Perform glReadPixels with PBOs in the gpu, if PBOs are available.

gpu/command_buffer/client/gles2_implementation.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.
 
 // A class to emulate GLES2 over command buffers.
 
 #include "gpu/command_buffer/client/gles2_implementation.h"
 
 #include <algorithm>
 #include <map>
@@ skipping 2218 matching lines @@
   }
 
   if (bound_pixel_pack_transfer_buffer_id_) {
     GLuint offset = ToGLuint(pixels);
     BufferTracker::Buffer* buffer = GetBoundPixelUnpackTransferBufferIfValid(
         bound_pixel_pack_transfer_buffer_id_,
         "glReadPixels", offset, padded_row_size * height);
     if (buffer && buffer->shm_id() != -1) {
       helper_->ReadPixels(xoffset, yoffset, width, height, format, type,
                           buffer->shm_id(), buffer->shm_offset(),
-                          0, 0);
-      buffer->set_transfer_ready_token(helper_->InsertToken());
+                          0, 0, true);
       CheckGLError();
     }
     return;
   }
 
   if (!pixels) {
     SetGLError(GL_INVALID_OPERATION, "glReadPixels", "pixels = NULL");
     return;
   }
 
@@ skipping 11 matching lines @@
     // NOTE: We must look up the address of the result area AFTER allocation
     // of the transfer buffer since the transfer buffer may be reallocated.
     Result* result = GetResultAs<Result*>();
     if (!result) {
       return;
     }
     *result = 0;  // mark as failed.
     helper_->ReadPixels(
         xoffset, yoffset, width, num_rows, format, type,
         buffer.shm_id(), buffer.offset(),
-        GetResultShmId(), GetResultShmOffset());
+        GetResultShmId(), GetResultShmOffset(),
+        false);
     WaitForCmd();
     if (*result != 0) {
       // when doing a y-flip we have to iterate through top-to-bottom chunks
       // of the dst. The service side handles reversing the rows within a
       // chunk.
       int8* rows_dst;
       if (pack_reverse_row_order_) {
           rows_dst = dest + (height - num_rows) * padded_row_size;
       } else {
           rows_dst = dest;
@@ skipping 885 matching lines @@
     GLsizei n, const GLuint* queries) {
   // TODO(gman): Remove this as queries are not shared resources.
   if (!GetIdHandler(id_namespaces::kQueries)->FreeIds(
       this, n, queries, &GLES2Implementation::DeleteQueriesStub)) {
     SetGLError(
         GL_INVALID_VALUE,
         "glDeleteTextures", "id not created by this context.");
     return;
   }
   // When you delete a query you can't mark its memory as unused until it's
-  // completed.
+  // either completed, or deleted in the gpu process.
   // Note: If you don't do this you won't mess up the service but you will mess
   // up yourself.
 
-  // TODO(gman): Consider making this faster by putting pending quereies
-  // on some queue to be removed when they are finished.
   bool query_pending = false;
   for (GLsizei ii = 0; ii < n; ++ii) {
     QueryTracker::Query* query = query_tracker_->GetQuery(queries[ii]);
-    if (query && query->Pending()) {
+    if (query && !query->CheckResultsAvailable(helper_)) {
       query_pending = true;
       break;
     }
   }
 
+  helper_->DeleteQueriesEXTImmediate(n, queries);
+
   if (query_pending) {
+    // This should make sure that the GPU process have deleted the queries
+    // and given up any claim on the shared memory that goes along with
+    // those queries so that we can safely re-use the shared memory.
     WaitForCmd();
   }
 
   for (GLsizei ii = 0; ii < n; ++ii) {
-    QueryTracker::Query* query = query_tracker_->GetQuery(queries[ii]);
-    if (query && query->Pending()) {
-      if (!query->CheckResultsAvailable(helper_)) {
-        // Should only get here on context lost.
-        MustBeContextLost();
-      }
-    }
     query_tracker_->RemoveQuery(queries[ii], helper_->IsContextLost());
   }
-  helper_->DeleteQueriesEXTImmediate(n, queries);
 }
 
 // TODO(gman): Remove this. Queries are not shared resources.
 void GLES2Implementation::DeleteQueriesStub(
     GLsizei /* n */, const GLuint* /* queries */) {
 }
 
 GLboolean GLES2Implementation::IsQueryEXT(GLuint id) {
   GPU_CLIENT_SINGLE_THREAD_CHECK();
   GPU_CLIENT_LOG("[" << GetLogPrefix() << "] IsQueryEXT(" << id << ")");
@@ skipping 633 matching lines @@
   CheckGLError();
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "gpu/command_buffer/client/gles2_implementation_impl_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu