fune/browser/modules/ProcessHangMonitor.sys.mjs
Norisz Fay 0d4fc02631 Backed out 7 changesets (bug 1845150) for causing failures on browser_datachoices_notification.js CLOSED TREE
Backed out changeset a07c835a4bf7 (bug 1845150)
Backed out changeset 0016d7f4e556 (bug 1845150)
Backed out changeset 46cfe5fe6e6a (bug 1845150)
Backed out changeset 83190b8a08d0 (bug 1845150)
Backed out changeset ada948351267 (bug 1845150)
Backed out changeset 7aa4340bfd96 (bug 1845150)
Backed out changeset 683745289588 (bug 1845150)
2024-01-05 18:52:01 +02:00

687 lines
20 KiB
JavaScript

/* -*- mode: js; indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* 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/. */
import { AppConstants } from "resource://gre/modules/AppConstants.sys.mjs";
/**
* Elides the middle of a string by replacing it with an elipsis if it is
* longer than `threshold` characters. Does its best to not break up grapheme
* clusters.
*/
function elideMiddleOfString(str, threshold) {
const searchDistance = 5;
const stubLength = threshold / 2 - searchDistance;
if (str.length <= threshold || stubLength < searchDistance) {
return str;
}
function searchElisionPoint(position) {
let unsplittableCharacter = c => /[\p{M}\uDC00-\uDFFF]/u.test(c);
for (let i = 0; i < searchDistance; i++) {
if (!unsplittableCharacter(str[position + i])) {
return position + i;
}
if (!unsplittableCharacter(str[position - i])) {
return position - i;
}
}
return position;
}
let elisionStart = searchElisionPoint(stubLength);
let elisionEnd = searchElisionPoint(str.length - stubLength);
if (elisionStart < elisionEnd) {
str = str.slice(0, elisionStart) + "\u2026" + str.slice(elisionEnd);
}
return str;
}
/**
* This JSM is responsible for observing content process hang reports
* and asking the user what to do about them. See nsIHangReport for
* the platform interface.
*/
export var ProcessHangMonitor = {
/**
* This timeout is the wait period applied after a user selects "Wait" in
* an existing notification.
*/
get WAIT_EXPIRATION_TIME() {
try {
return Services.prefs.getIntPref("browser.hangNotification.waitPeriod");
} catch (ex) {
return 10000;
}
},
/**
* Should only be set to true once the quit-application-granted notification
* has been fired.
*/
_shuttingDown: false,
/**
* Collection of hang reports that haven't expired or been dismissed
* by the user. These are nsIHangReports. They are mapped to objects
* containing:
* - notificationTime: when (Cu.now()) we first showed a notification
* - waitCount: how often the user asked to wait for the script to finish
* - lastReportFromChild: when (Cu.now()) we last got hang info from the
* child.
*/
_activeReports: new Map(),
/**
* Collection of hang reports that have been suppressed for a short
* period of time. Value is an object like in _activeReports, but also
* including a `timer` prop, which is an nsITimer for when the wait time
* expires.
*/
_pausedReports: new Map(),
/**
* Initialize hang reporting. Called once in the parent process.
*/
init() {
Services.obs.addObserver(this, "process-hang-report");
Services.obs.addObserver(this, "clear-hang-report");
Services.obs.addObserver(this, "quit-application-granted");
Services.obs.addObserver(this, "xpcom-shutdown");
Services.ww.registerNotification(this);
Services.telemetry.setEventRecordingEnabled("slow_script_warning", true);
},
/**
* Terminate JavaScript associated with the hang being reported for
* the selected browser in |win|.
*/
terminateScript(win) {
this.handleUserInput(win, report => report.terminateScript());
},
/**
* Start devtools debugger for JavaScript associated with the hang
* being reported for the selected browser in |win|.
*/
debugScript(win) {
this.handleUserInput(win, report => {
function callback() {
report.endStartingDebugger();
}
this._recordTelemetryForReport(report, "debugging");
report.beginStartingDebugger();
let svc = Cc["@mozilla.org/dom/slow-script-debug;1"].getService(
Ci.nsISlowScriptDebug
);
let handler = svc.remoteActivationHandler;
handler.handleSlowScriptDebug(report.scriptBrowser, callback);
});
},
/**
* Dismiss the browser notification and invoke an appropriate action based on
* the hang type.
*/
stopIt(win) {
let report = this.findActiveReport(win.gBrowser.selectedBrowser);
if (!report) {
return;
}
this._recordTelemetryForReport(report, "user-aborted");
this.terminateScript(win);
},
/**
* Terminate the script causing this report. This is done without
* updating any report notifications.
*/
stopHang(report, endReason, backupInfo) {
this._recordTelemetryForReport(report, endReason, backupInfo);
report.terminateScript();
},
/**
* Dismiss the notification, clear the report from the active list and set up
* a new timer to track a wait period during which we won't notify.
*/
waitLonger(win) {
let report = this.findActiveReport(win.gBrowser.selectedBrowser);
if (!report) {
return;
}
// Update the other info we keep.
let reportInfo = this._activeReports.get(report);
reportInfo.waitCount++;
// Remove the report from the active list.
this.removeActiveReport(report);
// NOTE, we didn't call userCanceled on nsIHangReport here. This insures
// we don't repeatedly generate and cache crash report data for this hang
// in the process hang reporter. It already has one report for the browser
// process we want it hold onto.
// Create a new wait timer with notify callback
let timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
timer.initWithCallback(
() => {
for (let [stashedReport, pausedInfo] of this._pausedReports) {
if (pausedInfo.timer === timer) {
this.removePausedReport(stashedReport);
// We're still hung, so move the report back to the active
// list and update the UI.
this._activeReports.set(report, pausedInfo);
this.updateWindows();
break;
}
}
},
this.WAIT_EXPIRATION_TIME,
timer.TYPE_ONE_SHOT
);
reportInfo.timer = timer;
this._pausedReports.set(report, reportInfo);
// remove the browser notification associated with this hang
this.updateWindows();
},
/**
* If there is a hang report associated with the selected browser in
* |win|, invoke |func| on that report and stop notifying the user
* about it.
*/
handleUserInput(win, func) {
let report = this.findActiveReport(win.gBrowser.selectedBrowser);
if (!report) {
return null;
}
this.removeActiveReport(report);
return func(report);
},
observe(subject, topic, data) {
switch (topic) {
case "xpcom-shutdown": {
Services.obs.removeObserver(this, "xpcom-shutdown");
Services.obs.removeObserver(this, "process-hang-report");
Services.obs.removeObserver(this, "clear-hang-report");
Services.obs.removeObserver(this, "quit-application-granted");
Services.ww.unregisterNotification(this);
break;
}
case "quit-application-granted": {
this.onQuitApplicationGranted();
break;
}
case "process-hang-report": {
this.reportHang(subject.QueryInterface(Ci.nsIHangReport));
break;
}
case "clear-hang-report": {
this.clearHang(subject.QueryInterface(Ci.nsIHangReport));
break;
}
case "domwindowopened": {
// Install event listeners on the new window in case one of
// its tabs is already hung.
let win = subject;
let listener = ev => {
win.removeEventListener("load", listener, true);
this.updateWindows();
};
win.addEventListener("load", listener, true);
break;
}
case "domwindowclosed": {
let win = subject;
this.onWindowClosed(win);
break;
}
}
},
/**
* Called early on in the shutdown sequence. We take this opportunity to
* take any pre-existing hang reports, and terminate them. We also put
* ourselves in a state so that if any more hang reports show up while
* we're shutting down, we terminate them immediately.
*/
onQuitApplicationGranted() {
this._shuttingDown = true;
this.stopAllHangs("quit-application-granted");
this.updateWindows();
},
onWindowClosed(win) {
let maybeStopHang = report => {
let hungBrowserWindow = null;
try {
hungBrowserWindow = report.scriptBrowser.ownerGlobal;
} catch (e) {
// Ignore failures to get the script browser - we'll be
// conservative, and assume that if we cannot access the
// window that belongs to this report that we should stop
// the hang.
}
if (!hungBrowserWindow || hungBrowserWindow == win) {
this.stopHang(report, "window-closed");
return true;
}
return false;
};
// If there are any script hangs for browsers that are in this window
// that is closing, we can stop them now.
for (let [report] of this._activeReports) {
if (maybeStopHang(report)) {
this._activeReports.delete(report);
}
}
for (let [pausedReport] of this._pausedReports) {
if (maybeStopHang(pausedReport)) {
this.removePausedReport(pausedReport);
}
}
this.updateWindows();
},
stopAllHangs(endReason) {
for (let [report] of this._activeReports) {
this.stopHang(report, endReason);
}
this._activeReports = new Map();
for (let [pausedReport] of this._pausedReports) {
this.stopHang(pausedReport, endReason);
this.removePausedReport(pausedReport);
}
},
/**
* Find a active hang report for the given <browser> element.
*/
findActiveReport(browser) {
let frameLoader = browser.frameLoader;
for (let report of this._activeReports.keys()) {
if (report.isReportForBrowserOrChildren(frameLoader)) {
return report;
}
}
return null;
},
/**
* Find a paused hang report for the given <browser> element.
*/
findPausedReport(browser) {
let frameLoader = browser.frameLoader;
for (let [report] of this._pausedReports) {
if (report.isReportForBrowserOrChildren(frameLoader)) {
return report;
}
}
return null;
},
/**
* Tell telemetry about the report.
*/
_recordTelemetryForReport(report, endReason, backupInfo) {
let info =
this._activeReports.get(report) ||
this._pausedReports.get(report) ||
backupInfo;
if (!info) {
return;
}
try {
let uri_type;
if (report.addonId) {
uri_type = "extension";
} else if (report.scriptFileName?.startsWith("debugger")) {
uri_type = "devtools";
} else {
try {
let url = new URL(report.scriptFileName);
if (url.protocol == "chrome:" || url.protocol == "resource:") {
uri_type = "browser";
} else {
uri_type = "content";
}
} catch (ex) {
console.error(ex);
uri_type = "unknown";
}
}
let uptime = 0;
if (info.notificationTime) {
uptime = Cu.now() - info.notificationTime;
}
uptime = "" + uptime;
// We combine the duration of the hang in the content process with the
// time since we were last told about the hang in the parent. This is
// not the same as the time we showed a notification, as we only do that
// for the currently selected browser. It's as messy as it is because
// there is no cross-process monotonically increasing timestamp we can
// use. :-(
let hangDuration =
report.hangDuration + Cu.now() - info.lastReportFromChild;
Services.telemetry.recordEvent(
"slow_script_warning",
"shown",
"content",
null,
{
end_reason: endReason,
hang_duration: "" + hangDuration,
n_tab_deselect: "" + info.deselectCount,
uri_type,
uptime,
wait_count: "" + info.waitCount,
}
);
} catch (ex) {
console.error(ex);
}
},
/**
* Remove an active hang report from the active list and cancel the timer
* associated with it.
*/
removeActiveReport(report) {
this._activeReports.delete(report);
this.updateWindows();
},
/**
* Remove a paused hang report from the paused list and cancel the timer
* associated with it.
*/
removePausedReport(report) {
let info = this._pausedReports.get(report);
info?.timer?.cancel();
this._pausedReports.delete(report);
},
/**
* Iterate over all XUL windows and ensure that the proper hang
* reports are shown for each one. Also install event handlers in
* each window to watch for events that would cause a different hang
* report to be displayed.
*/
updateWindows() {
let e = Services.wm.getEnumerator("navigator:browser");
// If it turns out we have no windows (this can happen on macOS),
// we have no opportunity to ask the user whether or not they want
// to stop the hang or wait, so we'll opt for stopping the hang.
if (!e.hasMoreElements()) {
this.stopAllHangs("no-windows-left");
return;
}
for (let win of e) {
this.updateWindow(win);
// Only listen for these events if there are active hang reports.
if (this._activeReports.size) {
this.trackWindow(win);
} else {
this.untrackWindow(win);
}
}
},
/**
* If there is a hang report for the current tab in |win|, display it.
*/
updateWindow(win) {
let report = this.findActiveReport(win.gBrowser.selectedBrowser);
if (report) {
let info = this._activeReports.get(report);
if (info && !info.notificationTime) {
info.notificationTime = Cu.now();
}
this.showNotification(win, report);
} else {
this.hideNotification(win);
}
},
/**
* Show the notification for a hang.
*/
showNotification(win, report) {
let bundle = win.gNavigatorBundle;
let buttons = [
{
label: bundle.getString("processHang.button_stop2.label"),
accessKey: bundle.getString("processHang.button_stop2.accessKey"),
callback() {
ProcessHangMonitor.stopIt(win);
},
},
];
let message;
let doc = win.document;
let brandShortName = doc
.getElementById("bundle_brand")
.getString("brandShortName");
let notificationTag;
if (report.addonId) {
notificationTag = report.addonId;
let aps = Cc["@mozilla.org/addons/policy-service;1"].getService(
Ci.nsIAddonPolicyService
);
let addonName = aps.getExtensionName(report.addonId);
message = bundle.getFormattedString("processHang.add-on.label2", [
addonName,
brandShortName,
]);
buttons.unshift({
label: bundle.getString("processHang.add-on.learn-more.text"),
link: "https://support.mozilla.org/kb/warning-unresponsive-script#w_other-causes",
});
} else {
let scriptBrowser = report.scriptBrowser;
if (scriptBrowser == win.gBrowser?.selectedBrowser) {
notificationTag = "selected-tab";
message = bundle.getFormattedString("processHang.selected_tab.label", [
brandShortName,
]);
} else {
let tab =
scriptBrowser?.ownerGlobal.gBrowser?.getTabForBrowser(scriptBrowser);
if (!tab) {
notificationTag = "nonspecific_tab";
message = bundle.getFormattedString(
"processHang.nonspecific_tab.label",
[brandShortName]
);
} else {
notificationTag = scriptBrowser.browserId.toString();
let title = tab.getAttribute("label");
title = elideMiddleOfString(title, 60);
message = bundle.getFormattedString(
"processHang.specific_tab.label",
[title, brandShortName]
);
}
}
}
let notification =
win.gNotificationBox.getNotificationWithValue("process-hang");
if (notificationTag == notification?.getAttribute("notification-tag")) {
return;
}
if (notification) {
notification.label = message;
notification.setAttribute("notification-tag", notificationTag);
return;
}
// Show the "debug script" button unconditionally if we are in Developer edition,
// or, if DevTools are opened on the slow tab.
if (
AppConstants.MOZ_DEV_EDITION ||
report.scriptBrowser.browsingContext.watchedByDevTools
) {
buttons.push({
label: bundle.getString("processHang.button_debug.label"),
accessKey: bundle.getString("processHang.button_debug.accessKey"),
callback() {
ProcessHangMonitor.debugScript(win);
},
});
}
win.gNotificationBox
.appendNotification(
"process-hang",
{
label: message,
image: "chrome://browser/content/aboutRobots-icon.png",
priority: win.gNotificationBox.PRIORITY_INFO_HIGH,
eventCallback: event => {
if (event == "dismissed") {
ProcessHangMonitor.waitLonger(win);
}
},
},
buttons
)
.setAttribute("notification-tag", notificationTag);
},
/**
* Ensure that no hang notifications are visible in |win|.
*/
hideNotification(win) {
let notification =
win.gNotificationBox.getNotificationWithValue("process-hang");
if (notification) {
win.gNotificationBox.removeNotification(notification);
}
},
/**
* Install event handlers on |win| to watch for events that would
* cause a different hang report to be displayed.
*/
trackWindow(win) {
win.gBrowser.tabContainer.addEventListener("TabSelect", this, true);
win.gBrowser.tabContainer.addEventListener(
"TabRemotenessChange",
this,
true
);
},
untrackWindow(win) {
win.gBrowser.tabContainer.removeEventListener("TabSelect", this, true);
win.gBrowser.tabContainer.removeEventListener(
"TabRemotenessChange",
this,
true
);
},
handleEvent(event) {
let win = event.target.ownerGlobal;
// If a new tab is selected or if a tab changes remoteness, then
// we may need to show or hide a hang notification.
if (event.type == "TabSelect" || event.type == "TabRemotenessChange") {
if (event.type == "TabSelect" && event.detail.previousTab) {
// If we've got a notification, check the previous tab's report and
// indicate the user switched tabs while the notification was up.
let r =
this.findActiveReport(event.detail.previousTab.linkedBrowser) ||
this.findPausedReport(event.detail.previousTab.linkedBrowser);
if (r) {
let info = this._activeReports.get(r) || this._pausedReports.get(r);
info.deselectCount++;
}
}
this.updateWindow(win);
}
},
/**
* Handle a potentially new hang report. If it hasn't been seen
* before, show a notification for it in all open XUL windows.
*/
reportHang(report) {
let now = Cu.now();
if (this._shuttingDown) {
this.stopHang(report, "shutdown-in-progress", {
lastReportFromChild: now,
waitCount: 0,
deselectCount: 0,
});
return;
}
// If this hang was already reported reset the timer for it.
if (this._activeReports.has(report)) {
this._activeReports.get(report).lastReportFromChild = now;
// if this report is in active but doesn't have a notification associated
// with it, display a notification.
this.updateWindows();
return;
}
// If this hang was already reported and paused by the user ignore it.
if (this._pausedReports.has(report)) {
this._pausedReports.get(report).lastReportFromChild = now;
return;
}
// On e10s this counts slow-script notice only once.
// This code is not reached on non-e10s.
Services.telemetry.getHistogramById("SLOW_SCRIPT_NOTICE_COUNT").add();
this._activeReports.set(report, {
deselectCount: 0,
lastReportFromChild: now,
waitCount: 0,
});
this.updateWindows();
},
clearHang(report) {
this._recordTelemetryForReport(report, "cleared");
this.removeActiveReport(report);
this.removePausedReport(report);
report.userCanceled();
},
};