summaryrefslogtreecommitdiffstats
path: root/xpcom/build/perfprobe.cpp
blob: d5a82be59d4fe8e0f506aff0269a5a3f48b0ee04 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
/* -*- 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/. */

/*****************************
 Windows implementation of probes, using xperf
 *****************************/
#include <windows.h>
#include <wmistr.h>
#include <evntrace.h>

#include "perfprobe.h"

namespace mozilla {
namespace probes {

#if defined(MOZ_LOGGING)
static LazyLogModule sProbeLog("SysProbe");
#  define LOG(x) MOZ_LOG(sProbeLog, mozilla::LogLevel::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)
    : mIsActive(false),
      mApplicationUID(aApplicationUID),
      mApplicationName(aApplicationName),
      mSessionHandle(0),
      mRegistrationHandle(0),
      mInitialized(false) {
#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 aRequestCode, PVOID aContext,
                             ULONG* aReserved, PVOID aBuffer) {
  ProbeManager* context = (ProbeManager*)aContext;
  switch (aRequestCode) {
    case WMI_ENABLE_EVENTS: {
      context->mIsActive = true;
      TRACEHANDLE sessionHandle = GetTraceLoggerHandle(aBuffer);
      // Note: We only accept one handle
      if ((HANDLE)sessionHandle == INVALID_HANDLE_VALUE) {
        ULONG result = GetLastError();
        LOG(("Probes: ControlCallback failed, %lu", 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",
           aRequestCode));
      return ERROR_INVALID_PARAMETER;
  }
}

already_AddRefed<Probe> ProbeManager::GetProbe(const nsCID& aEventUID,
                                               const nsACString& aEventName) {
  RefPtr<Probe> result(new Probe(aEventUID, aEventName, this));
  mAllProbes.AppendElement(result);
  return result.forget();
}

nsresult ProbeManager::StartSession() { return StartSession(mAllProbes); }

nsresult ProbeManager::StartSession(nsTArray<RefPtr<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;
}

}  // namespace probes
}  // namespace mozilla