Assert sequence validity on non-thread-safe RefCount manipulations (2)

mojo/public/cpp/bindings/lib/multiplex_router.cc

Index: mojo/public/cpp/bindings/lib/multiplex_router.cc
diff --git a/mojo/public/cpp/bindings/lib/multiplex_router.cc b/mojo/public/cpp/bindings/lib/multiplex_router.cc
index 2da459ae8f8ca5ee8704164bbeefaad3a93a2c88..005731ee4e207e24fa5f1a26634f21f25b2ae05e 100644
--- a/mojo/public/cpp/bindings/lib/multiplex_router.cc
+++ b/mojo/public/cpp/bindings/lib/multiplex_router.cc
@@ -431,6 +431,10 @@ InterfaceId MultiplexRouter::AssociateInterface(
   uint32_t id = 0;
   {
     MayAutoLock locker(&lock_);
+    // Relax the cross-thread access restriction to non-thread-safe RefCount.
+    // The lock above protects |endpoint|.
+    base::ScopedAllowCrossThreadRefCountAccess

[yzshen1, 2017/03/06 17:53:52]

Can this opt-out be configured with a type (in this case
MultiplexRouter::Endpoint), instead on each callsite? That would be less
verbose.

+        allow_cross_thread_ref_count_access;
     do {
       if (next_interface_id_value_ >= kInterfaceIdNamespaceMask)
         next_interface_id_value_ = 1;
@@ -468,6 +472,10 @@ ScopedInterfaceEndpointHandle MultiplexRouter::CreateLocalEndpointHandle(
     return ScopedInterfaceEndpointHandle();
 
   MayAutoLock locker(&lock_);
+  // Relax the cross-thread access restriction to non-thread-safe RefCount.
+  // The lock above protects |endpoint|.
+  base::ScopedAllowCrossThreadRefCountAccess
+      allow_cross_thread_ref_count_access;
   bool inserted = false;
   InterfaceEndpoint* endpoint = FindOrInsertEndpoint(id, &inserted);
   if (inserted) {
@@ -496,6 +504,10 @@ void MultiplexRouter::CloseEndpointHandle(
     return;
 
   MayAutoLock locker(&lock_);
+  // Relax the cross-thread access restriction to non-thread-safe RefCount.
+  // The lock above protects |endpoint|.
+  base::ScopedAllowCrossThreadRefCountAccess
+      allow_cross_thread_ref_count_access;
   DCHECK(base::ContainsKey(endpoints_, id));
   InterfaceEndpoint* endpoint = endpoints_[id].get();
   DCHECK(!endpoint->client());
@@ -520,6 +532,10 @@ InterfaceEndpointController* MultiplexRouter::AttachEndpointClient(
   DCHECK(client);
 
   MayAutoLock locker(&lock_);
+  // Relax the cross-thread access restriction to non-thread-safe RefCount.
+  // The lock above protects |endpoint|.
+  base::ScopedAllowCrossThreadRefCountAccess
+      allow_cross_thread_ref_count_access;
   DCHECK(base::ContainsKey(endpoints_, id));
 
   InterfaceEndpoint* endpoint = endpoints_[id].get();
@@ -692,6 +708,10 @@ void MultiplexRouter::OnPipeConnectionError() {
 
   scoped_refptr<MultiplexRouter> protector(this);
   MayAutoLock locker(&lock_);
+  // Relax the cross-thread access restriction to non-thread-safe RefCount.
+  // The lock above protects |endpoint|.
+  base::ScopedAllowCrossThreadRefCountAccess
+      allow_cross_thread_ref_count_access;
 
   encountered_error_ = true;
 
@@ -717,6 +737,10 @@ void MultiplexRouter::ProcessTasks(
     ClientCallBehavior client_call_behavior,
     base::SingleThreadTaskRunner* current_task_runner) {
   AssertLockAcquired();
+  // Relax the cross-thread access restriction to non-thread-safe RefCount.
+  // The lock above protects |endpoint|.
+  base::ScopedAllowCrossThreadRefCountAccess
+      allow_cross_thread_ref_count_access;
 
   if (posted_to_process_tasks_)
     return;