Add RenderFrameHostImpl.DroppedInterfaceRequestName.

Interface requests to RenderFrame::GetRemoteInterfaces are dropped when
they arrive to the RenderFrameHostImpl after the RenderFrameHostImpl had
already committed the next cross-document navigation.

In follow-up to crrev.com/c/974263, this CL adds a histogram to record,
for each load, and for each dropped Mojo interface request in a frame, a
sample with a value corresponding to the hash of the dropped interface's
name, calculated as the lower 31 bits of the base::HashMetricName(name).

Bug: 795258
Change-Id: I0a4a3aa552c4bc2eb543b4aad3a3a35ecae9f831
Reviewed-on: https://chromium-review.googlesource.com/993059Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Ken Rockot <rockot@chromium.org>
Reviewed-by: Nasko Oskov <nasko@chromium.org>
Commit-Queue: Balazs Engedy <engedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549505}

content/browser/frame_host/render_frame_host_impl.cc

@@ -15,8 +15,11 @@
 #include "base/lazy_instance.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
+#include "base/metrics/histogram_functions.h"
 #include "base/metrics/histogram_macros.h"
+#include "base/metrics/metrics_hashes.h"
 #include "base/metrics/user_metrics.h"
+#include "base/numerics/safe_conversions.h"
 #include "base/process/kill.h"
 #include "base/task_scheduler/post_task.h"
 #include "base/time/time.h"
@@ -377,6 +380,13 @@ bool IsOutOfProcessNetworkService() {
              switches::kSingleProcess);
 }
 
+// Takes the lower 31 bits of the metric-name-hash of a Mojo interface |name|.
+base::Histogram::Sample HashInterfaceNameToHistogramSample(
+    base::StringPiece name) {
+  return base::strict_cast<base::Histogram::Sample>(
+      static_cast<int32_t>(base::HashMetricName(name) & 0x7fffffffull));
+}
+
 }  // namespace
 
 RenderFrameHostImpl::PendingNavigation::PendingNavigation(
@@ -397,6 +407,7 @@ class RenderFrameHostImpl::DroppedInterfaceRequestLogger
       : binding_(this) {
     binding_.Bind(std::move(request));
   }
+
   ~DroppedInterfaceRequestLogger() override {
     UMA_HISTOGRAM_EXACT_LINEAR("RenderFrameHostImpl.DroppedInterfaceRequests",
                                num_dropped_requests_, 20);
@@ -407,6 +418,9 @@ class RenderFrameHostImpl::DroppedInterfaceRequestLogger
   void GetInterface(const std::string& interface_name,
                     mojo::ScopedMessagePipeHandle pipe) override {
     ++num_dropped_requests_;
+    base::UmaHistogramSparse(
+        "RenderFrameHostImpl.DroppedInterfaceRequestName",
+        HashInterfaceNameToHistogramSample(interface_name));
     DLOG(WARNING)
         << "InterfaceRequest was dropped, the document is no longer active: "
         << interface_name;

content/browser/frame_host/render_frame_host_impl_browsertest.cc

@@ -1315,6 +1315,9 @@ IN_PROC_BROWSER_TEST_F(RenderFrameHostImplBrowserTest,
   const GURL kUrl3(embedded_test_server()->GetURL("/title3.html"));
   const GURL kUrl4(embedded_test_server()->GetURL("/empty.html"));
 
+  // The 31-bit hash of the string "content::mojom::BrowserTarget".
+  const int32_t kHashOfContentMojomBrowserTarget = 0x1CA01D37;
+
   // Client ends of the fake interface provider requests injected for the first
   // and second navigations.
   service_manager::mojom::InterfaceProviderPtr interface_provider_1;
@@ -1359,6 +1362,9 @@ IN_PROC_BROWSER_TEST_F(RenderFrameHostImplBrowserTest,
     ASSERT_TRUE(NavigateToURL(shell(), kUrl3));
     histogram_tester.ExpectUniqueSample(
         "RenderFrameHostImpl.DroppedInterfaceRequests", 2, 1);
+    histogram_tester.ExpectUniqueSample(
+        "RenderFrameHostImpl.DroppedInterfaceRequestName",
+        kHashOfContentMojomBrowserTarget, 2);
   }
 
   // Simulate one interface request dropped for the second URL.
@@ -1371,6 +1377,9 @@ IN_PROC_BROWSER_TEST_F(RenderFrameHostImplBrowserTest,
     ASSERT_TRUE(NavigateToURL(shell(), kUrl4));
     histogram_tester.ExpectUniqueSample(
         "RenderFrameHostImpl.DroppedInterfaceRequests", 1, 1);
+    histogram_tester.ExpectUniqueSample(
+        "RenderFrameHostImpl.DroppedInterfaceRequestName",
+        kHashOfContentMojomBrowserTarget, 1);
   }
 
   // Both the DroppedInterfaceRequestLogger for the first and second URLs are

tools/metrics/histograms/enums.xml

@@ -38336,6 +38336,72 @@ Called by update_net_trust_anchors.py.-->
   <int value="6" label="While closing the page"/>
 </enum>
 
+<enum name="RenderFrameHostImpl.InterfaceNames">
+  <summary>
+    Enumerates names of Mojo interfaces that are requests through
+    RenderFrameHostImpl::GetInterface.
+  </summary>
+  <int value="39256405" label="device::mojom::Geolocation"/>
+  <int value="81966276" label="blink::mojom::KeyboardLockService"/>
+  <int value="112672197" label="content::mojom::SharedWorkerConnector"/>
+  <int value="141486647" label="webauth::mojom::Authenticator"/>
+  <int value="155545232" label="blink::mojom::GeolocationService"/>
+  <int value="188516542" label="content::mojom::MediaStreamDispatcherHost"/>
+  <int value="190256703" label="network::mojom::RestrictedCookieManager"/>
+  <int value="264532149" label="blink::mojom::LockManager"/>
+  <int value="298400659" label="media::mojom::MediaMetricsProvider"/>
+  <int value="473587909" label="autofill::mojom::AutofillDriver"/>
+  <int value="480255287" label="content::mojom::BrowserTarget"/>
+  <int value="583861320" label="media::mojom::InterfaceFactory"/>
+  <int value="593735191" label="blink::mojom::PresentationService"/>
+  <int value="620853817" label="media::mojom::Renderer"/>
+  <int value="670026296" label="blink::mojom::CacheStorage"/>
+  <int value="803397464" label="device::mojom::UsbDeviceManager"/>
+  <int value="833468074" label="device::mojom::VRService"/>
+  <int value="846414148" label="blink::mojom::MediaDevicesDispatcherHost"/>
+  <int value="917382314" label="blink::mojom::TextSuggestionHost"/>
+  <int value="917568449" label="media::mojom::ImageCapture"/>
+  <int value="968027799" label="blink::mojom::MediaSessionService"/>
+  <int value="996732224" label="autofill::mojom::PasswordManagerDriver"/>
+  <int value="1071268620" label="blink::mojom::QuotaDispatcherHost"/>
+  <int value="1116085333"
+      label="content::mojom::RendererAudioOutputStreamFactory"/>
+  <int value="1144778719" label="ui::mojom::Gpu"/>
+  <int value="1214902026" label="device::mojom::VibrationManager"/>
+  <int value="1237802022" label="blink::mojom::PermissionService"/>
+  <int value="1298636847" label="media::mojom::RemoterFactory"/>
+  <int value="1321671191" label="blink::mojom::BudgetService"/>
+  <int value="1337066913"
+      label="resource_coordinator::mojom::FrameCoordinationUnit"/>
+  <int value="1374541190" label="payments::mojom::PaymentManager"/>
+  <int value="1416694600" label="payments::mojom::PaymentRequest"/>
+  <int value="1419976867" label="blink::mojom::DedicatedWorkerFactory"/>
+  <int value="1448556545" label="content::mojom::InputInjector"/>
+  <int value="1548931182"
+      label="shape_detection::mojom::FaceDetectionProvider"/>
+  <int value="1558900994" label="device::mojom::NFC"/>
+  <int value="1608786055" label="network::mojom::WebSocket"/>
+  <int value="1658893493" label="device::mojom::WakeLock"/>
+  <int value="1659485640" label="password_manager::mojom::CredentialManager"/>
+  <int value="1725898486" label="blink::mojom::UnhandledTapNotifier"/>
+  <int value="1726661029" label="blink::mojom::ColorChooserFactory"/>
+  <int value="1727086043"
+      label="content::mojom::RendererAudioInputStreamFactory"/>
+  <int value="1729889736"
+      label="discardable_memory::mojom::DiscardableSharedMemoryManager"/>
+  <int value="1737293395" label="device::mojom::UsbChooserService"/>
+  <int value="1750772802" label="blink::mojom::NotificationService"/>
+  <int value="1769429998" label="blink::mojom::PrefetchURLLoaderService"/>
+  <int value="1785235899" label="shape_detection::mojom::BarcodeDetection"/>
+  <int value="1798060917" label="blink::mojom::BackgroundFetchService"/>
+  <int value="1851878773" label="blink::mojom::WebBluetoothService"/>
+  <int value="1951066980" label="shape_detection::mojom::TextDetection"/>
+  <int value="2060513738"
+      label="webauth::test::mojom::VirtualAuthenticatorManager"/>
+  <int value="2067597900" label="blink::mojom::InsecureInputService"/>
+  <int value="2109171099" label="device::mojom::SensorProvider"/>
+</enum>
+
 <enum name="RenderViewContextMenuItem">
   <int value="0" label="IDC_CONTENT_CONTEXT_CUSTOM_FIRST"/>
   <int value="1" label="IDC_EXTENSIONS_CONTEXT_CUSTOM_FIRST"/>

tools/metrics/histograms/histograms.xml

@@ -74674,6 +74674,25 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="RenderFrameHostImpl.DroppedInterfaceRequestName"
+    enum="RenderFrameHostImpl.InterfaceNames">
+  <owner>engedy@chromium.org</owner>
+  <summary>
+    For each load and dropped Mojo interface request in a frame, records a
+    sample with a value corresponding to the hash of the interface name,
+    calculated as the lower 31 bits of the interface name's metric name hash.
+
+    Interface requests to RenderFrame::GetRemoteInterfaces are dropped when they
+    arrive to the RenderFrameHostImpl after the RenderFrameHostImpl had already
+    committed the next cross-document navigation.
+
+    This means that |document_scoped_interface_provider_binding_| was already
+    unbound at the time from the interface connection that had been used to
+    service RenderFrame::GetRemoteInterface for the previous load, so those
+    interface requests are dropped.
+  </summary>
+</histogram>
+
 <histogram name="RenderFrameHostImpl.DroppedInterfaceRequests" units="count">
   <owner>engedy@chromium.org</owner>
   <summary>