Home | History | Annotate | Download | only in gui 
      1 /*
      2  * Copyright 2016 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 #undef LOG_TAG
     18 #define LOG_TAG "OccupancyTracker"
     19 
     20 #include <gui/OccupancyTracker.h>
     21 #include <binder/Parcel.h>
     22 #include <utils/String8.h>
     23 #include <utils/Trace.h>
     24 
     25 #include <inttypes.h>
     26 
     27 namespace android {
     28 
     29 status_t OccupancyTracker::Segment::writeToParcel(Parcel* parcel) const {
     30     status_t result = parcel->writeInt64(totalTime);
     31     if (result != OK) {
     32         return result;
     33     }
     34     result = parcel->writeUint64(static_cast<uint64_t>(numFrames));
     35     if (result != OK) {
     36         return result;
     37     }
     38     result = parcel->writeFloat(occupancyAverage);
     39     if (result != OK) {
     40         return result;
     41     }
     42     return parcel->writeBool(usedThirdBuffer);
     43 }
     44 
     45 status_t OccupancyTracker::Segment::readFromParcel(const Parcel* parcel) {
     46     status_t result = parcel->readInt64(&totalTime);
     47     if (result != OK) {
     48         return result;
     49     }
     50     uint64_t uintNumFrames = 0;
     51     result = parcel->readUint64(&uintNumFrames);
     52     if (result != OK) {
     53         return result;
     54     }
     55     numFrames = static_cast<size_t>(uintNumFrames);
     56     result = parcel->readFloat(&occupancyAverage);
     57     if (result != OK) {
     58         return result;
     59     }
     60     return parcel->readBool(&usedThirdBuffer);
     61 }
     62 
     63 void OccupancyTracker::registerOccupancyChange(size_t occupancy) {
     64     ATRACE_CALL();
     65     nsecs_t now = systemTime();
     66     nsecs_t delta = now - mLastOccupancyChangeTime;
     67     if (delta > NEW_SEGMENT_DELAY) {
     68         recordPendingSegment();
     69     } else {
     70         mPendingSegment.totalTime += delta;
     71         if (mPendingSegment.mOccupancyTimes.count(mLastOccupancy)) {
     72             mPendingSegment.mOccupancyTimes[mLastOccupancy] += delta;
     73         } else {
     74             mPendingSegment.mOccupancyTimes[mLastOccupancy] = delta;
     75         }
     76     }
     77     if (occupancy > mLastOccupancy) {
     78         ++mPendingSegment.numFrames;
     79     }
     80     mLastOccupancyChangeTime = now;
     81     mLastOccupancy = occupancy;
     82 }
     83 
     84 std::vector<OccupancyTracker::Segment> OccupancyTracker::getSegmentHistory(
     85         bool forceFlush) {
     86     if (forceFlush) {
     87         recordPendingSegment();
     88     }
     89     std::vector<Segment> segments(mSegmentHistory.cbegin(),
     90             mSegmentHistory.cend());
     91     mSegmentHistory.clear();
     92     return segments;
     93 }
     94 
     95 void OccupancyTracker::recordPendingSegment() {
     96     // Only record longer segments to get a better measurement of actual double-
     97     // vs. triple-buffered time
     98     if (mPendingSegment.numFrames > LONG_SEGMENT_THRESHOLD) {
     99         float occupancyAverage = 0.0f;
    100         bool usedThirdBuffer = false;
    101         for (const auto& timePair : mPendingSegment.mOccupancyTimes) {
    102             size_t occupancy = timePair.first;
    103             float timeRatio = static_cast<float>(timePair.second) /
    104                     mPendingSegment.totalTime;
    105             occupancyAverage += timeRatio * occupancy;
    106             usedThirdBuffer = usedThirdBuffer || (occupancy > 1);
    107         }
    108         mSegmentHistory.push_front({mPendingSegment.totalTime,
    109                 mPendingSegment.numFrames, occupancyAverage, usedThirdBuffer});
    110         if (mSegmentHistory.size() > MAX_HISTORY_SIZE) {
    111             mSegmentHistory.pop_back();
    112         }
    113     }
    114     mPendingSegment.clear();
    115 }
    116 
    117 } // namespace android
    118