bug 1470853 - Add Telemetry::DNS_TRR_REQUEST_PER_CONN r=nwgh

Count number of requests/streams per connection done when the connection
was used for TRR.

MozReview-Commit-ID: H7X06h8gVZY

Differential Revision: https://phabricator.services.mozilla.com/D3589

--HG--
extra : moz-landing-system : lando

netwerk/protocol/http/Http2Session.cpp

@@ -121,6 +121,7 @@ Http2Session::Http2Session(nsISocketTransport *aSocketTransport, enum SpdyVersio
   , mTlsHandshakeFinished(false)
   , mCheckNetworkStallsWithTFO(false)
   , mLastRequestBytesSentTime(0)
+  , mTrrStreams(0)
 {
   MOZ_ASSERT(OnSocketThread(), "not on socket thread");
 
@@ -179,6 +180,9 @@ Http2Session::~Http2Session()
 
   Shutdown();
 
+  if (mTrrStreams) {
+    Telemetry::Accumulate(Telemetry::DNS_TRR_REQUEST_PER_CONN, mTrrStreams);
+  }
   Telemetry::Accumulate(Telemetry::SPDY_PARALLEL_STREAMS, mConcurrentHighWater);
   Telemetry::Accumulate(Telemetry::SPDY_REQUEST_PER_CONN, (mNextStreamID - 1) / 2);
   Telemetry::Accumulate(Telemetry::SPDY_SERVER_INITIATED_STREAMS,
@@ -400,6 +404,13 @@ Http2Session::RegisterStreamID(Http2Stream *stream, uint32_t aNewID)
       mLastRequestBytesSentTime = PR_IntervalNow();
     }
   }
+
+  MOZ_ASSERT(stream->Transaction(), "no transation for the stream!");
+  RefPtr<nsHttpConnectionInfo> ci(stream->Transaction()->ConnectionInfo());
+  if (ci && ci->GetTrrUsed()) {
+    mTrrStreams++;
+  }
+
   return aNewID;
 }
 

netwerk/protocol/http/Http2Session.h

@@ -574,6 +574,7 @@ private:
   void UnRegisterTunnel(Http2Stream *);
   uint32_t FindTunnelCount(nsHttpConnectionInfo *);
   nsDataHashtable<nsCStringHashKey, uint32_t> mTunnelHash;
+  uint32_t mTrrStreams;
 };
 
 } // namespace net

netwerk/protocol/http/nsHttpChannel.cpp

@@ -571,6 +571,7 @@ nsHttpChannel::OnBeforeConnect()
     mConnectionInfo->SetNoSpdy(mCaps & NS_HTTP_DISALLOW_SPDY);
     mConnectionInfo->SetBeConservative((mCaps & NS_HTTP_BE_CONSERVATIVE) || mBeConservative);
     mConnectionInfo->SetTlsFlags(mTlsFlags);
+    mConnectionInfo->SetTrrUsed(mTRR);
 
     // notify "http-on-before-connect" observers
     gHttpHandler->OnBeforeConnect(this);

netwerk/protocol/http/nsHttpConnection.cpp

@@ -123,6 +123,19 @@ nsHttpConnection::~nsHttpConnection()
              this, mHttp1xTransactionCount));
         Telemetry::Accumulate(Telemetry::HTTP_REQUEST_PER_CONN,
                               mHttp1xTransactionCount);
+        nsHttpConnectionInfo *ci = nullptr;
+        if (mTransaction) {
+            ci = mTransaction->ConnectionInfo();
+        }
+        if (!ci) {
+            ci = mConnInfo;
+        }
+
+        MOZ_ASSERT(ci);
+        if (ci->GetTrrUsed()) {
+            Telemetry::Accumulate(Telemetry::DNS_TRR_REQUEST_PER_CONN,
+                                  mHttp1xTransactionCount);
+        }
     }
 
     if (mTotalBytesRead) {

netwerk/protocol/http/nsHttpConnectionInfo.cpp

@@ -89,6 +89,7 @@ nsHttpConnectionInfo::Init(const nsACString &host, int32_t port,
     mNPNToken = npnToken;
     mOriginAttributes = originAttributes;
     mTlsFlags = 0x0;
+    mTrrUsed = false;
 
     mUsingHttpsProxy = (proxyInfo && proxyInfo->IsHTTPS());
     mUsingHttpProxy = mUsingHttpsProxy || (proxyInfo && proxyInfo->IsHTTP());
@@ -242,6 +243,7 @@ nsHttpConnectionInfo::Clone() const
     clone->SetNoSpdy(GetNoSpdy());
     clone->SetBeConservative(GetBeConservative());
     clone->SetTlsFlags(GetTlsFlags());
+    clone->SetTrrUsed(GetTrrUsed());
     MOZ_ASSERT(clone->Equals(this));
 
     return clone;

netwerk/protocol/http/nsHttpConnectionInfo.h

@@ -120,6 +120,9 @@ public:
     void          SetTlsFlags(uint32_t aTlsFlags);
     uint32_t      GetTlsFlags() const { return mTlsFlags; }
 
+    void          SetTrrUsed(bool aUsed) { mTrrUsed = aUsed; }
+    bool          GetTrrUsed() const { return mTrrUsed; }
+
     const nsCString &GetNPNToken() { return mNPNToken; }
     const nsCString &GetUsername() { return mUsername; }
 
@@ -172,6 +175,7 @@ private:
     OriginAttributes       mOriginAttributes;
 
     uint32_t               mTlsFlags;
+    uint16_t               mTrrUsed : 1;
 
 // for RefPtr
     NS_INLINE_DECL_THREADSAFE_REFCOUNTING(nsHttpConnectionInfo, override)

toolkit/components/telemetry/Histograms.json

@@ -3330,6 +3330,16 @@
     "bug_numbers": [1453825],
     "alert_emails": ["necko@mozilla.com", "dstenberg@mozilla.com"]
   },
+  "DNS_TRR_REQUEST_PER_CONN": {
+    "record_in_processes": ["main", "content"],
+    "alert_emails": ["necko@mozilla.com", "dstenberg@mozilla.com"],
+    "expires_in_version": "never",
+    "kind": "exponential",
+    "high": 5000,
+    "n_buckets": 100,
+    "bug_numbers": [1470853],
+    "description": "Number of DOH requests per connection"
+  },
   "DNS_LOOKUP_ALGORITHM": {
     "record_in_processes": ["main"],
     "alert_emails": ["necko@mozilla.com", "dstenberg@mozilla.com"],