sf: Fix incorrect state reporting in dumpsys
Dumpsys utility accesses layer compositionType variable
with out proper protection. These variables are modified
during hwc_prepare call. Existing HAL lock protection is not
sufficient to address this issue. Failure to do this will
result in incorrect state reporting in dumpsys.
A new displayLock mutex in HWComposer will be used in both
dumpsys and draw calls to ensure correct state is accessed.
Change-Id: I8a57de59525adc0e089b3bed95c067c01e42b666
(cherry picked from commit e54506b81a3b81683056ad48294e37d6b4b4e36b)
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index 02c31ff..2dad005 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -635,6 +635,7 @@
}
status_t HWComposer::prepare() {
+ Mutex::Autolock _l(mDisplayLock);
for (size_t i=0 ; i<mNumDisplays ; i++) {
DisplayData& disp(mDisplayData[i]);
if (disp.framebufferTarget) {
@@ -1145,6 +1146,7 @@
}
void HWComposer::dump(String8& result) const {
+ Mutex::Autolock _l(mDisplayLock);
if (mHwc) {
result.appendFormat("Hardware Composer state (version %08x):\n", hwcApiVersion(mHwc));
result.appendFormat(" mDebugForceFakeVSync=%d\n", mDebugForceFakeVSync);
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.h b/services/surfaceflinger/DisplayHardware/HWComposer.h
index 28d8c65..cc98b4c 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.h
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.h
@@ -354,6 +354,8 @@
// mLists[i>0] can be NULL. that display is to be ignored
struct hwc_display_contents_1* mLists[MAX_HWC_DISPLAYS];
DisplayData mDisplayData[MAX_HWC_DISPLAYS];
+ // protect mDisplayData from races between prepare and dump
+ mutable Mutex mDisplayLock;
size_t mNumDisplays;
cb_context* mCBContext;