[Ozone-GBM] Handle GPU crashes

ui/ozone/platform/dri/screen_manager.cc

 // Copyright 2014 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 "ui/ozone/platform/dri/screen_manager.h"
 
 #include <xf86drmMode.h>
 
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/geometry/rect.h"
@@ skipping 14 matching lines @@
 }  // namespace
 
 ScreenManager::ScreenManager(DriWrapper* dri,
                              ScanoutBufferGenerator* buffer_generator)
     : dri_(dri), buffer_generator_(buffer_generator) {
 }
 
 ScreenManager::~ScreenManager() {
 }
 
+void ScreenManager::AddDisplayController(uint32_t crtc, uint32_t connector) {
+  HardwareDisplayControllers::iterator it = FindDisplayController(crtc);
+  if (it != controllers_.end()) {
+    LOG(WARNING) << "Display controller (crtc=" << crtc << ") already present.";

[alexst (slow to review), 2014/09/04 14:44:45]

Do you expect this to be a regular frequent occurrence? If so does it make sense
to check this at call site? If it's meant as an unforeseen event, we should
DCHECK maybe?

[dnicoara, 2014/09/04 15:12:07]

This is a by-product of having to support a forced initialization for
content_shell and GPU process startup timing on CrOS. So it should really only
happen at start-up or when the GPU process crashes (and is restarted).

Though I did forget to add a comment, since this should be turned into a DCHECK
once display configuration is saner on the async path.

+    return;
+  }
+
+  controllers_.push_back(new HardwareDisplayController(
+      dri_, scoped_ptr<CrtcState>(new CrtcState(dri_, crtc, connector))));
+}
+
 void ScreenManager::RemoveDisplayController(uint32_t crtc) {
   HardwareDisplayControllers::iterator it = FindDisplayController(crtc);
   if (it != controllers_.end()) {
     bool is_mirrored = (*it)->IsMirrored();
     (*it)->RemoveCrtc(crtc);
     if (!is_mirrored)
       controllers_.erase(it);
   }
 }
 
 bool ScreenManager::ConfigureDisplayController(uint32_t crtc,
                                                uint32_t connector,
                                                const gfx::Point& origin,
                                                const drmModeModeInfo& mode) {
   gfx::Rect modeset_bounds(origin, GetModeSize(mode));
   HardwareDisplayControllers::iterator it = FindDisplayController(crtc);
-  HardwareDisplayController* controller = NULL;
-  if (it != controllers_.end()) {
-    controller = *it;
-    // If nothing changed just enable the controller. Note, we perform an exact
-    // comparison on the mode since the refresh rate may have changed.
-    if (SameMode(mode, controller->get_mode()) &&
-        origin == controller->origin() && !controller->IsDisabled())
-      return controller->Enable();
+  DCHECK(controllers_.end() != it) << "Display controller (crtc=" << crtc
+                                   << ") doesn't exist.";
 
-    // Either the mode or the location of the display changed, so exit mirror
-    // mode and configure the display independently. If the caller still wants
-    // mirror mode, subsequent calls configuring the other controllers will
-    // restore mirror mode.
-    if (controller->IsMirrored()) {
-      controller =
-          new HardwareDisplayController(dri_, controller->RemoveCrtc(crtc));
-      controllers_.push_back(controller);
-      it = --controllers_.end();
-    }
+  HardwareDisplayController* controller = *it;
+  controller = *it;
+  // If nothing changed just enable the controller. Note, we perform an exact
+  // comparison on the mode since the refresh rate may have changed.
+  if (SameMode(mode, controller->get_mode()) &&
+      origin == controller->origin() && !controller->IsDisabled())
+    return controller->Enable();
 
-    HardwareDisplayControllers::iterator mirror =
-        FindActiveDisplayControllerByLocation(modeset_bounds);
-    // Handle mirror mode.
-    if (mirror != controllers_.end() && it != mirror)
-      return HandleMirrorMode(it, mirror, crtc, connector);
-  } else {
-    HardwareDisplayControllers::iterator mirror =
-        FindActiveDisplayControllerByLocation(modeset_bounds);
-    if (mirror != controllers_.end()) {
-      (*mirror)->AddCrtc(
-          scoped_ptr<CrtcState>(new CrtcState(dri_, crtc, connector)));
-      return (*mirror)->Enable();
-    }
+  // Either the mode or the location of the display changed, so exit mirror
+  // mode and configure the display independently. If the caller still wants
+  // mirror mode, subsequent calls configuring the other controllers will
+  // restore mirror mode.
+  if (controller->IsMirrored()) {
+    controller =
+        new HardwareDisplayController(dri_, controller->RemoveCrtc(crtc));
+    controllers_.push_back(controller);
+    it = --controllers_.end();
   }
 
-  if (!controller) {
-    controller = new HardwareDisplayController(
-        dri_,
-        scoped_ptr<CrtcState>(new CrtcState(dri_, crtc, connector)));
-    controllers_.push_back(controller);
-  }
+  HardwareDisplayControllers::iterator mirror =
+      FindActiveDisplayControllerByLocation(modeset_bounds);
+  // Handle mirror mode.
+  if (mirror != controllers_.end() && it != mirror)
+    return HandleMirrorMode(it, mirror, crtc, connector);
 
   return ModesetDisplayController(controller, origin, mode);
 }
 
 bool ScreenManager::DisableDisplayController(uint32_t crtc) {
   HardwareDisplayControllers::iterator it = FindDisplayController(crtc);
   if (it != controllers_.end()) {
     if ((*it)->IsMirrored()) {
       HardwareDisplayController* controller =
           new HardwareDisplayController(dri_, (*it)->RemoveCrtc(crtc));
@@ skipping 59 matching lines @@
 
   DCHECK_NE(0u, displays.size());
 
   ScopedDrmPropertyPtr dpms(
       dri_->GetProperty(displays[0]->connector(), "DPMS"));
   if (dpms)
     dri_->SetProperty(displays[0]->connector()->connector_id,
                       dpms->prop_id,
                       DRM_MODE_DPMS_ON);
 
+  AddDisplayController(displays[0]->crtc()->crtc_id,
+                       displays[0]->connector()->connector_id);
   ConfigureDisplayController(displays[0]->crtc()->crtc_id,
                              displays[0]->connector()->connector_id,
                              gfx::Point(),
                              displays[0]->connector()->modes[0]);
 }
 
 bool ScreenManager::ModesetDisplayController(
     HardwareDisplayController* controller,
     const gfx::Point& origin,
     const drmModeModeInfo& mode) {
@@ skipping 30 matching lines @@
 
   // When things go wrong revert back to the previous configuration since
   // it is expected that the configuration would not have changed if
   // things fail.
   (*original)->AddCrtc((*mirror)->RemoveCrtc(crtc));
   (*original)->Enable();
   return false;
 }
 
 }  // namespace ui