Re-land: Mark async texture uploads as completed from the upload thread.

gpu/command_buffer/service/query_manager.cc

 // Copyright (c) 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 "gpu/command_buffer/service/query_manager.h"
+
 #include "base/atomicops.h"
 #include "base/bind.h"
 #include "base/logging.h"
+#include "base/shared_memory.h"
 #include "base/time.h"
 #include "gpu/command_buffer/common/gles2_cmd_format.h"
+#include "gpu/command_buffer/service/feature_info.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
-#include "gpu/command_buffer/service/feature_info.h"
 #include "ui/gl/async_pixel_transfer_delegate.h"
 
 namespace gpu {
 namespace gles2 {
 
 class AllSamplesPassedQuery : public QueryManager::Query {
  public:
   AllSamplesPassedQuery(
       QueryManager* manager, GLenum target, int32 shm_id, uint32 shm_offset,
       GLuint service_id);
@@ skipping 146 matching lines @@
     , public base::SupportsWeakPtr<AsyncPixelTransfersCompletedQuery> {
  public:
   AsyncPixelTransfersCompletedQuery(
       QueryManager* manager, GLenum target, int32 shm_id, uint32 shm_offset);
 
   virtual bool Begin() OVERRIDE;
   virtual bool End(uint32 submit_count) OVERRIDE;
   virtual bool Process() OVERRIDE;
   virtual void Destroy(bool have_context) OVERRIDE;
 
-  void MarkAsCompletedCallback() { MarkAsCompleted(1); }
-
  protected:
   virtual ~AsyncPixelTransfersCompletedQuery();
+
+  static void MarkAsCompletedThreadSafe(
+      uint32 submit_count, const gfx::AsyncMemoryParams& mem_params) {
+    DCHECK(mem_params.shared_memory);
+    DCHECK(mem_params.shared_memory->memory());
+    void *data = static_cast<int8*>(mem_params.shared_memory->memory()) +
+        mem_params.shm_data_offset;
+    QuerySync* sync = static_cast<QuerySync*>(data);
+
+    // No need for a MemoryBarrier here as sync->result is not written.
+    sync->process_count = submit_count;
+  }
 };
 
 AsyncPixelTransfersCompletedQuery::AsyncPixelTransfersCompletedQuery(
     QueryManager* manager, GLenum target, int32 shm_id, uint32 shm_offset)
     : Query(manager, target, shm_id, shm_offset) {
 }
 
 bool AsyncPixelTransfersCompletedQuery::Begin() {
   return true;
 }
 
 bool AsyncPixelTransfersCompletedQuery::End(uint32 submit_count) {
-  MarkAsPending(submit_count);
+  gfx::AsyncMemoryParams mem_params;
+  // Get the real shared memory since it might need to be duped to prevent
+  // use-after-free of the memory.
+  Buffer buffer = manager()->decoder()->GetSharedMemoryBuffer(shm_id());

[greggman, 2013/02/11 17:34:09]

Is there any chance this will fail?

[reveman, 2013/02/11 23:27:13]

Good point. Added a check for this.

+  mem_params.shared_memory = buffer.shared_memory;
+  mem_params.shm_size = buffer.size;
+  mem_params.shm_data_offset = shm_offset();
+  mem_params.shm_data_size = sizeof(QuerySync);
 
-  // This will call MarkAsCompleted(1) as a reply to a task on
-  // the async upload thread, such that it occurs after all previous
-  // async transfers have completed.
+  // Ask AsyncPixelTransferDelegate to run completion callback after all
+  // previous async transfers are done. No guarantee that callback is run
+  // on the current thread.
   manager()->decoder()->GetAsyncPixelTransferDelegate()->AsyncNotifyCompletion(
-      base::Bind(
-          &AsyncPixelTransfersCompletedQuery::MarkAsCompletedCallback,
-          AsWeakPtr()));
+      mem_params,
+      base::Bind(AsyncPixelTransfersCompletedQuery::MarkAsCompletedThreadSafe,
+                 submit_count));
 
-  // TODO(epenner): The async task occurs outside the normal
-  // flow, via a callback on this thread. Is there anything
-  // missing or wrong with that?
+  return AddToPendingTransferQueue(submit_count);
+}
 
-  // TODO(epenner): Could we possibly trigger the completion on
-  // the upload thread by writing to the query shared memory
-  // directly?
+bool AsyncPixelTransfersCompletedQuery::Process() {
+  QuerySync* sync = manager()->decoder()->GetSharedMemoryAs<QuerySync*>(
+      shm_id(), shm_offset(), sizeof(*sync));
+  if (!sync)
+    return false;
+
+  // Check if completion callback has been run. sync->process_count atomicity
+  // is guaranteed as this is already used to notify client of a completed
+  // query.
+  if (sync->process_count != submit_count())
+    return true;
+
+  UnmarkAsPending();
   return true;
 }
 
-bool AsyncPixelTransfersCompletedQuery::Process() {
-  NOTREACHED();
-  return true;
-}
-
 void AsyncPixelTransfersCompletedQuery::Destroy(bool /* have_context */) {
   if (!IsDeleted()) {
     MarkAsDeleted();
   }
 }
 
 AsyncPixelTransfersCompletedQuery::~AsyncPixelTransfersCompletedQuery() {
 }
 
 class GetErrorQuery : public QueryManager::Query {
@@ skipping 198 matching lines @@
   return true;
 }
 
 bool QueryManager::ProcessPendingQueries() {
   while (!pending_queries_.empty()) {
     Query* query = pending_queries_.front().get();
     if (!query->Process()) {
       return false;
     }
     if (query->pending()) {
-      return true;
+      break;
     }
     pending_queries_.pop_front();
   }
+  while (!pending_transfer_queries_.empty()) {
+    Query* query = pending_transfer_queries_.front().get();
+    if (!query->Process()) {
+      return false;
+    }
+    if (query->pending()) {
+      break;
+    }
+    pending_transfer_queries_.pop_front();
+  }
 
   return true;
 }
 
 bool QueryManager::HavePendingQueries() {
-  return !pending_queries_.empty();
+  return !pending_queries_.empty() || !pending_transfer_queries_.empty();
 }
 
 bool QueryManager::AddPendingQuery(Query* query, uint32 submit_count) {
   DCHECK(query);
   DCHECK(!query->IsDeleted());
   if (!RemovePendingQuery(query)) {
     return false;
   }
   query->MarkAsPending(submit_count);
   pending_queries_.push_back(query);
   return true;
 }
 
+bool QueryManager::AddPendingTransferQuery(Query* query, uint32 submit_count) {
+  DCHECK(query);
+  DCHECK(!query->IsDeleted());
+  if (!RemovePendingQuery(query)) {
+    return false;
+  }
+  query->MarkAsPending(submit_count);
+  pending_transfer_queries_.push_back(query);
+  return true;
+}
+
 bool QueryManager::RemovePendingQuery(Query* query) {
   DCHECK(query);
   if (query->pending()) {
     // TODO(gman): Speed this up if this is a common operation. This would only
     // happen if you do being/end begin/end on the same query without waiting
     // for the first one to finish.
     for (QueryQueue::iterator it = pending_queries_.begin();
          it != pending_queries_.end(); ++it) {
       if (it->get() == query) {
         pending_queries_.erase(it);
         break;
       }
     }
+    for (QueryQueue::iterator it = pending_transfer_queries_.begin();
+         it != pending_transfer_queries_.end(); ++it) {
+      if (it->get() == query) {
+        pending_transfer_queries_.erase(it);
+        break;
+      }
+    }
     if (!query->MarkAsCompleted(0)) {
       return false;
     }
   }
   return true;
 }
 
 bool QueryManager::BeginQuery(Query* query) {
   DCHECK(query);
   if (!RemovePendingQuery(query)) {
     return false;
   }
   return query->Begin();
 }
 
 bool QueryManager::EndQuery(Query* query, uint32 submit_count) {
   DCHECK(query);
   if (!RemovePendingQuery(query)) {
     return false;
   }
   return query->End(submit_count);
 }
 
 }  // namespace gles2
 }  // namespace gpu