tor-browser

commit b9c976f8352afd38ed02994dc8128572b6d99587
parent 277143444995b7e65f9222e5eff8f6ea3fba7516
Author: Alexandre Poirot <poirot.alex@gmail.com>
Date:   Tue, 18 Nov 2025 10:02:51 +0000

Bug 1994951 - [devtools] Toggle console and PageMessages MOZ_LOG when using the Web Compat profiler preset. r=canaltinova,profiler-reviewers

Differential Revision: https://phabricator.services.mozilla.com/D269242

Diffstat:
M
devtools/client/performance-new/@types/perf.d.ts
 | 
2
++
M
devtools/client/performance-new/shared/background.sys.mjs
 | 
56
+++++++++++++++++++++++++++++++++++++++++++++++++++++++-
M
devtools/shared/performance-new/prefs-presets.sys.mjs
 | 
2
++

3 files changed, 59 insertions(+), 1 deletion(-)
diff --git a/devtools/client/performance-new/@types/perf.d.ts b/devtools/client/performance-new/@types/perf.d.ts
@@ -203,6 +203,7 @@ export interface RecordingSettings {
   objdirs: string[];
   // The duration is currently not wired up to the UI yet. See Bug 1587165.
   duration?: number;
+  mozLogs?: string;
 }
 
 /**
@@ -447,6 +448,7 @@ export interface PresetDefinition {
   threads: string[];
   duration: number;
   profilerViewMode?: ProfilerViewMode;
+  mozLogs?: string;
   l10nIds: {
     popup: {
       label: string;
diff --git a/devtools/client/performance-new/shared/background.sys.mjs b/devtools/client/performance-new/shared/background.sys.mjs
@@ -89,6 +89,9 @@ const lazy = createLazyLoaders({
       .PlacesUtils,
 });
 
+/** @type {{[key:string]: number} | null} */
+let gPreviousMozLogValues = null;
+
 /**
  * This function is called when the profile is captured with the shortcut keys,
  * with the profiler toolbarbutton, with the button inside the popup, or with
@@ -110,6 +113,7 @@ export async function captureProfile(pageContext) {
   const { profileCaptureResult, additionalInformation } = await lazy
     .RecordingUtils()
     .getProfileDataAsGzippedArrayBufferThenStop();
+  cleanupMozLogs();
   const profilerViewMode = lazy
     .PrefsPresets()
     .getProfilerViewModeForCurrentPreset(pageContext);
@@ -142,7 +146,7 @@ export async function captureProfile(pageContext) {
  * @param {PageContext} pageContext
  */
 export function startProfiler(pageContext) {
-  const { entries, interval, features, threads, duration } = lazy
+  const { entries, interval, features, threads, mozLogs, duration } = lazy
     .PrefsPresets()
     .getRecordingSettings(pageContext, Services.profiler.GetFeatures());
 
@@ -150,6 +154,10 @@ export function startProfiler(pageContext) {
   const { getActiveBrowserID } = lazy.RecordingUtils();
   const activeTabID = getActiveBrowserID();
 
+  if (typeof mozLogs == "string") {
+    updateMozLogs(mozLogs);
+  }
+
   Services.profiler.StartProfiler(
     entries,
     interval,
@@ -161,6 +169,31 @@ export function startProfiler(pageContext) {
 }
 
 /**
+ * Given a MOZ_LOG string, toggles the expected preferences to enable the
+ * LogModules mentioned in the string at the expected level of logging.
+ * This will also record preference values in order to reset them on stop.
+ * `mozLogs` is a string similar to the one passed as MOZ_LOG env variable.
+ *
+ * @param {string} mozLogs
+ */
+function updateMozLogs(mozLogs) {
+  gPreviousMozLogValues = {};
+  for (const module of mozLogs.split(",")) {
+    const lastColon = module.lastIndexOf(":");
+    const logName = module.slice(0, lastColon).trim();
+    const value = parseInt(module.slice(lastColon + 1).trim(), 10);
+    const prefName = `logging.${logName}`;
+    gPreviousMozLogValues[prefName] = Services.prefs.getIntPref(
+      prefName,
+      undefined
+    );
+    // MOZ_LOG aren't profiler specific and enabled globally in Firefox.
+    // Preferences are the easiest (only?) way to toggle them from JavaScript.
+    Services.prefs.setIntPref(prefName, value);
+  }
+}
+
+/**
  * This function is called directly by devtools/startup/DevToolsStartup.jsm when
  * using the shortcut keys to capture a profile.
  *
@@ -168,6 +201,27 @@ export function startProfiler(pageContext) {
  */
 export function stopProfiler() {
   Services.profiler.StopProfiler();
+
+  cleanupMozLogs();
+}
+
+/**
+ * This function should be called when we are done profiler in order to reset
+ * the MOZ_LOG enabled while profiling.
+ *
+ * @type {() => void}
+ */
+export function cleanupMozLogs() {
+  if (gPreviousMozLogValues) {
+    for (const [prefName, value] of Object.entries(gPreviousMozLogValues)) {
+      if (typeof value == "number") {
+        Services.prefs.setIntPref(prefName, value);
+      } else {
+        Services.prefs.clearUserPref(prefName);
+      }
+    }
+    gPreviousMozLogValues = null;
+  }
 }
 
 /**
diff --git a/devtools/shared/performance-new/prefs-presets.sys.mjs b/devtools/shared/performance-new/prefs-presets.sys.mjs
@@ -298,6 +298,7 @@ export const presets = {
     interval: 1,
     features: ["screenshots", "js", "stackwalk", "nostacksampling", "tracing"],
     threads: ["GeckoMain", "DOM Worker"],
+    mozLogs: "console: 5, PageMessages: 5",
     duration: 0,
     profilerViewMode: "active-tab",
     l10nIds: {
@@ -539,6 +540,7 @@ export function getRecordingSettingsFromPreset(
       supportedFeatures.includes(feature)
     ),
     threads: preset.threads,
+    mozLogs: preset.mozLogs,
     objdirs,
     duration: preset.duration,
   };