Refactor histogram_macros.h. This improves documentation for the macros in the file, moves LOCAL_* …

base/metrics/histogram_macros_local.h

Index: base/metrics/histogram_macros_local.h
diff --git a/base/metrics/histogram_macros_local.h b/base/metrics/histogram_macros_local.h
new file mode 100644
index 0000000000000000000000000000000000000000..7571a9c4ad2a57c9eef1dcfdc9e5e0b01c117c14
--- /dev/null
+++ b/base/metrics/histogram_macros_local.h
@@ -0,0 +1,88 @@
+// Copyright 2016 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_HISTOGRAM_MACROS_LOCAL_H_
+#define BASE_METRICS_HISTOGRAM_MACROS_LOCAL_H_
+
+#include "base/logging.h"
+#include "base/metrics/histogram.h"
+#include "base/metrics/histogram_macros_internal.h"
+#include "base/time/time.h"
+
+// TODO(rkaplow): Migrate all LOCAL_* usage within Chromium to include this
+// file instead of the histogram_macros.h file.
+
+//------------------------------------------------------------------------------
+// Enumeration histograms.
+//
+// For usage details, see the equivalents in histogram_macros.h.
+
+#define LOCAL_HISTOGRAM_ENUMERATION(name, sample, enum_max)                    \
+   INTERNAL_HISTOGRAM_ENUMERATION_WITH_FLAG(                                   \
+        name, sample, enum_max,                                                \
+        base::HistogramBase::kNoFlags)
+
+#define LOCAL_HISTOGRAM_BOOLEAN(name, sample)                                  \
+    STATIC_HISTOGRAM_POINTER_BLOCK(name, AddBoolean(sample),                   \
+        base::BooleanHistogram::FactoryGet(name, base::Histogram::kNoFlags))
+
+//------------------------------------------------------------------------------
+// Percentage histograms.
+//
+// For usage details, see the equivalents in histogram_macros.h
+
+#define LOCAL_HISTOGRAM_PERCENTAGE(name, under_one_hundred)                    \
+    LOCAL_HISTOGRAM_ENUMERATION(name, under_one_hundred, 101)
+
+//------------------------------------------------------------------------------

[Mark P, 2016/09/26 23:06:47]

optional: I suggest the counts section should go first (as you had it
originally).

comment withdrawn: I see Alexei and I disagree, and I don't feel strongly.

[rkaplow, 2016/09/27 15:08:26]

Ok - I don't personally care much, so will leave as is.

+// Count histograms. These are used for collecting numeric data. Note that we
+// have macros for more specialized use cases below (memory, time, percentages).
+// For usage details, see the equivalents in histogram_macros.h.
+
+#define LOCAL_HISTOGRAM_COUNTS_100(name, sample)                               \
+    LOCAL_HISTOGRAM_CUSTOM_COUNTS(name, sample, 1, 100, 50)
+
+#define LOCAL_HISTOGRAM_COUNTS_10000(name, sample)                             \
+    LOCAL_HISTOGRAM_CUSTOM_COUNTS(name, sample, 1, 10000, 50)
+
+#define LOCAL_HISTOGRAM_COUNTS_1000000(name, sample)                           \
+    LOCAL_HISTOGRAM_CUSTOM_COUNTS(name, sample, 1, 1000000, 50)
+
+#define LOCAL_HISTOGRAM_CUSTOM_COUNTS(name, sample, min, max, bucket_count)    \
+    INTERNAL_HISTOGRAM_CUSTOM_COUNTS_WITH_FLAG(                                \
+        name, sample, min, max, bucket_count, base::HistogramBase::kNoFlags)
+
+//------------------------------------------------------------------------------
+// Timing histograms. These are used for collecting timing data (generally
+// latencies).
+//
+// For usage details, see the equivalents in histogram_macros.h.
+
+#define LOCAL_HISTOGRAM_TIMES(name, sample) LOCAL_HISTOGRAM_CUSTOM_TIMES(      \
+    name, sample, base::TimeDelta::FromMilliseconds(1),                        \
+    base::TimeDelta::FromSeconds(10), 50)
+
+#define LOCAL_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::HistogramBase::kNoFlags))
+
+//------------------------------------------------------------------------------
+// Memory histograms.
+//
+// For usage details, see the equivalents in histogram_macros.h.
+
+#define LOCAL_HISTOGRAM_MEMORY_KB(name, sample) LOCAL_HISTOGRAM_CUSTOM_COUNTS( \
+    name, sample, 1000, 500000, 50)
+
+//------------------------------------------------------------------------------
+// Deprecated histograms. Not recommended for current use.
+
+// TODO(rkaplow): See if we can clean up this macro and usage.
+// Legacy non-explicit version. We suggest using LOCAL_HISTOGRAM_COUNTS_1000000
+// instead.
+#define LOCAL_HISTOGRAM_COUNTS(name, sample)                                   \
+    LOCAL_HISTOGRAM_CUSTOM_COUNTS(name, sample, 1, 1000000, 50)
+
+#endif  // BASE_METRICS_HISTOGRAM_MACROS_LOCAL_H_