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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "mozilla/layout/LayoutTelemetryTools.h"
#include "MainThreadUtils.h"
#include "mozilla/EnumeratedArray.h"
#include "mozilla/EnumeratedRange.h"
#include "mozilla/Telemetry.h"
namespace mozilla::layout_telemetry {
using LayoutSubsystemDurations =
EnumeratedArray<LayoutSubsystem, double, size_t(LayoutSubsystem::Count)>;
struct PerTickData {
constexpr PerTickData() = default;
LayoutSubsystemDurations mLayoutSubsystemDurationMs{0.0, 0.0, 0.0,
0.0, 0.0, 0.0};
};
static PerTickData sData;
static AutoRecord* sCurrentRecord;
// Returns the key name expected by telemetry. Keep to date with
// toolkits/components/telemetry/Histograms.json.
static nsLiteralCString SubsystemTelemetryKey(LayoutSubsystem aSubsystem) {
switch (aSubsystem) {
default:
MOZ_CRASH("Unexpected LayoutSubsystem value");
case LayoutSubsystem::Restyle:
return "Restyle"_ns;
case LayoutSubsystem::Reflow:
return "ReflowOther"_ns;
case LayoutSubsystem::ReflowFlex:
return "ReflowFlex"_ns;
case LayoutSubsystem::ReflowGrid:
return "ReflowGrid"_ns;
case LayoutSubsystem::ReflowTable:
return "ReflowTable"_ns;
case LayoutSubsystem::ReflowText:
return "ReflowText"_ns;
}
}
void PingPerTickTelemetry() {
auto range =
MakeEnumeratedRange(LayoutSubsystem::Restyle, LayoutSubsystem::Count);
for (auto subsystem : range) {
auto key = SubsystemTelemetryKey(subsystem);
double& duration = sData.mLayoutSubsystemDurationMs[subsystem];
if (duration > 0.0) {
Telemetry::Accumulate(Telemetry::PRESSHELL_LAYOUT_TOTAL_MS_PER_TICK, key,
static_cast<uint32_t>(duration));
duration = 0.0;
}
}
}
AutoRecord::AutoRecord(LayoutSubsystem aSubsystem)
: mParentRecord(sCurrentRecord), mSubsystem(aSubsystem) {
MOZ_ASSERT(NS_IsMainThread());
// If we're re-entering the same subsystem, don't update the current record.
if (mParentRecord && mParentRecord->mSubsystem == mSubsystem) {
return;
}
mStartTime = TimeStamp::Now();
if (mParentRecord) {
// If we're entering a new subsystem, record the amount of time spent in the
// parent record before setting the new current record.
mParentRecord->mDurationMs +=
(mStartTime - mParentRecord->mStartTime).ToMilliseconds();
}
sCurrentRecord = this;
}
AutoRecord::~AutoRecord() {
if (sCurrentRecord != this) {
// If this record is not head of the list, do nothing.
return;
}
TimeStamp now = TimeStamp::Now();
mDurationMs += (now - mStartTime).ToMilliseconds();
sData.mLayoutSubsystemDurationMs[mSubsystem] += mDurationMs;
if (mParentRecord) {
// Restart the parent recording from this point
mParentRecord->mStartTime = now;
}
// Unlink this record from the current record list
sCurrentRecord = mParentRecord;
}
} // namespace mozilla::layout_telemetry