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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 "TelemetryIOInterposeObserver.h"
#include "core/TelemetryCommon.h"
#include "js/Array.h" // JS::NewArrayObject
#include "js/PropertyAndElement.h" // JS_DefineUCProperty
#include "js/PropertyDescriptor.h" // JSPROP_ENUMERATE, JSPROP_READONLY
#include "js/ValueArray.h"
#include "nsIFile.h"
namespace mozilla::Telemetry {
TelemetryIOInterposeObserver::TelemetryIOInterposeObserver(nsIFile* aXreDir)
: mCurStage(STAGE_STARTUP) {
nsAutoString xreDirPath;
nsresult rv = aXreDir->GetPath(xreDirPath);
if (NS_SUCCEEDED(rv)) {
AddPath(xreDirPath, u"{xre}"_ns);
}
}
void TelemetryIOInterposeObserver::AddPath(const nsAString& aPath,
const nsAString& aSubstName) {
mSafeDirs.AppendElement(SafeDir(aPath, aSubstName));
}
// Threshold for reporting slow main-thread I/O (50 milliseconds).
const TimeDuration kTelemetryReportThreshold =
TimeDuration::FromMilliseconds(50);
void TelemetryIOInterposeObserver::Observe(Observation& aOb) {
// We only report main-thread I/O
if (!IsMainThread()) {
return;
}
if (aOb.ObservedOperation() == OpNextStage) {
mCurStage = NextStage(mCurStage);
MOZ_ASSERT(mCurStage < NUM_STAGES);
return;
}
if (aOb.Duration() < kTelemetryReportThreshold) {
return;
}
// Get the filename
nsAutoString filename;
aOb.Filename(filename);
// Discard observations without filename
if (filename.IsEmpty()) {
return;
}
#if defined(XP_WIN)
auto comparator = nsCaseInsensitiveStringComparator;
#else
auto comparator = nsTDefaultStringComparator<char16_t>;
#endif
nsAutoString processedName;
uint32_t safeDirsLen = mSafeDirs.Length();
for (uint32_t i = 0; i < safeDirsLen; ++i) {
if (StringBeginsWith(filename, mSafeDirs[i].mPath, comparator)) {
processedName = mSafeDirs[i].mSubstName;
processedName += Substring(filename, mSafeDirs[i].mPath.Length());
break;
}
}
if (processedName.IsEmpty()) {
return;
}
// Create a new entry or retrieve the existing one
FileIOEntryType* entry = mFileStats.PutEntry(processedName);
if (entry) {
FileStats& stats = entry->GetModifiableData()->mStats[mCurStage];
// Update the statistics
stats.totalTime += (double)aOb.Duration().ToMilliseconds();
switch (aOb.ObservedOperation()) {
case OpCreateOrOpen:
stats.creates++;
break;
case OpRead:
stats.reads++;
break;
case OpWrite:
stats.writes++;
break;
case OpFSync:
stats.fsyncs++;
break;
case OpStat:
stats.stats++;
break;
default:
break;
}
}
}
bool TelemetryIOInterposeObserver::ReflectFileStats(FileIOEntryType* entry,
JSContext* cx,
JS::Handle<JSObject*> obj) {
JS::RootedValueArray<NUM_STAGES> stages(cx);
FileStatsByStage& statsByStage = *entry->GetModifiableData();
for (int s = STAGE_STARTUP; s < NUM_STAGES; ++s) {
FileStats& fileStats = statsByStage.mStats[s];
if (fileStats.totalTime == 0 && fileStats.creates == 0 &&
fileStats.reads == 0 && fileStats.writes == 0 &&
fileStats.fsyncs == 0 && fileStats.stats == 0) {
// Don't add an array that contains no information
stages[s].setNull();
continue;
}
// Array we want to report
JS::RootedValueArray<6> stats(cx);
stats[0].setNumber(fileStats.totalTime);
stats[1].setNumber(fileStats.creates);
stats[2].setNumber(fileStats.reads);
stats[3].setNumber(fileStats.writes);
stats[4].setNumber(fileStats.fsyncs);
stats[5].setNumber(fileStats.stats);
// Create jsStats as array of elements above
JS::Rooted<JSObject*> jsStats(cx, JS::NewArrayObject(cx, stats));
if (!jsStats) {
continue;
}
stages[s].setObject(*jsStats);
}
JS::Rooted<JSObject*> jsEntry(cx, JS::NewArrayObject(cx, stages));
if (!jsEntry) {
return false;
}
// Add jsEntry to top-level dictionary
const nsAString& key = entry->GetKey();
return JS_DefineUCProperty(cx, obj, key.Data(), key.Length(), jsEntry,
JSPROP_ENUMERATE | JSPROP_READONLY);
}
bool TelemetryIOInterposeObserver::ReflectIntoJS(
JSContext* cx, JS::Handle<JSObject*> rootObj) {
return mFileStats.ReflectIntoJS(ReflectFileStats, cx, rootObj);
}
/**
* Get size of hash table with file stats
*/
size_t TelemetryIOInterposeObserver::SizeOfIncludingThis(
mozilla::MallocSizeOf aMallocSizeOf) const {
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
size_t TelemetryIOInterposeObserver::SizeOfExcludingThis(
mozilla::MallocSizeOf aMallocSizeOf) const {
size_t size = 0;
size += mFileStats.ShallowSizeOfExcludingThis(aMallocSizeOf);
for (auto iter = mFileStats.ConstIter(); !iter.Done(); iter.Next()) {
size += iter.Get()->GetKey().SizeOfExcludingThisIfUnshared(aMallocSizeOf);
}
size += mSafeDirs.ShallowSizeOfExcludingThis(aMallocSizeOf);
uint32_t safeDirsLen = mSafeDirs.Length();
for (uint32_t i = 0; i < safeDirsLen; ++i) {
size += mSafeDirs[i].SizeOfExcludingThis(aMallocSizeOf);
}
return size;
}
} // namespace mozilla::Telemetry