| /* |
| * 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. |
| */ |
| |
| #pragma once |
| |
| #include <utils/Errors.h> |
| |
| #include <mutex> |
| |
| using namespace android::surfaceflinger; |
| |
| namespace android { |
| |
| /* |
| * Modulates the vsync-offsets depending on current SurfaceFlinger state. |
| */ |
| class VSyncModulator { |
| private: |
| |
| // Number of frames we'll keep the early phase offsets once they are activated. This acts as a |
| // low-pass filter in case the client isn't quick enough in sending new transactions. |
| const int MIN_EARLY_FRAME_COUNT = 2; |
| |
| public: |
| |
| struct Offsets { |
| nsecs_t sf; |
| nsecs_t app; |
| }; |
| |
| enum TransactionStart { |
| EARLY, |
| NORMAL |
| }; |
| |
| // Sets the phase offsets |
| // |
| // sfEarly: The phase offset when waking up SF early, which happens when marking a transaction |
| // as early. May be the same as late, in which case we don't shift offsets. |
| // sfEarlyGl: Like sfEarly, but only if we used GL composition. If we use both GL composition |
| // and the transaction was marked as early, we'll use sfEarly. |
| // sfLate: The regular SF vsync phase offset. |
| // appEarly: Like sfEarly, but for the app-vsync |
| // appEarlyGl: Like sfEarlyGl, but for the app-vsync. |
| // appLate: The regular app vsync phase offset. |
| void setPhaseOffsets(Offsets early, Offsets earlyGl, Offsets late) { |
| mEarlyOffsets = early; |
| mEarlyGlOffsets = earlyGl; |
| mLateOffsets = late; |
| mOffsets = late; |
| } |
| |
| Offsets getEarlyOffsets() const { |
| return mEarlyOffsets; |
| } |
| |
| Offsets getEarlyGlOffsets() const { |
| return mEarlyGlOffsets; |
| } |
| |
| void setEventThreads(EventThread* sfEventThread, EventThread* appEventThread) { |
| mSfEventThread = sfEventThread; |
| mAppEventThread = appEventThread; |
| } |
| |
| void setTransactionStart(TransactionStart transactionStart) { |
| |
| if (transactionStart == TransactionStart::EARLY) { |
| mRemainingEarlyFrameCount = MIN_EARLY_FRAME_COUNT; |
| } |
| |
| // An early transaction stays an early transaction. |
| if (transactionStart == mTransactionStart || mTransactionStart == TransactionStart::EARLY) { |
| return; |
| } |
| mTransactionStart = transactionStart; |
| updateOffsets(); |
| } |
| |
| void onTransactionHandled() { |
| if (mTransactionStart == TransactionStart::NORMAL) return; |
| mTransactionStart = TransactionStart::NORMAL; |
| updateOffsets(); |
| } |
| |
| void onRefreshed(bool usedRenderEngine) { |
| bool updateOffsetsNeeded = false; |
| if (mRemainingEarlyFrameCount > 0) { |
| mRemainingEarlyFrameCount--; |
| updateOffsetsNeeded = true; |
| } |
| if (usedRenderEngine != mLastFrameUsedRenderEngine) { |
| mLastFrameUsedRenderEngine = usedRenderEngine; |
| updateOffsetsNeeded = true; |
| } |
| if (updateOffsetsNeeded) { |
| updateOffsets(); |
| } |
| } |
| |
| private: |
| |
| void updateOffsets() { |
| const Offsets desired = getOffsets(); |
| const Offsets current = mOffsets; |
| |
| bool changed = false; |
| if (desired.sf != current.sf) { |
| mSfEventThread->setPhaseOffset(desired.sf); |
| changed = true; |
| } |
| if (desired.app != current.app) { |
| mAppEventThread->setPhaseOffset(desired.app); |
| changed = true; |
| } |
| |
| if (changed) { |
| mOffsets = desired; |
| } |
| } |
| |
| Offsets getOffsets() { |
| if (mTransactionStart == TransactionStart::EARLY || mRemainingEarlyFrameCount > 0) { |
| return mEarlyOffsets; |
| } else if (mLastFrameUsedRenderEngine) { |
| return mEarlyGlOffsets; |
| } else { |
| return mLateOffsets; |
| } |
| } |
| |
| Offsets mLateOffsets; |
| Offsets mEarlyOffsets; |
| Offsets mEarlyGlOffsets; |
| |
| EventThread* mSfEventThread = nullptr; |
| EventThread* mAppEventThread = nullptr; |
| |
| std::atomic<Offsets> mOffsets; |
| |
| std::atomic<TransactionStart> mTransactionStart = TransactionStart::NORMAL; |
| std::atomic<bool> mLastFrameUsedRenderEngine = false; |
| std::atomic<int> mRemainingEarlyFrameCount = 0; |
| }; |
| |
| } // namespace android |