gecko-dev/dom/base/nsWindowMemoryReporter.cpp
Nicholas Nethercote 63ee27b690 Bug 1192128 - In DOM memory reporter, handle WindowID() being a uint64_t. r=mccr8.
--HG--
extra : rebase_source : 0166b09f8800c8ee2509643573e8f85f01d0b3c0
2015-08-06 22:09:30 -07:00

936 lines
32 KiB
C++

/* -*- 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "amIAddonManager.h"
#include "nsWindowMemoryReporter.h"
#include "nsGlobalWindow.h"
#include "nsIDocument.h"
#include "nsIDOMWindowCollection.h"
#include "nsIEffectiveTLDService.h"
#include "mozilla/ClearOnShutdown.h"
#include "mozilla/Preferences.h"
#include "mozilla/Services.h"
#include "mozilla/StaticPtr.h"
#include "nsNetCID.h"
#include "nsPrintfCString.h"
#include "XPCJSMemoryReporter.h"
#include "js/MemoryMetrics.h"
#include "nsServiceManagerUtils.h"
using namespace mozilla;
StaticRefPtr<nsWindowMemoryReporter> sWindowReporter;
/**
* Don't trigger a ghost window check when a DOM window is detached if we've
* run it this recently.
*/
const int32_t kTimeBetweenChecks = 45; /* seconds */
nsWindowMemoryReporter::nsWindowMemoryReporter()
: mLastCheckForGhostWindows(TimeStamp::NowLoRes()),
mCycleCollectorIsRunning(false),
mCheckTimerWaitingForCCEnd(false)
{
}
nsWindowMemoryReporter::~nsWindowMemoryReporter()
{
KillCheckTimer();
}
NS_IMPL_ISUPPORTS(nsWindowMemoryReporter, nsIMemoryReporter, nsIObserver,
nsISupportsWeakReference)
static nsresult
AddNonJSSizeOfWindowAndItsDescendents(nsGlobalWindow* aWindow,
nsTabSizes* aSizes)
{
// Measure the window.
nsWindowSizes windowSizes(moz_malloc_size_of);
aWindow->AddSizeOfIncludingThis(&windowSizes);
windowSizes.addToTabSizes(aSizes);
// Measure the inner window, if there is one.
nsWindowSizes innerWindowSizes(moz_malloc_size_of);
nsGlobalWindow* inner = aWindow->IsOuterWindow() ? aWindow->GetCurrentInnerWindowInternal()
: nullptr;
if (inner) {
inner->AddSizeOfIncludingThis(&innerWindowSizes);
innerWindowSizes.addToTabSizes(aSizes);
}
nsCOMPtr<nsIDOMWindowCollection> frames;
nsresult rv = aWindow->GetFrames(getter_AddRefs(frames));
NS_ENSURE_SUCCESS(rv, rv);
uint32_t length;
rv = frames->GetLength(&length);
NS_ENSURE_SUCCESS(rv, rv);
// Measure this window's descendents.
for (uint32_t i = 0; i < length; i++) {
nsCOMPtr<nsIDOMWindow> child;
rv = frames->Item(i, getter_AddRefs(child));
NS_ENSURE_SUCCESS(rv, rv);
NS_ENSURE_STATE(child);
nsGlobalWindow* childWin =
static_cast<nsGlobalWindow*>(static_cast<nsIDOMWindow *>(child.get()));
rv = AddNonJSSizeOfWindowAndItsDescendents(childWin, aSizes);
NS_ENSURE_SUCCESS(rv, rv);
}
return NS_OK;
}
static nsresult
NonJSSizeOfTab(nsPIDOMWindow* aWindow, size_t* aDomSize, size_t* aStyleSize, size_t* aOtherSize)
{
nsGlobalWindow* window = static_cast<nsGlobalWindow*>(aWindow);
nsTabSizes sizes;
nsresult rv = AddNonJSSizeOfWindowAndItsDescendents(window, &sizes);
NS_ENSURE_SUCCESS(rv, rv);
*aDomSize = sizes.mDom;
*aStyleSize = sizes.mStyle;
*aOtherSize = sizes.mOther;
return NS_OK;
}
/* static */ void
nsWindowMemoryReporter::Init()
{
MOZ_ASSERT(!sWindowReporter);
sWindowReporter = new nsWindowMemoryReporter();
ClearOnShutdown(&sWindowReporter);
RegisterStrongMemoryReporter(sWindowReporter);
RegisterNonJSSizeOfTab(NonJSSizeOfTab);
nsCOMPtr<nsIObserverService> os = services::GetObserverService();
if (os) {
// DOM_WINDOW_DESTROYED_TOPIC announces what we call window "detachment",
// when a window's docshell is set to nullptr.
os->AddObserver(sWindowReporter, DOM_WINDOW_DESTROYED_TOPIC,
/* weakRef = */ true);
os->AddObserver(sWindowReporter, "after-minimize-memory-usage",
/* weakRef = */ true);
os->AddObserver(sWindowReporter, "cycle-collector-begin",
/* weakRef = */ true);
os->AddObserver(sWindowReporter, "cycle-collector-end",
/* weakRef = */ true);
}
RegisterStrongMemoryReporter(new GhostWindowsReporter());
RegisterGhostWindowsDistinguishedAmount(GhostWindowsReporter::DistinguishedAmount);
}
static already_AddRefed<nsIURI>
GetWindowURI(nsIDOMWindow *aWindow)
{
nsCOMPtr<nsPIDOMWindow> pWindow = do_QueryInterface(aWindow);
NS_ENSURE_TRUE(pWindow, nullptr);
nsCOMPtr<nsIDocument> doc = pWindow->GetExtantDoc();
nsCOMPtr<nsIURI> uri;
if (doc) {
uri = doc->GetDocumentURI();
}
if (!uri) {
nsCOMPtr<nsIScriptObjectPrincipal> scriptObjPrincipal =
do_QueryInterface(aWindow);
NS_ENSURE_TRUE(scriptObjPrincipal, nullptr);
// GetPrincipal() will print a warning if the window does not have an outer
// window, so check here for an outer window first. This code is
// functionally correct if we leave out the GetOuterWindow() check, but we
// end up printing a lot of warnings during debug mochitests.
if (pWindow->GetOuterWindow()) {
nsIPrincipal* principal = scriptObjPrincipal->GetPrincipal();
if (principal) {
principal->GetURI(getter_AddRefs(uri));
}
}
}
return uri.forget();
}
static void
AppendWindowURI(nsGlobalWindow *aWindow, nsACString& aStr, bool aAnonymize)
{
nsCOMPtr<nsIURI> uri = GetWindowURI(aWindow);
if (uri) {
if (aAnonymize && !aWindow->IsChromeWindow()) {
aStr.AppendPrintf("<anonymized-%llu>", aWindow->WindowID());
} else {
nsCString spec;
uri->GetSpec(spec);
// A hack: replace forward slashes with '\\' so they aren't
// treated as path separators. Users of the reporters
// (such as about:memory) have to undo this change.
spec.ReplaceChar('/', '\\');
aStr += spec;
}
} else {
// If we're unable to find a URI, we're dealing with a chrome window with
// no document in it (or somesuch), so we call this a "system window".
aStr += NS_LITERAL_CSTRING("[system]");
}
}
MOZ_DEFINE_MALLOC_SIZE_OF(WindowsMallocSizeOf)
// The key is the window ID.
typedef nsDataHashtable<nsUint64HashKey, nsCString> WindowPaths;
static nsresult
ReportAmount(const nsCString& aBasePath, const char* aPathTail,
size_t aAmount, const nsCString& aDescription,
uint32_t aKind, uint32_t aUnits,
nsIMemoryReporterCallback* aCb,
nsISupports* aClosure)
{
if (aAmount == 0) {
return NS_OK;
}
nsAutoCString path(aBasePath);
path += aPathTail;
return aCb->Callback(EmptyCString(), path, aKind, aUnits,
aAmount, aDescription, aClosure);
}
static nsresult
ReportSize(const nsCString& aBasePath, const char* aPathTail,
size_t aAmount, const nsCString& aDescription,
nsIMemoryReporterCallback* aCb,
nsISupports* aClosure)
{
return ReportAmount(aBasePath, aPathTail, aAmount, aDescription,
nsIMemoryReporter::KIND_HEAP,
nsIMemoryReporter::UNITS_BYTES, aCb, aClosure);
}
static nsresult
ReportCount(const nsCString& aBasePath, const char* aPathTail,
size_t aAmount, const nsCString& aDescription,
nsIMemoryReporterCallback* aCb,
nsISupports* aClosure)
{
return ReportAmount(aBasePath, aPathTail, aAmount, aDescription,
nsIMemoryReporter::KIND_OTHER,
nsIMemoryReporter::UNITS_COUNT, aCb, aClosure);
}
static nsresult
CollectWindowReports(nsGlobalWindow *aWindow,
amIAddonManager *addonManager,
nsWindowSizes *aWindowTotalSizes,
nsTHashtable<nsUint64HashKey> *aGhostWindowIDs,
WindowPaths *aWindowPaths,
WindowPaths *aTopWindowPaths,
nsIMemoryReporterCallback *aCb,
nsISupports *aClosure,
bool aAnonymize)
{
nsAutoCString windowPath("explicit/");
// Avoid calling aWindow->GetTop() if there's no outer window. It will work
// just fine, but will spew a lot of warnings.
nsGlobalWindow *top = nullptr;
nsCOMPtr<nsIURI> location;
if (aWindow->GetOuterWindow()) {
// Our window should have a null top iff it has a null docshell.
MOZ_ASSERT(!!aWindow->GetTop() == !!aWindow->GetDocShell());
top = aWindow->GetTop();
if (top) {
location = GetWindowURI(top);
}
}
if (!location) {
location = GetWindowURI(aWindow);
}
if (addonManager && location) {
bool ok;
nsAutoCString id;
if (NS_SUCCEEDED(addonManager->MapURIToAddonID(location, id, &ok)) && ok) {
// Add-on names are not privacy-sensitive, so we can use them with
// impunity.
windowPath += NS_LITERAL_CSTRING("add-ons/") + id +
NS_LITERAL_CSTRING("/");
}
}
windowPath += NS_LITERAL_CSTRING("window-objects/");
if (top) {
windowPath += NS_LITERAL_CSTRING("top(");
AppendWindowURI(top, windowPath, aAnonymize);
windowPath.AppendPrintf(", id=%llu)", top->WindowID());
aTopWindowPaths->Put(aWindow->WindowID(), windowPath);
windowPath += aWindow->IsFrozen() ? NS_LITERAL_CSTRING("/cached/")
: NS_LITERAL_CSTRING("/active/");
} else {
if (aGhostWindowIDs->Contains(aWindow->WindowID())) {
windowPath += NS_LITERAL_CSTRING("top(none)/ghost/");
} else {
windowPath += NS_LITERAL_CSTRING("top(none)/detached/");
}
}
windowPath += NS_LITERAL_CSTRING("window(");
AppendWindowURI(aWindow, windowPath, aAnonymize);
windowPath += NS_LITERAL_CSTRING(")");
// Use |windowPath|, but replace "explicit/" with "event-counts/".
nsCString censusWindowPath(windowPath);
censusWindowPath.Replace(0, strlen("explicit"), "event-counts");
// Remember the path for later.
aWindowPaths->Put(aWindow->WindowID(), windowPath);
#define REPORT_SIZE(_pathTail, _amount, _desc) \
do { \
nsresult rv = ReportSize(windowPath, _pathTail, _amount, \
NS_LITERAL_CSTRING(_desc), aCb, aClosure); \
NS_ENSURE_SUCCESS(rv, rv); \
} while (0)
#define REPORT_COUNT(_pathTail, _amount, _desc) \
do { \
nsresult rv = ReportCount(censusWindowPath, _pathTail, _amount, \
NS_LITERAL_CSTRING(_desc), aCb, aClosure); \
NS_ENSURE_SUCCESS(rv, rv); \
} while (0)
nsWindowSizes windowSizes(WindowsMallocSizeOf);
aWindow->AddSizeOfIncludingThis(&windowSizes);
REPORT_SIZE("/dom/element-nodes", windowSizes.mDOMElementNodesSize,
"Memory used by the element nodes in a window's DOM.");
aWindowTotalSizes->mDOMElementNodesSize += windowSizes.mDOMElementNodesSize;
REPORT_SIZE("/dom/text-nodes", windowSizes.mDOMTextNodesSize,
"Memory used by the text nodes in a window's DOM.");
aWindowTotalSizes->mDOMTextNodesSize += windowSizes.mDOMTextNodesSize;
REPORT_SIZE("/dom/cdata-nodes", windowSizes.mDOMCDATANodesSize,
"Memory used by the CDATA nodes in a window's DOM.");
aWindowTotalSizes->mDOMCDATANodesSize += windowSizes.mDOMCDATANodesSize;
REPORT_SIZE("/dom/comment-nodes", windowSizes.mDOMCommentNodesSize,
"Memory used by the comment nodes in a window's DOM.");
aWindowTotalSizes->mDOMCommentNodesSize += windowSizes.mDOMCommentNodesSize;
REPORT_SIZE("/dom/event-targets", windowSizes.mDOMEventTargetsSize,
"Memory used by the event targets table in a window's DOM, and "
"the objects it points to, which include XHRs.");
aWindowTotalSizes->mDOMEventTargetsSize += windowSizes.mDOMEventTargetsSize;
REPORT_COUNT("/dom/event-targets", windowSizes.mDOMEventTargetsCount,
"Number of non-node event targets in the event targets table "
"in a window's DOM, such as XHRs.");
aWindowTotalSizes->mDOMEventTargetsCount +=
windowSizes.mDOMEventTargetsCount;
REPORT_COUNT("/dom/event-listeners", windowSizes.mDOMEventListenersCount,
"Number of event listeners in a window, including event "
"listeners on nodes and other event targets.");
aWindowTotalSizes->mDOMEventListenersCount +=
windowSizes.mDOMEventListenersCount;
REPORT_SIZE("/dom/other", windowSizes.mDOMOtherSize,
"Memory used by a window's DOM that isn't measured by the "
"other 'dom/' numbers.");
aWindowTotalSizes->mDOMOtherSize += windowSizes.mDOMOtherSize;
REPORT_SIZE("/property-tables",
windowSizes.mPropertyTablesSize,
"Memory used for the property tables within a window.");
aWindowTotalSizes->mPropertyTablesSize += windowSizes.mPropertyTablesSize;
REPORT_SIZE("/style-sheets", windowSizes.mStyleSheetsSize,
"Memory used by style sheets within a window.");
aWindowTotalSizes->mStyleSheetsSize += windowSizes.mStyleSheetsSize;
REPORT_SIZE("/layout/pres-shell", windowSizes.mLayoutPresShellSize,
"Memory used by layout's PresShell, along with any structures "
"allocated in its arena and not measured elsewhere, "
"within a window.");
aWindowTotalSizes->mLayoutPresShellSize += windowSizes.mLayoutPresShellSize;
REPORT_SIZE("/layout/line-boxes", windowSizes.mArenaStats.mLineBoxes,
"Memory used by line boxes within a window.");
aWindowTotalSizes->mArenaStats.mLineBoxes
+= windowSizes.mArenaStats.mLineBoxes;
REPORT_SIZE("/layout/rule-nodes", windowSizes.mArenaStats.mRuleNodes,
"Memory used by CSS rule nodes within a window.");
aWindowTotalSizes->mArenaStats.mRuleNodes
+= windowSizes.mArenaStats.mRuleNodes;
REPORT_SIZE("/layout/style-contexts", windowSizes.mArenaStats.mStyleContexts,
"Memory used by style contexts within a window.");
aWindowTotalSizes->mArenaStats.mStyleContexts
+= windowSizes.mArenaStats.mStyleContexts;
REPORT_SIZE("/layout/style-structs", windowSizes.mArenaStats.mStyleStructs,
"Memory used by style structs within a window.");
aWindowTotalSizes->mArenaStats.mStyleStructs
+= windowSizes.mArenaStats.mStyleStructs;
REPORT_SIZE("/layout/style-sets", windowSizes.mLayoutStyleSetsSize,
"Memory used by style sets within a window.");
aWindowTotalSizes->mLayoutStyleSetsSize += windowSizes.mLayoutStyleSetsSize;
REPORT_SIZE("/layout/text-runs", windowSizes.mLayoutTextRunsSize,
"Memory used for text-runs (glyph layout) in the PresShell's "
"frame tree, within a window.");
aWindowTotalSizes->mLayoutTextRunsSize += windowSizes.mLayoutTextRunsSize;
REPORT_SIZE("/layout/pres-contexts", windowSizes.mLayoutPresContextSize,
"Memory used for the PresContext in the PresShell's frame "
"within a window.");
aWindowTotalSizes->mLayoutPresContextSize +=
windowSizes.mLayoutPresContextSize;
// There are many different kinds of frames, but it is very likely
// that only a few matter. Implement a cutoff so we don't bloat
// about:memory with many uninteresting entries.
const size_t FRAME_SUNDRIES_THRESHOLD =
js::MemoryReportingSundriesThreshold();
size_t frameSundriesSize = 0;
#define FRAME_ID(classname) \
{ \
size_t frameSize \
= windowSizes.mArenaStats.FRAME_ID_STAT_FIELD(classname); \
if (frameSize < FRAME_SUNDRIES_THRESHOLD) { \
frameSundriesSize += frameSize; \
} else { \
REPORT_SIZE("/layout/frames/" # classname, frameSize, \
"Memory used by frames of " \
"type " #classname " within a window."); \
} \
aWindowTotalSizes->mArenaStats.FRAME_ID_STAT_FIELD(classname) \
+= frameSize; \
}
#include "nsFrameIdList.h"
#undef FRAME_ID
if (frameSundriesSize > 0) {
REPORT_SIZE("/layout/frames/sundries", frameSundriesSize,
"The sum of all memory used by frames which were too small "
"to be shown individually.");
}
#undef REPORT_SIZE
#undef REPORT_COUNT
return NS_OK;
}
typedef nsTArray< nsRefPtr<nsGlobalWindow> > WindowArray;
static
PLDHashOperator
GetWindows(const uint64_t& aId, nsGlobalWindow*& aWindow, void* aClosure)
{
((WindowArray *)aClosure)->AppendElement(aWindow);
return PL_DHASH_NEXT;
}
NS_IMETHODIMP
nsWindowMemoryReporter::CollectReports(nsIMemoryReporterCallback* aCb,
nsISupports* aClosure, bool aAnonymize)
{
nsGlobalWindow::WindowByIdTable* windowsById =
nsGlobalWindow::GetWindowsTable();
NS_ENSURE_TRUE(windowsById, NS_OK);
// Hold on to every window in memory so that window objects can't be
// destroyed while we're calling the memory reporter callback.
WindowArray windows;
windowsById->Enumerate(GetWindows, &windows);
// Get the IDs of all the "ghost" windows, and call aCb->Callback() for each
// one.
nsTHashtable<nsUint64HashKey> ghostWindows;
CheckForGhostWindows(&ghostWindows);
nsresult rv = NS_OK;
for (auto iter = ghostWindows.ConstIter(); !iter.Done(); iter.Next()) {
nsGlobalWindow::WindowByIdTable* windowsById =
nsGlobalWindow::GetWindowsTable();
if (!windowsById) {
NS_WARNING("Couldn't get window-by-id hashtable?");
continue;
}
nsGlobalWindow* window = windowsById->Get(iter.Get()->GetKey());
if (!window) {
NS_WARNING("Could not look up window?");
continue;
}
nsAutoCString path;
path.AppendLiteral("ghost-windows/");
AppendWindowURI(window, path, aAnonymize);
nsresult callbackRv = aCb->Callback(
/* process = */ EmptyCString(),
path,
nsIMemoryReporter::KIND_OTHER,
nsIMemoryReporter::UNITS_COUNT,
/* amount = */ 1,
/* description = */ NS_LITERAL_CSTRING("A ghost window."),
aClosure);
if (NS_FAILED(callbackRv) && NS_SUCCEEDED(rv)) {
rv = callbackRv;
}
}
NS_ENSURE_SUCCESS(rv, rv);
WindowPaths windowPaths;
WindowPaths topWindowPaths;
// Collect window memory usage.
nsWindowSizes windowTotalSizes(nullptr);
nsCOMPtr<amIAddonManager> addonManager;
if (XRE_IsParentProcess()) {
// Only try to access the service from the main process.
addonManager = do_GetService("@mozilla.org/addons/integration;1");
}
for (uint32_t i = 0; i < windows.Length(); i++) {
rv = CollectWindowReports(windows[i], addonManager,
&windowTotalSizes, &ghostWindows,
&windowPaths, &topWindowPaths, aCb,
aClosure, aAnonymize);
NS_ENSURE_SUCCESS(rv, rv);
}
// Report JS memory usage. We do this from here because the JS memory
// reporter needs to be passed |windowPaths|.
rv = xpc::JSReporter::CollectReports(&windowPaths, &topWindowPaths,
aCb, aClosure, aAnonymize);
NS_ENSURE_SUCCESS(rv, rv);
#define REPORT(_path, _amount, _desc) \
do { \
nsresult rv; \
rv = aCb->Callback(EmptyCString(), NS_LITERAL_CSTRING(_path), \
KIND_OTHER, UNITS_BYTES, _amount, \
NS_LITERAL_CSTRING(_desc), aClosure); \
NS_ENSURE_SUCCESS(rv, rv); \
} while (0)
REPORT("window-objects/dom/element-nodes", windowTotalSizes.mDOMElementNodesSize,
"This is the sum of all windows' 'dom/element-nodes' numbers.");
REPORT("window-objects/dom/text-nodes", windowTotalSizes.mDOMTextNodesSize,
"This is the sum of all windows' 'dom/text-nodes' numbers.");
REPORT("window-objects/dom/cdata-nodes", windowTotalSizes.mDOMCDATANodesSize,
"This is the sum of all windows' 'dom/cdata-nodes' numbers.");
REPORT("window-objects/dom/comment-nodes", windowTotalSizes.mDOMCommentNodesSize,
"This is the sum of all windows' 'dom/comment-nodes' numbers.");
REPORT("window-objects/dom/event-targets", windowTotalSizes.mDOMEventTargetsSize,
"This is the sum of all windows' 'dom/event-targets' numbers.");
REPORT("window-objects/dom/other", windowTotalSizes.mDOMOtherSize,
"This is the sum of all windows' 'dom/other' numbers.");
REPORT("window-objects/property-tables",
windowTotalSizes.mPropertyTablesSize,
"This is the sum of all windows' 'property-tables' numbers.");
REPORT("window-objects/style-sheets", windowTotalSizes.mStyleSheetsSize,
"This is the sum of all windows' 'style-sheets' numbers.");
REPORT("window-objects/layout/pres-shell", windowTotalSizes.mLayoutPresShellSize,
"This is the sum of all windows' 'layout/arenas' numbers.");
REPORT("window-objects/layout/line-boxes",
windowTotalSizes.mArenaStats.mLineBoxes,
"This is the sum of all windows' 'layout/line-boxes' numbers.");
REPORT("window-objects/layout/rule-nodes",
windowTotalSizes.mArenaStats.mRuleNodes,
"This is the sum of all windows' 'layout/rule-nodes' numbers.");
REPORT("window-objects/layout/style-contexts",
windowTotalSizes.mArenaStats.mStyleContexts,
"This is the sum of all windows' 'layout/style-contexts' numbers.");
REPORT("window-objects/layout/style-structs",
windowTotalSizes.mArenaStats.mStyleStructs,
"This is the sum of all windows' 'layout/style-structs' numbers.");
REPORT("window-objects/layout/style-sets", windowTotalSizes.mLayoutStyleSetsSize,
"This is the sum of all windows' 'layout/style-sets' numbers.");
REPORT("window-objects/layout/text-runs", windowTotalSizes.mLayoutTextRunsSize,
"This is the sum of all windows' 'layout/text-runs' numbers.");
REPORT("window-objects/layout/pres-contexts", windowTotalSizes.mLayoutPresContextSize,
"This is the sum of all windows' 'layout/pres-contexts' numbers.");
size_t frameTotal = 0;
#define FRAME_ID(classname) \
frameTotal += windowTotalSizes.mArenaStats.FRAME_ID_STAT_FIELD(classname);
#include "nsFrameIdList.h"
#undef FRAME_ID
REPORT("window-objects/layout/frames", frameTotal,
"Memory used for layout frames within windows. "
"This is the sum of all windows' 'layout/frames/' numbers.");
#undef REPORT
return NS_OK;
}
uint32_t
nsWindowMemoryReporter::GetGhostTimeout()
{
return Preferences::GetUint("memory.ghost_window_timeout_seconds", 60);
}
NS_IMETHODIMP
nsWindowMemoryReporter::Observe(nsISupports *aSubject, const char *aTopic,
const char16_t *aData)
{
if (!strcmp(aTopic, DOM_WINDOW_DESTROYED_TOPIC)) {
ObserveDOMWindowDetached(aSubject);
} else if (!strcmp(aTopic, "after-minimize-memory-usage")) {
ObserveAfterMinimizeMemoryUsage();
} else if (!strcmp(aTopic, "cycle-collector-begin")) {
if (mCheckTimer) {
mCheckTimerWaitingForCCEnd = true;
KillCheckTimer();
}
mCycleCollectorIsRunning = true;
} else if (!strcmp(aTopic, "cycle-collector-end")) {
mCycleCollectorIsRunning = false;
if (mCheckTimerWaitingForCCEnd) {
mCheckTimerWaitingForCCEnd = false;
AsyncCheckForGhostWindows();
}
} else {
MOZ_ASSERT(false);
}
return NS_OK;
}
void
nsWindowMemoryReporter::ObserveDOMWindowDetached(nsISupports* aWindow)
{
nsWeakPtr weakWindow = do_GetWeakReference(aWindow);
if (!weakWindow) {
NS_WARNING("Couldn't take weak reference to a window?");
return;
}
mDetachedWindows.Put(weakWindow, TimeStamp());
AsyncCheckForGhostWindows();
}
// static
void
nsWindowMemoryReporter::CheckTimerFired(nsITimer* aTimer, void* aClosure)
{
if (sWindowReporter) {
MOZ_ASSERT(!sWindowReporter->mCycleCollectorIsRunning);
sWindowReporter->CheckForGhostWindows();
}
}
void
nsWindowMemoryReporter::AsyncCheckForGhostWindows()
{
if (mCheckTimer) {
return;
}
if (mCycleCollectorIsRunning) {
mCheckTimerWaitingForCCEnd = true;
return;
}
// If more than kTimeBetweenChecks seconds have elapsed since the last check,
// timerDelay is 0. Otherwise, it is kTimeBetweenChecks, reduced by the time
// since the last check. Reducing the delay by the time since the last check
// prevents the timer from being completely starved if it is repeatedly killed
// and restarted.
int32_t timeSinceLastCheck = (TimeStamp::NowLoRes() - mLastCheckForGhostWindows).ToSeconds();
int32_t timerDelay = (kTimeBetweenChecks - std::min(timeSinceLastCheck, kTimeBetweenChecks)) * PR_MSEC_PER_SEC;
mCheckTimer = do_CreateInstance("@mozilla.org/timer;1");
if (mCheckTimer) {
mCheckTimer->InitWithFuncCallback(CheckTimerFired, nullptr,
timerDelay, nsITimer::TYPE_ONE_SHOT);
}
}
static PLDHashOperator
BackdateTimeStampsEnumerator(nsISupports *aKey, TimeStamp &aTimeStamp,
void* aClosure)
{
TimeStamp *minTimeStamp = static_cast<TimeStamp*>(aClosure);
if (!aTimeStamp.IsNull() && aTimeStamp > *minTimeStamp) {
aTimeStamp = *minTimeStamp;
}
return PL_DHASH_NEXT;
}
void
nsWindowMemoryReporter::ObserveAfterMinimizeMemoryUsage()
{
// Someone claims they've done enough GC/CCs so that all eligible windows
// have been free'd. So we deem that any windows which satisfy ghost
// criteria (1) and (2) now satisfy criterion (3) as well.
//
// To effect this change, we'll backdate some of our timestamps.
TimeStamp minTimeStamp = TimeStamp::Now() -
TimeDuration::FromSeconds(GetGhostTimeout());
mDetachedWindows.Enumerate(BackdateTimeStampsEnumerator,
&minTimeStamp);
}
struct CheckForGhostWindowsEnumeratorData
{
nsTHashtable<nsCStringHashKey> *nonDetachedDomains;
nsTHashtable<nsUint64HashKey> *ghostWindowIDs;
nsIEffectiveTLDService *tldService;
uint32_t ghostTimeout;
TimeStamp now;
};
static PLDHashOperator
CheckForGhostWindowsEnumerator(nsISupports *aKey, TimeStamp& aTimeStamp,
void* aClosure)
{
CheckForGhostWindowsEnumeratorData *data =
static_cast<CheckForGhostWindowsEnumeratorData*>(aClosure);
nsWeakPtr weakKey = do_QueryInterface(aKey);
nsCOMPtr<nsPIDOMWindow> window = do_QueryReferent(weakKey);
if (!window) {
// The window object has been destroyed. Stop tracking its weak ref in our
// hashtable.
return PL_DHASH_REMOVE;
}
// Avoid calling GetTop() if we have no outer window. Nothing will break if
// we do, but it will spew debug output, which can cause our test logs to
// overflow.
nsCOMPtr<nsIDOMWindow> top;
if (window->GetOuterWindow()) {
window->GetTop(getter_AddRefs(top));
}
if (top) {
// The window is no longer detached, so we no longer want to track it.
return PL_DHASH_REMOVE;
}
nsCOMPtr<nsIURI> uri = GetWindowURI(window);
nsAutoCString domain;
if (uri) {
// GetBaseDomain works fine if |uri| is null, but it outputs a warning
// which ends up overrunning the mochitest logs.
data->tldService->GetBaseDomain(uri, 0, domain);
}
if (data->nonDetachedDomains->Contains(domain)) {
// This window shares a domain with a non-detached window, so reset its
// clock.
aTimeStamp = TimeStamp();
} else {
// This window does not share a domain with a non-detached window, so it
// meets ghost criterion (2).
if (aTimeStamp.IsNull()) {
// This may become a ghost window later; start its clock.
aTimeStamp = data->now;
} else if ((data->now - aTimeStamp).ToSeconds() > data->ghostTimeout) {
// This definitely is a ghost window, so add it to ghostWindowIDs, if
// that is not null.
if (data->ghostWindowIDs) {
nsCOMPtr<nsPIDOMWindow> pWindow = do_QueryInterface(window);
if (pWindow) {
data->ghostWindowIDs->PutEntry(pWindow->WindowID());
}
}
}
}
return PL_DHASH_NEXT;
}
struct GetNonDetachedWindowDomainsEnumeratorData
{
nsTHashtable<nsCStringHashKey> *nonDetachedDomains;
nsIEffectiveTLDService *tldService;
};
static PLDHashOperator
GetNonDetachedWindowDomainsEnumerator(const uint64_t& aId, nsGlobalWindow* aWindow,
void* aClosure)
{
GetNonDetachedWindowDomainsEnumeratorData *data =
static_cast<GetNonDetachedWindowDomainsEnumeratorData*>(aClosure);
// Null outer window implies null top, but calling GetTop() when there's no
// outer window causes us to spew debug warnings.
if (!aWindow->GetOuterWindow() || !aWindow->GetTop()) {
// This window is detached, so we don't care about its domain.
return PL_DHASH_NEXT;
}
nsCOMPtr<nsIURI> uri = GetWindowURI(aWindow);
nsAutoCString domain;
if (uri) {
data->tldService->GetBaseDomain(uri, 0, domain);
}
data->nonDetachedDomains->PutEntry(domain);
return PL_DHASH_NEXT;
}
/**
* Iterate over mDetachedWindows and update it to reflect the current state of
* the world. In particular:
*
* - Remove weak refs to windows which no longer exist.
*
* - Remove references to windows which are no longer detached.
*
* - Reset the timestamp on detached windows which share a domain with a
* non-detached window (they no longer meet ghost criterion (2)).
*
* - If a window now meets ghost criterion (2) but didn't before, set its
* timestamp to now.
*
* Additionally, if aOutGhostIDs is not null, fill it with the window IDs of
* all ghost windows we found.
*/
void
nsWindowMemoryReporter::CheckForGhostWindows(
nsTHashtable<nsUint64HashKey> *aOutGhostIDs /* = nullptr */)
{
nsCOMPtr<nsIEffectiveTLDService> tldService = do_GetService(
NS_EFFECTIVETLDSERVICE_CONTRACTID);
if (!tldService) {
NS_WARNING("Couldn't get TLDService.");
return;
}
nsGlobalWindow::WindowByIdTable *windowsById =
nsGlobalWindow::GetWindowsTable();
if (!windowsById) {
NS_WARNING("GetWindowsTable returned null");
return;
}
mLastCheckForGhostWindows = TimeStamp::NowLoRes();
KillCheckTimer();
nsTHashtable<nsCStringHashKey> nonDetachedWindowDomains;
// Populate nonDetachedWindowDomains.
GetNonDetachedWindowDomainsEnumeratorData nonDetachedEnumData =
{ &nonDetachedWindowDomains, tldService };
windowsById->EnumerateRead(GetNonDetachedWindowDomainsEnumerator,
&nonDetachedEnumData);
// Update mDetachedWindows and write the ghost window IDs into aOutGhostIDs,
// if it's not null.
CheckForGhostWindowsEnumeratorData ghostEnumData =
{ &nonDetachedWindowDomains, aOutGhostIDs, tldService,
GetGhostTimeout(), mLastCheckForGhostWindows };
mDetachedWindows.Enumerate(CheckForGhostWindowsEnumerator,
&ghostEnumData);
}
NS_IMPL_ISUPPORTS(nsWindowMemoryReporter::GhostWindowsReporter,
nsIMemoryReporter)
/* static */ int64_t
nsWindowMemoryReporter::GhostWindowsReporter::DistinguishedAmount()
{
nsTHashtable<nsUint64HashKey> ghostWindows;
sWindowReporter->CheckForGhostWindows(&ghostWindows);
return ghostWindows.Count();
}
void
nsWindowMemoryReporter::KillCheckTimer()
{
if (mCheckTimer) {
mCheckTimer->Cancel();
mCheckTimer = nullptr;
}
}
#ifdef DEBUG
/* static */ void
nsWindowMemoryReporter::UnlinkGhostWindows()
{
if (!sWindowReporter) {
return;
}
nsGlobalWindow::WindowByIdTable* windowsById =
nsGlobalWindow::GetWindowsTable();
if (!windowsById) {
return;
}
// Hold on to every window in memory so that window objects can't be
// destroyed while we're calling the UnlinkGhostWindows callback.
WindowArray windows;
windowsById->Enumerate(GetWindows, &windows);
// Get the IDs of all the "ghost" windows, and unlink them all.
nsTHashtable<nsUint64HashKey> ghostWindows;
sWindowReporter->CheckForGhostWindows(&ghostWindows);
for (auto iter = ghostWindows.ConstIter(); !iter.Done(); iter.Next()) {
nsGlobalWindow::WindowByIdTable* windowsById =
nsGlobalWindow::GetWindowsTable();
if (!windowsById) {
continue;
}
nsRefPtr<nsGlobalWindow> window = windowsById->Get(iter.Get()->GetKey());
if (window) {
window->RiskyUnlink();
}
}
}
#endif