The Tor Browser: xpcom/build/perfprobe.cpp@6474c204b198 (annotated)

xpcom/build/perfprobe.cpp@6474c204b198 (annotated)

xpcom/build/perfprobe.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*-  Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
 /* 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/. */
 /*****************************
  Windows implementation of probes, using xperf
  *****************************/
 #include <windows.h>
 #include <wmistr.h>
 #include <evntrace.h>
 #include "perfprobe.h"
 #include "nsAutoPtr.h"
 namespace mozilla {
 namespace probes {
 #if defined(MOZ_LOGGING)
 static PRLogModuleInfo *
 GetProbeLog()
 {
   static PRLogModuleInfo *sLog;
   if (!sLog)
     sLog = PR_NewLogModule("SysProbe");
   return sLog;
 }
 #define LOG(x)  PR_LOG(GetProbeLog(), PR_LOG_DEBUG, x)
 #else
 #define LOG(x)
 #endif
 //Utility function
 GUID CID_to_GUID(const nsCID &aCID)
 {
   GUID result;
   result.Data1 = aCID.m0;
   result.Data2 = aCID.m1;
   result.Data3 = aCID.m2;
   for (int i = 0; i < 8; ++i)
     result.Data4[i] = aCID.m3[i];
   return result;
 }
 // Implementation of Probe
 Probe::Probe(const nsCID &aGUID,
              const nsACString &aName,
              ProbeManager *aManager)
   : mGUID(CID_to_GUID(aGUID))
   , mName(aName)
   , mManager(aManager)
 {
 }
 nsresult Probe::Trigger()
 {
   if (!(mManager->mIsActive)) {
     //Do not trigger if there is no session
     return NS_OK;
   }
   _EVENT_TRACE_HEADER event;
   ZeroMemory(&event, sizeof(event));
   event.Size = sizeof(event);
   event.Flags = WNODE_FLAG_TRACED_GUID ;
   event.Guid = (const GUID)mGUID;
   event.Class.Type    = 1;
   event.Class.Version = 0;
   event.Class.Level   = TRACE_LEVEL_INFORMATION;
   ULONG result        = TraceEvent(mManager->mSessionHandle, &event);
   LOG(("Probes: Triggered %s, %s, %ld",
        mName.Data(),
        result==ERROR_SUCCESS ? "success":"failure",
        result));
   nsresult rv;
   switch(result)
   {
     case ERROR_SUCCESS:             rv = NS_OK; break;
     case ERROR_INVALID_FLAG_NUMBER:
     case ERROR_MORE_DATA:
     case ERROR_INVALID_PARAMETER:   rv = NS_ERROR_INVALID_ARG; break;
     case ERROR_INVALID_HANDLE:      rv = NS_ERROR_FAILURE;     break;
     case ERROR_NOT_ENOUGH_MEMORY:
     case ERROR_OUTOFMEMORY:         rv = NS_ERROR_OUT_OF_MEMORY; break;
     default:                        rv = NS_ERROR_UNEXPECTED;
   }
   return rv;
 }
 // Implementation of ProbeManager
 ProbeManager::~ProbeManager()
 {
   //If the manager goes out of scope, stop the session.
   if (mIsActive && mRegistrationHandle) {
     StopSession();
   }
 }
 ProbeManager::ProbeManager(const nsCID &aApplicationUID,
                            const nsACString &aApplicationName)
   : mApplicationUID(aApplicationUID)
   , mApplicationName(aApplicationName)
   , mSessionHandle(0)
   , mRegistrationHandle(0)
 {
 #if defined(MOZ_LOGGING)
   char cidStr[NSID_LENGTH];
   aApplicationUID.ToProvidedString(cidStr);
   LOG(("ProbeManager::Init for application %s, %s",
        aApplicationName.Data(), cidStr));
 #endif
 }
 //Note: The Windows API is just a little bit scary there.
 //The only way to obtain the session handle is to
 //- ignore the session handle obtained from RegisterTraceGuids
 //- pass a callback
 //- in that callback, request the session handle through
 //      GetTraceLoggerHandle and some opaque value received by the callback
 ULONG WINAPI ControlCallback(
                              WMIDPREQUESTCODE RequestCode,
                              PVOID Context,
                              ULONG *Reserved,
                              PVOID Buffer
                              )
 {
   ProbeManager* context = (ProbeManager*)Context;
   switch(RequestCode)
   {
   case WMI_ENABLE_EVENTS:
     {
       context->mIsActive = true;
       TRACEHANDLE sessionHandle = GetTraceLoggerHandle(Buffer);
       //Note: We only accept one handle
       if ((HANDLE)sessionHandle == INVALID_HANDLE_VALUE) {
         ULONG result = GetLastError();
         LOG(("Probes: ControlCallback failed, %ul", result));
         return result;
       } else if (context->mIsActive && context->mSessionHandle
                 && context->mSessionHandle != sessionHandle) {
         LOG(("Probes: Can only handle one context at a time, "
              "ignoring activation"));
         return ERROR_SUCCESS;
       } else {
         context->mSessionHandle = sessionHandle;
         LOG(("Probes: ControlCallback activated"));
         return ERROR_SUCCESS;
       }
     }
   case WMI_DISABLE_EVENTS:
     context->mIsActive      = false;
     context->mSessionHandle = 0;
     LOG(("Probes: ControlCallback deactivated"));
     return ERROR_SUCCESS;
   default:
     LOG(("Probes: ControlCallback does not know what to do with %d",
          RequestCode));
     return ERROR_INVALID_PARAMETER;
   }
 }
 already_AddRefed<Probe> ProbeManager::GetProbe(const nsCID &eventUID,
                                const nsACString &eventName)
 {
   nsRefPtr<Probe> result(new Probe(eventUID, eventName, this));
   mAllProbes.AppendElement(result);
   return result.forget();
 }
 nsresult ProbeManager::StartSession()
 {
   return StartSession(mAllProbes);
 }
 nsresult ProbeManager::StartSession(nsTArray<nsRefPtr<Probe>> &aProbes)
 {
   const size_t probesCount = aProbes.Length();
   _TRACE_GUID_REGISTRATION* probes = new _TRACE_GUID_REGISTRATION[probesCount];
   for (unsigned int i = 0; i < probesCount; ++i) {
     const Probe *probe = aProbes[i];
     const Probe *probeX = static_cast<const Probe*>(probe);
     probes[i].Guid = (LPCGUID)&(probeX->mGUID);
   }
   ULONG result =
     RegisterTraceGuids(&ControlCallback
                      /*RequestAddress: Sets mSessions appropriately.*/,
                      this
                      /*RequestContext: Passed to ControlCallback*/,
                      (LPGUID)&mApplicationUID
                      /*ControlGuid:    Tracing GUID
                       the cast comes from MSDN examples*/,
                      probesCount
                      /*GuidCount:      Number of probes*/,
                      probes
                      /*TraceGuidReg:   Probes registration*/,
                      nullptr
                      /*MofImagePath:   Must be nullptr, says MSDN*/,
                      nullptr
                      /*MofResourceName:Must be nullptr, says MSDN*/,
                      &mRegistrationHandle
                      /*RegistrationHandle: Handler.
                       used only for unregistration*/
                      );
   delete[] probes;
   if (NS_WARN_IF(result != ERROR_SUCCESS))
     return NS_ERROR_UNEXPECTED;
   return NS_OK;
 }
 nsresult ProbeManager::StopSession()
 {
   LOG(("Probes: Stopping measures"));
   if (mSessionHandle != 0) {
     ULONG result = UnregisterTraceGuids(mSessionHandle);
     mSessionHandle = 0;
     if (result != ERROR_SUCCESS) {
       return NS_ERROR_INVALID_ARG;
     }
   }
   return NS_OK;
 }
 }
 }

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xpcom/build/perfprobe.cpp@6474c204b198 (annotated)

xpcom/build/perfprobe.cpp