command_buffer_gles2: Implement EGL default Display as a global object

gpu/gles2_conform_support/egl/thread_state.cc

+// Copyright (c) 2016 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/gles2_conform_support/egl/thread_state.h"
+
+#include "base/at_exit.h"
+#include "base/command_line.h"
+#include "base/environment.h"
+#include "base/lazy_instance.h"
+#include "base/strings/string_split.h"
+#include "base/strings/string_util.h"
+#include "base/strings/utf_string_conversions.h"
+#include "gpu/command_buffer/client/gles2_lib.h"
+#include "gpu/command_buffer/common/thread_local.h"
+#include "gpu/command_buffer/service/gpu_switches.h"
+#include "gpu/config/gpu_info_collector.h"
+#include "gpu/config/gpu_util.h"
+#include "gpu/gles2_conform_support/egl/context.h"
+#include "gpu/gles2_conform_support/egl/display.h"
+#include "gpu/gles2_conform_support/egl/surface.h"
+#include "gpu/gles2_conform_support/egl/test_support.h"
+#include "ui/gl/gl_context.h"
+#include "ui/gl/gl_surface.h"
+
+// Thread local key for ThreadState instance. Accessed when holding g_egl_lock
+// only, since the initialization can not be Guaranteed otherwise.  Not in
+// anonymous namespace due to Mac OS X 10.6 linker. See gles2_lib.cc.
+static gpu::ThreadLocalKey g_egl_thread_state_key;
+
+namespace {
+base::LazyInstance<base::Lock>::Leaky g_egl_lock;
+int g_egl_active_thread_count;
+
+egl::Display* g_egl_default_display;
+
+#if defined(COMMAND_BUFFER_GLES_LIB_SUPPORT_ONLY)
+// egl::Display is used for comformance tests and command_buffer_gles.  We only
+// need the exit manager for the command_buffer_gles library.
+base::AtExitManager* g_exit_manager;
+#endif
+}  // namespace
+
+namespace egl {
+
+egl::ThreadState* ThreadState::Get() {
+  base::AutoLock lock(g_egl_lock.Get());
+  if (g_egl_active_thread_count == 0) {
+#if defined(COMMAND_BUFFER_GLES_LIB_SUPPORT_ONLY)
+#if defined(COMPONENT_BUILD)
+    if (!g_command_buffer_gles_has_atexit_manager)
+      g_exit_manager = new base::AtExitManager;
+#else
+    g_exit_manager = new base::AtExitManager;
+#endif
+#endif
+    gles2::Initialize();
+
+    if (gfx::GetGLImplementation() == gfx::kGLImplementationNone) {
+      base::CommandLine::StringVector argv;
+      scoped_ptr<base::Environment> env(base::Environment::Create());
+      std::string env_string;
+      env->GetVar("CHROME_COMMAND_BUFFER_GLES2_ARGS", &env_string);
+#if defined(OS_WIN)
+      argv = base::SplitString(base::UTF8ToUTF16(env_string),
+                               base::kWhitespaceUTF16, base::TRIM_WHITESPACE,
+                               base::SPLIT_WANT_NONEMPTY);
+      argv.insert(argv.begin(), base::UTF8ToUTF16("dummy"));
+#else
+      argv =
+          base::SplitString(env_string, base::kWhitespaceASCII,
+                            base::TRIM_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
+      argv.insert(argv.begin(), "dummy");
+#endif
+      base::CommandLine::Init(0, nullptr);
+      base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+      // Need to call both Init and InitFromArgv, since Windows does not use
+      // argc, argv in CommandLine::Init(argc, argv).
+      command_line->InitFromArgv(argv);
+      if (!command_line->HasSwitch(switches::kDisableGpuDriverBugWorkarounds)) {
+        gpu::GPUInfo gpu_info;
+        gpu::CollectBasicGraphicsInfo(&gpu_info);
+        gpu::ApplyGpuDriverBugWorkarounds(gpu_info, command_line);
+      }
+
+      gfx::GLSurface::InitializeOneOff();
+    }
+
+    g_egl_default_display = new egl::Display();
+    g_egl_thread_state_key = gpu::ThreadLocalAlloc();
+  }
+  egl::ThreadState* thread_state = static_cast<egl::ThreadState*>(
+      gpu::ThreadLocalGetValue(g_egl_thread_state_key));
+  if (!thread_state) {
+    thread_state = new egl::ThreadState;
+    gpu::ThreadLocalSetValue(g_egl_thread_state_key, thread_state);
+    ++g_egl_active_thread_count;
+  }
+  return thread_state;
+}
+
+void ThreadState::ReleaseThread() {
+  base::AutoLock lock(g_egl_lock.Get());
+  if (g_egl_active_thread_count == 0)
+    return;
+
+  egl::ThreadState* thread_state = static_cast<egl::ThreadState*>(
+      gpu::ThreadLocalGetValue(g_egl_thread_state_key));
+  if (!thread_state)
+    return;
+  gpu::ThreadLocalFree(g_egl_thread_state_key);

[piman, 2016/02/23 23:37:17]

This should only happen once all the threads have been released, iow in the else
clause below.

[Kimmo Kinnunen, 2016/02/24 07:33:27]

Done.

+
+  --g_egl_active_thread_count;
+  if (g_egl_active_thread_count > 0) {
+    g_egl_default_display->ReleaseCurrent(thread_state);
+    delete thread_state;
+  } else {
+    // First delete the display object, so that it drops the possible refs to
+    // current context.
+    delete g_egl_default_display;
+    g_egl_default_display = nullptr;
+
+    // We can use Surface and Context without lock, since there's no threads
+    // left anymore. Destroy the current context explicitly, in an attempt to
+    // reduce the number of error messages abandoned context would produce.
+    if (thread_state->current_context())

[piman, 2016/02/23 23:37:17]

nit: {} per style

[Kimmo Kinnunen, 2016/02/24 07:33:27]

Done.

+      Context::MakeCurrent(thread_state->current_context(),
+                           thread_state->current_surface()->gl_surface(),
+                           nullptr, nullptr);
+    delete thread_state;
+
+    gles2::Terminate();
+#if defined(COMMAND_BUFFER_GLES_LIB_SUPPORT_ONLY)
+#if defined(COMPONENT_BUILD)
+    if (g_command_buffer_gles_has_atexit_manager)
+      delete g_exit_manager;
+#else
+    delete g_exit_manager;
+#endif
+    g_exit_manager = nullptr;
+#endif
+  }
+}
+
+ThreadState::ThreadState() : error_code_(EGL_SUCCESS) {}
+
+ThreadState::~ThreadState() {}
+
+EGLint ThreadState::ConsumeErrorCode() {
+  EGLint current_error_code = error_code_;
+  error_code_ = EGL_SUCCESS;
+  return current_error_code;
+}
+
+Display* ThreadState::GetDisplay(EGLDisplay dpy) {
+  if (dpy == g_egl_default_display)
+    return g_egl_default_display;
+  return nullptr;
+}
+
+Display* ThreadState::GetDefaultDisplay() {
+  return g_egl_default_display;
+}
+
+void ThreadState::SetCurrent(Surface* surface, Context* context) {
+  DCHECK((surface == nullptr) == (context == nullptr));
+  if (current_context_) {
+    current_context_->set_is_current_in_some_thread(false);
+    current_surface_->set_is_current_in_some_thread(false);
+  }
+  current_surface_ = surface;
+  current_context_ = context;
+  if (current_context_) {
+    current_context_->set_is_current_in_some_thread(true);
+    current_surface_->set_is_current_in_some_thread(true);
+  }
+}
+
+ThreadState::AutoCurrentContextRestore::AutoCurrentContextRestore(
+    ThreadState* thread_state)
+    : thread_state_(thread_state) {}
+
+ThreadState::AutoCurrentContextRestore::~AutoCurrentContextRestore() {
+  if (Context* current_context = thread_state_->current_context())

[piman, 2016/02/23 23:37:17]

nit: needs {} per style (and then so does the else clause)

[Kimmo Kinnunen, 2016/02/24 07:33:27]

Done.

+    current_context->ApplyCurrentContext(
+        thread_state_->current_surface()->gl_surface());
+  else
+    Context::ApplyContextReleased();
+}
+
+void ThreadState::AutoCurrentContextRestore::SetCurrent(Surface* surface,
+                                                        Context* context) {
+  thread_state_->SetCurrent(surface, context);
+}
+
+}  // namespace egl