Bug 1796639 - Add telemetry for first contentful paint keyed by TRR provider r=necko-reviewers,valentin

We are interested in the user-experienced performance based on the TRR (if any).

Differential Revision: https://phabricator.services.mozilla.com/D160569

dom/base/Document.cpp

@@ -248,6 +248,7 @@
 #include "mozilla/ipc/IdleSchedulerChild.h"
 #include "mozilla/ipc/MessageChannel.h"
 #include "mozilla/net/ChannelEventQueue.h"
+#include "mozilla/net/ChildDNSService.h"
 #include "mozilla/net/CookieJarSettings.h"
 #include "mozilla/net/NeckoChannelParams.h"
 #include "mozilla/net/RequestContextService.h"
@@ -2081,11 +2082,20 @@ void Document::AccumulatePageLoadTelemetry(
     return;
   }
 
-  nsCString http3Key;
-  nsCString http3WithPriorityKey;
+  nsAutoCString dnsKey("Native");
+  nsAutoCString http3Key;
+  nsAutoCString http3WithPriorityKey;
   nsCOMPtr<nsIHttpChannelInternal> httpChannel =
       do_QueryInterface(GetChannel());
   if (httpChannel) {
+    bool resolvedByTRR = false;
+    Unused << httpChannel->GetIsResolvedByTRR(&resolvedByTRR);
+    if (resolvedByTRR) {
+      RefPtr<net::ChildDNSService> dnsServiceChild =
+          net::ChildDNSService::GetSingleton();
+      dnsServiceChild->GetTRRDomain(dnsKey);
+    }
+
     uint32_t major;
     uint32_t minor;
     if (NS_SUCCEEDED(httpChannel->GetResponseVersion(&major, &minor))) {
@@ -2131,6 +2141,10 @@ void Document::AccumulatePageLoadTelemetry(
           navigationStart, firstContentfulComposite);
     }
 
+    Telemetry::AccumulateTimeDelta(
+        Telemetry::DNS_PERF_FIRST_CONTENTFUL_PAINT_MS, dnsKey, navigationStart,
+        firstContentfulComposite);
+
     Telemetry::AccumulateTimeDelta(
         Telemetry::PERF_FIRST_CONTENTFUL_PAINT_FROM_RESPONSESTART_MS,
         responseStart, firstContentfulComposite);

dom/ipc/ContentChild.cpp

@@ -113,6 +113,7 @@
 #include "mozilla/loader/ScriptCacheActors.h"
 #include "mozilla/media/MediaChild.h"
 #include "mozilla/net/CaptivePortalService.h"
+#include "mozilla/net/ChildDNSService.h"
 #include "mozilla/net/CookieServiceChild.h"
 #include "mozilla/net/DocumentChannelChild.h"
 #include "mozilla/net/HttpChannelChild.h"
@@ -685,7 +686,11 @@ mozilla::ipc::IPCResult ContentChild::RecvSetXPCOMProcessAttributes(
   InitXPCOM(std::move(aXPCOMInit), aInitialData,
             aIsReadyForBackgroundProcessing);
   InitGraphicsDeviceData(aXPCOMInit.contentDeviceData());
-
+  RefPtr<net::ChildDNSService> dnsServiceChild =
+      dont_AddRef(net::ChildDNSService::GetSingleton());
+  if (dnsServiceChild) {
+    dnsServiceChild->SetTRRDomain(aXPCOMInit.trrDomain());
+  }
   return IPC_OK();
 }
 

dom/ipc/ContentParent.cpp

@@ -53,6 +53,8 @@
 #include "mozilla/ipc/URIUtils.h"
 #include "gfxPlatform.h"
 #include "gfxPlatformFontList.h"
+#include "nsDNSService2.h"
+#include "nsPIDNSService.h"
 #include "mozilla/AntiTrackingUtils.h"
 #include "mozilla/AppShutdown.h"
 #include "mozilla/AutoRestore.h"
@@ -163,6 +165,7 @@
 #include "mozilla/net/NeckoParent.h"
 #include "mozilla/net/PCookieServiceParent.h"
 #include "mozilla/net/CookieKey.h"
+#include "mozilla/net/TRRService.h"
 #include "mozilla/TelemetryComms.h"
 #include "mozilla/TelemetryEventEnums.h"
 #include "mozilla/RemoteLazyInputStreamParent.h"
@@ -3086,6 +3089,8 @@ bool ContentParent::InitInternal(ProcessPriority aInitialPriority) {
 
   xpcomInit.perfStatsMask() = PerfStats::GetCollectionMask();
 
+  xpcomInit.trrDomain() = TRRService::ProviderKey();
+
   Unused << SendSetXPCOMProcessAttributes(
       xpcomInit, initialData, lnf, fontList, std::move(sharedUASheetHandle),
       sharedUASheetAddress, std::move(sharedFontListBlocks),

dom/ipc/PContent.ipdl

@@ -364,6 +364,7 @@ struct XPCOMInitData
     L10nFileSourceDescriptor[] l10nFileSources;
     DynamicScalarDefinition[] dynamicScalarDefs;
     MetricMask perfStatsMask;
+    nsCString trrDomain;
 };
 
 struct VisitedQueryResult

dom/ipc/moz.build

@@ -206,6 +206,7 @@ LOCAL_INCLUDES += [
     "/layout/base",
     "/media/webrtc",
     "/netwerk/base",
+    "/netwerk/dns",
     "/netwerk/protocol/http",
     "/toolkit/components/printingui/ipc",
     "/toolkit/crashreporter",

netwerk/dns/ChildDNSService.cpp

@@ -460,5 +460,13 @@ ChildDNSService::Observe(nsISupports* subject, const char* topic,
   return NS_OK;
 }
 
+void ChildDNSService::SetTRRDomain(const nsACString& aTRRDomain) {
+  mTRRDomain = aTRRDomain;
+}
+
+void ChildDNSService::GetTRRDomain(nsACString& aTRRDomain) {
+  aTRRDomain = mTRRDomain;
+}
+
 }  // namespace net
 }  // namespace mozilla

netwerk/dns/ChildDNSService.h

@@ -35,6 +35,9 @@ class ChildDNSService final : public DNSServiceBase, public nsPIDNSService {
 
   void NotifyRequestDone(DNSRequestSender* aDnsRequest);
 
+  void SetTRRDomain(const nsACString& aTRRDomain);
+  void GetTRRDomain(nsACString& aTRRDomain);
+
  private:
   virtual ~ChildDNSService() = default;
 
@@ -60,6 +63,8 @@ class ChildDNSService final : public DNSServiceBase, public nsPIDNSService {
       mPendingRequests;
   Mutex mPendingRequestsLock MOZ_UNANNOTATED{"DNSPendingRequestsLock"};
   RefPtr<TRRServiceParent> mTRRServiceParent;
+
+  nsCString mTRRDomain;
 };
 
 }  // namespace net

netwerk/dns/TRRService.cpp

@@ -23,6 +23,8 @@
 #include "mozilla/Telemetry.h"
 #include "mozilla/TelemetryComms.h"
 #include "mozilla/Tokenizer.h"
+#include "mozilla/dom/ContentParent.h"
+#include "mozilla/net/NeckoParent.h"
 #include "mozilla/net/TRRServiceChild.h"
 // Put DNSLogging.h at the end to avoid LOG being overwritten by other headers.
 #include "DNSLogging.h"
@@ -300,6 +302,17 @@ bool TRRService::MaybeSetPrivateURI(const nsACString& aURI) {
 
     mPrivateURI = newURI;
 
+    // Notify the content processes of the new TRR
+    for (auto* cp :
+         dom::ContentParent::AllProcesses(dom::ContentParent::eLive)) {
+      PNeckoParent* neckoParent =
+          SingleManagedOrNull(cp->ManagedPNeckoParent());
+      if (!neckoParent) {
+        continue;
+      }
+      Unused << neckoParent->SendSetTRRDomain(ProviderKey());
+    }
+
     AsyncCreateTRRConnectionInfo(mPrivateURI);
 
     // The URI has changed. We should trigger a new confirmation immediately.

netwerk/dns/moz.build

@@ -42,6 +42,7 @@ EXPORTS.mozilla.net += [
     "DNSRequestBase.h",
     "DNSRequestChild.h",
     "DNSRequestParent.h",
+    "DNSServiceBase.h",
     "HTTPSSVC.h",
     "IDNBlocklistUtils.h",
     "NativeDNSResolverOverrideChild.h",

netwerk/ipc/NeckoChild.cpp

@@ -10,6 +10,7 @@
 #include "mozilla/dom/ContentChild.h"
 #include "mozilla/dom/BrowserChild.h"
 #include "mozilla/net/HttpChannelChild.h"
+#include "mozilla/net/ChildDNSService.h"
 #include "mozilla/net/CookieServiceChild.h"
 #include "mozilla/net/DataChannelChild.h"
 #ifdef MOZ_WIDGET_GTK
@@ -343,5 +344,14 @@ bool NeckoChild::DeallocPClassifierDummyChannelChild(
   return true;
 }
 
+mozilla::ipc::IPCResult NeckoChild::RecvSetTRRDomain(const nsCString& domain) {
+  RefPtr<net::ChildDNSService> dnsServiceChild =
+      dont_AddRef(net::ChildDNSService::GetSingleton());
+  if (dnsServiceChild) {
+    dnsServiceChild->SetTRRDomain(domain);
+  }
+  return IPC_OK();
+}
+
 }  // namespace net
 }  // namespace mozilla

netwerk/ipc/NeckoChild.h

@@ -84,6 +84,8 @@ class NeckoChild : public PNeckoChild {
 
   bool DeallocPClassifierDummyChannelChild(
       PClassifierDummyChannelChild* aActor);
+
+  mozilla::ipc::IPCResult RecvSetTRRDomain(const nsCString& domain);
 };
 
 /**

netwerk/ipc/PNecko.ipdl

@@ -166,6 +166,8 @@ child:
 
   async PTransportProvider();
 
+  async SetTRRDomain(nsCString domain);
+
 both:
   // Actually we need PTCPSocket() for parent. But ipdl disallows us having different
   // signatures on parent and child. So when constructing the parent side object, we just

toolkit/components/telemetry/Histograms.json

@@ -5243,6 +5243,19 @@
     "kind": "enumerated",
     "description": "The reason why we failed to connect with an HTTPSSVC record"
   },
+  "DNS_PERF_FIRST_CONTENTFUL_PAINT_MS": {
+    "record_in_processes": ["content"],
+    "products": ["firefox"],
+    "alert_emails": ["necko@mozilla.com", "acreskey@mozilla.com"],
+    "expires_in_version": "never",
+    "releaseChannelCollection": "opt-out",
+    "kind": "exponential",
+    "high": 50000,
+    "n_buckets": 100,
+    "bug_numbers": [1796639],
+    "keyed": true,
+    "description": "The time between navigationStart and the first contentful paint of a foreground http or https root content document, in milliseconds. The contentful paint timestamp is taken during display list building and does not include rasterization or compositing of that paint. Keyed by TRR domain for DoH or 'Native' otherwise"
+  },
   "REFRESH_DRIVER_TICK" : {
     "record_in_processes": ["main", "content"],
     "products": ["firefox", "fennec"],