tor-browser

commit bc6ccb4c0628ba4148b39eb0da8c1c4317206906
parent bad6494dd2179d1dbc950f6645a291737e1cb0f8
Author: Paul Bone <paul@bone.id.au>
Date:   Tue,  9 Dec 2025 03:12:40 +0000

Bug 1996828 - Move the shutdown observer into TelemetryImpl r=toolkit-telemetry-reviewers,chutten

This shutdown observer flushes telemetry from content processes during
shutdown.  It may have been created for memory telemetry but it's more
general.

Differential Revision: https://phabricator.services.mozilla.com/D274874

Diffstat:
M
toolkit/components/telemetry/core/Telemetry.cpp
 | 
32
++++++++++++++++++++++++++++++--
M
xpcom/base/MemoryTelemetry.cpp
 | 
33
++-------------------------------
M
xpcom/base/MemoryTelemetry.h
 | 
7
+------

3 files changed, 33 insertions(+), 39 deletions(-)
diff --git a/toolkit/components/telemetry/core/Telemetry.cpp b/toolkit/components/telemetry/core/Telemetry.cpp
@@ -57,6 +57,8 @@
 #include "nsDirectoryServiceDefs.h"
 #include "nsIFileStreams.h"
 #include "nsIMemoryReporter.h"
+#include "nsIObserver.h"
+#include "nsIObserverService.h"
 #include "nsISeekableStream.h"
 #include "nsITelemetry.h"
 #if defined(XP_WIN)
@@ -110,10 +112,13 @@ void ClearIOReporting() {
   sTelemetryIOObserver = nullptr;
 }
 
-class TelemetryImpl final : public nsITelemetry, public nsIMemoryReporter {
+class TelemetryImpl final : public nsITelemetry,
+                            public nsIMemoryReporter,
+                            public nsIObserver {
   NS_DECL_THREADSAFE_ISUPPORTS
   NS_DECL_NSITELEMETRY
   NS_DECL_NSIMEMORYREPORTER
+  NS_DECL_NSIOBSERVER
 
  public:
   void InitMemoryReporter();
@@ -1019,6 +1024,8 @@ static const TrackedDBEntry kTrackedDBPrefixes[] = {
 
 #undef TRACKEDDB_ENTRY
 
+static constexpr const char* kTopicShutdown = "content-child-shutdown";
+
 // Slow SQL statements will be automatically
 // trimmed to kMaxSlowStatementLength characters.
 // This limit doesn't include the ellipsis and DB name,
@@ -1109,7 +1116,7 @@ bool TelemetryImpl::CanRecordReleaseData() { return CanRecordBase(); }
 
 bool TelemetryImpl::CanRecordPrereleaseData() { return CanRecordExtended(); }
 
-NS_IMPL_ISUPPORTS(TelemetryImpl, nsITelemetry, nsIMemoryReporter)
+NS_IMPL_ISUPPORTS(TelemetryImpl, nsITelemetry, nsIMemoryReporter, nsITelemetry)
 
 NS_IMETHODIMP
 TelemetryImpl::GetFileIOReports(JSContext* cx,
@@ -1214,6 +1221,14 @@ TelemetryImpl::EarlyInit() {
   }
   mMemoryTelemetry = MemoryTelemetry::Create();
   MOZ_ASSERT(mMemoryTelemetry);
+
+  if (XRE_IsContentProcess()) {
+    nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+    MOZ_RELEASE_ASSERT(obs);
+
+    obs->AddObserver(this, kTopicShutdown, true);
+  }
+
   return NS_OK;
 }
 
@@ -1228,9 +1243,14 @@ TelemetryImpl::DelayedInit() {
 
 NS_IMETHODIMP
 TelemetryImpl::Shutdown() {
+  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+  MOZ_RELEASE_ASSERT(obs);
+  obs->RemoveObserver(this, kTopicShutdown);
+
   if (!mMemoryTelemetry) {
     return NS_ERROR_FAILURE;
   }
+
   mMemoryTelemetry->Shutdown();
   mMemoryTelemetry = nullptr;
   return NS_OK;
@@ -1293,6 +1313,14 @@ TelemetryImpl::GetAllStores(JSContext* aCx,
   return NS_OK;
 }
 
+nsresult TelemetryImpl::Observe(nsISupports* aSubject, const char* aTopic,
+                                const char16_t* aData) {
+  if (strcmp(aTopic, kTopicShutdown) == 0) {
+    FlushBatchedChildTelemetry();
+  }
+  return NS_OK;
+}
+
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////
diff --git a/xpcom/base/MemoryTelemetry.cpp b/xpcom/base/MemoryTelemetry.cpp
@@ -30,7 +30,6 @@
 #include "nsImportModule.h"
 #include "nsITelemetry.h"
 #include "nsNetCID.h"
-#include "nsObserverService.h"
 #include "nsReadableUtils.h"
 #include "nsThreadUtils.h"
 #include "nsXULAppAPI.h"
@@ -56,8 +55,6 @@ static constexpr uint32_t kTelemetryCooldownS = 10;
 static constexpr unsigned kPokeWindowEvents = 10;
 static constexpr unsigned kPokeWindowSeconds = 1;
 
-static constexpr const char* kTopicShutdown = "content-child-shutdown";
-
 namespace {
 
 enum class PrevValue : uint32_t {
@@ -119,22 +116,13 @@ class TimeStampWindow {
   AutoCleanLinkedList<Event> mEvents;
 };
 
-NS_IMPL_ISUPPORTS(MemoryTelemetry, nsIObserver, nsISupportsWeakReference)
+NS_IMPL_ISUPPORTS(MemoryTelemetry, nsISupportsWeakReference)
 
 MemoryTelemetry::MemoryTelemetry()
-    : mThreadPool(do_GetService(NS_STREAMTRANSPORTSERVICE_CONTRACTID)) {}
-
-void MemoryTelemetry::Init() {
+    : mThreadPool(do_GetService(NS_STREAMTRANSPORTSERVICE_CONTRACTID)) {
   for (auto& val : gPrevValues) {
     val = kUninitialized;
   }
-
-  if (XRE_IsContentProcess()) {
-    nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
-    MOZ_RELEASE_ASSERT(obs);
-
-    obs->AddObserver(this, kTopicShutdown, true);
-  }
 }
 
 static StaticRefPtr<MemoryTelemetry> sInstance;
@@ -144,7 +132,6 @@ static StaticRefPtr<MemoryTelemetry> sInstance;
 
   if (!sInstance) {
     sInstance = new MemoryTelemetry();
-    sInstance->Init();
     ClearOnShutdown(&sInstance);
   }
 
@@ -236,11 +223,6 @@ nsresult MemoryTelemetry::Shutdown() {
     mTimer->Cancel();
   }
 
-  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
-  MOZ_RELEASE_ASSERT(obs);
-
-  obs->RemoveObserver(this, kTopicShutdown);
-
   sInstance = nullptr;
 
   return NS_OK;
@@ -587,14 +569,3 @@ nsresult MemoryTelemetry::FinishGatheringTotalMemory(
 
   return total;
 }
-
-nsresult MemoryTelemetry::Observe(nsISupports* aSubject, const char* aTopic,
-                                  const char16_t* aData) {
-  if (strcmp(aTopic, kTopicShutdown) == 0) {
-    if (nsCOMPtr<nsITelemetry> telemetry =
-            do_GetService("@mozilla.org/base/telemetry;1")) {
-      telemetry->FlushBatchedChildTelemetry();
-    }
-  }
-  return NS_OK;
-}
diff --git a/xpcom/base/MemoryTelemetry.h b/xpcom/base/MemoryTelemetry.h
@@ -10,7 +10,6 @@
 #include "mozilla/TimeStamp.h"
 #include "mozilla/Maybe.h"
 #include "mozilla/Result.h"
-#include "nsIObserver.h"
 #include "nsITimer.h"
 #include "nsTArray.h"
 #include "nsWeakReference.h"
@@ -31,11 +30,9 @@ enum class ResponseRejectReason;
  * Periodically gathers memory usage metrics after cycle collection, and
  * populates telemetry histograms with their values.
  */
-class MemoryTelemetry final : public nsIObserver,
-                              public nsSupportsWeakReference {
+class MemoryTelemetry final : public nsSupportsWeakReference {
  public:
   NS_DECL_THREADSAFE_ISUPPORTS
-  NS_DECL_NSIOBSERVER
 
   static RefPtr<MemoryTelemetry> Create();
 
@@ -62,8 +59,6 @@ class MemoryTelemetry final : public nsIObserver,
 
   ~MemoryTelemetry() = default;
 
-  void Init();
-
   static Result<uint32_t, nsresult> GetOpenTabsCount();
 
   void GatherTotalMemory();