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
216
217
218
219
220
221
222
223
224
225
|
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/debug/profiler.h"
#include <string>
#include "base/debug/debugging_flags.h"
#include "base/process/process_handle.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_util.h"
#include "build/build_config.h"
#if defined(OS_WIN)
#include "base/win/current_module.h"
#include "base/win/pe_image.h"
#endif // defined(OS_WIN)
// TODO(peria): Enable profiling on Windows.
#if BUILDFLAG(ENABLE_PROFILING) && !defined(NO_TCMALLOC) && !defined(OS_WIN)
#include "third_party/tcmalloc/chromium/src/gperftools/profiler.h"
#endif
namespace base {
namespace debug {
// TODO(peria): Enable profiling on Windows.
#if BUILDFLAG(ENABLE_PROFILING) && !defined(NO_TCMALLOC) && !defined(OS_WIN)
static int profile_count = 0;
void StartProfiling(const std::string& name) {
++profile_count;
std::string full_name(name);
std::string pid = IntToString(GetCurrentProcId());
std::string count = IntToString(profile_count);
ReplaceSubstringsAfterOffset(&full_name, 0, "{pid}", pid);
ReplaceSubstringsAfterOffset(&full_name, 0, "{count}", count);
ProfilerStart(full_name.c_str());
}
void StopProfiling() {
ProfilerFlush();
ProfilerStop();
}
void FlushProfiling() {
ProfilerFlush();
}
bool BeingProfiled() {
return ProfilingIsEnabledForAllThreads();
}
void RestartProfilingAfterFork() {
ProfilerRegisterThread();
}
bool IsProfilingSupported() {
return true;
}
#else
void StartProfiling(const std::string& name) {
}
void StopProfiling() {
}
void FlushProfiling() {
}
bool BeingProfiled() {
return false;
}
void RestartProfilingAfterFork() {
}
bool IsProfilingSupported() {
return false;
}
#endif
#if !defined(OS_WIN)
bool IsBinaryInstrumented() {
return false;
}
ReturnAddressLocationResolver GetProfilerReturnAddrResolutionFunc() {
return NULL;
}
DynamicFunctionEntryHook GetProfilerDynamicFunctionEntryHookFunc() {
return NULL;
}
AddDynamicSymbol GetProfilerAddDynamicSymbolFunc() {
return NULL;
}
MoveDynamicSymbol GetProfilerMoveDynamicSymbolFunc() {
return NULL;
}
#else // defined(OS_WIN)
bool IsBinaryInstrumented() {
enum InstrumentationCheckState {
UNINITIALIZED,
INSTRUMENTED_IMAGE,
NON_INSTRUMENTED_IMAGE,
};
static InstrumentationCheckState state = UNINITIALIZED;
if (state == UNINITIALIZED) {
base::win::PEImage image(CURRENT_MODULE());
// Check to be sure our image is structured as we'd expect.
DCHECK(image.VerifyMagic());
// Syzygy-instrumented binaries contain a PE image section named ".thunks",
// and all Syzygy-modified binaries contain the ".syzygy" image section.
// This is a very fast check, as it only looks at the image header.
if ((image.GetImageSectionHeaderByName(".thunks") != NULL) &&
(image.GetImageSectionHeaderByName(".syzygy") != NULL)) {
state = INSTRUMENTED_IMAGE;
} else {
state = NON_INSTRUMENTED_IMAGE;
}
}
DCHECK(state != UNINITIALIZED);
return state == INSTRUMENTED_IMAGE;
}
namespace {
struct FunctionSearchContext {
const char* name;
FARPROC function;
};
// Callback function to PEImage::EnumImportChunks.
bool FindResolutionFunctionInImports(
const base::win::PEImage &image, const char* module_name,
PIMAGE_THUNK_DATA unused_name_table, PIMAGE_THUNK_DATA import_address_table,
PVOID cookie) {
FunctionSearchContext* context =
reinterpret_cast<FunctionSearchContext*>(cookie);
DCHECK(context);
DCHECK(!context->function);
// Our import address table contains pointers to the functions we import
// at this point. Let's retrieve the first such function and use it to
// find the module this import was resolved to by the loader.
const wchar_t* function_in_module =
reinterpret_cast<const wchar_t*>(import_address_table->u1.Function);
// Retrieve the module by a function in the module.
const DWORD kFlags = GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |
GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT;
HMODULE module = NULL;
if (!::GetModuleHandleEx(kFlags, function_in_module, &module)) {
// This can happen if someone IAT patches us to a thunk.
return true;
}
// See whether this module exports the function we're looking for.
FARPROC exported_func = ::GetProcAddress(module, context->name);
if (exported_func != NULL) {
// We found it, return the function and terminate the enumeration.
context->function = exported_func;
return false;
}
// Keep going.
return true;
}
template <typename FunctionType>
FunctionType FindFunctionInImports(const char* function_name) {
if (!IsBinaryInstrumented())
return NULL;
base::win::PEImage image(CURRENT_MODULE());
FunctionSearchContext ctx = { function_name, NULL };
image.EnumImportChunks(FindResolutionFunctionInImports, &ctx);
return reinterpret_cast<FunctionType>(ctx.function);
}
} // namespace
ReturnAddressLocationResolver GetProfilerReturnAddrResolutionFunc() {
return FindFunctionInImports<ReturnAddressLocationResolver>(
"ResolveReturnAddressLocation");
}
DynamicFunctionEntryHook GetProfilerDynamicFunctionEntryHookFunc() {
return FindFunctionInImports<DynamicFunctionEntryHook>(
"OnDynamicFunctionEntry");
}
AddDynamicSymbol GetProfilerAddDynamicSymbolFunc() {
return FindFunctionInImports<AddDynamicSymbol>(
"AddDynamicSymbol");
}
MoveDynamicSymbol GetProfilerMoveDynamicSymbolFunc() {
return FindFunctionInImports<MoveDynamicSymbol>(
"MoveDynamicSymbol");
}
#endif // defined(OS_WIN)
} // namespace debug
} // namespace base
|
