1 files changed, 335 insertions, 0 deletions
diff --git a/libs/hwui/renderthread/RenderThread.cpp b/libs/hwui/renderthread/RenderThread.cpp
new file mode 100644
index 000000000000..4a4e2540dd6f
--- /dev/null
+++ b/libs/hwui/renderthread/RenderThread.cpp
@@ -0,0 +1,335 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#define LOG_TAG "RenderThread"
+
+#include "RenderThread.h"
+
+#include <gui/DisplayEventReceiver.h>
+#include <utils/Log.h>
+
+#include "CanvasContext.h"
+#include "RenderProxy.h"
+
+namespace android {
+using namespace uirenderer::renderthread;
+ANDROID_SINGLETON_STATIC_INSTANCE(RenderThread);
+
+namespace uirenderer {
+namespace renderthread {
+
+// Number of events to read at a time from the DisplayEventReceiver pipe.
+// The value should be large enough that we can quickly drain the pipe
+// using just a few large reads.
+static const size_t EVENT_BUFFER_SIZE = 100;
+
+// Slight delay to give the UI time to push us a new frame before we replay
+static const int DISPATCH_FRAME_CALLBACKS_DELAY = 4;
+
+TaskQueue::TaskQueue() : mHead(0), mTail(0) {}
+
+RenderTask* TaskQueue::next() {
+    RenderTask* ret = mHead;
+    if (ret) {
+        mHead = ret->mNext;
+        if (!mHead) {
+            mTail = 0;
+        }
+        ret->mNext = 0;
+    }
+    return ret;
+}
+
+RenderTask* TaskQueue::peek() {
+    return mHead;
+}
+
+void TaskQueue::queue(RenderTask* task) {
+    // Since the RenderTask itself forms the linked list it is not allowed
+    // to have the same task queued twice
+    LOG_ALWAYS_FATAL_IF(task->mNext || mTail == task, "Task is already in the queue!");
+    if (mTail) {
+        // Fast path if we can just append
+        if (mTail->mRunAt <= task->mRunAt) {
+            mTail->mNext = task;
+            mTail = task;
+        } else {
+            // Need to find the proper insertion point
+            RenderTask* previous = 0;
+            RenderTask* next = mHead;
+            while (next && next->mRunAt <= task->mRunAt) {
+                previous = next;
+                next = next->mNext;
+            }
+            if (!previous) {
+                task->mNext = mHead;
+                mHead = task;
+            } else {
+                previous->mNext = task;
+                if (next) {
+                    task->mNext = next;
+                } else {
+                    mTail = task;
+                }
+            }
+        }
+    } else {
+        mTail = mHead = task;
+    }
+}
+
+void TaskQueue::queueAtFront(RenderTask* task) {
+    if (mTail) {
+        task->mNext = mHead;
+        mHead = task;
+    } else {
+        mTail = mHead = task;
+    }
+}
+
+void TaskQueue::remove(RenderTask* task) {
+    // TaskQueue is strict here to enforce that users are keeping track of
+    // their RenderTasks due to how their memory is managed
+    LOG_ALWAYS_FATAL_IF(!task->mNext && mTail != task,
+            "Cannot remove a task that isn't in the queue!");
+
+    // If task is the head we can just call next() to pop it off
+    // Otherwise we need to scan through to find the task before it
+    if (peek() == task) {
+        next();
+    } else {
+        RenderTask* previous = mHead;
+        while (previous->mNext != task) {
+            previous = previous->mNext;
+        }
+        previous->mNext = task->mNext;
+        if (mTail == task) {
+            mTail = previous;
+        }
+    }
+}
+
+class DispatchFrameCallbacks : public RenderTask {
+private:
+    RenderThread* mRenderThread;
+public:
+    DispatchFrameCallbacks(RenderThread* rt) : mRenderThread(rt) {}
+
+    virtual void run() {
+        mRenderThread->dispatchFrameCallbacks();
+    }
+};
+
+RenderThread::RenderThread() : Thread(true), Singleton<RenderThread>()
+        , mNextWakeup(LLONG_MAX)
+        , mDisplayEventReceiver(0)
+        , mVsyncRequested(false)
+        , mFrameCallbackTaskPending(false)
+        , mFrameCallbackTask(0) {
+    mFrameCallbackTask = new DispatchFrameCallbacks(this);
+    mLooper = new Looper(false);
+    run("RenderThread");
+}
+
+RenderThread::~RenderThread() {
+}
+
+void RenderThread::initializeDisplayEventReceiver() {
+    LOG_ALWAYS_FATAL_IF(mDisplayEventReceiver, "Initializing a second DisplayEventReceiver?");
+    mDisplayEventReceiver = new DisplayEventReceiver();
+    status_t status = mDisplayEventReceiver->initCheck();
+    LOG_ALWAYS_FATAL_IF(status != NO_ERROR, "Initialization of DisplayEventReceiver "
+            "failed with status: %d", status);
+
+    // Register the FD
+    mLooper->addFd(mDisplayEventReceiver->getFd(), 0,
+            Looper::EVENT_INPUT, RenderThread::displayEventReceiverCallback, this);
+}
+
+int RenderThread::displayEventReceiverCallback(int fd, int events, void* data) {
+    if (events & (Looper::EVENT_ERROR | Looper::EVENT_HANGUP)) {
+        ALOGE("Display event receiver pipe was closed or an error occurred.  "
+                "events=0x%x", events);
+        return 0; // remove the callback
+    }
+
+    if (!(events & Looper::EVENT_INPUT)) {
+        ALOGW("Received spurious callback for unhandled poll event.  "
+                "events=0x%x", events);
+        return 1; // keep the callback
+    }
+
+    reinterpret_cast<RenderThread*>(data)->drainDisplayEventQueue();
+
+    return 1; // keep the callback
+}
+
+static nsecs_t latestVsyncEvent(DisplayEventReceiver* receiver) {
+    DisplayEventReceiver::Event buf[EVENT_BUFFER_SIZE];
+    nsecs_t latest = 0;
+    ssize_t n;
+    while ((n = receiver->getEvents(buf, EVENT_BUFFER_SIZE)) > 0) {
+        for (ssize_t i = 0; i < n; i++) {
+            const DisplayEventReceiver::Event& ev = buf[i];
+            switch (ev.header.type) {
+            case DisplayEventReceiver::DISPLAY_EVENT_VSYNC:
+                latest = ev.header.timestamp;
+                break;
+            }
+        }
+    }
+    if (n < 0) {
+        ALOGW("Failed to get events from display event receiver, status=%d", status_t(n));
+    }
+    return latest;
+}
+
+void RenderThread::drainDisplayEventQueue(bool skipCallbacks) {
+    ATRACE_CALL();
+    nsecs_t vsyncEvent = latestVsyncEvent(mDisplayEventReceiver);
+    if (vsyncEvent > 0) {
+        mVsyncRequested = false;
+        mTimeLord.vsyncReceived(vsyncEvent);
+        if (!skipCallbacks && !mFrameCallbackTaskPending) {
+            ATRACE_NAME("queue mFrameCallbackTask");
+            mFrameCallbackTaskPending = true;
+            queueDelayed(mFrameCallbackTask, DISPATCH_FRAME_CALLBACKS_DELAY);
+        }
+    }
+}
+
+void RenderThread::dispatchFrameCallbacks() {
+    ATRACE_CALL();
+    mFrameCallbackTaskPending = false;
+
+    std::set<IFrameCallback*> callbacks;
+    mFrameCallbacks.swap(callbacks);
+
+    for (std::set<IFrameCallback*>::iterator it = callbacks.begin(); it != callbacks.end(); it++) {
+        (*it)->doFrame();
+    }
+}
+
+void RenderThread::requestVsync() {
+    if (!mVsyncRequested) {
+        mVsyncRequested = true;
+        status_t status = mDisplayEventReceiver->requestNextVsync();
+        LOG_ALWAYS_FATAL_IF(status != NO_ERROR,
+                "requestNextVsync failed with status: %d", status);
+    }
+}
+
+bool RenderThread::threadLoop() {
+    initializeDisplayEventReceiver();
+
+    int timeoutMillis = -1;
+    for (;;) {
+        int result = mLooper->pollOnce(timeoutMillis);
+        LOG_ALWAYS_FATAL_IF(result == Looper::POLL_ERROR,
+                "RenderThread Looper POLL_ERROR!");
+
+        nsecs_t nextWakeup;
+        // Process our queue, if we have anything
+        while (RenderTask* task = nextTask(&nextWakeup)) {
+            task->run();
+            // task may have deleted itself, do not reference it again
+        }
+        if (nextWakeup == LLONG_MAX) {
+            timeoutMillis = -1;
+        } else {
+            nsecs_t timeoutNanos = nextWakeup - systemTime(SYSTEM_TIME_MONOTONIC);
+            timeoutMillis = nanoseconds_to_milliseconds(timeoutNanos);
+            if (timeoutMillis < 0) {
+                timeoutMillis = 0;
+            }
+        }
+
+        if (mPendingRegistrationFrameCallbacks.size() && !mFrameCallbackTaskPending) {
+            drainDisplayEventQueue(true);
+            mFrameCallbacks.insert(
+                    mPendingRegistrationFrameCallbacks.begin(), mPendingRegistrationFrameCallbacks.end());
+            mPendingRegistrationFrameCallbacks.clear();
+            requestVsync();
+        }
+    }
+
+    return false;
+}
+
+void RenderThread::queue(RenderTask* task) {
+    AutoMutex _lock(mLock);
+    mQueue.queue(task);
+    if (mNextWakeup && task->mRunAt < mNextWakeup) {
+        mNextWakeup = 0;
+        mLooper->wake();
+    }
+}
+
+void RenderThread::queueAtFront(RenderTask* task) {
+    AutoMutex _lock(mLock);
+    mQueue.queueAtFront(task);
+    mLooper->wake();
+}
+
+void RenderThread::queueDelayed(RenderTask* task, int delayMs) {
+    nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+    task->mRunAt = now + milliseconds_to_nanoseconds(delayMs);
+    queue(task);
+}
+
+void RenderThread::remove(RenderTask* task) {
+    AutoMutex _lock(mLock);
+    mQueue.remove(task);
+}
+
+void RenderThread::postFrameCallback(IFrameCallback* callback) {
+    mPendingRegistrationFrameCallbacks.insert(callback);
+}
+
+void RenderThread::removeFrameCallback(IFrameCallback* callback) {
+    mFrameCallbacks.erase(callback);
+    mPendingRegistrationFrameCallbacks.erase(callback);
+}
+
+void RenderThread::pushBackFrameCallback(IFrameCallback* callback) {
+    if (mFrameCallbacks.erase(callback)) {
+        mPendingRegistrationFrameCallbacks.insert(callback);
+    }
+}
+
+RenderTask* RenderThread::nextTask(nsecs_t* nextWakeup) {
+    AutoMutex _lock(mLock);
+    RenderTask* next = mQueue.peek();
+    if (!next) {
+        mNextWakeup = LLONG_MAX;
+    } else {
+        mNextWakeup = next->mRunAt;
+        // Most tasks won't be delayed, so avoid unnecessary systemTime() calls
+        if (next->mRunAt <= 0 || next->mRunAt <= systemTime(SYSTEM_TIME_MONOTONIC)) {
+            next = mQueue.next();
+        } else {
+            next = 0;
+        }
+    }
+    if (nextWakeup) {
+        *nextWakeup = mNextWakeup;
+    }
+    return next;
+}
+
+} /* namespace renderthread */
+} /* namespace uirenderer */
+} /* namespace android */