Smarter pollset/pollset_set propagation

For some definition of "smart"... client_channel simply passes along
pollset/pollset_set, removing the need to instantiate a pollset_set in
the subchannel_call_holder: it's now up to the LB policies to handle the
pollset/pollset_set.

1 files changed, 21 insertions, 13 deletions

diff --git a/src/core/ext/lb_policy/pick_first/pick_first.c b/src/core/ext/lb_policy/pick_first/pick_first.c
index 0ffa003946..f6613298be 100644
--- a/src/core/ext/lb_policy/pick_first/pick_first.c
+++ b/src/core/ext/lb_policy/pick_first/pick_first.c
@@ -35,11 +35,13 @@
 
 #include <grpc/support/alloc.h>
 #include "src/core/ext/client_config/lb_policy_registry.h"
+#include "src/core/ext/lb_policy/common.h"
 #include "src/core/lib/transport/connectivity_state.h"
 
 typedef struct pending_pick {
   struct pending_pick *next;
-  grpc_pollset_set *pollset_set;
+  grpc_pollset *pollset;
+  grpc_pollset_set *pollset_set_alternative;
   uint32_t initial_metadata_flags;
   grpc_connected_subchannel **target;
   grpc_closure *on_complete;
@@ -118,8 +120,9 @@ static void pf_shutdown(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   while (pp != NULL) {
     pending_pick *next = pp->next;
     *pp->target = NULL;
-    grpc_pollset_set_del_pollset_set(exec_ctx, p->base.interested_parties,
-                                     pp->pollset_set);
+    del_pollset_or_pollset_set_alternative(exec_ctx, p->base.interested_parties,
+                                           pp->pollset,
+                                           pp->pollset_set_alternative);
     grpc_exec_ctx_enqueue(exec_ctx, pp->on_complete, true, NULL);
     gpr_free(pp);
     pp = next;
@@ -136,8 +139,9 @@ static void pf_cancel_pick(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
   while (pp != NULL) {
     pending_pick *next = pp->next;
     if (pp->target == target) {
-      grpc_pollset_set_del_pollset_set(exec_ctx, p->base.interested_parties,
-                                       pp->pollset_set);
+      del_pollset_or_pollset_set_alternative(
+          exec_ctx, p->base.interested_parties, pp->pollset,
+          pp->pollset_set_alternative);
       *target = NULL;
       grpc_exec_ctx_enqueue(exec_ctx, pp->on_complete, false, NULL);
       gpr_free(pp);
@@ -162,8 +166,9 @@ static void pf_cancel_picks(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     pending_pick *next = pp->next;
     if ((pp->initial_metadata_flags & initial_metadata_flags_mask) ==
         initial_metadata_flags_eq) {
-      grpc_pollset_set_del_pollset_set(exec_ctx, p->base.interested_parties,
-                                       pp->pollset_set);
+      del_pollset_or_pollset_set_alternative(
+          exec_ctx, p->base.interested_parties, pp->pollset,
+          pp->pollset_set_alternative);
       grpc_exec_ctx_enqueue(exec_ctx, pp->on_complete, false, NULL);
       gpr_free(pp);
     } else {
@@ -196,7 +201,8 @@ static void pf_exit_idle(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
 }
 
 static int pf_pick(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
-                   grpc_pollset_set *pollset_set,
+                   grpc_pollset *pollset,
+                   grpc_pollset_set *pollset_set_alternative,
                    grpc_metadata_batch *initial_metadata,
                    uint32_t initial_metadata_flags,
                    grpc_connected_subchannel **target,
@@ -222,11 +228,12 @@ static int pf_pick(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     if (!p->started_picking) {
       start_picking(exec_ctx, p);
     }
-    grpc_pollset_set_add_pollset_set(exec_ctx, p->base.interested_parties,
-                                     pollset_set);
+    add_pollset_or_pollset_set_alternative(exec_ctx, p->base.interested_parties,
+                                           pollset, pollset_set_alternative);
     pp = gpr_malloc(sizeof(*pp));
     pp->next = p->pending_picks;
-    pp->pollset_set = pollset_set;
+    pp->pollset = pollset;
+    pp->pollset_set_alternative = pollset_set_alternative;
     pp->target = target;
     pp->initial_metadata_flags = initial_metadata_flags;
     pp->on_complete = on_complete;
@@ -306,8 +313,9 @@ static void pf_connectivity_changed(grpc_exec_ctx *exec_ctx, void *arg,
         while ((pp = p->pending_picks)) {
           p->pending_picks = pp->next;
           *pp->target = selected;
-          grpc_pollset_set_del_pollset_set(exec_ctx, p->base.interested_parties,
-                                           pp->pollset_set);
+          del_pollset_or_pollset_set_alternative(
+              exec_ctx, p->base.interested_parties, pp->pollset,
+              pp->pollset_set_alternative);
           grpc_exec_ctx_enqueue(exec_ctx, pp->on_complete, true, NULL);
           gpr_free(pp);
         }