blob: 591f704bf41155e4105bcef8a6e7e900fa720aec [file] [log] [blame]
// Copyright 2015 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 "cc/base/histograms.h"
#include <stdint.h>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <limits>
#include "base/lazy_instance.h"
#include "base/logging.h"
#include "base/numerics/safe_conversions.h"
#include "base/synchronization/lock.h"
namespace cc {
// Global data tracking the client name that was set.
// Both of these variables are protected by the lock.
static base::LazyInstance<base::Lock>::Leaky g_client_name_lock =
static const char* g_client_name = nullptr;
static bool g_multiple_client_names_set = false;
void SetClientNameForMetrics(const char* client_name) {
base::AutoLock auto_lock(g_client_name_lock.Get());
// Only warn once.
if (g_multiple_client_names_set)
// If a different name is set, return nullptr from now on and log a warning.
const char* old_client_name = g_client_name;
if (old_client_name && strcmp(old_client_name, client_name)) {
g_client_name = nullptr;
g_multiple_client_names_set = true;
LOG(WARNING) << "Started multiple compositor clients (" << old_client_name
<< ", " << client_name
<< ") in one process. Some metrics will be disabled.";
// If the client name is being set for the first time, store it.
if (!old_client_name)
g_client_name = client_name;
const char* GetClientNameForMetrics() {
base::AutoLock auto_lock(g_client_name_lock.Get());
return g_client_name;
// Minimum elapsed time of 1us to limit weighting of fast calls.
static const int64_t kMinimumTimeMicroseconds = 1;
ScopedUMAHistogramAreaTimerBase::ScopedUMAHistogramAreaTimerBase() : area_(0) {
ScopedUMAHistogramAreaTimerBase::~ScopedUMAHistogramAreaTimerBase() = default;
bool ScopedUMAHistogramAreaTimerBase::GetHistogramValues(
Sample* time_microseconds,
Sample* pixels_per_ms) const {
return GetHistogramValues(
timer_.Elapsed(), area_.ValueOrDefault(std::numeric_limits<int>::max()),
time_microseconds, pixels_per_ms);
// static
bool ScopedUMAHistogramAreaTimerBase::GetHistogramValues(
base::TimeDelta elapsed,
int area,
Sample* time_microseconds,
Sample* pixels_per_ms) {
elapsed = std::max(
elapsed, base::TimeDelta::FromMicroseconds(kMinimumTimeMicroseconds));
double area_per_time = area / elapsed.InMillisecondsF();
// It is not clear how NaN can get here, but we've gotten crashes from
// saturated_cast.
if (std::isnan(area_per_time))
return false;
*time_microseconds = base::saturated_cast<Sample>(elapsed.InMicroseconds());
*pixels_per_ms = base::saturated_cast<Sample>(area_per_time);
return true;
} // namespace cc