1 files changed, 236 insertions, 0 deletions
diff --git a/ipc/mscom/ProfilerMarkers.cpp b/ipc/mscom/ProfilerMarkers.cpp
new file mode 100644
index 0000000000..29d033723f
--- /dev/null
+++ b/ipc/mscom/ProfilerMarkers.cpp
@@ -0,0 +1,236 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ProfilerMarkers.h"
+
+#include "MainThreadUtils.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Atomics.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/mscom/Utils.h"
+#include "mozilla/ProfilerMarkers.h"
+#include "mozilla/Services.h"
+#include "nsCOMPtr.h"
+#include "nsIObserver.h"
+#include "nsIObserverService.h"
+#include "nsISupportsImpl.h"
+#include "nsString.h"
+#include "nsXULAppAPI.h"
+
+#include <objbase.h>
+#include <objidlbase.h>
+
+// {9DBE6B28-E5E7-4FDE-AF00-9404604E74DC}
+static const GUID GUID_MozProfilerMarkerExtension = {
+    0x9dbe6b28, 0xe5e7, 0x4fde, {0xaf, 0x0, 0x94, 0x4, 0x60, 0x4e, 0x74, 0xdc}};
+
+namespace {
+
+class ProfilerMarkerChannelHook final : public IChannelHook {
+  ~ProfilerMarkerChannelHook() = default;
+
+ public:
+  ProfilerMarkerChannelHook() : mRefCnt(0) {}
+
+  // IUnknown
+  STDMETHODIMP QueryInterface(REFIID aIid, void** aOutInterface) override;
+  STDMETHODIMP_(ULONG) AddRef() override;
+  STDMETHODIMP_(ULONG) Release() override;
+
+  /**
+   * IChannelHook exposes six methods: The Client* methods are called when
+   * a client is sending an IPC request, whereas the Server* methods are called
+   * when a server is receiving an IPC request.
+   *
+   * For our purposes, we only care about the client-side methods. The COM
+   * runtime invokes the methods in the following order:
+   * 1. ClientGetSize, where the hook specifies the size of its payload;
+   * 2. ClientFillBuffer, where the hook fills the channel's buffer with its
+   *    payload information. NOTE: This method is only called when ClientGetSize
+   *    specifies a non-zero payload size. For our purposes, since we are not
+   *    sending a payload, this method will never be called!
+   * 3. ClientNotify, when the response has been received from the server.
+   *
+   * Since we want to use these hooks to record the beginning and end of a COM
+   * IPC call, we use ClientGetSize for logging the start, and ClientNotify for
+   * logging the end.
+   *
+   * Finally, our implementation responds to any request matching our extension
+   * ID, however we only care about main thread COM calls.
+   */
+
+  // IChannelHook
+  STDMETHODIMP_(void)
+  ClientGetSize(REFGUID aExtensionId, REFIID aIid,
+                ULONG* aOutDataSize) override;
+
+  // No-op (see the large comment above)
+  STDMETHODIMP_(void)
+  ClientFillBuffer(REFGUID aExtensionId, REFIID aIid, ULONG* aDataSize,
+                   void* aDataBuf) override {}
+
+  STDMETHODIMP_(void)
+  ClientNotify(REFGUID aExtensionId, REFIID aIid, ULONG aDataSize,
+               void* aDataBuffer, DWORD aDataRep, HRESULT aFault) override;
+
+  // We don't care about the server-side notifications, so leave as no-ops.
+  STDMETHODIMP_(void)
+  ServerNotify(REFGUID aExtensionId, REFIID aIid, ULONG aDataSize,
+               void* aDataBuf, DWORD aDataRep) override {}
+
+  STDMETHODIMP_(void)
+  ServerGetSize(REFGUID aExtensionId, REFIID aIid, HRESULT aFault,
+                ULONG* aOutDataSize) override {}
+
+  STDMETHODIMP_(void)
+  ServerFillBuffer(REFGUID aExtensionId, REFIID aIid, ULONG* aDataSize,
+                   void* aDataBuf, HRESULT aFault) override {}
+
+ private:
+  void BuildMarkerName(REFIID aIid, nsACString& aOutMarkerName);
+
+ private:
+  mozilla::Atomic<ULONG> mRefCnt;
+};
+
+HRESULT ProfilerMarkerChannelHook::QueryInterface(REFIID aIid,
+                                                  void** aOutInterface) {
+  if (aIid == IID_IChannelHook || aIid == IID_IUnknown) {
+    RefPtr<IChannelHook> ptr(this);
+    ptr.forget(aOutInterface);
+    return S_OK;
+  }
+
+  return E_NOINTERFACE;
+}
+
+ULONG ProfilerMarkerChannelHook::AddRef() { return ++mRefCnt; }
+
+ULONG ProfilerMarkerChannelHook::Release() {
+  ULONG result = --mRefCnt;
+  if (!result) {
+    delete this;
+  }
+
+  return result;
+}
+
+void ProfilerMarkerChannelHook::BuildMarkerName(REFIID aIid,
+                                                nsACString& aOutMarkerName) {
+  aOutMarkerName.AssignLiteral("ORPC Call for ");
+
+  nsAutoCString iidStr;
+  mozilla::mscom::DiagnosticNameForIID(aIid, iidStr);
+  aOutMarkerName.Append(iidStr);
+}
+
+void ProfilerMarkerChannelHook::ClientGetSize(REFGUID aExtensionId, REFIID aIid,
+                                              ULONG* aOutDataSize) {
+  if (aExtensionId == GUID_MozProfilerMarkerExtension) {
+    if (NS_IsMainThread()) {
+      nsAutoCString markerName;
+      BuildMarkerName(aIid, markerName);
+      PROFILER_MARKER(markerName, IPC, mozilla::MarkerTiming::IntervalStart(),
+                      Tracing, "MSCOM");
+    }
+
+    if (aOutDataSize) {
+      // We don't add any payload data to the channel
+      *aOutDataSize = 0UL;
+    }
+  }
+}
+
+void ProfilerMarkerChannelHook::ClientNotify(REFGUID aExtensionId, REFIID aIid,
+                                             ULONG aDataSize, void* aDataBuffer,
+                                             DWORD aDataRep, HRESULT aFault) {
+  if (NS_IsMainThread() && aExtensionId == GUID_MozProfilerMarkerExtension) {
+    nsAutoCString markerName;
+    BuildMarkerName(aIid, markerName);
+    PROFILER_MARKER(markerName, IPC, mozilla::MarkerTiming::IntervalEnd(),
+                    Tracing, "MSCOM");
+  }
+}
+
+}  // anonymous namespace
+
+static void RegisterChannelHook() {
+  RefPtr<ProfilerMarkerChannelHook> hook(new ProfilerMarkerChannelHook());
+  mozilla::DebugOnly<HRESULT> hr =
+      ::CoRegisterChannelHook(GUID_MozProfilerMarkerExtension, hook);
+  MOZ_ASSERT(SUCCEEDED(hr));
+}
+
+namespace {
+
+class ProfilerStartupObserver final : public nsIObserver {
+  ~ProfilerStartupObserver() = default;
+
+ public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIOBSERVER
+};
+
+NS_IMPL_ISUPPORTS(ProfilerStartupObserver, nsIObserver)
+
+NS_IMETHODIMP ProfilerStartupObserver::Observe(nsISupports* aSubject,
+                                               const char* aTopic,
+                                               const char16_t* aData) {
+  if (strcmp(aTopic, "profiler-started")) {
+    return NS_OK;
+  }
+
+  RegisterChannelHook();
+
+  // Once we've set the channel hook, we don't care about this notification
+  // anymore; our channel hook will remain set for the lifetime of the process.
+  nsCOMPtr<nsIObserverService> obsServ(mozilla::services::GetObserverService());
+  MOZ_ASSERT(!!obsServ);
+  if (!obsServ) {
+    return NS_OK;
+  }
+
+  obsServ->RemoveObserver(this, "profiler-started");
+  return NS_OK;
+}
+
+}  // anonymous namespace
+
+namespace mozilla {
+namespace mscom {
+
+void InitProfilerMarkers() {
+  if (!XRE_IsParentProcess()) {
+    return;
+  }
+
+  MOZ_ASSERT(NS_IsMainThread());
+  if (!NS_IsMainThread()) {
+    return;
+  }
+
+  if (profiler_is_active()) {
+    // If the profiler is already running, we'll immediately register our
+    // channel hook.
+    RegisterChannelHook();
+    return;
+  }
+
+  // The profiler is not running yet. To avoid unnecessary invocations of the
+  // channel hook, we won't bother with installing it until the profiler starts.
+  // Set up an observer to watch for this.
+  nsCOMPtr<nsIObserverService> obsServ(mozilla::services::GetObserverService());
+  MOZ_ASSERT(!!obsServ);
+  if (!obsServ) {
+    return;
+  }
+
+  nsCOMPtr<nsIObserver> obs(new ProfilerStartupObserver());
+  obsServ->AddObserver(obs, "profiler-started", false);
+}
+
+}  // namespace mscom
+}  // namespace mozilla