Update from chromium https://crrev.com/304586
Review URL: https://codereview.chromium.org/732423002
diff --git a/base/metrics/histogram_macros.h b/base/metrics/histogram_macros.h
new file mode 100644
index 0000000..a9996d1
--- /dev/null
+++ b/base/metrics/histogram_macros.h
@@ -0,0 +1,232 @@
+// Copyright 2014 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_H_
+#define BASE_METRICS_HISTOGRAM_MACROS_H_
+
+#include "base/atomicops.h"
+#include "base/basictypes.h"
+#include "base/logging.h"
+#include "base/metrics/histogram.h"
+#include "base/time/time.h"
+
+//------------------------------------------------------------------------------
+// Histograms are often put in areas where they are called many many times, and
+// performance is critical. As a result, they are designed to have a very low
+// recurring cost of executing (adding additional samples). Toward that end,
+// the macros declare a static pointer to the histogram in question, and only
+// take a "slow path" to construct (or find) the histogram on the first run
+// through the macro. We leak the histograms at shutdown time so that we don't
+// have to validate using the pointers at any time during the running of the
+// process.
+
+// The following code is generally what a thread-safe static pointer
+// initialization looks like for a histogram (after a macro is expanded). This
+// sample is an expansion (with comments) of the code for
+// LOCAL_HISTOGRAM_CUSTOM_COUNTS().
+
+/*
+ do {
+ // The pointer's presence indicates the initialization is complete.
+ // Initialization is idempotent, so it can safely be atomically repeated.
+ static base::subtle::AtomicWord atomic_histogram_pointer = 0;
+
+ // Acquire_Load() ensures that we acquire visibility to the pointed-to data
+ // in the histogram.
+ base::Histogram* histogram_pointer(reinterpret_cast<base::Histogram*>(
+ base::subtle::Acquire_Load(&atomic_histogram_pointer)));
+
+ if (!histogram_pointer) {
+ // This is the slow path, which will construct OR find the matching
+ // 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::HistogramBase::kNoFlags);
+
+ // Use Release_Store to ensure that the histogram data is made available
+ // globally before we make the pointer visible.
+ // Several threads may perform this store, but the same value will be
+ // stored in all cases (for a given named/spec'ed histogram).
+ // We could do this without any barrier, since FactoryGet entered and
+ // exited a lock after construction, but this barrier makes things clear.
+ base::subtle::Release_Store(&atomic_histogram_pointer,
+ reinterpret_cast<base::subtle::AtomicWord>(histogram_pointer));
+ }
+
+ // Ensure calling contract is upheld, and the name does NOT vary.
+ DCHECK(histogram_pointer->histogram_name() == constant_histogram_name);
+
+ histogram_pointer->Add(sample);
+ } while (0);
+*/
+
+// The above pattern is repeated in several macros. The only elements that
+// vary are the invocation of the Add(sample) vs AddTime(sample), and the choice
+// of which FactoryGet method to use. The different FactoryGet methods have
+// various argument lists, so the function with its argument list is provided as
+// a macro argument here. The name is only used in a DCHECK, to assure that
+// callers don't try to vary the name of the histogram (which would tend to be
+// ignored by the one-time initialization of the histogtram_pointer).
+#define STATIC_HISTOGRAM_POINTER_BLOCK(constant_histogram_name, \
+ histogram_add_method_invocation, \
+ histogram_factory_get_invocation) \
+ do { \
+ static base::subtle::AtomicWord atomic_histogram_pointer = 0; \
+ base::HistogramBase* histogram_pointer( \
+ reinterpret_cast<base::HistogramBase*>( \
+ base::subtle::Acquire_Load(&atomic_histogram_pointer))); \
+ if (!histogram_pointer) { \
+ histogram_pointer = histogram_factory_get_invocation; \
+ base::subtle::Release_Store(&atomic_histogram_pointer, \
+ reinterpret_cast<base::subtle::AtomicWord>(histogram_pointer)); \
+ } \
+ if (DCHECK_IS_ON) \
+ histogram_pointer->CheckName(constant_histogram_name); \
+ histogram_pointer->histogram_add_method_invocation; \
+ } while (0)
+
+
+//------------------------------------------------------------------------------
+// Provide easy general purpose histogram in a macro, just like stats counters.
+// The first four macros use 50 buckets.
+
+#define LOCAL_HISTOGRAM_TIMES(name, sample) LOCAL_HISTOGRAM_CUSTOM_TIMES( \
+ name, sample, base::TimeDelta::FromMilliseconds(1), \
+ base::TimeDelta::FromSeconds(10), 50)
+
+// For folks that need real specific times, use this to select a precise range
+// of times you want plotted, and the number of buckets you want used.
+#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))
+
+#define LOCAL_HISTOGRAM_COUNTS(name, sample) LOCAL_HISTOGRAM_CUSTOM_COUNTS( \
+ name, sample, 1, 1000000, 50)
+
+#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_CUSTOM_COUNTS(name, sample, min, max, bucket_count) \
+ STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
+ base::Histogram::FactoryGet(name, min, max, bucket_count, \
+ base::HistogramBase::kNoFlags))
+
+// This is a helper macro used by other macros and shouldn't be used directly.
+#define HISTOGRAM_ENUMERATION_WITH_FLAG(name, sample, boundary, flag) \
+ STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
+ base::LinearHistogram::FactoryGet(name, 1, boundary, boundary + 1, \
+ flag))
+
+#define LOCAL_HISTOGRAM_PERCENTAGE(name, under_one_hundred) \
+ LOCAL_HISTOGRAM_ENUMERATION(name, under_one_hundred, 101)
+
+#define LOCAL_HISTOGRAM_BOOLEAN(name, sample) \
+ STATIC_HISTOGRAM_POINTER_BLOCK(name, AddBoolean(sample), \
+ base::BooleanHistogram::FactoryGet(name, base::Histogram::kNoFlags))
+
+// Support histograming of an enumerated value. The samples should always be
+// strictly less than |boundary_value| -- this prevents you from running into
+// problems down the line if you add additional buckets to the histogram. Note
+// also that, despite explicitly setting the minimum bucket value to |1| below,
+// it is fine for enumerated histograms to be 0-indexed -- this is because
+// enumerated histograms should never have underflow.
+#define LOCAL_HISTOGRAM_ENUMERATION(name, sample, boundary_value) \
+ STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
+ base::LinearHistogram::FactoryGet(name, 1, boundary_value, \
+ 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
+// CustomRanges::FactoryGet about the requirement of |custom_ranges|.
+// You can use the helper function CustomHistogram::ArrayToCustomRanges to
+// transform a C-style array of valid sample values to a std::vector<int>.
+#define LOCAL_HISTOGRAM_CUSTOM_ENUMERATION(name, sample, custom_ranges) \
+ STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
+ base::CustomHistogram::FactoryGet(name, custom_ranges, \
+ base::HistogramBase::kNoFlags))
+
+#define LOCAL_HISTOGRAM_MEMORY_KB(name, sample) LOCAL_HISTOGRAM_CUSTOM_COUNTS( \
+ name, sample, 1000, 500000, 50)
+
+//------------------------------------------------------------------------------
+// The following macros provide typical usage scenarios for callers that wish
+// to record histogram data, and have the data submitted/uploaded via UMA.
+// Not all systems support such UMA, but if they do, the following macros
+// should work with the service.
+
+#define UMA_HISTOGRAM_TIMES(name, sample) UMA_HISTOGRAM_CUSTOM_TIMES( \
+ name, sample, base::TimeDelta::FromMilliseconds(1), \
+ base::TimeDelta::FromSeconds(10), 50)
+
+#define UMA_HISTOGRAM_MEDIUM_TIMES(name, sample) UMA_HISTOGRAM_CUSTOM_TIMES( \
+ name, sample, base::TimeDelta::FromMilliseconds(10), \
+ base::TimeDelta::FromMinutes(3), 50)
+
+// Use this macro when times can routinely be much longer than 10 seconds.
+#define UMA_HISTOGRAM_LONG_TIMES(name, sample) UMA_HISTOGRAM_CUSTOM_TIMES( \
+ name, sample, base::TimeDelta::FromMilliseconds(1), \
+ base::TimeDelta::FromHours(1), 50)
+
+// Use this macro when times can routinely be much longer than 10 seconds and
+// you want 100 buckets.
+#define UMA_HISTOGRAM_LONG_TIMES_100(name, sample) UMA_HISTOGRAM_CUSTOM_TIMES( \
+ name, sample, base::TimeDelta::FromMilliseconds(1), \
+ base::TimeDelta::FromHours(1), 100)
+
+#define UMA_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::kUmaTargetedHistogramFlag))
+
+#define UMA_HISTOGRAM_COUNTS(name, sample) UMA_HISTOGRAM_CUSTOM_COUNTS( \
+ name, sample, 1, 1000000, 50)
+
+#define UMA_HISTOGRAM_COUNTS_100(name, sample) UMA_HISTOGRAM_CUSTOM_COUNTS( \
+ name, sample, 1, 100, 50)
+
+#define UMA_HISTOGRAM_COUNTS_10000(name, sample) UMA_HISTOGRAM_CUSTOM_COUNTS( \
+ name, sample, 1, 10000, 50)
+
+#define UMA_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::HistogramBase::kUmaTargetedHistogramFlag))
+
+#define UMA_HISTOGRAM_MEMORY_KB(name, sample) UMA_HISTOGRAM_CUSTOM_COUNTS( \
+ name, sample, 1000, 500000, 50)
+
+#define UMA_HISTOGRAM_MEMORY_MB(name, sample) UMA_HISTOGRAM_CUSTOM_COUNTS( \
+ name, sample, 1, 1000, 50)
+
+#define UMA_HISTOGRAM_PERCENTAGE(name, under_one_hundred) \
+ UMA_HISTOGRAM_ENUMERATION(name, under_one_hundred, 101)
+
+#define UMA_HISTOGRAM_BOOLEAN(name, sample) \
+ STATIC_HISTOGRAM_POINTER_BLOCK(name, AddBoolean(sample), \
+ base::BooleanHistogram::FactoryGet(name, \
+ base::HistogramBase::kUmaTargetedHistogramFlag))
+
+// The samples should always be strictly less than |boundary_value|. For more
+// details, see the comment for the |LOCAL_HISTOGRAM_ENUMERATION| macro, above.
+#define UMA_HISTOGRAM_ENUMERATION(name, sample, boundary_value) \
+ HISTOGRAM_ENUMERATION_WITH_FLAG(name, sample, boundary_value, \
+ base::HistogramBase::kUmaTargetedHistogramFlag)
+
+// Similar to UMA_HISTOGRAM_ENUMERATION, but used for recording stability
+// histograms. Use this if recording a histogram that should be part of the
+// initial stability log.
+#define UMA_STABILITY_HISTOGRAM_ENUMERATION(name, sample, boundary_value) \
+ HISTOGRAM_ENUMERATION_WITH_FLAG(name, sample, boundary_value, \
+ base::HistogramBase::kUmaStabilityHistogramFlag)
+
+#define UMA_HISTOGRAM_CUSTOM_ENUMERATION(name, sample, custom_ranges) \
+ STATIC_HISTOGRAM_POINTER_BLOCK(name, Add(sample), \
+ base::CustomHistogram::FactoryGet(name, custom_ranges, \
+ base::HistogramBase::kUmaTargetedHistogramFlag))
+
+#endif // BASE_METRICS_HISTOGRAM_MACROS_H_
