base/android/record_histogram.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/android/record_histogram.h"
   6
   7 #include <map>
   8
   9 #include "base/android/jni_android.h"
  10 #include "base/android/jni_string.h"
  11 #include "base/lazy_instance.h"
  12 #include "base/metrics/histogram.h"
  13 #include "base/metrics/statistics_recorder.h"
  14 #include "base/synchronization/lock.h"
  15 #include "base/time/time.h"
  16 #include "jni/RecordHistogram_jni.h"
  17
  18 namespace base {
  19 namespace android {
  20 namespace {
  21
  22 // Simple thread-safe wrapper for caching histograms. This avoids
  23 // relatively expensive JNI string translation for each recording.
  24 class HistogramCache {
  25  public:
  26   HistogramCache() {}
  27
  28   HistogramBase* BooleanHistogram(JNIEnv* env,
  29                                   jstring j_histogram_name,
  30                                   jint j_histogram_key) {
  31     DCHECK(j_histogram_name);
  32     DCHECK(j_histogram_key);
  33     HistogramBase* histogram = FindLocked(j_histogram_key);
  34     if (histogram)
  35       return histogram;
  36
  37     std::string histogram_name = ConvertJavaStringToUTF8(env, j_histogram_name);
  38     histogram = BooleanHistogram::FactoryGet(
  39         histogram_name, HistogramBase::kUmaTargetedHistogramFlag);
  40     return InsertLocked(j_histogram_key, histogram);
  41   }
  42
  43   HistogramBase* EnumeratedHistogram(JNIEnv* env,
  44                                      jstring j_histogram_name,
  45                                      jint j_histogram_key,
  46                                      jint j_boundary) {
  47     DCHECK(j_histogram_name);
  48     DCHECK(j_histogram_key);
  49     HistogramBase* histogram = FindLocked(j_histogram_key);
  50     int boundary = static_cast<int>(j_boundary);
  51     if (histogram) {
  52       DCHECK(histogram->HasConstructionArguments(1, boundary, boundary + 1));
  53       return histogram;
  54     }
  55
  56     std::string histogram_name = ConvertJavaStringToUTF8(env, j_histogram_name);
  57     histogram =
  58         LinearHistogram::FactoryGet(histogram_name, 1, boundary, boundary + 1,
  59                                     HistogramBase::kUmaTargetedHistogramFlag);
  60     return InsertLocked(j_histogram_key, histogram);
  61   }
  62
  63   HistogramBase* CustomTimesHistogram(JNIEnv* env,
  64                                       jstring j_histogram_name,
  65                                       jint j_histogram_key,
  66                                       jlong j_min,
  67                                       jlong j_max,
  68                                       jint j_bucket_count) {
  69     DCHECK(j_histogram_name);
  70     DCHECK(j_histogram_key);
  71     HistogramBase* histogram = FindLocked(j_histogram_key);
  72     int64 min = static_cast<int64>(j_min);
  73     int64 max = static_cast<int64>(j_max);
  74     int bucket_count = static_cast<int>(j_bucket_count);
  75     if (histogram) {
  76       DCHECK(histogram->HasConstructionArguments(min, max, bucket_count));
  77       return histogram;
  78     }
  79
  80     std::string histogram_name = ConvertJavaStringToUTF8(env, j_histogram_name);
  81     // This intentionally uses FactoryGet and not FactoryTimeGet. FactoryTimeGet
  82     // is just a convenience for constructing the underlying Histogram with
  83     // TimeDelta arguments.
  84     histogram = Histogram::FactoryGet(histogram_name, min, max, bucket_count,
  85                                       HistogramBase::kUmaTargetedHistogramFlag);
  86     return InsertLocked(j_histogram_key, histogram);
  87   }
  88
  89  private:
  90   HistogramBase* FindLocked(jint j_histogram_key) {
  91     base::AutoLock locked(lock_);
  92     auto histogram_it = histograms_.find(j_histogram_key);
  93     return histogram_it != histograms_.end() ? histogram_it->second : nullptr;
  94   }
  95
  96   HistogramBase* InsertLocked(jint j_histogram_key, HistogramBase* histogram) {
  97     base::AutoLock locked(lock_);
  98     histograms_.insert(std::make_pair(j_histogram_key, histogram));
  99     return histogram;
 100   }
 101
 102   base::Lock lock_;
 103   std::map<jint, HistogramBase*> histograms_;
 104
 105   DISALLOW_COPY_AND_ASSIGN(HistogramCache);
 106 };
 107
 108 base::LazyInstance<HistogramCache>::Leaky g_histograms;
 109
 110 }  // namespace
 111
 112 void RecordBooleanHistogram(JNIEnv* env,
 113                             jclass clazz,
 114                             jstring j_histogram_name,
 115                             jint j_histogram_key,
 116                             jboolean j_sample) {
 117   bool sample = static_cast<bool>(j_sample);
 118   g_histograms.Get()
 119       .BooleanHistogram(env, j_histogram_name, j_histogram_key)
 120       ->AddBoolean(sample);
 121 }
 122
 123 void RecordEnumeratedHistogram(JNIEnv* env,
 124                                jclass clazz,
 125                                jstring j_histogram_name,
 126                                jint j_histogram_key,
 127                                jint j_sample,
 128                                jint j_boundary) {
 129   int sample = static_cast<int>(j_sample);
 130
 131   g_histograms.Get()
 132       .EnumeratedHistogram(env, j_histogram_name, j_histogram_key, j_boundary)
 133       ->Add(sample);
 134 }
 135
 136 void RecordCustomTimesHistogramMilliseconds(JNIEnv* env,
 137                                             jclass clazz,
 138                                             jstring j_histogram_name,
 139                                             jint j_histogram_key,
 140                                             jlong j_duration,
 141                                             jlong j_min,
 142                                             jlong j_max,
 143                                             jint j_num_buckets) {
 144   g_histograms.Get()
 145       .CustomTimesHistogram(env, j_histogram_name, j_histogram_key, j_min,
 146                             j_max, j_num_buckets)
 147       ->AddTime(TimeDelta::FromMilliseconds(static_cast<int64>(j_duration)));
 148 }
 149
 150 void Initialize(JNIEnv* env, jclass) {
 151   StatisticsRecorder::Initialize();
 152 }
 153
 154 // This backs a Java test util for testing histograms -
 155 // MetricsUtils.HistogramDelta. It should live in a test-specific file, but we
 156 // currently can't have test-specific native code packaged in test-specific Java
 157 // targets - see http://crbug.com/415945.
 158 jint GetHistogramValueCountForTesting(JNIEnv* env,
 159                                       jclass clazz,
 160                                       jstring histogram_name,
 161                                       jint sample) {
 162   HistogramBase* histogram = StatisticsRecorder::FindHistogram(
 163       android::ConvertJavaStringToUTF8(env, histogram_name));
 164   if (histogram == nullptr) {
 165     // No samples have been recorded for this histogram (yet?).
 166     return 0;
 167   }
 168
 169   scoped_ptr<HistogramSamples> samples = histogram->SnapshotSamples();
 170   return samples->GetCount(static_cast<int>(sample));
 171 }
 172
 173 bool RegisterRecordHistogram(JNIEnv* env) {
 174   return RegisterNativesImpl(env);
 175 }
 176
 177 }  // namespace android
 178 }  // namespace base