gecko/mobile/android/base/gfx/PanningPerfAPI.java
Chris Lord 98d6ecce87 Bug 819310 - Fix possible race when stopping checkerboard recording. r=kats
Make stopCheckerboardRecording safe to call while recordCheckerboard is
executing.
2012-12-07 15:11:05 +00:00

118 lines
4.2 KiB
Java

/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
package org.mozilla.gecko.gfx;
import android.os.SystemClock;
import android.util.Log;
import java.util.ArrayList;
import java.util.List;
public class PanningPerfAPI {
private static final String LOGTAG = "GeckoPanningPerfAPI";
// make this large enough to avoid having to resize the frame time
// list, as that may be expensive and impact the thing we're trying
// to measure.
private static final int EXPECTED_FRAME_COUNT = 2048;
private static boolean mRecordingFrames = false;
private static List<Long> mFrameTimes;
private static long mFrameStartTime;
private static boolean mRecordingCheckerboard = false;
private static List<Float> mCheckerboardAmounts;
private static long mCheckerboardStartTime;
private static void initialiseRecordingArrays() {
if (mFrameTimes == null) {
mFrameTimes = new ArrayList<Long>(EXPECTED_FRAME_COUNT);
} else {
mFrameTimes.clear();
}
if (mCheckerboardAmounts == null) {
mCheckerboardAmounts = new ArrayList<Float>(EXPECTED_FRAME_COUNT);
} else {
mCheckerboardAmounts.clear();
}
}
public static void startFrameTimeRecording() {
if (mRecordingFrames || mRecordingCheckerboard) {
Log.e(LOGTAG, "Error: startFrameTimeRecording() called while already recording!");
return;
}
mRecordingFrames = true;
initialiseRecordingArrays();
mFrameStartTime = SystemClock.uptimeMillis();
}
public static List<Long> stopFrameTimeRecording() {
if (!mRecordingFrames) {
Log.e(LOGTAG, "Error: stopFrameTimeRecording() called when not recording!");
return null;
}
mRecordingFrames = false;
return mFrameTimes;
}
public static void recordFrameTime() {
// this will be called often, so try to make it as quick as possible
if (mRecordingFrames) {
mFrameTimes.add(SystemClock.uptimeMillis() - mFrameStartTime);
}
}
public static boolean isRecordingCheckerboard() {
return mRecordingCheckerboard;
}
public static void startCheckerboardRecording() {
if (mRecordingCheckerboard || mRecordingFrames) {
Log.e(LOGTAG, "Error: startCheckerboardRecording() called while already recording!");
return;
}
mRecordingCheckerboard = true;
initialiseRecordingArrays();
mCheckerboardStartTime = SystemClock.uptimeMillis();
}
public static List<Float> stopCheckerboardRecording() {
if (!mRecordingCheckerboard) {
Log.e(LOGTAG, "Error: stopCheckerboardRecording() called when not recording!");
return null;
}
mRecordingCheckerboard = false;
// We take the number of values in mCheckerboardAmounts here, as there's
// the possibility that this function is called while recordCheckerboard
// is still executing. As values are added to this list last, we use
// this number as the canonical number of recordings.
int values = mCheckerboardAmounts.size();
// The score will be the sum of all the values in mCheckerboardAmounts,
// so weight the checkerboard values by time so that frame-rate and
// run-length don't affect score.
long lastTime = 0;
float totalTime = mFrameTimes.get(values - 1);
for (int i = 0; i < values; i++) {
long elapsedTime = mFrameTimes.get(i) - lastTime;
mCheckerboardAmounts.set(i, mCheckerboardAmounts.get(i) * elapsedTime / totalTime);
lastTime += elapsedTime;
}
return mCheckerboardAmounts;
}
public static void recordCheckerboard(float amount) {
// this will be called often, so try to make it as quick as possible
if (mRecordingCheckerboard) {
mFrameTimes.add(SystemClock.uptimeMillis() - mCheckerboardStartTime);
mCheckerboardAmounts.add(amount);
}
}
}