From 3d66c37e7682107bfe34de575088d618f7c76fe1 Mon Sep 17 00:00:00 2001
From: Kershaw Chang <kershaw@mozilla.com>
Date: Thu, 18 Feb 2021 12:50:04 +0000
Subject: [PATCH] Bug 1689987 - P5: Add probes to collect DNS lookup time when
 ODoH is used r=necko-reviewers,valentin

Differential Revision: https://phabricator.services.mozilla.com/D105215
---
 netwerk/base/nsLoadGroup.cpp                 | 17 +++++++++++++++
 toolkit/components/telemetry/Histograms.json | 22 ++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/netwerk/base/nsLoadGroup.cpp b/netwerk/base/nsLoadGroup.cpp
index ea8acb73cb1a..1442eb9fd04e 100644
--- a/netwerk/base/nsLoadGroup.cpp
+++ b/netwerk/base/nsLoadGroup.cpp
@@ -968,6 +968,23 @@ void nsLoadGroup::TelemetryReportChannel(nsITimedChannel* aTimedChannel,
     }
   }
 
+  if (StaticPrefs::network_trr_odoh_enabled() && !domainLookupStart.IsNull() &&
+      !domainLookupEnd.IsNull()) {
+    nsCOMPtr<nsIDNSService> dns = do_GetService(NS_DNSSERVICE_CONTRACTID);
+    bool ODoHActivated = false;
+    if (dns && NS_SUCCEEDED(dns->GetODoHActivated(&ODoHActivated)) &&
+        ODoHActivated) {
+      if (aDefaultRequest) {
+        Telemetry::AccumulateTimeDelta(
+            Telemetry::HTTP_PAGE_DNS_ODOH_LOOKUP_TIME, domainLookupStart,
+            domainLookupEnd);
+      } else {
+        Telemetry::AccumulateTimeDelta(Telemetry::HTTP_SUB_DNS_ODOH_LOOKUP_TIME,
+                                       domainLookupStart, domainLookupEnd);
+      }
+    }
+  }
+
 #undef HTTP_REQUEST_HISTOGRAMS
 }
 
diff --git a/toolkit/components/telemetry/Histograms.json b/toolkit/components/telemetry/Histograms.json
index 2530d10d1c0a..fad57c56dc58 100644
--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -16468,5 +16468,27 @@
     "bug_numbers": [1689987],
     "releaseChannelCollection": "opt-out",
     "description": "When in ODoH-first mode, it lists the reason we may have skipped ODoH"
+  },
+  "HTTP_PAGE_DNS_ODOH_LOOKUP_TIME": {
+    "record_in_processes": ["main", "content"],
+    "products": ["firefox"],
+    "expires_in_version": "never",
+    "alert_emails": ["necko@mozilla.com", "kershaw@mozilla.com"],
+    "kind": "exponential",
+    "high": 30000,
+    "n_buckets": 50,
+    "description": "HTTP page channel: ODoH lookup time (ms)",
+    "bug_numbers": [1689987]
+  },
+  "HTTP_SUB_DNS_ODOH_LOOKUP_TIME": {
+    "record_in_processes": ["main", "content"],
+    "products": ["firefox"],
+    "expires_in_version": "never",
+    "kind": "exponential",
+    "high": 30000,
+    "n_buckets": 50,
+    "bug_numbers": [1689987],
+    "alert_emails": ["necko@mozilla.com", "kershaw@mozilla.com"],
+    "description": "HTTP subitem channel: ODoH lookup time (ms)"
   }
 }