SurfaceFlinger: Emit TransactionCompleted callbacks directly.
Transaction complete callbacks (BLAST Buffer release callbacks), are
emitted from a TransactionCompletedThread. There's no clear reason
for this behavior, as the actual runtime is exceedingly minimal. This
opens us to scheduling delays when we call
TransactionCompletedThread.sendCallbacks. In this CL we both remove the
threaded nature of TransactionCompletedThread, and also take advantage
of it running on the main thread to reduce some unnecessary copying and
further reduce its runtime.
Bug: 176691195
Test: Existing tests pass
Change-Id: Ib1661df24c4a2ee39fc28c29a395158ce0ee7b7f
diff --git a/services/surfaceflinger/TransactionCallbackInvoker.cpp b/services/surfaceflinger/TransactionCallbackInvoker.cpp
new file mode 100644
index 0000000..a78510e
--- /dev/null
+++ b/services/surfaceflinger/TransactionCallbackInvoker.cpp
@@ -0,0 +1,298 @@
+/*
+ * Copyright 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// TODO(b/129481165): remove the #pragma below and fix conversion issues
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wconversion"
+
+//#define LOG_NDEBUG 0
+#undef LOG_TAG
+#define LOG_TAG "TransactionCallbackInvoker"
+#define ATRACE_TAG ATRACE_TAG_GRAPHICS
+
+#include "TransactionCallbackInvoker.h"
+
+#include <cinttypes>
+
+#include <binder/IInterface.h>
+#include <utils/RefBase.h>
+
+namespace android {
+
+// Returns 0 if they are equal
+// <0 if the first id that doesn't match is lower in c2 or all ids match but c2 is shorter
+// >0 if the first id that doesn't match is greater in c2 or all ids match but c2 is longer
+//
+// See CallbackIdsHash for a explaniation of why this works
+static int compareCallbackIds(const std::vector<CallbackId>& c1,
+ const std::vector<CallbackId>& c2) {
+ if (c1.empty()) {
+ return !c2.empty();
+ }
+ return c1.front() - c2.front();
+}
+
+TransactionCallbackInvoker::~TransactionCallbackInvoker() {
+ {
+ std::lock_guard lock(mMutex);
+ for (const auto& [listener, transactionStats] : mCompletedTransactions) {
+ listener->unlinkToDeath(mDeathRecipient);
+ }
+ }
+}
+
+status_t TransactionCallbackInvoker::startRegistration(const ListenerCallbacks& listenerCallbacks) {
+ std::lock_guard lock(mMutex);
+
+ auto [itr, inserted] = mRegisteringTransactions.insert(listenerCallbacks);
+ auto& [listener, callbackIds] = listenerCallbacks;
+
+ if (inserted) {
+ if (mCompletedTransactions.count(listener) == 0) {
+ status_t err = listener->linkToDeath(mDeathRecipient);
+ if (err != NO_ERROR) {
+ ALOGE("cannot add callback because linkToDeath failed, err: %d", err);
+ return err;
+ }
+ }
+ auto& transactionStatsDeque = mCompletedTransactions[listener];
+ transactionStatsDeque.emplace_back(callbackIds);
+ }
+
+ return NO_ERROR;
+}
+
+status_t TransactionCallbackInvoker::endRegistration(const ListenerCallbacks& listenerCallbacks) {
+ std::lock_guard lock(mMutex);
+
+ auto itr = mRegisteringTransactions.find(listenerCallbacks);
+ if (itr == mRegisteringTransactions.end()) {
+ ALOGE("cannot end a registration that does not exist");
+ return BAD_VALUE;
+ }
+
+ mRegisteringTransactions.erase(itr);
+
+ return NO_ERROR;
+}
+
+bool TransactionCallbackInvoker::isRegisteringTransaction(
+ const sp<IBinder>& transactionListener, const std::vector<CallbackId>& callbackIds) {
+ ListenerCallbacks listenerCallbacks(transactionListener, callbackIds);
+
+ auto itr = mRegisteringTransactions.find(listenerCallbacks);
+ return itr != mRegisteringTransactions.end();
+}
+
+status_t TransactionCallbackInvoker::registerPendingCallbackHandle(
+ const sp<CallbackHandle>& handle) {
+ std::lock_guard lock(mMutex);
+
+ // If we can't find the transaction stats something has gone wrong. The client should call
+ // startRegistration before trying to register a pending callback handle.
+ TransactionStats* transactionStats;
+ status_t err = findTransactionStats(handle->listener, handle->callbackIds, &transactionStats);
+ if (err != NO_ERROR) {
+ ALOGE("cannot find transaction stats");
+ return err;
+ }
+
+ mPendingTransactions[handle->listener][handle->callbackIds]++;
+ return NO_ERROR;
+}
+
+status_t TransactionCallbackInvoker::finalizePendingCallbackHandles(
+ const std::deque<sp<CallbackHandle>>& handles, const std::vector<JankData>& jankData) {
+ if (handles.empty()) {
+ return NO_ERROR;
+ }
+ std::lock_guard lock(mMutex);
+
+ for (const auto& handle : handles) {
+ auto listener = mPendingTransactions.find(handle->listener);
+ if (listener != mPendingTransactions.end()) {
+ auto& pendingCallbacks = listener->second;
+ auto pendingCallback = pendingCallbacks.find(handle->callbackIds);
+
+ if (pendingCallback != pendingCallbacks.end()) {
+ auto& pendingCount = pendingCallback->second;
+
+ // Decrease the pending count for this listener
+ if (--pendingCount == 0) {
+ pendingCallbacks.erase(pendingCallback);
+ }
+ } else {
+ ALOGW("there are more latched callbacks than there were registered callbacks");
+ }
+ if (listener->second.size() == 0) {
+ mPendingTransactions.erase(listener);
+ }
+ } else {
+ ALOGW("cannot find listener in mPendingTransactions");
+ }
+
+ status_t err = addCallbackHandle(handle, jankData);
+ if (err != NO_ERROR) {
+ ALOGE("could not add callback handle");
+ return err;
+ }
+ }
+
+ return NO_ERROR;
+}
+
+status_t TransactionCallbackInvoker::registerUnpresentedCallbackHandle(
+ const sp<CallbackHandle>& handle) {
+ std::lock_guard lock(mMutex);
+
+ return addCallbackHandle(handle, std::vector<JankData>());
+}
+
+status_t TransactionCallbackInvoker::findTransactionStats(
+ const sp<IBinder>& listener, const std::vector<CallbackId>& callbackIds,
+ TransactionStats** outTransactionStats) {
+ auto& transactionStatsDeque = mCompletedTransactions[listener];
+
+ // Search back to front because the most recent transactions are at the back of the deque
+ auto itr = transactionStatsDeque.rbegin();
+ for (; itr != transactionStatsDeque.rend(); itr++) {
+ if (compareCallbackIds(itr->callbackIds, callbackIds) == 0) {
+ *outTransactionStats = &(*itr);
+ return NO_ERROR;
+ }
+ }
+
+ ALOGE("could not find transaction stats");
+ return BAD_VALUE;
+}
+
+status_t TransactionCallbackInvoker::addCallbackHandle(const sp<CallbackHandle>& handle,
+ const std::vector<JankData>& jankData) {
+ // If we can't find the transaction stats something has gone wrong. The client should call
+ // startRegistration before trying to add a callback handle.
+ TransactionStats* transactionStats;
+ status_t err = findTransactionStats(handle->listener, handle->callbackIds, &transactionStats);
+ if (err != NO_ERROR) {
+ return err;
+ }
+
+ transactionStats->latchTime = handle->latchTime;
+ // If the layer has already been destroyed, don't add the SurfaceControl to the callback.
+ // The client side keeps a sp<> to the SurfaceControl so if the SurfaceControl has been
+ // destroyed the client side is dead and there won't be anyone to send the callback to.
+ sp<IBinder> surfaceControl = handle->surfaceControl.promote();
+ if (surfaceControl) {
+ FrameEventHistoryStats eventStats(handle->frameNumber,
+ handle->gpuCompositionDoneFence->getSnapshot().fence,
+ handle->compositorTiming, handle->refreshStartTime,
+ handle->dequeueReadyTime);
+ transactionStats->surfaceStats.emplace_back(surfaceControl, handle->acquireTime,
+ handle->previousReleaseFence,
+ handle->transformHint, eventStats, jankData);
+ }
+ return NO_ERROR;
+}
+
+void TransactionCallbackInvoker::addPresentFence(const sp<Fence>& presentFence) {
+ std::lock_guard<std::mutex> lock(mMutex);
+ mPresentFence = presentFence;
+}
+
+void TransactionCallbackInvoker::sendCallbacks() {
+ std::lock_guard lock(mMutex);
+
+ // For each listener
+ auto completedTransactionsItr = mCompletedTransactions.begin();
+ while (completedTransactionsItr != mCompletedTransactions.end()) {
+ auto& [listener, transactionStatsDeque] = *completedTransactionsItr;
+ ListenerStats listenerStats;
+ listenerStats.listener = listener;
+
+ // For each transaction
+ auto transactionStatsItr = transactionStatsDeque.begin();
+ while (transactionStatsItr != transactionStatsDeque.end()) {
+ auto& transactionStats = *transactionStatsItr;
+
+ // If this transaction is still registering, it is not safe to send a callback
+ // because there could be surface controls that haven't been added to
+ // transaction stats or mPendingTransactions.
+ if (isRegisteringTransaction(listener, transactionStats.callbackIds)) {
+ break;
+ }
+
+ // If we are still waiting on the callback handles for this transaction, stop
+ // here because all transaction callbacks for the same listener must come in order
+ auto pendingTransactions = mPendingTransactions.find(listener);
+ if (pendingTransactions != mPendingTransactions.end() &&
+ pendingTransactions->second.count(transactionStats.callbackIds) != 0) {
+ break;
+ }
+
+ // If the transaction has been latched
+ if (transactionStats.latchTime >= 0) {
+ if (!mPresentFence) {
+ break;
+ }
+ transactionStats.presentFence = mPresentFence;
+ }
+
+ // Remove the transaction from completed to the callback
+ listenerStats.transactionStats.push_back(std::move(transactionStats));
+ transactionStatsItr = transactionStatsDeque.erase(transactionStatsItr);
+ }
+ // If the listener has completed transactions
+ if (!listenerStats.transactionStats.empty()) {
+ // If the listener is still alive
+ if (listener->isBinderAlive()) {
+ // Send callback. The listener stored in listenerStats
+ // comes from the cross-process setTransactionState call to
+ // SF. This MUST be an ITransactionCompletedListener. We
+ // keep it as an IBinder due to consistency reasons: if we
+ // interface_cast at the IPC boundary when reading a Parcel,
+ // we get pointers that compare unequal in the SF process.
+ interface_cast<ITransactionCompletedListener>(listenerStats.listener)
+ ->onTransactionCompleted(listenerStats);
+ if (transactionStatsDeque.empty()) {
+ listener->unlinkToDeath(mDeathRecipient);
+ completedTransactionsItr =
+ mCompletedTransactions.erase(completedTransactionsItr);
+ } else {
+ completedTransactionsItr++;
+ }
+ } else {
+ completedTransactionsItr =
+ mCompletedTransactions.erase(completedTransactionsItr);
+ }
+ } else {
+ completedTransactionsItr++;
+ }
+ }
+
+ if (mPresentFence) {
+ mPresentFence.clear();
+ }
+}
+
+// -----------------------------------------------------------------------
+
+CallbackHandle::CallbackHandle(const sp<IBinder>& transactionListener,
+ const std::vector<CallbackId>& ids, const sp<IBinder>& sc)
+ : listener(transactionListener), callbackIds(ids), surfaceControl(sc) {}
+
+} // namespace android
+
+// TODO(b/129481165): remove the #pragma below and fix conversion issues
+#pragma clang diagnostic pop // ignored "-Wconversion"