Merge remote-tracking branch 'upstream/master' into service_config_lb_semantics

17 files changed, 253 insertions, 236 deletions

diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
index c590184a62..f980932cd5 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
@@ -1122,6 +1122,7 @@ static void lb_call_init_locked(grpc_exec_ctx *exec_ctx,
       glb_policy->base.interested_parties,
       GRPC_MDSTR_SLASH_GRPC_DOT_LB_DOT_V1_DOT_LOADBALANCER_SLASH_BALANCELOAD,
       &host, glb_policy->deadline, NULL);
+  grpc_slice_unref_internal(exec_ctx, host);
 
   grpc_metadata_array_init(&glb_policy->lb_initial_metadata_recv);
   grpc_metadata_array_init(&glb_policy->lb_trailing_metadata_recv);
@@ -1152,7 +1153,7 @@ static void lb_call_init_locked(grpc_exec_ctx *exec_ctx,
 static void lb_call_destroy_locked(grpc_exec_ctx *exec_ctx,
                                    glb_lb_policy *glb_policy) {
   GPR_ASSERT(glb_policy->lb_call != NULL);
-  grpc_call_destroy(glb_policy->lb_call);
+  grpc_call_unref(glb_policy->lb_call);
   glb_policy->lb_call = NULL;
 
   grpc_metadata_array_destroy(&glb_policy->lb_initial_metadata_recv);
@@ -1293,6 +1294,7 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
                   "Received empty server list. Picks will stay pending until a "
                   "response with > 0 servers is received");
         }
+        grpc_grpclb_destroy_serverlist(glb_policy->serverlist);
       }
     } else { /* serverlist == NULL */
       gpr_log(GPR_ERROR, "Invalid LB response received: '%s'. Ignoring.",
diff --git a/src/core/ext/filters/client_channel/subchannel.c b/src/core/ext/filters/client_channel/subchannel.c
index 362b4a4a28..967e571221 100644
--- a/src/core/ext/filters/client_channel/subchannel.c
+++ b/src/core/ext/filters/client_channel/subchannel.c
@@ -59,9 +59,9 @@
 #define INTERNAL_REF_BITS 16
 #define STRONG_REF_MASK (~(gpr_atm)((1 << INTERNAL_REF_BITS) - 1))
 
-#define GRPC_SUBCHANNEL_MIN_CONNECT_TIMEOUT_SECONDS 20
 #define GRPC_SUBCHANNEL_INITIAL_CONNECT_BACKOFF_SECONDS 1
 #define GRPC_SUBCHANNEL_RECONNECT_BACKOFF_MULTIPLIER 1.6
+#define GRPC_SUBCHANNEL_RECONNECT_MIN_BACKOFF_SECONDS 20
 #define GRPC_SUBCHANNEL_RECONNECT_MAX_BACKOFF_SECONDS 120
 #define GRPC_SUBCHANNEL_RECONNECT_JITTER 0.2
 
@@ -353,8 +353,8 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
                                "subchannel");
   int initial_backoff_ms =
       GRPC_SUBCHANNEL_INITIAL_CONNECT_BACKOFF_SECONDS * 1000;
+  int min_backoff_ms = GRPC_SUBCHANNEL_RECONNECT_MIN_BACKOFF_SECONDS * 1000;
   int max_backoff_ms = GRPC_SUBCHANNEL_RECONNECT_MAX_BACKOFF_SECONDS * 1000;
-  int min_backoff_ms = GRPC_SUBCHANNEL_MIN_CONNECT_TIMEOUT_SECONDS * 1000;
   bool fixed_reconnect_backoff = false;
   if (c->args) {
     for (size_t i = 0; i < c->args->num_args; i++) {
@@ -366,6 +366,12 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
                 &c->args->args[i],
                 (grpc_integer_options){initial_backoff_ms, 100, INT_MAX});
       } else if (0 == strcmp(c->args->args[i].key,
+                             GRPC_ARG_MIN_RECONNECT_BACKOFF_MS)) {
+        fixed_reconnect_backoff = false;
+        min_backoff_ms = grpc_channel_arg_get_integer(
+            &c->args->args[i],
+            (grpc_integer_options){min_backoff_ms, 100, INT_MAX});
+      } else if (0 == strcmp(c->args->args[i].key,
                              GRPC_ARG_MAX_RECONNECT_BACKOFF_MS)) {
         fixed_reconnect_backoff = false;
         max_backoff_ms = grpc_channel_arg_get_integer(
diff --git a/src/core/ext/filters/load_reporting/load_reporting.c b/src/core/ext/filters/load_reporting/load_reporting.c
index 3b5d2103c1..4e9d0937ae 100644
--- a/src/core/ext/filters/load_reporting/load_reporting.c
+++ b/src/core/ext/filters/load_reporting/load_reporting.c
@@ -47,23 +47,6 @@
 #include "src/core/lib/surface/call.h"
 #include "src/core/lib/surface/channel_init.h"
 
-static void destroy_lr_cost_context(void *c) {
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_load_reporting_cost_context *cost_ctx = c;
-  for (size_t i = 0; i < cost_ctx->values_count; ++i) {
-    grpc_slice_unref_internal(&exec_ctx, cost_ctx->values[i]);
-  }
-  grpc_exec_ctx_finish(&exec_ctx);
-  gpr_free(cost_ctx->values);
-  gpr_free(cost_ctx);
-}
-
-void grpc_call_set_load_reporting_cost_context(
-    grpc_call *call, grpc_load_reporting_cost_context *ctx) {
-  grpc_call_context_set(call, GRPC_CONTEXT_LR_COST, ctx,
-                        destroy_lr_cost_context);
-}
-
 static bool is_load_reporting_enabled(const grpc_channel_args *a) {
   return grpc_channel_arg_get_bool(
       grpc_channel_args_find(a, GRPC_ARG_ENABLE_LOAD_REPORTING), false);
diff --git a/src/core/ext/filters/load_reporting/load_reporting_filter.c b/src/core/ext/filters/load_reporting/load_reporting_filter.c
index 57b25d0651..75a9a56687 100644
--- a/src/core/ext/filters/load_reporting/load_reporting_filter.c
+++ b/src/core/ext/filters/load_reporting/load_reporting_filter.c
@@ -48,6 +48,8 @@
 
 typedef struct call_data {
   intptr_t id; /**< an id unique to the call */
+  bool have_trailing_md_string;
+  grpc_slice trailing_md_string;
   bool have_initial_md_string;
   grpc_slice initial_md_string;
   bool have_service_method;
@@ -140,6 +142,9 @@ static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
   if (calld->have_initial_md_string) {
     grpc_slice_unref_internal(exec_ctx, calld->initial_md_string);
   }
+  if (calld->have_trailing_md_string) {
+    grpc_slice_unref_internal(exec_ctx, calld->trailing_md_string);
+  }
   if (calld->have_service_method) {
     grpc_slice_unref_internal(exec_ctx, calld->service_method);
   }
@@ -183,6 +188,18 @@ static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
   */
 }
 
+static grpc_filtered_mdelem lr_trailing_md_filter(grpc_exec_ctx *exec_ctx,
+                                                  void *user_data,
+                                                  grpc_mdelem md) {
+  grpc_call_element *elem = user_data;
+  call_data *calld = elem->call_data;
+  if (grpc_slice_eq(GRPC_MDKEY(md), GRPC_MDSTR_LB_COST_BIN)) {
+    calld->trailing_md_string = GRPC_MDVALUE(md);
+    return GRPC_FILTERED_REMOVE();
+  }
+  return GRPC_FILTERED_MDELEM(md);
+}
+
 static void lr_start_transport_stream_op_batch(
     grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
     grpc_transport_stream_op_batch *op) {
@@ -190,13 +207,21 @@ static void lr_start_transport_stream_op_batch(
   call_data *calld = elem->call_data;
 
   if (op->recv_initial_metadata) {
+    /* substitute our callback for the higher callback */
     calld->recv_initial_metadata =
         op->payload->recv_initial_metadata.recv_initial_metadata;
-    /* substitute our callback for the higher callback */
     calld->ops_recv_initial_metadata_ready =
         op->payload->recv_initial_metadata.recv_initial_metadata_ready;
     op->payload->recv_initial_metadata.recv_initial_metadata_ready =
         &calld->on_initial_md_ready;
+  } else if (op->send_trailing_metadata) {
+    GRPC_LOG_IF_ERROR(
+        "grpc_metadata_batch_filter",
+        grpc_metadata_batch_filter(
+            exec_ctx,
+            op->payload->send_trailing_metadata.send_trailing_metadata,
+            lr_trailing_md_filter, elem,
+            "LR trailing metadata filtering error"));
   }
   grpc_call_next_op(exec_ctx, elem, op);
 
diff --git a/src/core/ext/filters/message_size/message_size_filter.c b/src/core/ext/filters/message_size/message_size_filter.c
index db0f011905..e3ffc41f90 100644
--- a/src/core/ext/filters/message_size/message_size_filter.c
+++ b/src/core/ext/filters/message_size/message_size_filter.c
@@ -130,6 +130,8 @@ static void recv_message_ready(grpc_exec_ctx* exec_ctx, void* user_data,
       GRPC_ERROR_UNREF(new_error);
     }
     gpr_free(message_string);
+  } else {
+    GRPC_ERROR_REF(error);
   }
   // Invoke the next callback.
   grpc_closure_run(exec_ctx, calld->next_recv_message_ready, error);
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.c b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
index 9269611dd9..5d74532ede 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.c
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
@@ -1679,7 +1679,7 @@ void grpc_chttp2_maybe_complete_recv_message(grpc_exec_ctx *exec_ctx,
           grpc_slice_buffer_swap(&s->unprocessed_incoming_frames_buffer,
                                  &s->frame_storage);
         }
-        error = deframe_unprocessed_incoming_frames(
+        error = grpc_deframe_unprocessed_incoming_frames(
             exec_ctx, &s->data_parser, s,
             &s->unprocessed_incoming_frames_buffer, NULL, s->recv_message);
         if (error != GRPC_ERROR_NONE) {
@@ -2150,6 +2150,7 @@ static void update_bdp(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
             (int)bdp);
   }
   push_setting(exec_ctx, t, GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE, bdp);
+  push_setting(exec_ctx, t, GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE, bdp);
 }
 
 static grpc_error *try_http_parsing(grpc_exec_ctx *exec_ctx,
@@ -2602,6 +2603,7 @@ static bool incoming_byte_stream_next(grpc_exec_ctx *exec_ctx,
       (grpc_chttp2_incoming_byte_stream *)byte_stream;
   grpc_chttp2_stream *s = bs->stream;
   if (s->unprocessed_incoming_frames_buffer.length > 0) {
+    GPR_TIMER_END("incoming_byte_stream_next", 0);
     return true;
   } else {
     gpr_ref(&bs->refs);
@@ -2627,7 +2629,7 @@ static grpc_error *incoming_byte_stream_pull(grpc_exec_ctx *exec_ctx,
   grpc_chttp2_stream *s = bs->stream;
 
   if (s->unprocessed_incoming_frames_buffer.length > 0) {
-    grpc_error *error = deframe_unprocessed_incoming_frames(
+    grpc_error *error = grpc_deframe_unprocessed_incoming_frames(
         exec_ctx, &s->data_parser, s, &s->unprocessed_incoming_frames_buffer,
         slice, NULL);
     if (error != GRPC_ERROR_NONE) {
diff --git a/src/core/ext/transport/chttp2/transport/frame_data.c b/src/core/ext/transport/chttp2/transport/frame_data.c
index 5d382d80a8..9aba3ea445 100644
--- a/src/core/ext/transport/chttp2/transport/frame_data.c
+++ b/src/core/ext/transport/chttp2/transport/frame_data.c
@@ -112,12 +112,10 @@ void grpc_chttp2_encode_data(uint32_t id, grpc_slice_buffer *inbuf,
   stats->data_bytes += write_bytes;
 }
 
-grpc_error *deframe_unprocessed_incoming_frames(grpc_exec_ctx *exec_ctx,
-                                                grpc_chttp2_data_parser *p,
-                                                grpc_chttp2_stream *s,
-                                                grpc_slice_buffer *slices,
-                                                grpc_slice *slice_out,
-                                                grpc_byte_stream **stream_out) {
+grpc_error *grpc_deframe_unprocessed_incoming_frames(
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_data_parser *p, grpc_chttp2_stream *s,
+    grpc_slice_buffer *slices, grpc_slice *slice_out,
+    grpc_byte_stream **stream_out) {
   grpc_error *error = GRPC_ERROR_NONE;
   grpc_chttp2_transport *t = s->t;
 
diff --git a/src/core/ext/transport/chttp2/transport/frame_data.h b/src/core/ext/transport/chttp2/transport/frame_data.h
index 2fb8983c38..9ed4ad0f21 100644
--- a/src/core/ext/transport/chttp2/transport/frame_data.h
+++ b/src/core/ext/transport/chttp2/transport/frame_data.h
@@ -90,11 +90,9 @@ void grpc_chttp2_encode_data(uint32_t id, grpc_slice_buffer *inbuf,
                              grpc_transport_one_way_stats *stats,
                              grpc_slice_buffer *outbuf);
 
-grpc_error *deframe_unprocessed_incoming_frames(grpc_exec_ctx *exec_ctx,
-                                                grpc_chttp2_data_parser *p,
-                                                grpc_chttp2_stream *s,
-                                                grpc_slice_buffer *slices,
-                                                grpc_slice *slice_out,
-                                                grpc_byte_stream **stream_out);
+grpc_error *grpc_deframe_unprocessed_incoming_frames(
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_data_parser *p, grpc_chttp2_stream *s,
+    grpc_slice_buffer *slices, grpc_slice *slice_out,
+    grpc_byte_stream **stream_out);
 
 #endif /* GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_FRAME_DATA_H */
diff --git a/src/core/lib/channel/context.h b/src/core/lib/channel/context.h
index 2c1174ce7a..6c931ad28a 100644
--- a/src/core/lib/channel/context.h
+++ b/src/core/lib/channel/context.h
@@ -50,9 +50,6 @@ typedef enum {
   /// Reserved for traffic_class_context.
   GRPC_CONTEXT_TRAFFIC,
 
-  /// Costs for Load Reporting.
-  GRPC_CONTEXT_LR_COST,
-
   GRPC_CONTEXT_COUNT
 } grpc_context_index;
 
diff --git a/src/core/lib/iomgr/error.c b/src/core/lib/iomgr/error.c
index fbbca6b493..5f2c989aad 100644
--- a/src/core/lib/iomgr/error.c
+++ b/src/core/lib/iomgr/error.c
@@ -217,8 +217,14 @@ static uint8_t get_placement(grpc_error **err, size_t size) {
     if ((*err)->arena_size + slots > (*err)->arena_capacity) {
       return UINT8_MAX;
     }
+#ifdef GRPC_ERROR_REFCOUNT_DEBUG
+    grpc_error *orig = *err;
+#endif
     *err = gpr_realloc(
         *err, sizeof(grpc_error) + (*err)->arena_capacity * sizeof(intptr_t));
+#ifdef GRPC_ERROR_REFCOUNT_DEBUG
+    if (*err != orig) gpr_log(GPR_DEBUG, "realloc %p -> %p", orig, *err);
+#endif
   }
   uint8_t placement = (*err)->arena_size;
   (*err)->arena_size = (uint8_t)((*err)->arena_size + slots);
@@ -313,7 +319,7 @@ static void internal_add_error(grpc_error **err, grpc_error *new) {
 // It is very common to include and extra int and string in an error
 #define SURPLUS_CAPACITY (2 * SLOTS_PER_INT + SLOTS_PER_TIME)
 
-grpc_error *grpc_error_create(grpc_slice file, int line, grpc_slice desc,
+grpc_error *grpc_error_create(const char *file, int line, grpc_slice desc,
                               grpc_error **referencing,
                               size_t num_referencing) {
   GPR_TIMER_BEGIN("grpc_error_create", 0);
@@ -339,7 +345,8 @@ grpc_error *grpc_error_create(grpc_slice file, int line, grpc_slice desc,
   memset(err->times, UINT8_MAX, GRPC_ERROR_TIME_MAX);
 
   internal_set_int(&err, GRPC_ERROR_INT_FILE_LINE, line);
-  internal_set_str(&err, GRPC_ERROR_STR_FILE, file);
+  internal_set_str(&err, GRPC_ERROR_STR_FILE,
+                   grpc_slice_from_static_string(file));
   internal_set_str(&err, GRPC_ERROR_STR_DESCRIPTION, desc);
 
   for (size_t i = 0; i < num_referencing; ++i) {
@@ -756,7 +763,7 @@ grpc_error *grpc_os_error(const char *file, int line, int err,
   return grpc_error_set_str(
       grpc_error_set_str(
           grpc_error_set_int(
-              grpc_error_create(grpc_slice_from_static_string(file), line,
+              grpc_error_create(file, line,
                                 grpc_slice_from_static_string("OS Error"), NULL,
                                 0),
               GRPC_ERROR_INT_ERRNO, err),
@@ -772,7 +779,7 @@ grpc_error *grpc_wsa_error(const char *file, int line, int err,
   grpc_error *error = grpc_error_set_str(
       grpc_error_set_str(
           grpc_error_set_int(
-              grpc_error_create(grpc_slice_from_static_string(file), line,
+              grpc_error_create(file, line,
                                 grpc_slice_from_static_string("OS Error"), NULL,
                                 0),
               GRPC_ERROR_INT_WSA_ERROR, err),
diff --git a/src/core/lib/iomgr/error.h b/src/core/lib/iomgr/error.h
index 2a44fcfe25..34b24d9263 100644
--- a/src/core/lib/iomgr/error.h
+++ b/src/core/lib/iomgr/error.h
@@ -138,7 +138,7 @@ typedef enum {
 const char *grpc_error_string(grpc_error *error);
 
 /// Create an error - but use GRPC_ERROR_CREATE instead
-grpc_error *grpc_error_create(grpc_slice file, int line, grpc_slice desc,
+grpc_error *grpc_error_create(const char *file, int line, grpc_slice desc,
                               grpc_error **referencing, size_t num_referencing);
 /// Create an error (this is the preferred way of generating an error that is
 ///   not due to a system call - for system calls, use GRPC_OS_ERROR or
@@ -148,21 +148,21 @@ grpc_error *grpc_error_create(grpc_slice file, int line, grpc_slice desc,
 /// err = grpc_error_create(x, y, z, r, nr) is equivalent to:
 ///   err = grpc_error_create(x, y, z, NULL, 0);
 ///   for (i=0; i<nr; i++) err = grpc_error_add_child(err, r[i]);
-#define GRPC_ERROR_CREATE_FROM_STATIC_STRING(desc)                     \
-  grpc_error_create(grpc_slice_from_static_string(__FILE__), __LINE__, \
-                    grpc_slice_from_static_string(desc), NULL, 0)
-#define GRPC_ERROR_CREATE_FROM_COPIED_STRING(desc)                     \
-  grpc_error_create(grpc_slice_from_static_string(__FILE__), __LINE__, \
-                    grpc_slice_from_copied_string(desc), NULL, 0)
+#define GRPC_ERROR_CREATE_FROM_STATIC_STRING(desc)                           \
+  grpc_error_create(__FILE__, __LINE__, grpc_slice_from_static_string(desc), \
+                    NULL, 0)
+#define GRPC_ERROR_CREATE_FROM_COPIED_STRING(desc)                           \
+  grpc_error_create(__FILE__, __LINE__, grpc_slice_from_copied_string(desc), \
+                    NULL, 0)
 
 // Create an error that references some other errors. This function adds a
 // reference to each error in errs - it does not consume an existing reference
-#define GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(desc, errs, count) \
-  grpc_error_create(grpc_slice_from_static_string(__FILE__), __LINE__,      \
-                    grpc_slice_from_static_string(desc), errs, count)
-#define GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(desc, errs, count) \
-  grpc_error_create(grpc_slice_from_static_string(__FILE__), __LINE__,      \
-                    grpc_slice_from_copied_string(desc), errs, count)
+#define GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(desc, errs, count)  \
+  grpc_error_create(__FILE__, __LINE__, grpc_slice_from_static_string(desc), \
+                    errs, count)
+#define GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(desc, errs, count)  \
+  grpc_error_create(__FILE__, __LINE__, grpc_slice_from_copied_string(desc), \
+                    errs, count)
 
 //#define GRPC_ERROR_REFCOUNT_DEBUG
 #ifdef GRPC_ERROR_REFCOUNT_DEBUG
diff --git a/src/core/lib/support/stack_lockfree.c b/src/core/lib/support/stack_lockfree.c
index 9d7c9e5a38..c481a3e0dc 100644
--- a/src/core/lib/support/stack_lockfree.c
+++ b/src/core/lib/support/stack_lockfree.c
@@ -72,11 +72,6 @@ typedef union lockfree_node {
 struct gpr_stack_lockfree {
   lockfree_node *entries;
   lockfree_node head; /* An atomic entry describing curr head */
-
-#ifndef NDEBUG
-  /* Bitmap of pushed entries to check for double-push or pop */
-  gpr_atm pushed[(INVALID_ENTRY_INDEX + 1) / (8 * sizeof(gpr_atm))];
-#endif
 };
 
 gpr_stack_lockfree *gpr_stack_lockfree_create(size_t entries) {
@@ -91,9 +86,6 @@ gpr_stack_lockfree *gpr_stack_lockfree_create(size_t entries) {
   /* Clear out all entries */
   memset(stack->entries, 0, entries * sizeof(stack->entries[0]));
   memset(&stack->head, 0, sizeof(stack->head));
-#ifndef NDEBUG
-  memset(&stack->pushed, 0, sizeof(stack->pushed));
-#endif
 
   GPR_ASSERT(sizeof(stack->entries->atm) == sizeof(stack->entries->contents));
 
@@ -130,19 +122,6 @@ int gpr_stack_lockfree_push(gpr_stack_lockfree *stack, int entry) {
   newhead.contents.aba_ctr = ++curent.contents.aba_ctr;
   gpr_atm_no_barrier_store(&stack->entries[entry].atm, curent.atm);
 
-#ifndef NDEBUG
-  /* Check for double push */
-  {
-    int pushed_index = entry / (int)(8 * sizeof(gpr_atm));
-    int pushed_bit = entry % (int)(8 * sizeof(gpr_atm));
-    gpr_atm old_val;
-
-    old_val = gpr_atm_no_barrier_fetch_add(&stack->pushed[pushed_index],
-                                           ((gpr_atm)1 << pushed_bit));
-    GPR_ASSERT((old_val & (((gpr_atm)1) << pushed_bit)) == 0);
-  }
-#endif
-
   do {
     /* Atomically get the existing head value for use */
     head.atm = gpr_atm_no_barrier_load(&(stack->head.atm));
@@ -168,18 +147,6 @@ int gpr_stack_lockfree_pop(gpr_stack_lockfree *stack) {
         gpr_atm_no_barrier_load(&(stack->entries[head.contents.index].atm));
 
   } while (!gpr_atm_no_barrier_cas(&(stack->head.atm), head.atm, newhead.atm));
-#ifndef NDEBUG
-  /* Check for valid pop */
-  {
-    int pushed_index = head.contents.index / (8 * sizeof(gpr_atm));
-    int pushed_bit = head.contents.index % (8 * sizeof(gpr_atm));
-    gpr_atm old_val;
-
-    old_val = gpr_atm_no_barrier_fetch_add(&stack->pushed[pushed_index],
-                                           -((gpr_atm)1 << pushed_bit));
-    GPR_ASSERT((old_val & (((gpr_atm)1) << pushed_bit)) != 0);
-  }
-#endif
 
   return head.contents.index;
 }
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index 3e96d09798..9aa457d792 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -160,6 +160,7 @@ typedef struct {
 } child_call;
 
 struct grpc_call {
+  gpr_refcount ext_ref;
   gpr_arena *arena;
   grpc_completion_queue *cq;
   grpc_polling_entity pollent;
@@ -170,7 +171,7 @@ struct grpc_call {
 
   /* client or server call */
   bool is_client;
-  /** has grpc_call_destroy been called */
+  /** has grpc_call_unref been called */
   bool destroy_called;
   /** flag indicating that cancellation is inherited */
   bool cancellation_is_inherited;
@@ -282,6 +283,10 @@ static void add_init_error(grpc_error **composite, grpc_error *new) {
   *composite = grpc_error_add_child(*composite, new);
 }
 
+void *grpc_call_arena_alloc(grpc_call *call, size_t size) {
+  return gpr_arena_alloc(call->arena, size);
+}
+
 static parent_call *get_or_create_parent_call(grpc_call *call) {
   parent_call *p = (parent_call *)gpr_atm_acq_load(&call->parent_call_atm);
   if (p == NULL) {
@@ -312,6 +317,7 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
       gpr_arena_create(grpc_channel_get_call_size_estimate(args->channel));
   call = gpr_arena_alloc(arena,
                          sizeof(grpc_call) + channel_stack->call_stack_size);
+  gpr_ref_init(&call->ext_ref, 1);
   call->arena = arena;
   *out_call = call;
   call->channel = args->channel;
@@ -346,6 +352,8 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
   gpr_timespec send_deadline =
       gpr_convert_clock_type(args->send_deadline, GPR_CLOCK_MONOTONIC);
 
+  bool immediately_cancel = false;
+
   if (args->parent_call != NULL) {
     child_call *cc = call->child_call =
         gpr_arena_alloc(arena, sizeof(child_call));
@@ -386,8 +394,7 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
     if (args->propagation_mask & GRPC_PROPAGATE_CANCELLATION) {
       call->cancellation_is_inherited = 1;
       if (gpr_atm_acq_load(&args->parent_call->received_final_op_atm)) {
-        cancel_with_error(exec_ctx, call, STATUS_FROM_API_OVERRIDE,
-                          GRPC_ERROR_CANCELLED);
+        immediately_cancel = true;
       }
     }
 
@@ -407,7 +414,7 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
   call->send_deadline = send_deadline;
 
   GRPC_CHANNEL_INTERNAL_REF(args->channel, "call");
-  /* initial refcount dropped by grpc_call_destroy */
+  /* initial refcount dropped by grpc_call_unref */
   grpc_call_element_args call_args = {
       .call_stack = CALL_STACK_FROM_CALL(call),
       .server_transport_data = args->server_transport_data,
@@ -422,6 +429,10 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
     cancel_with_error(exec_ctx, call, STATUS_FROM_SURFACE,
                       GRPC_ERROR_REF(error));
   }
+  if (immediately_cancel) {
+    cancel_with_error(exec_ctx, call, STATUS_FROM_API_OVERRIDE,
+                      GRPC_ERROR_CANCELLED);
+  }
   if (args->cq != NULL) {
     GPR_ASSERT(
         args->pollset_set_alternative == NULL &&
@@ -528,12 +539,16 @@ static void destroy_call(grpc_exec_ctx *exec_ctx, void *call,
   GPR_TIMER_END("destroy_call", 0);
 }
 
-void grpc_call_destroy(grpc_call *c) {
+void grpc_call_ref(grpc_call *c) { gpr_ref(&c->ext_ref); }
+
+void grpc_call_unref(grpc_call *c) {
+  if (!gpr_unref(&c->ext_ref)) return;
+
   child_call *cc = c->child_call;
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
-  GPR_TIMER_BEGIN("grpc_call_destroy", 0);
-  GRPC_API_TRACE("grpc_call_destroy(c=%p)", 1, (c));
+  GPR_TIMER_BEGIN("grpc_call_unref", 0);
+  GRPC_API_TRACE("grpc_call_unref(c=%p)", 1, (c));
 
   if (cc) {
     parent_call *pc = get_parent_call(cc->parent);
@@ -560,7 +575,7 @@ void grpc_call_destroy(grpc_call *c) {
   }
   GRPC_CALL_INTERNAL_UNREF(&exec_ctx, c, "destroy");
   grpc_exec_ctx_finish(&exec_ctx);
-  GPR_TIMER_END("grpc_call_destroy", 0);
+  GPR_TIMER_END("grpc_call_unref", 0);
 }
 
 grpc_call_error grpc_call_cancel(grpc_call *call, void *reserved) {
diff --git a/src/core/lib/surface/server.c b/src/core/lib/surface/server.c
index 38800ea37b..26c81e9aca 100644
--- a/src/core/lib/surface/server.c
+++ b/src/core/lib/surface/server.c
@@ -345,7 +345,7 @@ static void request_matcher_destroy(request_matcher *rm) {
 
 static void kill_zombie(grpc_exec_ctx *exec_ctx, void *elem,
                         grpc_error *error) {
-  grpc_call_destroy(grpc_call_from_top_element(elem));
+  grpc_call_unref(grpc_call_from_top_element(elem));
 }
 
 static void request_matcher_zombify_all_pending_calls(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/transport/static_metadata.c b/src/core/lib/transport/static_metadata.c
index 599d4ad117..862cdaa8e0 100644
--- a/src/core/lib/transport/static_metadata.c
+++ b/src/core/lib/transport/static_metadata.c
@@ -97,23 +97,23 @@ static uint8_t g_bytes[] = {
     101, 105, 102, 45,  110, 111, 110, 101, 45,  109, 97,  116, 99,  104, 105,
     102, 45,  114, 97,  110, 103, 101, 105, 102, 45,  117, 110, 109, 111, 100,
     105, 102, 105, 101, 100, 45,  115, 105, 110, 99,  101, 108, 97,  115, 116,
-    45,  109, 111, 100, 105, 102, 105, 101, 100, 108, 105, 110, 107, 108, 111,
-    99,  97,  116, 105, 111, 110, 109, 97,  120, 45,  102, 111, 114, 119, 97,
-    114, 100, 115, 112, 114, 111, 120, 121, 45,  97,  117, 116, 104, 101, 110,
-    116, 105, 99,  97,  116, 101, 112, 114, 111, 120, 121, 45,  97,  117, 116,
-    104, 111, 114, 105, 122, 97,  116, 105, 111, 110, 114, 97,  110, 103, 101,
-    114, 101, 102, 101, 114, 101, 114, 114, 101, 102, 114, 101, 115, 104, 114,
-    101, 116, 114, 121, 45,  97,  102, 116, 101, 114, 115, 101, 114, 118, 101,
-    114, 115, 101, 116, 45,  99,  111, 111, 107, 105, 101, 115, 116, 114, 105,
-    99,  116, 45,  116, 114, 97,  110, 115, 112, 111, 114, 116, 45,  115, 101,
-    99,  117, 114, 105, 116, 121, 116, 114, 97,  110, 115, 102, 101, 114, 45,
-    101, 110, 99,  111, 100, 105, 110, 103, 118, 97,  114, 121, 118, 105, 97,
-    119, 119, 119, 45,  97,  117, 116, 104, 101, 110, 116, 105, 99,  97,  116,
-    101, 105, 100, 101, 110, 116, 105, 116, 121, 44,  100, 101, 102, 108, 97,
-    116, 101, 105, 100, 101, 110, 116, 105, 116, 121, 44,  103, 122, 105, 112,
-    100, 101, 102, 108, 97,  116, 101, 44,  103, 122, 105, 112, 105, 100, 101,
-    110, 116, 105, 116, 121, 44,  100, 101, 102, 108, 97,  116, 101, 44,  103,
-    122, 105, 112};
+    45,  109, 111, 100, 105, 102, 105, 101, 100, 108, 98,  45,  99,  111, 115,
+    116, 45,  98,  105, 110, 108, 105, 110, 107, 108, 111, 99,  97,  116, 105,
+    111, 110, 109, 97,  120, 45,  102, 111, 114, 119, 97,  114, 100, 115, 112,
+    114, 111, 120, 121, 45,  97,  117, 116, 104, 101, 110, 116, 105, 99,  97,
+    116, 101, 112, 114, 111, 120, 121, 45,  97,  117, 116, 104, 111, 114, 105,
+    122, 97,  116, 105, 111, 110, 114, 97,  110, 103, 101, 114, 101, 102, 101,
+    114, 101, 114, 114, 101, 102, 114, 101, 115, 104, 114, 101, 116, 114, 121,
+    45,  97,  102, 116, 101, 114, 115, 101, 114, 118, 101, 114, 115, 101, 116,
+    45,  99,  111, 111, 107, 105, 101, 115, 116, 114, 105, 99,  116, 45,  116,
+    114, 97,  110, 115, 112, 111, 114, 116, 45,  115, 101, 99,  117, 114, 105,
+    116, 121, 116, 114, 97,  110, 115, 102, 101, 114, 45,  101, 110, 99,  111,
+    100, 105, 110, 103, 118, 97,  114, 121, 118, 105, 97,  119, 119, 119, 45,
+    97,  117, 116, 104, 101, 110, 116, 105, 99,  97,  116, 101, 105, 100, 101,
+    110, 116, 105, 116, 121, 44,  100, 101, 102, 108, 97,  116, 101, 105, 100,
+    101, 110, 116, 105, 116, 121, 44,  103, 122, 105, 112, 100, 101, 102, 108,
+    97,  116, 101, 44,  103, 122, 105, 112, 105, 100, 101, 110, 116, 105, 116,
+    121, 44,  100, 101, 102, 108, 97,  116, 101, 44,  103, 122, 105, 112};
 
 static void static_ref(void *unused) {}
 static void static_unref(grpc_exec_ctx *exec_ctx, void *unused) {}
@@ -223,6 +223,7 @@ grpc_slice_refcount grpc_static_metadata_refcounts[GRPC_STATIC_MDSTR_COUNT] = {
     {&grpc_static_metadata_vtable, &static_sub_refcnt},
     {&grpc_static_metadata_vtable, &static_sub_refcnt},
     {&grpc_static_metadata_vtable, &static_sub_refcnt},
+    {&grpc_static_metadata_vtable, &static_sub_refcnt},
 };
 
 const grpc_slice grpc_static_slice_table[GRPC_STATIC_MDSTR_COUNT] = {
@@ -383,64 +384,67 @@ const grpc_slice grpc_static_slice_table[GRPC_STATIC_MDSTR_COUNT] = {
     {.refcount = &grpc_static_metadata_refcounts[77],
      .data.refcounted = {g_bytes + 791, 13}},
     {.refcount = &grpc_static_metadata_refcounts[78],
-     .data.refcounted = {g_bytes + 804, 4}},
+     .data.refcounted = {g_bytes + 804, 11}},
     {.refcount = &grpc_static_metadata_refcounts[79],
-     .data.refcounted = {g_bytes + 808, 8}},
+     .data.refcounted = {g_bytes + 815, 4}},
     {.refcount = &grpc_static_metadata_refcounts[80],
-     .data.refcounted = {g_bytes + 816, 12}},
+     .data.refcounted = {g_bytes + 819, 8}},
     {.refcount = &grpc_static_metadata_refcounts[81],
-     .data.refcounted = {g_bytes + 828, 18}},
+     .data.refcounted = {g_bytes + 827, 12}},
     {.refcount = &grpc_static_metadata_refcounts[82],
-     .data.refcounted = {g_bytes + 846, 19}},
+     .data.refcounted = {g_bytes + 839, 18}},
     {.refcount = &grpc_static_metadata_refcounts[83],
-     .data.refcounted = {g_bytes + 865, 5}},
+     .data.refcounted = {g_bytes + 857, 19}},
     {.refcount = &grpc_static_metadata_refcounts[84],
-     .data.refcounted = {g_bytes + 870, 7}},
+     .data.refcounted = {g_bytes + 876, 5}},
     {.refcount = &grpc_static_metadata_refcounts[85],
-     .data.refcounted = {g_bytes + 877, 7}},
+     .data.refcounted = {g_bytes + 881, 7}},
     {.refcount = &grpc_static_metadata_refcounts[86],
-     .data.refcounted = {g_bytes + 884, 11}},
+     .data.refcounted = {g_bytes + 888, 7}},
     {.refcount = &grpc_static_metadata_refcounts[87],
-     .data.refcounted = {g_bytes + 895, 6}},
+     .data.refcounted = {g_bytes + 895, 11}},
     {.refcount = &grpc_static_metadata_refcounts[88],
-     .data.refcounted = {g_bytes + 901, 10}},
+     .data.refcounted = {g_bytes + 906, 6}},
     {.refcount = &grpc_static_metadata_refcounts[89],
-     .data.refcounted = {g_bytes + 911, 25}},
+     .data.refcounted = {g_bytes + 912, 10}},
     {.refcount = &grpc_static_metadata_refcounts[90],
-     .data.refcounted = {g_bytes + 936, 17}},
+     .data.refcounted = {g_bytes + 922, 25}},
     {.refcount = &grpc_static_metadata_refcounts[91],
-     .data.refcounted = {g_bytes + 953, 4}},
+     .data.refcounted = {g_bytes + 947, 17}},
     {.refcount = &grpc_static_metadata_refcounts[92],
-     .data.refcounted = {g_bytes + 957, 3}},
+     .data.refcounted = {g_bytes + 964, 4}},
     {.refcount = &grpc_static_metadata_refcounts[93],
-     .data.refcounted = {g_bytes + 960, 16}},
+     .data.refcounted = {g_bytes + 968, 3}},
     {.refcount = &grpc_static_metadata_refcounts[94],
-     .data.refcounted = {g_bytes + 976, 16}},
+     .data.refcounted = {g_bytes + 971, 16}},
     {.refcount = &grpc_static_metadata_refcounts[95],
-     .data.refcounted = {g_bytes + 992, 13}},
+     .data.refcounted = {g_bytes + 987, 16}},
     {.refcount = &grpc_static_metadata_refcounts[96],
-     .data.refcounted = {g_bytes + 1005, 12}},
+     .data.refcounted = {g_bytes + 1003, 13}},
     {.refcount = &grpc_static_metadata_refcounts[97],
-     .data.refcounted = {g_bytes + 1017, 21}},
+     .data.refcounted = {g_bytes + 1016, 12}},
+    {.refcount = &grpc_static_metadata_refcounts[98],
+     .data.refcounted = {g_bytes + 1028, 21}},
 };
 
 uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT] = {
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 4, 6, 6, 8, 8};
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 4, 6, 6, 8, 8};
 
 static const int8_t elems_r[] = {
-    10, 8,   -3,  0,  9,   21,  -76, 22,  0,   10,  -7,  0,  0,  0,  14, 0,
-    13, 12,  11,  0,  0,   0,   0,   0,   0,   0,   0,   0,  0,  0,  0,  0,
-    0,  0,   0,   0,  0,   0,   0,   0,   0,   0,   0,   0,  0,  0,  0,  0,
-    0,  -50, -51, 15, -53, -54, -55, -56, -56, -57, -58, 0,  37, 36, 35, 34,
-    33, 32,  31,  30, 29,  28,  27,  26,  25,  24,  23,  22, 21, 20, 19, 18,
-    17, 16,  15,  14, 13,  12,  11,  10,  13,  12,  11,  10, 9,  8,  7,  0};
+    10,  8,   -3,  0,   9,  21, -77, 22,  0,   10, -7,  0,   0,   0,
+    14,  0,   13,  12,  11, 0,  0,   0,   0,   0,  0,   0,   0,   0,
+    0,   0,   0,   0,   0,  0,  0,   0,   0,   0,  0,   0,   0,   0,
+    0,   0,   0,   0,   0,  0,  0,   -50, -51, 16, -53, -54, -55, -56,
+    -56, -57, -58, -59, 0,  37, 36,  35,  34,  33, 32,  31,  30,  29,
+    28,  27,  26,  25,  24, 23, 22,  21,  20,  19, 18,  17,  16,  15,
+    14,  13,  12,  11,  10, 13, 12,  11,  10,  9,  8,   7,   0};
 static uint32_t elems_phash(uint32_t i) {
   i -= 42;
-  uint32_t x = i % 96;
-  uint32_t y = i / 96;
+  uint32_t x = i % 97;
+  uint32_t y = i / 97;
   uint32_t h = x;
   if (y < GPR_ARRAY_SIZE(elems_r)) {
     uint32_t delta = (uint32_t)elems_r[y];
@@ -450,29 +454,30 @@ static uint32_t elems_phash(uint32_t i) {
 }
 
 static const uint16_t elem_keys[] = {
-    1009, 1010, 1011, 240,  241,  242,  243,  244,  138,  139,  42,   43,
-    429,  430,  431,  911,  912,  913,  712,  713,  1392, 522,  714,  1588,
-    1686, 1784, 4822, 4920, 4951, 5116, 5214, 5312, 5410, 1405, 5508, 5606,
-    5704, 5802, 5900, 5998, 6096, 6194, 6292, 6390, 6488, 6586, 6684, 6782,
-    6880, 6978, 7076, 7174, 7272, 7370, 7468, 7566, 7664, 7762, 7860, 7958,
-    8056, 8154, 8252, 8350, 8448, 1074, 1075, 1076, 1077, 8546, 8644, 8742,
-    8840, 8938, 9036, 9134, 0,    314,  0,    0,    0,    0,    0,    0,
+    1019, 1020, 1021, 242,  243,  244,  245,  246,  139,  140,  42,   43,
+    433,  434,  435,  920,  921,  922,  719,  720,  1406, 527,  721,  1604,
+    1703, 1802, 4871, 4970, 5001, 5168, 5267, 5366, 5465, 1419, 5564, 5663,
+    5762, 5861, 5960, 6059, 6158, 6257, 6356, 6455, 6554, 6653, 6752, 6851,
+    6950, 7049, 7148, 7247, 7346, 7445, 7544, 7643, 7742, 7841, 7940, 8039,
+    8138, 8237, 8336, 8435, 8534, 8633, 1085, 1086, 1087, 1088, 8732, 8831,
+    8930, 9029, 9128, 9227, 9326, 0,    317,  0,    0,    0,    0,    0,
+    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
+    0,    0,    0,    0,    0,    133,  233,  234,  0,    0,    0,    0,
     0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
-    0,    0,    0,    0,    132,  231,  232,  0,    0,    0,    0,    0,
     0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
-    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0};
+    0};
 static const uint8_t elem_idxs[] = {
-    73,  76,  74,  19,  20,  21,  22,  23,  15,  16,  17,  18,  11,  12,  13,
-    3,   4,   5,   0,   1,   41,  6,   2,   69,  48,  55,  24,  25,  26,  27,
+    74,  77,  75,  19,  20,  21,  22,  23,  15,  16,  17,  18,  11,  12,  13,
+    3,   4,   5,   0,   1,   41,  6,   2,   70,  48,  55,  24,  25,  26,  27,
     28,  29,  30,  7,   31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  42,
     43,  44,  45,  46,  47,  49,  50,  51,  52,  53,  54,  56,  57,  58,  59,
-    60,  61,  62,  63,  64,  75,  77,  78,  79,  65,  66,  67,  68,  70,  71,
-    72,  255, 14,  255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
-    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 8,   9,   10};
+    60,  61,  62,  63,  64,  65,  76,  78,  79,  80,  66,  67,  68,  69,  71,
+    72,  73,  255, 14,  255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 8,   9,   10};
 
 grpc_mdelem grpc_static_mdelem_for_static_strings(int a, int b) {
   if (a == -1 || b == -1) return GRPC_MDNULL;
-  uint32_t k = (uint32_t)(a * 98 + b);
+  uint32_t k = (uint32_t)(a * 99 + b);
   uint32_t h = elems_phash(k);
   return h < GPR_ARRAY_SIZE(elem_keys) && elem_keys[h] == k
              ? GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[elem_idxs[h]],
@@ -706,71 +711,75 @@ grpc_mdelem_data grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT] = {
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[78],
-      .data.refcounted = {g_bytes + 804, 4}},
+      .data.refcounted = {g_bytes + 804, 11}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[79],
-      .data.refcounted = {g_bytes + 808, 8}},
+      .data.refcounted = {g_bytes + 815, 4}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[80],
-      .data.refcounted = {g_bytes + 816, 12}},
+      .data.refcounted = {g_bytes + 819, 8}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[81],
-      .data.refcounted = {g_bytes + 828, 18}},
+      .data.refcounted = {g_bytes + 827, 12}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[82],
-      .data.refcounted = {g_bytes + 846, 19}},
+      .data.refcounted = {g_bytes + 839, 18}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[83],
-      .data.refcounted = {g_bytes + 865, 5}},
+      .data.refcounted = {g_bytes + 857, 19}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[84],
-      .data.refcounted = {g_bytes + 870, 7}},
+      .data.refcounted = {g_bytes + 876, 5}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[85],
-      .data.refcounted = {g_bytes + 877, 7}},
+      .data.refcounted = {g_bytes + 881, 7}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[86],
-      .data.refcounted = {g_bytes + 884, 11}},
+      .data.refcounted = {g_bytes + 888, 7}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[87],
-      .data.refcounted = {g_bytes + 895, 6}},
+      .data.refcounted = {g_bytes + 895, 11}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[88],
-      .data.refcounted = {g_bytes + 901, 10}},
+      .data.refcounted = {g_bytes + 906, 6}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[89],
-      .data.refcounted = {g_bytes + 911, 25}},
+      .data.refcounted = {g_bytes + 912, 10}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[90],
-      .data.refcounted = {g_bytes + 936, 17}},
+      .data.refcounted = {g_bytes + 922, 25}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
-    {{.refcount = &grpc_static_metadata_refcounts[16],
-      .data.refcounted = {g_bytes + 200, 10}},
+    {{.refcount = &grpc_static_metadata_refcounts[91],
+      .data.refcounted = {g_bytes + 947, 17}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
-    {{.refcount = &grpc_static_metadata_refcounts[91],
-      .data.refcounted = {g_bytes + 953, 4}},
+    {{.refcount = &grpc_static_metadata_refcounts[16],
+      .data.refcounted = {g_bytes + 200, 10}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[92],
-      .data.refcounted = {g_bytes + 957, 3}},
+      .data.refcounted = {g_bytes + 964, 4}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[93],
-      .data.refcounted = {g_bytes + 960, 16}},
+      .data.refcounted = {g_bytes + 968, 3}},
+     {.refcount = &grpc_static_metadata_refcounts[20],
+      .data.refcounted = {g_bytes + 234, 0}}},
+    {{.refcount = &grpc_static_metadata_refcounts[94],
+      .data.refcounted = {g_bytes + 971, 16}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
@@ -783,24 +792,24 @@ grpc_mdelem_data grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT] = {
       .data.refcounted = {g_bytes + 377, 7}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
       .data.refcounted = {g_bytes + 90, 20}},
-     {.refcount = &grpc_static_metadata_refcounts[94],
-      .data.refcounted = {g_bytes + 976, 16}}},
+     {.refcount = &grpc_static_metadata_refcounts[95],
+      .data.refcounted = {g_bytes + 987, 16}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
       .data.refcounted = {g_bytes + 90, 20}},
      {.refcount = &grpc_static_metadata_refcounts[30],
       .data.refcounted = {g_bytes + 373, 4}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
       .data.refcounted = {g_bytes + 90, 20}},
-     {.refcount = &grpc_static_metadata_refcounts[95],
-      .data.refcounted = {g_bytes + 992, 13}}},
-    {{.refcount = &grpc_static_metadata_refcounts[10],
-      .data.refcounted = {g_bytes + 90, 20}},
      {.refcount = &grpc_static_metadata_refcounts[96],
-      .data.refcounted = {g_bytes + 1005, 12}}},
+      .data.refcounted = {g_bytes + 1003, 13}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
       .data.refcounted = {g_bytes + 90, 20}},
      {.refcount = &grpc_static_metadata_refcounts[97],
-      .data.refcounted = {g_bytes + 1017, 21}}},
+      .data.refcounted = {g_bytes + 1016, 12}}},
+    {{.refcount = &grpc_static_metadata_refcounts[10],
+      .data.refcounted = {g_bytes + 90, 20}},
+     {.refcount = &grpc_static_metadata_refcounts[98],
+      .data.refcounted = {g_bytes + 1028, 21}}},
 };
-const uint8_t grpc_static_accept_encoding_metadata[8] = {0,  73, 74, 75,
-                                                         76, 77, 78, 79};
+const uint8_t grpc_static_accept_encoding_metadata[8] = {0,  74, 75, 76,
+                                                         77, 78, 79, 80};
diff --git a/src/core/lib/transport/static_metadata.h b/src/core/lib/transport/static_metadata.h
index dcbe418edc..84fb316fd6 100644
--- a/src/core/lib/transport/static_metadata.h
+++ b/src/core/lib/transport/static_metadata.h
@@ -44,7 +44,7 @@
 
 #include "src/core/lib/transport/metadata.h"
 
-#define GRPC_STATIC_MDSTR_COUNT 98
+#define GRPC_STATIC_MDSTR_COUNT 99
 extern const grpc_slice grpc_static_slice_table[GRPC_STATIC_MDSTR_COUNT];
 /* ":path" */
 #define GRPC_MDSTR_PATH (grpc_static_slice_table[0])
@@ -205,47 +205,49 @@ extern const grpc_slice grpc_static_slice_table[GRPC_STATIC_MDSTR_COUNT];
 #define GRPC_MDSTR_IF_UNMODIFIED_SINCE (grpc_static_slice_table[76])
 /* "last-modified" */
 #define GRPC_MDSTR_LAST_MODIFIED (grpc_static_slice_table[77])
+/* "lb-cost-bin" */
+#define GRPC_MDSTR_LB_COST_BIN (grpc_static_slice_table[78])
 /* "link" */
-#define GRPC_MDSTR_LINK (grpc_static_slice_table[78])
+#define GRPC_MDSTR_LINK (grpc_static_slice_table[79])
 /* "location" */
-#define GRPC_MDSTR_LOCATION (grpc_static_slice_table[79])
+#define GRPC_MDSTR_LOCATION (grpc_static_slice_table[80])
 /* "max-forwards" */
-#define GRPC_MDSTR_MAX_FORWARDS (grpc_static_slice_table[80])
+#define GRPC_MDSTR_MAX_FORWARDS (grpc_static_slice_table[81])
 /* "proxy-authenticate" */
-#define GRPC_MDSTR_PROXY_AUTHENTICATE (grpc_static_slice_table[81])
+#define GRPC_MDSTR_PROXY_AUTHENTICATE (grpc_static_slice_table[82])
 /* "proxy-authorization" */
-#define GRPC_MDSTR_PROXY_AUTHORIZATION (grpc_static_slice_table[82])
+#define GRPC_MDSTR_PROXY_AUTHORIZATION (grpc_static_slice_table[83])
 /* "range" */
-#define GRPC_MDSTR_RANGE (grpc_static_slice_table[83])
+#define GRPC_MDSTR_RANGE (grpc_static_slice_table[84])
 /* "referer" */
-#define GRPC_MDSTR_REFERER (grpc_static_slice_table[84])
+#define GRPC_MDSTR_REFERER (grpc_static_slice_table[85])
 /* "refresh" */
-#define GRPC_MDSTR_REFRESH (grpc_static_slice_table[85])
+#define GRPC_MDSTR_REFRESH (grpc_static_slice_table[86])
 /* "retry-after" */
-#define GRPC_MDSTR_RETRY_AFTER (grpc_static_slice_table[86])
+#define GRPC_MDSTR_RETRY_AFTER (grpc_static_slice_table[87])
 /* "server" */
-#define GRPC_MDSTR_SERVER (grpc_static_slice_table[87])
+#define GRPC_MDSTR_SERVER (grpc_static_slice_table[88])
 /* "set-cookie" */
-#define GRPC_MDSTR_SET_COOKIE (grpc_static_slice_table[88])
+#define GRPC_MDSTR_SET_COOKIE (grpc_static_slice_table[89])
 /* "strict-transport-security" */
-#define GRPC_MDSTR_STRICT_TRANSPORT_SECURITY (grpc_static_slice_table[89])
+#define GRPC_MDSTR_STRICT_TRANSPORT_SECURITY (grpc_static_slice_table[90])
 /* "transfer-encoding" */
-#define GRPC_MDSTR_TRANSFER_ENCODING (grpc_static_slice_table[90])
+#define GRPC_MDSTR_TRANSFER_ENCODING (grpc_static_slice_table[91])
 /* "vary" */
-#define GRPC_MDSTR_VARY (grpc_static_slice_table[91])
+#define GRPC_MDSTR_VARY (grpc_static_slice_table[92])
 /* "via" */
-#define GRPC_MDSTR_VIA (grpc_static_slice_table[92])
+#define GRPC_MDSTR_VIA (grpc_static_slice_table[93])
 /* "www-authenticate" */
-#define GRPC_MDSTR_WWW_AUTHENTICATE (grpc_static_slice_table[93])
+#define GRPC_MDSTR_WWW_AUTHENTICATE (grpc_static_slice_table[94])
 /* "identity,deflate" */
-#define GRPC_MDSTR_IDENTITY_COMMA_DEFLATE (grpc_static_slice_table[94])
+#define GRPC_MDSTR_IDENTITY_COMMA_DEFLATE (grpc_static_slice_table[95])
 /* "identity,gzip" */
-#define GRPC_MDSTR_IDENTITY_COMMA_GZIP (grpc_static_slice_table[95])
+#define GRPC_MDSTR_IDENTITY_COMMA_GZIP (grpc_static_slice_table[96])
 /* "deflate,gzip" */
-#define GRPC_MDSTR_DEFLATE_COMMA_GZIP (grpc_static_slice_table[96])
+#define GRPC_MDSTR_DEFLATE_COMMA_GZIP (grpc_static_slice_table[97])
 /* "identity,deflate,gzip" */
 #define GRPC_MDSTR_IDENTITY_COMMA_DEFLATE_COMMA_GZIP \
-  (grpc_static_slice_table[97])
+  (grpc_static_slice_table[98])
 
 extern const grpc_slice_refcount_vtable grpc_static_metadata_vtable;
 extern grpc_slice_refcount
@@ -257,7 +259,7 @@ extern grpc_slice_refcount
 #define GRPC_STATIC_METADATA_INDEX(static_slice) \
   ((int)((static_slice).refcount - grpc_static_metadata_refcounts))
 
-#define GRPC_STATIC_MDELEM_COUNT 80
+#define GRPC_STATIC_MDELEM_COUNT 81
 extern grpc_mdelem_data grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT];
 extern uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT];
 /* "grpc-status": "0" */
@@ -428,78 +430,81 @@ extern uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT];
 /* "lb-token": "" */
 #define GRPC_MDELEM_LB_TOKEN_EMPTY \
   (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[55], GRPC_MDELEM_STORAGE_STATIC))
+/* "lb-cost-bin": "" */
+#define GRPC_MDELEM_LB_COST_BIN_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[56], GRPC_MDELEM_STORAGE_STATIC))
 /* "link": "" */
 #define GRPC_MDELEM_LINK_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[56], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[57], GRPC_MDELEM_STORAGE_STATIC))
 /* "location": "" */
 #define GRPC_MDELEM_LOCATION_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[57], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[58], GRPC_MDELEM_STORAGE_STATIC))
 /* "max-forwards": "" */
 #define GRPC_MDELEM_MAX_FORWARDS_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[58], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[59], GRPC_MDELEM_STORAGE_STATIC))
 /* "proxy-authenticate": "" */
 #define GRPC_MDELEM_PROXY_AUTHENTICATE_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[59], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[60], GRPC_MDELEM_STORAGE_STATIC))
 /* "proxy-authorization": "" */
 #define GRPC_MDELEM_PROXY_AUTHORIZATION_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[60], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[61], GRPC_MDELEM_STORAGE_STATIC))
 /* "range": "" */
 #define GRPC_MDELEM_RANGE_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[61], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[62], GRPC_MDELEM_STORAGE_STATIC))
 /* "referer": "" */
 #define GRPC_MDELEM_REFERER_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[62], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[63], GRPC_MDELEM_STORAGE_STATIC))
 /* "refresh": "" */
 #define GRPC_MDELEM_REFRESH_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[63], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[64], GRPC_MDELEM_STORAGE_STATIC))
 /* "retry-after": "" */
 #define GRPC_MDELEM_RETRY_AFTER_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[64], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[65], GRPC_MDELEM_STORAGE_STATIC))
 /* "server": "" */
 #define GRPC_MDELEM_SERVER_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[65], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[66], GRPC_MDELEM_STORAGE_STATIC))
 /* "set-cookie": "" */
 #define GRPC_MDELEM_SET_COOKIE_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[66], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[67], GRPC_MDELEM_STORAGE_STATIC))
 /* "strict-transport-security": "" */
 #define GRPC_MDELEM_STRICT_TRANSPORT_SECURITY_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[67], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[68], GRPC_MDELEM_STORAGE_STATIC))
 /* "transfer-encoding": "" */
 #define GRPC_MDELEM_TRANSFER_ENCODING_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[68], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[69], GRPC_MDELEM_STORAGE_STATIC))
 /* "user-agent": "" */
 #define GRPC_MDELEM_USER_AGENT_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[69], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[70], GRPC_MDELEM_STORAGE_STATIC))
 /* "vary": "" */
 #define GRPC_MDELEM_VARY_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[70], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[71], GRPC_MDELEM_STORAGE_STATIC))
 /* "via": "" */
 #define GRPC_MDELEM_VIA_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[71], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[72], GRPC_MDELEM_STORAGE_STATIC))
 /* "www-authenticate": "" */
 #define GRPC_MDELEM_WWW_AUTHENTICATE_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[72], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[73], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "identity" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[73], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[74], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "deflate" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_DEFLATE \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[74], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[75], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "identity,deflate" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_DEFLATE \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[75], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[76], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "gzip" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_GZIP \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[76], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[77], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "identity,gzip" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_GZIP \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[77], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[78], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "deflate,gzip" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_DEFLATE_COMMA_GZIP \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[78], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[79], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "identity,deflate,gzip" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_DEFLATE_COMMA_GZIP \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[79], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[80], GRPC_MDELEM_STORAGE_STATIC))
 
 grpc_mdelem grpc_static_mdelem_for_static_strings(int a, int b);
 typedef enum {
diff --git a/src/core/tsi/ssl_transport_security.c b/src/core/tsi/ssl_transport_security.c
index 984f745b01..5f4705db92 100644
--- a/src/core/tsi/ssl_transport_security.c
+++ b/src/core/tsi/ssl_transport_security.c
@@ -45,6 +45,7 @@
 #include <ws2tcpip.h>
 #else
 #include <arpa/inet.h>
+#include <sys/socket.h>
 #endif
 
 #include <grpc/support/alloc.h>