Add linearly spaced counting histograms

webrtc/system_wrappers/include/metrics.h

 //
 // Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 //
 // Use of this source code is governed by a BSD-style license
 // that can be found in the LICENSE file in the root of the source
 // tree. An additional intellectual property rights grant can be found
 // in the file PATENTS.  All contributing project authors may
 // be found in the AUTHORS file in the root of the source tree.
 //
 
@@ skipping 67 matching lines @@
 #define RTC_HISTOGRAM_COUNTS_10000(name, sample) \
   RTC_HISTOGRAM_COUNTS(name, sample, 1, 10000, 50)
 
 #define RTC_HISTOGRAM_COUNTS_100000(name, sample) \
   RTC_HISTOGRAM_COUNTS(name, sample, 1, 100000, 50)
 
 #define RTC_HISTOGRAM_COUNTS(name, sample, min, max, bucket_count) \
   RTC_HISTOGRAM_COMMON_BLOCK(name, sample, \
       webrtc::metrics::HistogramFactoryGetCounts(name, min, max, bucket_count))
 
+#define RTC_HISTOGRAM_COUNTS_LINEAR(name, sample, min, max, bucket_count)      \
+  RTC_HISTOGRAM_COMMON_BLOCK(name, sample,                                     \
+                             webrtc::metrics::HistogramFactoryGetCountsLinear( \
+                                 name, min, max, bucket_count))
+
 // Deprecated.
 // TODO(asapersson): Remove.
 #define RTC_HISTOGRAM_COUNTS_SPARSE_100(name, sample) \
   RTC_HISTOGRAM_COUNTS_SPARSE(name, sample, 1, 100, 50)
 
 #define RTC_HISTOGRAM_COUNTS_SPARSE(name, sample, min, max, bucket_count) \
   RTC_HISTOGRAM_COMMON_BLOCK_SLOW(name, sample, \
       webrtc::metrics::HistogramFactoryGetCounts(name, min, max, bucket_count))
 
 // Histogram for percentage (evenly spaced buckets).
@@ skipping 108 matching lines @@
 
 class Histogram;
 
 // Functions for getting pointer to histogram (constructs or finds the named
 // histogram).
 
 // Get histogram for counters.
 Histogram* HistogramFactoryGetCounts(
     const std::string& name, int min, int max, int bucket_count);
 
+// Get histogram for counters with linear bucket spacing.
+Histogram* HistogramFactoryGetCountsLinear(const std::string& name,
+                                           int min,
+                                           int max,
+                                           int bucket_count);
+
 // Get histogram for enumerators.
 // |boundary| should be above the max enumerator sample.
 Histogram* HistogramFactoryGetEnumeration(
     const std::string& name, int boundary);
 
 // Returns name of the histogram.
 const std::string& GetHistogramName(Histogram* histogram_pointer);
 
 // Function for adding a |sample| to a histogram.
 void HistogramAdd(Histogram* histogram_pointer, int sample);
 
 }  // namespace metrics
 }  // namespace webrtc
 
 #endif  // WEBRTC_SYSTEM_WRAPPERS_INCLUDE_METRICS_H_