1506,15 +1517,15 @@
         call->sent_final_op = 1;
         call->send_extra_metadata_count = 1;
         call->send_extra_metadata[0].md = grpc_channel_get_reffed_status_elem(
-            call->channel, op->data.send_status_from_server.status);
+            exec_ctx, call->channel, op->data.send_status_from_server.status);
         if (op->data.send_status_from_server.status_details != NULL) {
           call->send_extra_metadata[1].md = grpc_mdelem_from_metadata_strings(
-              GRPC_MDSTR_GRPC_MESSAGE,
+              exec_ctx, GRPC_MDSTR_GRPC_MESSAGE,
               grpc_mdstr_from_string(
                   op->data.send_status_from_server.status_details));
           call->send_extra_metadata_count++;
           set_status_details(
-              call, STATUS_FROM_API_OVERRIDE,
+              exec_ctx, call, STATUS_FROM_API_OVERRIDE,
               GRPC_MDSTR_REF(call->send_extra_metadata[1].md->value));
         }
         if (op->data.send_status_from_server.status != GRPC_STATUS_OK) {
@@ -1522,7 +1533,7 @@
                           (uint32_t)op->data.send_status_from_server.status);
         }
         if (!prepare_application_metadata(
-                call,
+                exec_ctx, call,
                 (int)op->data.send_status_from_server.trailing_metadata_count,
                 op->data.send_status_from_server.trailing_metadata, 1, 1, NULL,
                 0)) {
@@ -1647,7 +1658,7 @@
   /* reverse any mutations that occured */
   if (bctl->send_initial_metadata) {
     call->sent_initial_metadata = 0;
-    grpc_metadata_batch_clear(&call->metadata_batch[0][0]);
+    grpc_metadata_batch_clear(exec_ctx, &call->metadata_batch[0][0]);
   }
   if (bctl->send_message) {
     call->sending_message = 0;
@@ -1655,7 +1666,7 @@
   }
   if (bctl->send_final_op) {
     call->sent_final_op = 0;
-    grpc_metadata_batch_clear(&call->metadata_batch[0][1]);
+    grpc_metadata_batch_clear(exec_ctx, &call->metadata_batch[0][1]);
   }
   if (bctl->recv_initial_metadata) {
     call->received_initial_metadata = 0;
diff --git a/src/core/lib/surface/call.h b/src/core/lib/surface/call.h
index 18af41b..233340c 100644
--- a/src/core/lib/surface/call.h
+++ b/src/core/lib/surface/call.h
@@ -70,7 +70,8 @@
 /* Create a new call based on \a args.
    Regardless of success or failure, always returns a valid new call into *call
    */
-grpc_error *grpc_call_create(const grpc_call_create_args *args,
+grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
+                             const grpc_call_create_args *args,
                              grpc_call **call);
 
 void grpc_call_set_completion_queue(grpc_exec_ctx *exec_ctx, grpc_call *call,
diff --git a/src/core/lib/surface/channel.c b/src/core/lib/surface/channel.c
index 92d783b..8261739 100644
--- a/src/core/lib/surface/channel.c
+++ b/src/core/lib/surface/channel.c
@@ -89,13 +89,14 @@
   bool is_client = grpc_channel_stack_type_is_client(channel_stack_type);
 
   grpc_channel_stack_builder *builder = grpc_channel_stack_builder_create();
-  grpc_channel_stack_builder_set_channel_arguments(builder, input_args);
+  grpc_channel_stack_builder_set_channel_arguments(exec_ctx, builder,
+                                                   input_args);
   grpc_channel_stack_builder_set_target(builder, target);
   grpc_channel_stack_builder_set_transport(builder, optional_transport);
   grpc_channel *channel;
   grpc_channel_args *args;
   if (!grpc_channel_init_create_stack(exec_ctx, builder, channel_stack_type)) {
-    grpc_channel_stack_builder_destroy(builder);
+    grpc_channel_stack_builder_destroy(exec_ctx, builder);
     return NULL;
   } else {
     args = grpc_channel_args_copy(
@@ -120,10 +121,10 @@
         } else {
           if (channel->default_authority) {
             /* setting this takes precedence over anything else */
-            GRPC_MDELEM_UNREF(channel->default_authority);
+            GRPC_MDELEM_UNREF(exec_ctx, channel->default_authority);
           }
           channel->default_authority = grpc_mdelem_from_strings(
-              ":authority", args->args[i].value.string);
+              exec_ctx, ":authority", args->args[i].value.string);
         }
       } else if (0 ==
                  strcmp(args->args[i].key, GRPC_SSL_TARGET_NAME_OVERRIDE_ARG)) {
@@ -138,7 +139,7 @@
                     GRPC_SSL_TARGET_NAME_OVERRIDE_ARG);
           } else {
             channel->default_authority = grpc_mdelem_from_strings(
-                ":authority", args->args[i].value.string);
+                exec_ctx, ":authority", args->args[i].value.string);
           }
         }
       } else if (0 == strcmp(args->args[i].key,
@@ -164,7 +165,7 @@
             0x1; /* always support no compression */
       }
     }
-    grpc_channel_args_destroy(args);
+    grpc_channel_args_destroy(exec_ctx, args);
   }
 
   return channel;
@@ -176,10 +177,10 @@
 }
 
 static grpc_call *grpc_channel_create_call_internal(
-    grpc_channel *channel, grpc_call *parent_call, uint32_t propagation_mask,
-    grpc_completion_queue *cq, grpc_pollset_set *pollset_set_alternative,
-    grpc_mdelem *path_mdelem, grpc_mdelem *authority_mdelem,
-    gpr_timespec deadline) {
+    grpc_exec_ctx *exec_ctx, grpc_channel *channel, grpc_call *parent_call,
+    uint32_t propagation_mask, grpc_completion_queue *cq,
+    grpc_pollset_set *pollset_set_alternative, grpc_mdelem *path_mdelem,
+    grpc_mdelem *authority_mdelem, gpr_timespec deadline) {
   grpc_mdelem *send_metadata[2];
   size_t num_metadata = 0;
 
@@ -206,7 +207,7 @@
   args.send_deadline = deadline;
 
   grpc_call *call;
-  GRPC_LOG_IF_ERROR("call_create", grpc_call_create(&args, &call));
+  GRPC_LOG_IF_ERROR("call_create", grpc_call_create(exec_ctx, &args, &call));
   return call;
 }
 
@@ -227,26 +228,30 @@
       (channel, parent_call, (unsigned)propagation_mask, cq, method, host,
        deadline.tv_sec, deadline.tv_nsec, (int)deadline.clock_type, reserved));
   GPR_ASSERT(!reserved);
-  return grpc_channel_create_call_internal(
-      channel, parent_call, propagation_mask, cq, NULL,
-      grpc_mdelem_from_metadata_strings(GRPC_MDSTR_PATH,
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_call *call = grpc_channel_create_call_internal(
+      &exec_ctx, channel, parent_call, propagation_mask, cq, NULL,
+      grpc_mdelem_from_metadata_strings(&exec_ctx, GRPC_MDSTR_PATH,
                                         grpc_mdstr_from_string(method)),
-      host ? grpc_mdelem_from_metadata_strings(GRPC_MDSTR_AUTHORITY,
+      host ? grpc_mdelem_from_metadata_strings(&exec_ctx, GRPC_MDSTR_AUTHORITY,
                                                grpc_mdstr_from_string(host))
            : NULL,
       deadline);
+  grpc_exec_ctx_finish(&exec_ctx);
+  return call;
 }
 
 grpc_call *grpc_channel_create_pollset_set_call(
-    grpc_channel *channel, grpc_call *parent_call, uint32_t propagation_mask,
-    grpc_pollset_set *pollset_set, const char *method, const char *host,
-    gpr_timespec deadline, void *reserved) {
+    grpc_exec_ctx *exec_ctx, grpc_channel *channel, grpc_call *parent_call,
+    uint32_t propagation_mask, grpc_pollset_set *pollset_set,
+    const char *method, const char *host, gpr_timespec deadline,
+    void *reserved) {
   GPR_ASSERT(!reserved);
   return grpc_channel_create_call_internal(
-      channel, parent_call, propagation_mask, NULL, pollset_set,
-      grpc_mdelem_from_metadata_strings(GRPC_MDSTR_PATH,
+      exec_ctx, channel, parent_call, propagation_mask, NULL, pollset_set,
+      grpc_mdelem_from_metadata_strings(exec_ctx, GRPC_MDSTR_PATH,
                                         grpc_mdstr_from_string(method)),
-      host ? grpc_mdelem_from_metadata_strings(GRPC_MDSTR_AUTHORITY,
+      host ? grpc_mdelem_from_metadata_strings(exec_ctx, GRPC_MDSTR_AUTHORITY,
                                                grpc_mdstr_from_string(host))
            : NULL,
       deadline);
@@ -259,15 +264,18 @@
       "grpc_channel_register_call(channel=%p, method=%s, host=%s, reserved=%p)",
       4, (channel, method, host, reserved));
   GPR_ASSERT(!reserved);
-  rc->path = grpc_mdelem_from_metadata_strings(GRPC_MDSTR_PATH,
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  rc->path = grpc_mdelem_from_metadata_strings(&exec_ctx, GRPC_MDSTR_PATH,
                                                grpc_mdstr_from_string(method));
-  rc->authority = host ? grpc_mdelem_from_metadata_strings(
-                             GRPC_MDSTR_AUTHORITY, grpc_mdstr_from_string(host))
-                       : NULL;
+  rc->authority =
+      host ? grpc_mdelem_from_metadata_strings(&exec_ctx, GRPC_MDSTR_AUTHORITY,
+                                               grpc_mdstr_from_string(host))
+           : NULL;
   gpr_mu_lock(&channel->registered_call_mu);
   rc->next = channel->registered_calls;
   channel->registered_calls = rc;
   gpr_mu_unlock(&channel->registered_call_mu);
+  grpc_exec_ctx_finish(&exec_ctx);
   return rc;
 }
 
@@ -287,10 +295,13 @@
           registered_call_handle, deadline.tv_sec, deadline.tv_nsec,
           (int)deadline.clock_type, reserved));
   GPR_ASSERT(!reserved);
-  return grpc_channel_create_call_internal(
-      channel, parent_call, propagation_mask, completion_queue, NULL,
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_call *call = grpc_channel_create_call_internal(
+      &exec_ctx, channel, parent_call, propagation_mask, completion_queue, NULL,
       GRPC_MDELEM_REF(rc->path),
       rc->authority ? GRPC_MDELEM_REF(rc->authority) : NULL, deadline);
+  grpc_exec_ctx_finish(&exec_ctx);
+  return call;
 }
 
 #ifdef GRPC_STREAM_REFCOUNT_DEBUG
@@ -316,14 +327,14 @@
   while (channel->registered_calls) {
     registered_call *rc = channel->registered_calls;
     channel->registered_calls = rc->next;
-    GRPC_MDELEM_UNREF(rc->path);
+    GRPC_MDELEM_UNREF(exec_ctx, rc->path);
     if (rc->authority) {
-      GRPC_MDELEM_UNREF(rc->authority);
+      GRPC_MDELEM_UNREF(exec_ctx, rc->authority);
     }
     gpr_free(rc);
   }
   if (channel->default_authority != NULL) {
-    GRPC_MDELEM_UNREF(channel->default_authority);
+    GRPC_MDELEM_UNREF(exec_ctx, channel->default_authority);
   }
   gpr_mu_destroy(&channel->registered_call_mu);
   gpr_free(channel->target);
@@ -353,7 +364,8 @@
   return channel->compression_options;
 }
 
-grpc_mdelem *grpc_channel_get_reffed_status_elem(grpc_channel *channel, int i) {
+grpc_mdelem *grpc_channel_get_reffed_status_elem(grpc_exec_ctx *exec_ctx,
+                                                 grpc_channel *channel, int i) {
   char tmp[GPR_LTOA_MIN_BUFSIZE];
   switch (i) {
     case 0:
@@ -364,6 +376,6 @@
       return GRPC_MDELEM_GRPC_STATUS_2;
   }
   gpr_ltoa(i, tmp);
-  return grpc_mdelem_from_metadata_strings(GRPC_MDSTR_GRPC_STATUS,
+  return grpc_mdelem_from_metadata_strings(exec_ctx, GRPC_MDSTR_GRPC_STATUS,
                                            grpc_mdstr_from_string(tmp));
 }
diff --git a/src/core/lib/surface/channel.h b/src/core/lib/surface/channel.h
index 23cc865..2ebadb7 100644
--- a/src/core/lib/surface/channel.h
+++ b/src/core/lib/surface/channel.h
@@ -51,9 +51,10 @@
     properties from the server call to this new client call, depending on the
     value of \a propagation_mask (see propagation_bits.h for possible values) */
 grpc_call *grpc_channel_create_pollset_set_call(
-    grpc_channel *channel, grpc_call *parent_call, uint32_t propagation_mask,
-    grpc_pollset_set *pollset_set, const char *method, const char *host,
-    gpr_timespec deadline, void *reserved);
+    grpc_exec_ctx *exec_ctx, grpc_channel *channel, grpc_call *parent_call,
+    uint32_t propagation_mask, grpc_pollset_set *pollset_set,
+    const char *method, const char *host, gpr_timespec deadline,
+    void *reserved);
 
 /** Get a (borrowed) pointer to this channels underlying channel stack */
 grpc_channel_stack *grpc_channel_get_channel_stack(grpc_channel *channel);
@@ -62,7 +63,8 @@
     status_code.
 
     The returned elem is owned by the caller. */
-grpc_mdelem *grpc_channel_get_reffed_status_elem(grpc_channel *channel,
+grpc_mdelem *grpc_channel_get_reffed_status_elem(grpc_exec_ctx *exec_ctx,
+                                                 grpc_channel *channel,
                                                  int status_code);
 
 #ifdef GRPC_STREAM_REFCOUNT_DEBUG
diff --git a/src/core/lib/surface/init.c b/src/core/lib/surface/init.c
index 7903f57..8c82f38 100644
--- a/src/core/lib/surface/init.c
+++ b/src/core/lib/surface/init.c
@@ -221,6 +221,7 @@
 void grpc_shutdown(void) {
   int i;
   GRPC_API_TRACE("grpc_shutdown(void)", 0, ());
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   gpr_mu_lock(&g_init_mu);
   if (--g_initializations == 0) {
     grpc_executor_shutdown();
@@ -233,9 +234,10 @@
         g_all_of_the_plugins[i].destroy();
       }
     }
-    grpc_mdctx_global_shutdown();
+    grpc_mdctx_global_shutdown(&exec_ctx);
   }
   gpr_mu_unlock(&g_init_mu);
+  grpc_exec_ctx_finish(&exec_ctx);
 }
 
 int grpc_is_initialized(void) {
diff --git a/src/core/lib/surface/lame_client.c b/src/core/lib/surface/lame_client.c
index d32c884..1b57c5c 100644
--- a/src/core/lib/surface/lame_client.c
+++ b/src/core/lib/surface/lame_client.c
@@ -55,14 +55,15 @@
   const char *error_message;
 } channel_data;
 
-static void fill_metadata(grpc_call_element *elem, grpc_metadata_batch *mdb) {
+static void fill_metadata(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                          grpc_metadata_batch *mdb) {
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
   char tmp[GPR_LTOA_MIN_BUFSIZE];
   gpr_ltoa(chand->error_code, tmp);
-  calld->status.md = grpc_mdelem_from_strings("grpc-status", tmp);
+  calld->status.md = grpc_mdelem_from_strings(exec_ctx, "grpc-status", tmp);
   calld->details.md =
-      grpc_mdelem_from_strings("grpc-message", chand->error_message);
+      grpc_mdelem_from_strings(exec_ctx, "grpc-message", chand->error_message);
   calld->status.prev = calld->details.next = NULL;
   calld->status.next = &calld->details;
   calld->details.prev = &calld->status;
@@ -76,9 +77,9 @@
                                            grpc_transport_stream_op *op) {
   GRPC_CALL_LOG_OP(GPR_INFO, elem, op);
   if (op->recv_initial_metadata != NULL) {
-    fill_metadata(elem, op->recv_initial_metadata);
+    fill_metadata(exec_ctx, elem, op->recv_initial_metadata);
   } else if (op->recv_trailing_metadata != NULL) {
-    fill_metadata(elem, op->recv_trailing_metadata);
+    fill_metadata(exec_ctx, elem, op->recv_trailing_metadata);
   }
   grpc_transport_stream_op_finish_with_failure(
       exec_ctx, op, GRPC_ERROR_CREATE("lame client channel"));
diff --git a/src/core/lib/surface/server.c b/src/core/lib/surface/server.c
index 798f582..6d9d3a9 100644
--- a/src/core/lib/surface/server.c
+++ b/src/core/lib/surface/server.c
@@ -45,6 +45,7 @@
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/connected_channel.h"
 #include "src/core/lib/iomgr/iomgr.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/support/stack_lockfree.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/surface/api_trace.h"
@@ -270,7 +271,7 @@
 static void shutdown_cleanup(grpc_exec_ctx *exec_ctx, void *arg,
                              grpc_error *error) {
   struct shutdown_cleanup_args *a = arg;
-  grpc_slice_unref(a->slice);
+  grpc_slice_unref_internal(exec_ctx, a->slice);
   gpr_free(a);
 }
 
@@ -378,7 +379,7 @@
 static void server_delete(grpc_exec_ctx *exec_ctx, grpc_server *server) {
   registered_method *rm;
   size_t i;
-  grpc_channel_args_destroy(server->channel_args);
+  grpc_channel_args_destroy(exec_ctx, server->channel_args);
   gpr_mu_destroy(&server->mu_global);
   gpr_mu_destroy(&server->mu_call);
   while ((rm = server->registered_methods) != NULL) {
@@ -763,7 +764,8 @@
   gpr_timespec op_deadline;
 
   GRPC_ERROR_REF(error);
-  grpc_metadata_batch_filter(calld->recv_initial_metadata, server_filter, elem);
+  grpc_metadata_batch_filter(exec_ctx, calld->recv_initial_metadata,
+                             server_filter, elem);
   op_deadline = calld->recv_initial_metadata->deadline;
   if (0 != gpr_time_cmp(op_deadline, gpr_inf_future(op_deadline.clock_type))) {
     calld->deadline = op_deadline;
@@ -837,7 +839,7 @@
   args.server_transport_data = transport_server_data;
   args.send_deadline = gpr_inf_future(GPR_CLOCK_MONOTONIC);
   grpc_call *call;
-  grpc_error *error = grpc_call_create(&args, &call);
+  grpc_error *error = grpc_call_create(exec_ctx, &args, &call);
   grpc_call_element *elem =
       grpc_call_stack_element(grpc_call_get_call_stack(call), 0);
   if (error != GRPC_ERROR_NONE) {
@@ -901,10 +903,10 @@
   GPR_ASSERT(calld->state != PENDING);
 
   if (calld->host) {
-    GRPC_MDSTR_UNREF(calld->host);
+    GRPC_MDSTR_UNREF(exec_ctx, calld->host);
   }
   if (calld->path) {
-    GRPC_MDSTR_UNREF(calld->path);
+    GRPC_MDSTR_UNREF(exec_ctx, calld->path);
   }
   grpc_metadata_array_destroy(&calld->initial_metadata);
 
@@ -935,10 +937,10 @@
   if (chand->registered_methods) {
     for (i = 0; i < chand->registered_method_slots; i++) {
       if (chand->registered_methods[i].method) {
-        GRPC_MDSTR_UNREF(chand->registered_methods[i].method);
+        GRPC_MDSTR_UNREF(exec_ctx, chand->registered_methods[i].method);
       }
       if (chand->registered_methods[i].host) {
-        GRPC_MDSTR_UNREF(chand->registered_methods[i].host);
+        GRPC_MDSTR_UNREF(exec_ctx, chand->registered_methods[i].host);
       }
     }
     gpr_free(chand->registered_methods);
diff --git a/src/core/lib/transport/byte_stream.c b/src/core/lib/transport/byte_stream.c
index 2f1d7b7..4d42061 100644
--- a/src/core/lib/transport/byte_stream.c
+++ b/src/core/lib/transport/byte_stream.c
@@ -37,6 +37,8 @@
 
 #include <grpc/support/log.h>
 
+#include "src/core/lib/slice/slice_internal.h"
+
 int grpc_byte_stream_next(grpc_exec_ctx *exec_ctx,
                           grpc_byte_stream *byte_stream, grpc_slice *slice,
                           size_t max_size_hint, grpc_closure *on_complete) {
@@ -57,7 +59,8 @@
                                     grpc_closure *on_complete) {
   grpc_slice_buffer_stream *stream = (grpc_slice_buffer_stream *)byte_stream;
   GPR_ASSERT(stream->cursor < stream->backing_buffer->count);
-  *slice = grpc_slice_ref(stream->backing_buffer->slices[stream->cursor]);
+  *slice =
+      grpc_slice_ref_internal(stream->backing_buffer->slices[stream->cursor]);
   stream->cursor++;
   return 1;
 }
diff --git a/src/core/lib/transport/mdstr_hash_table.c b/src/core/lib/transport/mdstr_hash_table.c
index 8e914c4..a3f6bde 100644
--- a/src/core/lib/transport/mdstr_hash_table.c
+++ b/src/core/lib/transport/mdstr_hash_table.c
@@ -96,13 +96,14 @@
   return table;
 }
 
-int grpc_mdstr_hash_table_unref(grpc_mdstr_hash_table* table) {
+int grpc_mdstr_hash_table_unref(grpc_exec_ctx* exec_ctx,
+                                grpc_mdstr_hash_table* table) {
   if (table != NULL && gpr_unref(&table->refs)) {
     for (size_t i = 0; i < table->size; ++i) {
       grpc_mdstr_hash_table_entry* entry = &table->entries[i];
       if (entry->key != NULL) {
-        GRPC_MDSTR_UNREF(entry->key);
-        entry->vtable->destroy_value(entry->value);
+        GRPC_MDSTR_UNREF(exec_ctx, entry->key);
+        entry->vtable->destroy_value(exec_ctx, entry->value);
       }
     }
     gpr_free(table->entries);
diff --git a/src/core/lib/transport/mdstr_hash_table.h b/src/core/lib/transport/mdstr_hash_table.h
index bceb4df..45e5720 100644
--- a/src/core/lib/transport/mdstr_hash_table.h
+++ b/src/core/lib/transport/mdstr_hash_table.h
@@ -49,7 +49,7 @@
 typedef struct grpc_mdstr_hash_table grpc_mdstr_hash_table;
 
 typedef struct grpc_mdstr_hash_table_vtable {
-  void (*destroy_value)(void* value);
+  void (*destroy_value)(grpc_exec_ctx* exec_ctx, void* value);
   void* (*copy_value)(void* value);
   int (*compare_value)(void* value1, void* value2);
 } grpc_mdstr_hash_table_vtable;
@@ -68,7 +68,8 @@
 
 grpc_mdstr_hash_table* grpc_mdstr_hash_table_ref(grpc_mdstr_hash_table* table);
 /** Returns 1 when \a table is destroyed. */
-int grpc_mdstr_hash_table_unref(grpc_mdstr_hash_table* table);
+int grpc_mdstr_hash_table_unref(grpc_exec_ctx* exec_ctx,
+                                grpc_mdstr_hash_table* table);
 
 /** Returns the number of entries in \a table. */
 size_t grpc_mdstr_hash_table_num_entries(const grpc_mdstr_hash_table* table);
diff --git a/src/core/lib/transport/metadata.c b/src/core/lib/transport/metadata.c
index a1748c0..ef5fd32 100644
--- a/src/core/lib/transport/metadata.c
+++ b/src/core/lib/transport/metadata.c
@@ -47,6 +47,7 @@
 
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/support/murmur_hash.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/transport/static_metadata.h"
@@ -153,7 +154,7 @@
 static strtab_shard g_strtab_shard[STRTAB_SHARD_COUNT];
 static mdtab_shard g_mdtab_shard[MDTAB_SHARD_COUNT];
 
-static void gc_mdtab(mdtab_shard *shard);
+static void gc_mdtab(grpc_exec_ctx *exec_ctx, mdtab_shard *shard);
 
 void grpc_test_only_set_metadata_hash_seed(uint32_t seed) {
   g_hash_seed = seed;
@@ -227,12 +228,12 @@
   }
 }
 
-void grpc_mdctx_global_shutdown(void) {
+void grpc_mdctx_global_shutdown(grpc_exec_ctx *exec_ctx) {
   size_t i;
   for (i = 0; i < MDTAB_SHARD_COUNT; i++) {
     mdtab_shard *shard = &g_mdtab_shard[i];
     gpr_mu_destroy(&shard->mu);
-    gc_mdtab(shard);
+    gc_mdtab(exec_ctx, shard);
     /* TODO(ctiller): GPR_ASSERT(shard->count == 0); */
     if (shard->count != 0) {
       gpr_log(GPR_DEBUG, "WARNING: %" PRIuPTR " metadata elements were leaked",
@@ -316,12 +317,13 @@
   GPR_TIMER_END("grow_strtab", 0);
 }
 
-static void internal_destroy_string(strtab_shard *shard, internal_string *is) {
+static void internal_destroy_string(grpc_exec_ctx *exec_ctx,
+                                    strtab_shard *shard, internal_string *is) {
   internal_string **prev_next;
   internal_string *cur;
   GPR_TIMER_BEGIN("internal_destroy_string", 0);
   if (is->has_base64_and_huffman_encoded) {
-    grpc_slice_unref(is->base64_and_huffman);
+    grpc_slice_unref_internal(exec_ctx, is->base64_and_huffman);
   }
   for (prev_next = &shard->strs[TABLE_IDX(is->hash, LOG2_STRTAB_SHARD_COUNT,
                                           shard->capacity)],
@@ -340,20 +342,20 @@
   GRPC_MDSTR_REF((grpc_mdstr *)(is));
 }
 
-static void slice_unref(void *p) {
+static void slice_unref(grpc_exec_ctx *exec_ctx, void *p) {
   internal_string *is =
       (internal_string *)((char *)p - offsetof(internal_string, refcount));
-  GRPC_MDSTR_UNREF((grpc_mdstr *)(is));
+  GRPC_MDSTR_UNREF(exec_ctx, (grpc_mdstr *)(is));
 }
 
 grpc_mdstr *grpc_mdstr_from_string(const char *str) {
   return grpc_mdstr_from_buffer((const uint8_t *)str, strlen(str));
 }
 
-grpc_mdstr *grpc_mdstr_from_slice(grpc_slice slice) {
+grpc_mdstr *grpc_mdstr_from_slice(grpc_exec_ctx *exec_ctx, grpc_slice slice) {
   grpc_mdstr *result = grpc_mdstr_from_buffer(GRPC_SLICE_START_PTR(slice),
                                               GRPC_SLICE_LENGTH(slice));
-  grpc_slice_unref(slice);
+  grpc_slice_unref_internal(exec_ctx, slice);
   return result;
 }
 
@@ -444,7 +446,7 @@
   return (grpc_mdstr *)s;
 }
 
-static void gc_mdtab(mdtab_shard *shard) {
+static void gc_mdtab(grpc_exec_ctx *exec_ctx, mdtab_shard *shard) {
   size_t i;
   internal_metadata **prev_next;
   internal_metadata *md, *next;
@@ -457,8 +459,8 @@
       void *user_data = (void *)gpr_atm_no_barrier_load(&md->user_data);
       next = md->bucket_next;
       if (gpr_atm_acq_load(&md->refcnt) == 0) {
-        GRPC_MDSTR_UNREF((grpc_mdstr *)md->key);
-        GRPC_MDSTR_UNREF((grpc_mdstr *)md->value);
+        GRPC_MDSTR_UNREF(exec_ctx, (grpc_mdstr *)md->key);
+        GRPC_MDSTR_UNREF(exec_ctx, (grpc_mdstr *)md->value);
         if (md->user_data) {
           ((destroy_user_data_func)gpr_atm_no_barrier_load(
               &md->destroy_user_data))(user_data);
@@ -506,16 +508,17 @@
   GPR_TIMER_END("grow_mdtab", 0);
 }
 
-static void rehash_mdtab(mdtab_shard *shard) {
+static void rehash_mdtab(grpc_exec_ctx *exec_ctx, mdtab_shard *shard) {
   if (gpr_atm_no_barrier_load(&shard->free_estimate) >
       (gpr_atm)(shard->capacity / 4)) {
-    gc_mdtab(shard);
+    gc_mdtab(exec_ctx, shard);
   } else {
     grow_mdtab(shard);
   }
 }
 
-grpc_mdelem *grpc_mdelem_from_metadata_strings(grpc_mdstr *mkey,
+grpc_mdelem *grpc_mdelem_from_metadata_strings(grpc_exec_ctx *exec_ctx,
+                                               grpc_mdstr *mkey,
                                                grpc_mdstr *mvalue) {
   internal_string *key = (internal_string *)mkey;
   internal_string *value = (internal_string *)mvalue;
@@ -547,8 +550,8 @@
   for (md = shard->elems[idx]; md; md = md->bucket_next) {
     if (md->key == key && md->value == value) {
       REF_MD_LOCKED(shard, md);
-      GRPC_MDSTR_UNREF((grpc_mdstr *)key);
-      GRPC_MDSTR_UNREF((grpc_mdstr *)value);
+      GRPC_MDSTR_UNREF(exec_ctx, (grpc_mdstr *)key);
+      GRPC_MDSTR_UNREF(exec_ctx, (grpc_mdstr *)value);
       gpr_mu_unlock(&shard->mu);
       GPR_TIMER_END("grpc_mdelem_from_metadata_strings", 0);
       return (grpc_mdelem *)md;
@@ -574,7 +577,7 @@
   shard->count++;
 
   if (shard->count > shard->capacity * 2) {
-    rehash_mdtab(shard);
+    rehash_mdtab(exec_ctx, shard);
   }
 
   gpr_mu_unlock(&shard->mu);
@@ -584,21 +587,26 @@
   return (grpc_mdelem *)md;
 }
 
-grpc_mdelem *grpc_mdelem_from_strings(const char *key, const char *value) {
-  return grpc_mdelem_from_metadata_strings(grpc_mdstr_from_string(key),
-                                           grpc_mdstr_from_string(value));
+grpc_mdelem *grpc_mdelem_from_strings(grpc_exec_ctx *exec_ctx, const char *key,
+                                      const char *value) {
+  return grpc_mdelem_from_metadata_strings(
+      exec_ctx, grpc_mdstr_from_string(key), grpc_mdstr_from_string(value));
 }
 
-grpc_mdelem *grpc_mdelem_from_slices(grpc_slice key, grpc_slice value) {
-  return grpc_mdelem_from_metadata_strings(grpc_mdstr_from_slice(key),
-                                           grpc_mdstr_from_slice(value));
+grpc_mdelem *grpc_mdelem_from_slices(grpc_exec_ctx *exec_ctx, grpc_slice key,
+                                     grpc_slice value) {
+  return grpc_mdelem_from_metadata_strings(
+      exec_ctx, grpc_mdstr_from_slice(exec_ctx, key),
+      grpc_mdstr_from_slice(exec_ctx, value));
 }
 
-grpc_mdelem *grpc_mdelem_from_string_and_buffer(const char *key,
+grpc_mdelem *grpc_mdelem_from_string_and_buffer(grpc_exec_ctx *exec_ctx,
+                                                const char *key,
                                                 const uint8_t *value,
                                                 size_t value_length) {
   return grpc_mdelem_from_metadata_strings(
-      grpc_mdstr_from_string(key), grpc_mdstr_from_buffer(value, value_length));
+      exec_ctx, grpc_mdstr_from_string(key),
+      grpc_mdstr_from_buffer(value, value_length));
 }
 
 static size_t get_base64_encoded_size(size_t raw_length) {
@@ -654,7 +662,7 @@
   return gmd;
 }
 
-void grpc_mdelem_unref(grpc_mdelem *gmd DEBUG_ARGS) {
+void grpc_mdelem_unref(grpc_exec_ctx *exec_ctx, grpc_mdelem *gmd DEBUG_ARGS) {
   internal_metadata *md = (internal_metadata *)gmd;
   if (!md) return;
   if (is_mdelem_static(gmd)) return;
@@ -691,7 +699,7 @@
   return gs;
 }
 
-void grpc_mdstr_unref(grpc_mdstr *gs DEBUG_ARGS) {
+void grpc_mdstr_unref(grpc_exec_ctx *exec_ctx, grpc_mdstr *gs DEBUG_ARGS) {
   internal_string *s = (internal_string *)gs;
   if (is_mdstr_static(gs)) return;
   if (1 == gpr_atm_full_fetch_add(&s->refcnt, -1)) {
@@ -699,7 +707,7 @@
         &g_strtab_shard[SHARD_IDX(s->hash, LOG2_STRTAB_SHARD_COUNT)];
     gpr_mu_lock(&shard->mu);
     GPR_ASSERT(0 == gpr_atm_no_barrier_load(&s->refcnt));
-    internal_destroy_string(shard, s);
+    internal_destroy_string(exec_ctx, shard, s);
     gpr_mu_unlock(&shard->mu);
   }
 }
diff --git a/src/core/lib/transport/metadata.h b/src/core/lib/transport/metadata.h
index 8dcfbb9..cf77753 100644
--- a/src/core/lib/transport/metadata.h
+++ b/src/core/lib/transport/metadata.h
@@ -96,7 +96,7 @@
    clients may have handy */
 grpc_mdstr *grpc_mdstr_from_string(const char *str);
 /* Unrefs the slice. */
-grpc_mdstr *grpc_mdstr_from_slice(grpc_slice slice);
+grpc_mdstr *grpc_mdstr_from_slice(grpc_exec_ctx *exec_ctx, grpc_slice slice);
 grpc_mdstr *grpc_mdstr_from_buffer(const uint8_t *str, size_t length);
 
 /* Returns a borrowed slice from the mdstr with its contents base64 encoded
@@ -105,12 +105,16 @@
 
 /* Constructors for grpc_mdelem instances; take a variety of data types that
    clients may have handy */
-grpc_mdelem *grpc_mdelem_from_metadata_strings(grpc_mdstr *key,
+grpc_mdelem *grpc_mdelem_from_metadata_strings(grpc_exec_ctx *exec_ctx,
+                                               grpc_mdstr *key,
                                                grpc_mdstr *value);
-grpc_mdelem *grpc_mdelem_from_strings(const char *key, const char *value);
+grpc_mdelem *grpc_mdelem_from_strings(grpc_exec_ctx *exec_ctx, const char *key,
+                                      const char *value);
 /* Unrefs the slices. */
-grpc_mdelem *grpc_mdelem_from_slices(grpc_slice key, grpc_slice value);
-grpc_mdelem *grpc_mdelem_from_string_and_buffer(const char *key,
+grpc_mdelem *grpc_mdelem_from_slices(grpc_exec_ctx *exec_ctx, grpc_slice key,
+                                     grpc_slice value);
+grpc_mdelem *grpc_mdelem_from_string_and_buffer(grpc_exec_ctx *exec_ctx,
+                                                const char *key,
                                                 const uint8_t *value,
                                                 size_t value_length);
 
@@ -127,22 +131,26 @@
 //#define GRPC_METADATA_REFCOUNT_DEBUG
 #ifdef GRPC_METADATA_REFCOUNT_DEBUG
 #define GRPC_MDSTR_REF(s) grpc_mdstr_ref((s), __FILE__, __LINE__)
-#define GRPC_MDSTR_UNREF(s) grpc_mdstr_unref((s), __FILE__, __LINE__)
+#define GRPC_MDSTR_UNREF(exec_ctx, s) \
+  grpc_mdstr_unref((exec_ctx), (s), __FILE__, __LINE__)
 #define GRPC_MDELEM_REF(s) grpc_mdelem_ref((s), __FILE__, __LINE__)
-#define GRPC_MDELEM_UNREF(s) grpc_mdelem_unref((s), __FILE__, __LINE__)
+#define GRPC_MDELEM_UNREF(exec_ctx, s) \
+  grpc_mdelem_unref((exec_ctx), (s), __FILE__, __LINE__)
 grpc_mdstr *grpc_mdstr_ref(grpc_mdstr *s, const char *file, int line);
-void grpc_mdstr_unref(grpc_mdstr *s, const char *file, int line);
+void grpc_mdstr_unref(grpc_exec_ctx *exec_ctx, grpc_mdstr *s, const char *file,
+                      int line);
 grpc_mdelem *grpc_mdelem_ref(grpc_mdelem *md, const char *file, int line);
-void grpc_mdelem_unref(grpc_mdelem *md, const char *file, int line);
+void grpc_mdelem_unref(grpc_exec_ctx *exec_ctx, grpc_mdelem *md,
+                       const char *file, int line);
 #else
 #define GRPC_MDSTR_REF(s) grpc_mdstr_ref((s))
-#define GRPC_MDSTR_UNREF(s) grpc_mdstr_unref((s))
+#define GRPC_MDSTR_UNREF(exec_ctx, s) grpc_mdstr_unref((exec_ctx), (s))
 #define GRPC_MDELEM_REF(s) grpc_mdelem_ref((s))
-#define GRPC_MDELEM_UNREF(s) grpc_mdelem_unref((s))
+#define GRPC_MDELEM_UNREF(exec_ctx, s) grpc_mdelem_unref((exec_ctx), (s))
 grpc_mdstr *grpc_mdstr_ref(grpc_mdstr *s);
-void grpc_mdstr_unref(grpc_mdstr *s);
+void grpc_mdstr_unref(grpc_exec_ctx *exec_ctx, grpc_mdstr *s);
 grpc_mdelem *grpc_mdelem_ref(grpc_mdelem *md);
-void grpc_mdelem_unref(grpc_mdelem *md);
+void grpc_mdelem_unref(grpc_exec_ctx *exec_ctx, grpc_mdelem *md);
 #endif
 
 /* Recover a char* from a grpc_mdstr. The returned string is null terminated.
@@ -162,7 +170,7 @@
 #define GRPC_MDSTR_KV_HASH(k_hash, v_hash) (GPR_ROTL((k_hash), 2) ^ (v_hash))
 
 void grpc_mdctx_global_init(void);
-void grpc_mdctx_global_shutdown(void);
+void grpc_mdctx_global_shutdown(grpc_exec_ctx *exec_ctx);
 
 /* Implementation provided by chttp2_transport */
 extern grpc_slice (*grpc_chttp2_base64_encode_and_huffman_compress)(
diff --git a/src/core/lib/transport/metadata_batch.c b/src/core/lib/transport/metadata_batch.c
index 84b5a74..4430224 100644
--- a/src/core/lib/transport/metadata_batch.c
+++ b/src/core/lib/transport/metadata_batch.c
@@ -72,10 +72,11 @@
   batch->deadline = gpr_inf_future(GPR_CLOCK_REALTIME);
 }
 
-void grpc_metadata_batch_destroy(grpc_metadata_batch *batch) {
+void grpc_metadata_batch_destroy(grpc_exec_ctx *exec_ctx,
+                                 grpc_metadata_batch *batch) {
   grpc_linked_mdelem *l;
   for (l = batch->list.head; l; l = l->next) {
-    GRPC_MDELEM_UNREF(l->md);
+    GRPC_MDELEM_UNREF(exec_ctx, l->md);
   }
 }
 
@@ -140,7 +141,8 @@
   memset(src, 0, sizeof(grpc_metadata_batch));
 }
 
-void grpc_metadata_batch_filter(grpc_metadata_batch *batch,
+void grpc_metadata_batch_filter(grpc_exec_ctx *exec_ctx,
+                                grpc_metadata_batch *batch,
                                 grpc_mdelem *(*filter)(void *user_data,
                                                        grpc_mdelem *elem),
                                 void *user_data) {
@@ -168,9 +170,9 @@
         batch->list.tail = l->prev;
       }
       assert_valid_list(&batch->list);
-      GRPC_MDELEM_UNREF(l->md);
+      GRPC_MDELEM_UNREF(exec_ctx, l->md);
     } else if (filt != orig) {
-      GRPC_MDELEM_UNREF(orig);
+      GRPC_MDELEM_UNREF(exec_ctx, orig);
       l->md = filt;
     }
   }
@@ -183,9 +185,10 @@
   return NULL;
 }
 
-void grpc_metadata_batch_clear(grpc_metadata_batch *batch) {
+void grpc_metadata_batch_clear(grpc_exec_ctx *exec_ctx,
+                               grpc_metadata_batch *batch) {
   batch->deadline = gpr_inf_future(GPR_CLOCK_REALTIME);
-  grpc_metadata_batch_filter(batch, no_metadata_for_you, NULL);
+  grpc_metadata_batch_filter(exec_ctx, batch, no_metadata_for_you, NULL);
 }
 
 bool grpc_metadata_batch_is_empty(grpc_metadata_batch *batch) {
diff --git a/src/core/lib/transport/metadata_batch.h b/src/core/lib/transport/metadata_batch.h
index 7a9ccb4..862c21b 100644
--- a/src/core/lib/transport/metadata_batch.h
+++ b/src/core/lib/transport/metadata_batch.h
@@ -68,8 +68,10 @@
 } grpc_metadata_batch;
 
 void grpc_metadata_batch_init(grpc_metadata_batch *batch);
-void grpc_metadata_batch_destroy(grpc_metadata_batch *batch);
-void grpc_metadata_batch_clear(grpc_metadata_batch *batch);
+void grpc_metadata_batch_destroy(grpc_exec_ctx *exec_ctx,
+                                 grpc_metadata_batch *batch);
+void grpc_metadata_batch_clear(grpc_exec_ctx *exec_ctx,
+                               grpc_metadata_batch *batch);
 bool grpc_metadata_batch_is_empty(grpc_metadata_batch *batch);
 
 /* Returns the transport size of the batch. */
@@ -118,7 +120,8 @@
     The return value from \a filter will be substituted for the
     grpc_mdelem passed to \a filter. If \a filter returns NULL,
     the element will be moved to the garbage list. */
-void grpc_metadata_batch_filter(grpc_metadata_batch *batch,
+void grpc_metadata_batch_filter(grpc_exec_ctx *exec_ctx,
+                                grpc_metadata_batch *batch,
                                 grpc_mdelem *(*filter)(void *user_data,
                                                        grpc_mdelem *elem),
                                 void *user_data);
diff --git a/src/core/lib/transport/method_config.c b/src/core/lib/transport/method_config.c
index 57d9770..25fb54b 100644
--- a/src/core/lib/transport/method_config.c
+++ b/src/core/lib/transport/method_config.c
@@ -63,7 +63,9 @@
   return 0;
 }
 
-static grpc_mdstr_hash_table_vtable bool_vtable = {gpr_free, bool_copy,
+static void free_mem(grpc_exec_ctx* exec_ctx, void* p) { gpr_free(p); }
+
+static grpc_mdstr_hash_table_vtable bool_vtable = {free_mem, bool_copy,
                                                    bool_cmp};
 
 // timespec vtable
@@ -79,7 +81,7 @@
   return gpr_time_cmp(*(gpr_timespec*)v1, *(gpr_timespec*)v2);
 }
 
-static grpc_mdstr_hash_table_vtable timespec_vtable = {gpr_free, timespec_copy,
+static grpc_mdstr_hash_table_vtable timespec_vtable = {free_mem, timespec_copy,
                                                        timespec_cmp};
 
 // int32 vtable
@@ -99,7 +101,7 @@
   return 0;
 }
 
-static grpc_mdstr_hash_table_vtable int32_vtable = {gpr_free, int32_copy,
+static grpc_mdstr_hash_table_vtable int32_vtable = {free_mem, int32_copy,
                                                     int32_cmp};
 
 // Hash table keys.
@@ -166,12 +168,13 @@
   return method_config;
 }
 
-void grpc_method_config_unref(grpc_method_config* method_config) {
-  if (grpc_mdstr_hash_table_unref(method_config->table)) {
-    GRPC_MDSTR_UNREF(method_config->wait_for_ready_key);
-    GRPC_MDSTR_UNREF(method_config->timeout_key);
-    GRPC_MDSTR_UNREF(method_config->max_request_message_bytes_key);
-    GRPC_MDSTR_UNREF(method_config->max_response_message_bytes_key);
+void grpc_method_config_unref(grpc_exec_ctx* exec_ctx,
+                              grpc_method_config* method_config) {
+  if (grpc_mdstr_hash_table_unref(exec_ctx, method_config->table)) {
+    GRPC_MDSTR_UNREF(exec_ctx, method_config->wait_for_ready_key);
+    GRPC_MDSTR_UNREF(exec_ctx, method_config->timeout_key);
+    GRPC_MDSTR_UNREF(exec_ctx, method_config->max_request_message_bytes_key);
+    GRPC_MDSTR_UNREF(exec_ctx, method_config->max_response_message_bytes_key);
     gpr_free(method_config);
   }
 }
@@ -210,8 +213,8 @@
 // grpc_method_config_table
 //
 
-static void method_config_unref(void* valuep) {
-  grpc_method_config_unref(valuep);
+static void method_config_unref(grpc_exec_ctx* exec_ctx, void* valuep) {
+  grpc_method_config_unref(exec_ctx, valuep);
 }
 
 static void* method_config_ref(void* valuep) {
@@ -245,8 +248,9 @@
   return grpc_mdstr_hash_table_ref(table);
 }
 
-void grpc_method_config_table_unref(grpc_method_config_table* table) {
-  grpc_mdstr_hash_table_unref(table);
+void grpc_method_config_table_unref(grpc_exec_ctx* exec_ctx,
+                                    grpc_method_config_table* table) {
+  grpc_mdstr_hash_table_unref(exec_ctx, table);
 }
 
 int grpc_method_config_table_cmp(const grpc_method_config_table* table1,
@@ -254,7 +258,8 @@
   return grpc_mdstr_hash_table_cmp(table1, table2);
 }
 
-void* grpc_method_config_table_get(const grpc_mdstr_hash_table* table,
+void* grpc_method_config_table_get(grpc_exec_ctx* exec_ctx,
+                                   const grpc_mdstr_hash_table* table,
                                    const grpc_mdstr* path) {
   void* value = grpc_mdstr_hash_table_get(table, path);
   // If we didn't find a match for the path, try looking for a wildcard
@@ -270,14 +275,16 @@
     grpc_mdstr* wildcard_path = grpc_mdstr_from_string(buf);
     gpr_free(buf);
     value = grpc_mdstr_hash_table_get(table, wildcard_path);
-    GRPC_MDSTR_UNREF(wildcard_path);
+    GRPC_MDSTR_UNREF(exec_ctx, wildcard_path);
   }
   return value;
 }
 
 static void* copy_arg(void* p) { return grpc_method_config_table_ref(p); }
 
-static void destroy_arg(void* p) { grpc_method_config_table_unref(p); }
+static void destroy_arg(grpc_exec_ctx* exec_ctx, void* p) {
+  grpc_method_config_table_unref(exec_ctx, p);
+}
 
 static int cmp_arg(void* p1, void* p2) {
   return grpc_method_config_table_cmp(p1, p2);
@@ -315,7 +322,7 @@
 }
 
 grpc_mdstr_hash_table* grpc_method_config_table_convert(
-    const grpc_method_config_table* table,
+    grpc_exec_ctx* exec_ctx, const grpc_method_config_table* table,
     void* (*convert_value)(const grpc_method_config* method_config),
     const grpc_mdstr_hash_table_vtable* vtable) {
   // Create an array of the entries in the table with converted values.
@@ -331,8 +338,8 @@
       grpc_mdstr_hash_table_create(state.num_entries, state.entries);
   // Clean up the array.
   for (size_t i = 0; i < state.num_entries; ++i) {
-    GRPC_MDSTR_UNREF(state.entries[i].key);
-    vtable->destroy_value(state.entries[i].value);
+    GRPC_MDSTR_UNREF(exec_ctx, state.entries[i].key);
+    vtable->destroy_value(exec_ctx, state.entries[i].value);
   }
   gpr_free(state.entries);
   // Return the new table.
diff --git a/src/core/lib/transport/method_config.h b/src/core/lib/transport/method_config.h
index 58fedd9..d17a493 100644
--- a/src/core/lib/transport/method_config.h
+++ b/src/core/lib/transport/method_config.h
@@ -60,7 +60,8 @@
     int32_t* max_request_message_bytes, int32_t* max_response_message_bytes);
 
 grpc_method_config* grpc_method_config_ref(grpc_method_config* method_config);
-void grpc_method_config_unref(grpc_method_config* method_config);
+void grpc_method_config_unref(grpc_exec_ctx* exec_ctx,
+                              grpc_method_config* method_config);
 
 /// Compares two grpc_method_configs.
 /// The sort order is stable but undefined.
@@ -95,7 +96,8 @@
 
 grpc_method_config_table* grpc_method_config_table_ref(
     grpc_method_config_table* table);
-void grpc_method_config_table_unref(grpc_method_config_table* table);
+void grpc_method_config_table_unref(grpc_exec_ctx* exec_ctx,
+                                    grpc_method_config_table* table);
 
 /// Compares two grpc_method_config_tables.
 /// The sort order is stable but undefined.
@@ -110,7 +112,8 @@
 /// Note: This returns a void* instead of a grpc_method_config* so that
 /// it can also be used for tables constructed via
 /// grpc_method_config_table_convert().
-void* grpc_method_config_table_get(const grpc_mdstr_hash_table* table,
+void* grpc_method_config_table_get(grpc_exec_ctx* exec_ctx,
+                                   const grpc_mdstr_hash_table* table,
                                    const grpc_mdstr* path);
 
 /// Returns a channel arg containing \a table.
@@ -129,7 +132,7 @@
 /// the grpc_method_config, and \a vtable provides the methods for
 /// operating on the struct type.
 grpc_mdstr_hash_table* grpc_method_config_table_convert(
-    const grpc_method_config_table* table,
+    grpc_exec_ctx* exec_ctx, const grpc_method_config_table* table,
     void* (*convert_value)(const grpc_method_config* method_config),
     const grpc_mdstr_hash_table_vtable* vtable);
 
diff --git a/src/core/lib/transport/transport.c b/src/core/lib/transport/transport.c
index 866cd9e..1b79520 100644
--- a/src/core/lib/transport/transport.c
+++ b/src/core/lib/transport/transport.c
@@ -40,6 +40,7 @@
 #include <grpc/support/log.h>
 #include <grpc/support/sync.h>
 
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/transport/transport_impl.h"
@@ -207,12 +208,12 @@
 }
 
 void grpc_transport_stream_op_add_cancellation_with_message(
-    grpc_transport_stream_op *op, grpc_status_code status,
-    grpc_slice *optional_message) {
+    grpc_exec_ctx *exec_ctx, grpc_transport_stream_op *op,
+    grpc_status_code status, grpc_slice *optional_message) {
   GPR_ASSERT(status != GRPC_STATUS_OK);
   if (op->cancel_error != GRPC_ERROR_NONE) {
     if (optional_message) {
-      grpc_slice_unref(*optional_message);
+      grpc_slice_unref_internal(exec_ctx, *optional_message);
     }
     return;
   }
@@ -222,7 +223,7 @@
     error = grpc_error_set_str(GRPC_ERROR_CREATE(msg),
                                GRPC_ERROR_STR_GRPC_MESSAGE, msg);
     gpr_free(msg);
-    grpc_slice_unref(*optional_message);
+    grpc_slice_unref_internal(exec_ctx, *optional_message);
   } else {
     error = GRPC_ERROR_CREATE("Call cancelled");
   }
@@ -230,14 +231,15 @@
   add_error(op, &op->cancel_error, error);
 }
 
-void grpc_transport_stream_op_add_close(grpc_transport_stream_op *op,
+void grpc_transport_stream_op_add_close(grpc_exec_ctx *exec_ctx,
+                                        grpc_transport_stream_op *op,
                                         grpc_status_code status,
                                         grpc_slice *optional_message) {
   GPR_ASSERT(status != GRPC_STATUS_OK);
   if (op->cancel_error != GRPC_ERROR_NONE ||
       op->close_error != GRPC_ERROR_NONE) {
     if (optional_message) {
-      grpc_slice_unref(*optional_message);
+      grpc_slice_unref_internal(exec_ctx, *optional_message);
     }
     return;
   }
@@ -247,7 +249,7 @@
     error = grpc_error_set_str(GRPC_ERROR_CREATE(msg),
                                GRPC_ERROR_STR_GRPC_MESSAGE, msg);
     gpr_free(msg);
-    grpc_slice_unref(*optional_message);
+    grpc_slice_unref_internal(exec_ctx, *optional_message);
   } else {
     error = GRPC_ERROR_CREATE("Call force closed");
   }
diff --git a/src/core/lib/transport/transport.h b/src/core/lib/transport/transport.h
index 8916b28..3e38d98 100644
--- a/src/core/lib/transport/transport.h
+++ b/src/core/lib/transport/transport.h
@@ -248,10 +248,11 @@
                                                grpc_status_code status);
 
 void grpc_transport_stream_op_add_cancellation_with_message(
-    grpc_transport_stream_op *op, grpc_status_code status,
-    grpc_slice *optional_message);
+    grpc_exec_ctx *exec_ctx, grpc_transport_stream_op *op,
+    grpc_status_code status, grpc_slice *optional_message);
 
-void grpc_transport_stream_op_add_close(grpc_transport_stream_op *op,
+void grpc_transport_stream_op_add_close(grpc_exec_ctx *exec_ctx,
+                                        grpc_transport_stream_op *op,
                                         grpc_status_code status,
                                         grpc_slice *optional_message);