diff options
| -rw-r--r-- | suspend/1.0/default/SystemSuspend.cpp | 11 | ||||
| -rw-r--r-- | suspend/1.0/default/SystemSuspendUnitTest.cpp | 23 |
2 files changed, 32 insertions, 2 deletions
diff --git a/suspend/1.0/default/SystemSuspend.cpp b/suspend/1.0/default/SystemSuspend.cpp index 5f706717..eae240af 100644 --- a/suspend/1.0/default/SystemSuspend.cpp +++ b/suspend/1.0/default/SystemSuspend.cpp @@ -194,8 +194,15 @@ void SystemSuspend::initAutosuspend() { if (!success) { PLOG(VERBOSE) << "error writing to /sys/power/state"; } - auto callbackLock = std::lock_guard(mCallbackLock); - for (const auto& callback : mCallbacks) { + + // A callback could potentially modify mCallbacks (e.g. via registerCallback). That must + // not result in a deadlock. To that end, we make a copy of mCallbacks and release + // mCallbackLock before calling the copied callbacks. + auto callbackLock = std::unique_lock(mCallbackLock); + auto callbacksCopy = mCallbacks; + callbackLock.unlock(); + + for (const auto& callback : callbacksCopy) { callback->notifyWakeup(success).isOk(); // ignore errors } updateSleepTime(success); diff --git a/suspend/1.0/default/SystemSuspendUnitTest.cpp b/suspend/1.0/default/SystemSuspendUnitTest.cpp index 968e52fa..6d08ec4e 100644 --- a/suspend/1.0/default/SystemSuspendUnitTest.cpp +++ b/suspend/1.0/default/SystemSuspendUnitTest.cpp @@ -335,6 +335,29 @@ TEST_F(SystemSuspendTest, DeadCallback) { // or checking isOk() on every call. checkLoop(3); } + +// Callback that registers another callback. +class CbRegisteringCb : public ISystemSuspendCallback { + public: + CbRegisteringCb(sp<ISystemSuspend> suspendService) : mSuspendService(suspendService) {} + Return<void> notifyWakeup(bool x) { + sp<MockCallback> cb = new MockCallback(nullptr); + cb->disable(); + mSuspendService->registerCallback(cb); + return Void(); + } + + private: + sp<ISystemSuspend> mSuspendService; +}; + +// Tests that callback registering another callback doesn't result in a deadlock. +TEST_F(SystemSuspendTest, CallbackRegisterCallbackNoDeadlock) { + sp<CbRegisteringCb> cb = new CbRegisteringCb(suspendService); + ASSERT_TRUE(suspendService->registerCallback(cb)); + checkLoop(3); +} + } // namespace android int main(int argc, char** argv) { |