Skeleton code of SparseHistogram

Review URL: https://chromiumcodereview.appspot.com/10830156

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@150736 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 193 insertions, 47 deletions

diff --git a/base/metrics/histogram.cc b/base/metrics/histogram.cc
index cea6d0c..ca2e4d9 100644
--- a/base/metrics/histogram.cc
+++ b/base/metrics/histogram.cc
@@ -133,7 +133,7 @@ Histogram* Histogram::FactoryGet(const string& name,
                                  Sample minimum,
                                  Sample maximum,
                                  size_t bucket_count,
-                                 Flags flags) {
+                                 int32 flags) {
   bool valid_arguments =
       InspectConstructionArguments(name, &minimum, &maximum, &bucket_count);
   DCHECK(valid_arguments);
@@ -162,7 +162,7 @@ Histogram* Histogram::FactoryTimeGet(const string& name,
                                      TimeDelta minimum,
                                      TimeDelta maximum,
                                      size_t bucket_count,
-                                     Flags flags) {
+                                     int32 flags) {
   return FactoryGet(name, minimum.InMilliseconds(), maximum.InMilliseconds(),
                     bucket_count, flags);
 }
@@ -442,7 +442,6 @@ Histogram::Histogram(const string& name,
     declared_min_(minimum),
     declared_max_(maximum),
     bucket_count_(bucket_count),
-    flags_(kNoFlags),
     sample_(bucket_count) {}
 
 Histogram::~Histogram() {
@@ -531,7 +530,7 @@ double Histogram::GetBucketSize(Count current, size_t i) const {
 
 const string Histogram::GetAsciiBucketRange(size_t i) const {
   string result;
-  if (kHexRangePrintingFlag & flags_)
+  if (kHexRangePrintingFlag & flags())
     StringAppendF(&result, "%#x", ranges(i));
   else
     StringAppendF(&result, "%d", ranges(i));
@@ -636,8 +635,8 @@ void Histogram::WriteAsciiHeader(const SampleSet& snapshot,
 
     StringAppendF(output, ", average = %.1f", average);
   }
-  if (flags_ & ~kHexRangePrintingFlag)
-    StringAppendF(output, " (flags = 0x%x)", flags_ & ~kHexRangePrintingFlag);
+  if (flags() & ~kHexRangePrintingFlag)
+    StringAppendF(output, " (flags = 0x%x)", flags() & ~kHexRangePrintingFlag);
 }
 
 void Histogram::WriteAsciiBucketContext(const int64 past,
@@ -685,7 +684,7 @@ Histogram* LinearHistogram::FactoryGet(const string& name,
                                        Sample minimum,
                                        Sample maximum,
                                        size_t bucket_count,
-                                       Flags flags) {
+                                       int32 flags) {
   bool valid_arguments = Histogram::InspectConstructionArguments(
       name, &minimum, &maximum, &bucket_count);
   DCHECK(valid_arguments);
@@ -715,7 +714,7 @@ Histogram* LinearHistogram::FactoryTimeGet(const string& name,
                                            TimeDelta minimum,
                                            TimeDelta maximum,
                                            size_t bucket_count,
-                                           Flags flags) {
+                                           int32 flags) {
   return FactoryGet(name, minimum.InMilliseconds(), maximum.InMilliseconds(),
                     bucket_count, flags);
 }
@@ -781,7 +780,7 @@ void LinearHistogram::InitializeBucketRanges(Sample minimum,
 // This section provides implementation for BooleanHistogram.
 //------------------------------------------------------------------------------
 
-Histogram* BooleanHistogram::FactoryGet(const string& name, Flags flags) {
+Histogram* BooleanHistogram::FactoryGet(const string& name, int32 flags) {
   Histogram* histogram = StatisticsRecorder::FindHistogram(name);
   if (!histogram) {
     // To avoid racy destruction at shutdown, the following will be leaked.
@@ -819,7 +818,7 @@ BooleanHistogram::BooleanHistogram(const string& name,
 
 Histogram* CustomHistogram::FactoryGet(const string& name,
                                        const vector<Sample>& custom_ranges,
-                                       Flags flags) {
+                                       int32 flags) {
   CHECK(ValidateCustomRanges(custom_ranges));
 
   Histogram* histogram = StatisticsRecorder::FindHistogram(name);
diff --git a/base/metrics/histogram.h b/base/metrics/histogram.h
index a969dcfa..6320db6 100644
--- a/base/metrics/histogram.h
+++ b/base/metrics/histogram.h
@@ -64,6 +64,7 @@
 
 #include "base/atomicops.h"
 #include "base/base_export.h"
+#include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/logging.h"
@@ -108,7 +109,7 @@ class Lock;
       // histogram.  FactoryGet includes locks on a global histogram name map
       // and is completely thread safe.
       histogram_pointer = base::Histogram::FactoryGet(
-          name, min, max, bucket_count, base::Histogram::kNoFlags);
+          name, min, max, bucket_count, base::HistogramBase::kNoFlags);
 
       // Use Release_Store to ensure that the histogram data is made available
       // globally before we make the pointer visible.
@@ -171,7 +172,7 @@ class Lock;
 #define HISTOGRAM_CUSTOM_COUNTS(name, sample, min, max, bucket_count) \
     STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
         base::Histogram::FactoryGet(name, min, max, bucket_count, \
-                                    base::Histogram::kNoFlags))
+                                    base::HistogramBase::kNoFlags))
 
 #define HISTOGRAM_PERCENTAGE(name, under_one_hundred) \
     HISTOGRAM_ENUMERATION(name, under_one_hundred, 101)
@@ -181,7 +182,7 @@ class Lock;
 #define HISTOGRAM_CUSTOM_TIMES(name, sample, min, max, bucket_count) \
     STATIC_HISTOGRAM_POINTER_BLOCK(name, AddTime(sample), \
         base::Histogram::FactoryTimeGet(name, min, max, bucket_count, \
-                                        base::Histogram::kNoFlags))
+                                        base::HistogramBase::kNoFlags))
 
 // Support histograming of an enumerated value.  The samples should always be
 // strictly less than |boundary_value| -- this prevents you from running into
@@ -192,7 +193,7 @@ class Lock;
 #define HISTOGRAM_ENUMERATION(name, sample, boundary_value) \
     STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
         base::LinearHistogram::FactoryGet(name, 1, boundary_value, \
-            boundary_value + 1, base::Histogram::kNoFlags))
+            boundary_value + 1, base::HistogramBase::kNoFlags))
 
 // Support histograming of an enumerated value. Samples should be one of the
 // std::vector<int> list provided via |custom_ranges|. See comments above
@@ -202,7 +203,7 @@ class Lock;
 #define HISTOGRAM_CUSTOM_ENUMERATION(name, sample, custom_ranges) \
     STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
         base::CustomHistogram::FactoryGet(name, custom_ranges, \
-                                          base::Histogram::kNoFlags))
+                                          base::HistogramBase::kNoFlags))
 
 //------------------------------------------------------------------------------
 // Define Debug vs non-debug flavors of macros.
@@ -366,20 +367,6 @@ class BASE_EXPORT Histogram : public HistogramBase {
     CUSTOM,
   };
 
-  enum Flags {
-    kNoFlags = 0,
-    kUmaTargetedHistogramFlag = 0x1,  // Histogram should be UMA uploaded.
-
-    // Indicate that the histogram was pickled to be sent across an IPC Channel.
-    // If we observe this flag on a histogram being aggregated into after IPC,
-    // then we are running in a single process mode, and the aggregation should
-    // not take place (as we would be aggregating back into the source
-    // histogram!).
-    kIPCSerializationSourceFlag = 0x10,
-
-    kHexRangePrintingFlag = 0x8000,  // Fancy bucket-naming supported.
-  };
-
   enum Inconsistencies {
     NO_INCONSISTENCIES = 0x0,
     RANGE_CHECKSUM_ERROR = 0x1,
@@ -460,12 +447,12 @@ class BASE_EXPORT Histogram : public HistogramBase {
                                Sample minimum,
                                Sample maximum,
                                size_t bucket_count,
-                               Flags flags);
+                               int32 flags);
   static Histogram* FactoryTimeGet(const std::string& name,
                                    base::TimeDelta minimum,
                                    base::TimeDelta maximum,
                                    size_t bucket_count,
-                                   Flags flags);
+                                   int32 flags);
 
   // Time call for use with DHISTOGRAM*.
   // Returns TimeTicks::Now() in debug and TimeTicks() in release build.
@@ -495,13 +482,6 @@ class BASE_EXPORT Histogram : public HistogramBase {
   virtual void WriteHTMLGraph(std::string* output) const OVERRIDE;
   virtual void WriteAscii(std::string* output) const OVERRIDE;
 
-  // Support generic flagging of Histograms.
-  // 0x1 Currently used to mark this histogram to be recorded by UMA..
-  // 0x8000 means print ranges in hex.
-  void SetFlags(Flags flags) { flags_ = static_cast<Flags> (flags_ | flags); }
-  void ClearFlags(Flags flags) { flags_ = static_cast<Flags>(flags_ & ~flags); }
-  int flags() const { return flags_; }
-
   // Convenience methods for serializing/deserializing the histograms.
   // Histograms from Renderer process are serialized and sent to the browser.
   // Browser process reconstructs the histogram from the pickled version
@@ -638,9 +618,6 @@ class BASE_EXPORT Histogram : public HistogramBase {
   Sample declared_max_;  // Over this goes into counts_[bucket_count_ - 1].
   size_t bucket_count_;  // Dimension of counts_[].
 
-  // Flag the histogram for recording by UMA via metric_services.h.
-  Flags flags_;
-
   // Finally, provide the state that changes with the addition of each new
   // sample.
   SampleSet sample_;
@@ -662,12 +639,12 @@ class BASE_EXPORT LinearHistogram : public Histogram {
                                Sample minimum,
                                Sample maximum,
                                size_t bucket_count,
-                               Flags flags);
+                               int32 flags);
   static Histogram* FactoryTimeGet(const std::string& name,
                                    TimeDelta minimum,
                                    TimeDelta maximum,
                                    size_t bucket_count,
-                                   Flags flags);
+                                   int32 flags);
 
   static void InitializeBucketRanges(Sample minimum,
                                      Sample maximum,
@@ -714,7 +691,7 @@ class BASE_EXPORT LinearHistogram : public Histogram {
 // BooleanHistogram is a histogram for booleans.
 class BASE_EXPORT BooleanHistogram : public LinearHistogram {
  public:
-  static Histogram* FactoryGet(const std::string& name, Flags flags);
+  static Histogram* FactoryGet(const std::string& name, int32 flags);
 
   virtual ClassType histogram_type() const OVERRIDE;
 
@@ -737,7 +714,7 @@ class BASE_EXPORT CustomHistogram : public Histogram {
   // client should not depend on this.
   static Histogram* FactoryGet(const std::string& name,
                                const std::vector<Sample>& custom_ranges,
-                               Flags flags);
+                               int32 flags);
 
   // Overridden from Histogram:
   virtual ClassType histogram_type() const OVERRIDE;
diff --git a/base/metrics/histogram_base.cc b/base/metrics/histogram_base.cc
index 42d793e..6032a35 100644
--- a/base/metrics/histogram_base.cc
+++ b/base/metrics/histogram_base.cc
@@ -4,13 +4,24 @@
 
 #include "base/metrics/histogram_base.h"
 
+#include <climits>
+
 namespace base {
 
 const HistogramBase::Sample HistogramBase::kSampleType_MAX = INT_MAX;
 
 HistogramBase::HistogramBase(const std::string& name)
-    : histogram_name_(name) {}
+    : histogram_name_(name),
+      flags_(kNoFlags) {}
 
 HistogramBase::~HistogramBase() {}
 
+void HistogramBase::SetFlags(int32 flags) {
+  flags_ |= flags;
+}
+
+void HistogramBase::ClearFlags(int32 flags) {
+  flags_ &= ~flags;
+}
+
 }  // namespace base
diff --git a/base/metrics/histogram_base.h b/base/metrics/histogram_base.h
index d8c2910..caa0a4c 100644
--- a/base/metrics/histogram_base.h
+++ b/base/metrics/histogram_base.h
@@ -5,10 +5,10 @@
 #ifndef BASE_METRICS_HISTOGRAM_BASE_H_
 #define BASE_METRICS_HISTOGRAM_BASE_H_
 
-#include <climits>
 #include <string>
 
 #include "base/base_export.h"
+#include "base/basictypes.h"
 
 namespace base {
 
@@ -19,11 +19,32 @@ class BASE_EXPORT HistogramBase {
 
   static const Sample kSampleType_MAX;  // INT_MAX
 
+  enum Flags {
+    kNoFlags = 0,
+    kUmaTargetedHistogramFlag = 0x1,  // Histogram should be UMA uploaded.
+
+    // Indicate that the histogram was pickled to be sent across an IPC Channel.
+    // If we observe this flag on a histogram being aggregated into after IPC,
+    // then we are running in a single process mode, and the aggregation should
+    // not take place (as we would be aggregating back into the source
+    // histogram!).
+    kIPCSerializationSourceFlag = 0x10,
+
+    // Only for Histogram and its sub classes: fancy bucket-naming support.
+    kHexRangePrintingFlag = 0x8000,
+  };
+
+
   HistogramBase(const std::string& name);
   virtual ~HistogramBase();
 
   std::string histogram_name() const { return histogram_name_; }
 
+  // Operations with Flags enum.
+  int32 flags() const { return flags_; }
+  void SetFlags(int32 flags);
+  void ClearFlags(int32 flags);
+
   virtual void Add(Sample value) = 0;
 
   // The following methods provide graphical histogram displays.
@@ -32,6 +53,9 @@ class BASE_EXPORT HistogramBase {
 
  private:
   const std::string histogram_name_;
+  int32 flags_;
+
+  DISALLOW_COPY_AND_ASSIGN(HistogramBase);
 };
 
 }  // namespace base
diff --git a/base/metrics/sparse_histogram.cc b/base/metrics/sparse_histogram.cc
new file mode 100644
index 0000000..05a68b5
--- /dev/null
+++ b/base/metrics/sparse_histogram.cc
@@ -0,0 +1,45 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/metrics/sparse_histogram.h"
+
+#include "base/metrics/statistics_recorder.h"
+
+using std::string;
+
+namespace base {
+
+// static
+HistogramBase* SparseHistogram::FactoryGet(const string& name,
+                                           int32 flags) {
+  // TODO(kaiwang): Register and get SparseHistogram with StatisticsRecorder.
+  HistogramBase* histogram = new SparseHistogram(name);
+  histogram->SetFlags(flags);
+  return histogram;
+}
+
+SparseHistogram::~SparseHistogram() {}
+
+void SparseHistogram::Add(Sample value) {
+  base::AutoLock auto_lock(lock_);
+  samples_[value]++;
+}
+
+void SparseHistogram::SnapshotSample(std::map<Sample, Count>* samples) const {
+  base::AutoLock auto_lock(lock_);
+  *samples = samples_;
+}
+
+void SparseHistogram::WriteHTMLGraph(string* output) const {
+  // TODO(kaiwang): Implement.
+}
+
+void SparseHistogram::WriteAscii(string* output) const {
+  // TODO(kaiwang): Implement.
+}
+
+SparseHistogram::SparseHistogram(const string& name)
+    : HistogramBase(name) {}
+
+}  // namespace base
diff --git a/base/metrics/sparse_histogram.h b/base/metrics/sparse_histogram.h
new file mode 100644
index 0000000..9ef435e
--- /dev/null
+++ b/base/metrics/sparse_histogram.h
@@ -0,0 +1,50 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_METRICS_SPARSE_HISTOGRAM_H_
+#define BASE_METRICS_SPARSE_HISTOGRAM_H_
+
+#include <map>
+#include <string>
+
+#include "base/base_export.h"
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/metrics/histogram_base.h"
+#include "base/synchronization/lock.h"
+
+namespace base {
+
+class BASE_EXPORT_PRIVATE SparseHistogram : public HistogramBase {
+ public:
+  // If there's one with same name, return the existing one. If not, create a
+  // new one.
+  static HistogramBase* FactoryGet(const std::string& name, int32 flags);
+
+  virtual ~SparseHistogram();
+
+  virtual void Add(Sample value) OVERRIDE;
+
+  virtual void SnapshotSample(std::map<Sample, Count>* sample) const;
+  virtual void WriteHTMLGraph(std::string* output) const OVERRIDE;
+  virtual void WriteAscii(std::string* output) const OVERRIDE;
+
+ protected:
+  // Clients should always use FactoryGet to create SparseHistogram.
+  SparseHistogram(const std::string& name);
+
+ private:
+  friend class SparseHistogramTest;  // For constuctor calling.
+
+  std::map<Sample, Count> samples_;
+
+  // Protects access to above map.
+  mutable base::Lock lock_;
+
+  DISALLOW_COPY_AND_ASSIGN(SparseHistogram);
+};
+
+}  // namespace base
+
+#endif  // BASE_METRICS_SPARSE_HISTOGRAM_H_
diff --git a/base/metrics/sparse_histogram_unittest.cc b/base/metrics/sparse_histogram_unittest.cc
new file mode 100644
index 0000000..1ed0e71
--- /dev/null
+++ b/base/metrics/sparse_histogram_unittest.cc
@@ -0,0 +1,40 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <string>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/metrics/sparse_histogram.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace base {
+
+class SparseHistogramTest : public testing::Test {
+ protected:
+  scoped_ptr<SparseHistogram> NewSparseHistogram(const std::string& name) {
+    return scoped_ptr<SparseHistogram>(new SparseHistogram(name));
+  }
+};
+
+TEST_F(SparseHistogramTest, BasicTest) {
+  scoped_ptr<SparseHistogram> histogram(NewSparseHistogram("Sparse1"));
+  std::map<HistogramBase::Sample, HistogramBase::Count> sample;
+  histogram->SnapshotSample(&sample);
+
+  ASSERT_EQ(0u, sample.size());
+
+  histogram->Add(100);
+  histogram->SnapshotSample(&sample);
+  ASSERT_EQ(1u, sample.size());
+  EXPECT_EQ(1, sample[100]);
+
+  histogram->Add(100);
+  histogram->Add(101);
+  histogram->SnapshotSample(&sample);
+  ASSERT_EQ(2u, sample.size());
+  EXPECT_EQ(2, sample[100]);
+  EXPECT_EQ(1, sample[101]);
+}
+
+}  // namespace base