Verify resource provider sync tokens before sending to parent.

cc/resources/resource_provider.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/resources/resource_provider.h"
 
 #include <algorithm>
 #include <limits>
 
 #include "base/atomic_sequence_num.h"
@@ skipping 1117 matching lines @@
   ChildMap::const_iterator it = children_.find(child);
   DCHECK(it != children_.end());
   DCHECK(!it->second.marked_for_deletion);
   return it->second.child_to_parent_map;
 }
 
 void ResourceProvider::PrepareSendToParent(const ResourceIdArray& resources,
                                            TransferableResourceArray* list) {
   DCHECK(thread_checker_.CalledOnValidThread());
   GLES2Interface* gl = ContextGL();
-  bool need_sync_token = false;
+
+  gpu::SyncToken new_sync_token;
+  std::vector<GLbyte*> unverified_sync_tokens;
   for (ResourceIdArray::const_iterator it = resources.begin();
        it != resources.end();
        ++it) {
     TransferableResource resource;
     TransferResource(gl, *it, &resource);
-    need_sync_token |= (!resource.mailbox_holder.sync_token.HasData() &&
-                        !resource.is_software);
+    if (!resource.is_software &&
+        !resource.mailbox_holder.sync_token.HasData()) {
+      if (!new_sync_token.HasData()) {
+        const uint64_t fence_sync = gl->InsertFenceSyncCHROMIUM();
+        gl->OrderingBarrierCHROMIUM();
+        GenUnverifiedSyncTokenCHROMIUM(fence_sync, new_sync_token.GetData());
+        unverified_sync_tokens.push_back(new_sync_token.GetData());

[piman, 2015/11/26 02:32:44]

Actually, the VerifySyncTokensCHROMIUM below will tag the local copy of the
SyncToken, new_sync_token, not the copy in the mailbox_holder.

I think you want to move this line after l.1154 and be
unverified_sync_tokens.push_back(resource.mailbox_holder.sync_token.GetData());

Or maybe even combine that with the code on l.1156, i.e. remove the else.

[David Yen, 2015/12/08 00:57:56]

Done.

+      }
+      resource.mailbox_holder.sync_token = new_sync_token;
+    } else if (!resource.mailbox_holder.sync_token.verified_flush()) {
+      unverified_sync_tokens.push_back(
+          resource.mailbox_holder.sync_token.GetData());
+    }
+
     ++resources_.find(*it)->second.exported_count;
     list->push_back(resource);
   }
-  if (need_sync_token &&
-      output_surface_->capabilities().delegated_sync_points_required) {
-    gpu::SyncToken sync_token(gl->InsertSyncPointCHROMIUM());
-    for (TransferableResourceArray::iterator it = list->begin();
-         it != list->end();
-         ++it) {
-      if (!it->mailbox_holder.sync_token.HasData())
-        it->mailbox_holder.sync_token = sync_token;
-    }
+
+  if (!unverified_sync_tokens.empty()) {
+    gl->VerifySyncTokensCHROMIUM(unverified_sync_tokens.data(),
+                                 unverified_sync_tokens.size());
   }
 }
 
 void ResourceProvider::ReceiveFromChild(
     int child, const TransferableResourceArray& resources) {
   DCHECK(thread_checker_.CalledOnValidThread());
   GLES2Interface* gl = ContextGL();
   Child& child_info = children_.find(child)->second;
   DCHECK(!child_info.marked_for_deletion);
   for (TransferableResourceArray::const_iterator it = resources.begin();
@@ skipping 493 matching lines @@
       const int kImportance = 2;
       pmd->CreateSharedGlobalAllocatorDump(guid);
       pmd->AddOwnershipEdge(dump->guid(), guid, kImportance);
     }
   }
 
   return true;
 }
 
 }  // namespace cc