1 /*
2 * Copyright (C) 2017 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 #define LOG_TAG "CameraLatencyHistogram"
18 #include <inttypes.h>
19 #include <android-base/stringprintf.h>
20 #include <utils/Log.h>
21 #include <camera/StringUtils.h>
22
23 #include "LatencyHistogram.h"
24
25 namespace android {
26
CameraLatencyHistogram(int32_t binSizeMs,int32_t binCount)27 CameraLatencyHistogram::CameraLatencyHistogram(int32_t binSizeMs, int32_t binCount) :
28 mBinSizeMs(binSizeMs),
29 mBinCount(binCount),
30 mBins(binCount),
31 mTotalCount(0) {
32 }
33
add(nsecs_t start,nsecs_t end)34 void CameraLatencyHistogram::add(nsecs_t start, nsecs_t end) {
35 nsecs_t duration = end - start;
36 int32_t durationMs = static_cast<int32_t>(duration / 1000000LL);
37 int32_t binIndex = durationMs / mBinSizeMs;
38
39 if (binIndex < 0) {
40 binIndex = 0;
41 } else if (binIndex >= mBinCount) {
42 binIndex = mBinCount-1;
43 }
44
45 mBins[binIndex]++;
46 mTotalCount++;
47 }
48
reset()49 void CameraLatencyHistogram::reset() {
50 memset(mBins.data(), 0, mBins.size() * sizeof(int64_t));
51 mTotalCount = 0;
52 }
53
dump(int fd,const char * name) const54 void CameraLatencyHistogram::dump(int fd, const char* name) const {
55 if (mTotalCount == 0) {
56 return;
57 }
58
59 std::string lines;
60 lines += fmt::sprintf("%s (%" PRId64 ") samples\n", name, mTotalCount);
61
62 std::string lineBins, lineBinCounts;
63 formatHistogramText(lineBins, lineBinCounts);
64
65 lineBins += ("\n");
66 lineBinCounts += ("\n");
67 lines += lineBins;
68 lines += lineBinCounts;
69
70 write(fd, lines.c_str(), lines.size());
71 }
72
log(const char * fmt,...)73 void CameraLatencyHistogram::log(const char* fmt, ...) {
74 if (mTotalCount == 0) {
75 return;
76 }
77
78 va_list args;
79 va_start(args, fmt);
80 std::string histogramName;
81 base::StringAppendV(&histogramName, fmt, args);
82 ALOGI("%s (%" PRId64 ") samples:", histogramName.c_str(), mTotalCount);
83 va_end(args);
84
85 std::string lineBins, lineBinCounts;
86 formatHistogramText(lineBins, lineBinCounts);
87
88 ALOGI("%s", lineBins.c_str());
89 ALOGI("%s", lineBinCounts.c_str());
90 }
91
formatHistogramText(std::string & lineBins,std::string & lineBinCounts) const92 void CameraLatencyHistogram::formatHistogramText(
93 std::string& lineBins, std::string& lineBinCounts) const {
94 lineBins = " ";
95 lineBinCounts = " ";
96
97 for (int32_t i = 0; i < mBinCount; i++) {
98 if (i == mBinCount - 1) {
99 lineBins += " inf (max ms)";
100 } else {
101 lineBins += fmt::sprintf("%7d", mBinSizeMs*(i+1));
102 }
103 lineBinCounts += fmt::sprintf(" %02.2f", 100.0*mBins[i]/mTotalCount);
104 }
105 lineBinCounts += " (%)";
106 }
107
108 }; //namespace android
109