From 028508cad5ef63ef9fbd42c14e76658e4fd9ebf2 Mon Sep 17 00:00:00 2001
From: Mathias Agopian <mathias@google.com>
Date: Wed, 25 Jul 2012 21:12:12 -0700
Subject: [PATCH] hopefully fixe a race condition in sf initialization

if we received a vsync event during SF init, we could crash
as not all objects were ready to go.

Change-Id: Ie11b46e3eb1b37a709dd8757843d444f93dd0189
---
 .../DisplayHardware/HWComposer.cpp              | 17 ++++++-----------
 services/surfaceflinger/SurfaceFlinger.cpp      |  8 ++++----
 2 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index 1742f1b2d..0a633f01a 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -118,7 +118,7 @@ HWComposer::HWComposer(
     property_get("debug.sf.no_hw_vsync", value, "0");
     mDebugForceFakeVSync = atoi(value);
 
-    bool needVSyncThread = false;
+    bool needVSyncThread = true;
     int err = hw_get_module(HWC_HARDWARE_MODULE_ID, &mModule);
     ALOGW_IF(err, "%s module not found", HWC_HARDWARE_MODULE_ID);
     if (err == 0) {
@@ -136,6 +136,11 @@ HWComposer::HWComposer(
         }
 
         if (mHwc) {
+            if (hwcHasVersion(mHwc, HWC_DEVICE_API_VERSION_0_3)) {
+                // always turn vsync off when we start
+                mHwc->methods->eventControl(mHwc, HWC_EVENT_VSYNC, 0);
+                needVSyncThread = false;
+            }
             if (mHwc->registerProcs) {
                 mCBContext->hwc = this;
                 mCBContext->procs.invalidate = &hook_invalidate;
@@ -143,17 +148,7 @@ HWComposer::HWComposer(
                 mHwc->registerProcs(mHwc, &mCBContext->procs);
                 memset(mCBContext->procs.zero, 0, sizeof(mCBContext->procs.zero));
             }
-            if (hwcHasVersion(mHwc, HWC_DEVICE_API_VERSION_0_3)) {
-                if (mDebugForceFakeVSync) {
-                    // make sure to turn h/w vsync off in "fake vsync" mode
-                    mHwc->methods->eventControl(mHwc, HWC_EVENT_VSYNC, 0);
-                }
-            } else {
-                needVSyncThread = true;
-            }
         }
-    } else {
-        needVSyncThread = true;
     }
 
     if (needVSyncThread) {
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 2ecdeb8e2..992c7798b 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -406,6 +406,10 @@ status_t SurfaceFlinger::readyToRun()
     EGLSurface surface = hw->getEGLSurface();
     initializeGL(display, surface);
 
+    // start the EventThread
+    mEventThread = new EventThread(this);
+    mEventQueue.setEventThread(mEventThread);
+
     // initialize the H/W composer
     mHwc = new HWComposer(this,
             *static_cast<HWComposer::EventHandler *>(this),
@@ -414,10 +418,6 @@ status_t SurfaceFlinger::readyToRun()
         mHwc->setFrameBuffer(display, surface);
     }
 
-    // start the EventThread
-    mEventThread = new EventThread(this);
-    mEventQueue.setEventThread(mEventThread);
-
     // We're now ready to accept clients...
     mReadyToRunBarrier.open();