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
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sts=4 et sw=4 tw=99:
* 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/. */
#ifdef JS_GC_TRACE
#include "gc/GCTrace.h"
#include <stdio.h>
#include <string.h>
#include "gc/GCTraceFormat.h"
#include "js/HashTable.h"
using namespace js;
using namespace js::gc;
JS_STATIC_ASSERT(AllocKinds == unsigned(AllocKind::LIMIT));
JS_STATIC_ASSERT(LastObjectAllocKind == unsigned(AllocKind::OBJECT_LAST));
static FILE* gcTraceFile = nullptr;
static HashSet<const Class*, DefaultHasher<const Class*>, SystemAllocPolicy> tracedClasses;
static HashSet<const ObjectGroup*, DefaultHasher<const ObjectGroup*>, SystemAllocPolicy> tracedGroups;
static inline void
WriteWord(uint64_t data)
{
if (gcTraceFile)
fwrite(&data, sizeof(data), 1, gcTraceFile);
}
static inline void
TraceEvent(GCTraceEvent event, uint64_t payload = 0, uint8_t extra = 0)
{
MOZ_ASSERT(event < GCTraceEventCount);
MOZ_ASSERT((payload >> TracePayloadBits) == 0);
WriteWord((uint64_t(event) << TraceEventShift) |
(uint64_t(extra) << TraceExtraShift) | payload);
}
static inline void
TraceAddress(const void* p)
{
TraceEvent(TraceDataAddress, uint64_t(p));
}
static inline void
TraceInt(uint32_t data)
{
TraceEvent(TraceDataInt, data);
}
static void
TraceString(const char* string)
{
JS_STATIC_ASSERT(sizeof(char) == 1);
size_t length = strlen(string);
const unsigned charsPerWord = sizeof(uint64_t);
unsigned wordCount = (length + charsPerWord - 1) / charsPerWord;
TraceEvent(TraceDataString, length);
for (unsigned i = 0; i < wordCount; ++i) {
union
{
uint64_t word;
char chars[charsPerWord];
} data;
strncpy(data.chars, string + (i * charsPerWord), charsPerWord);
WriteWord(data.word);
}
}
bool
js::gc::InitTrace(GCRuntime& gc)
{
/* This currently does not support multiple runtimes. */
MOZ_ALWAYS_TRUE(!gcTraceFile);
char* filename = getenv("JS_GC_TRACE");
if (!filename)
return true;
if (!tracedClasses.init() || !tracedTypes.init()) {
FinishTrace();
return false;
}
gcTraceFile = fopen(filename, "w");
if (!gcTraceFile) {
FinishTrace();
return false;
}
TraceEvent(TraceEventInit, 0, TraceFormatVersion);
/* Trace information about thing sizes. */
for (auto kind : AllAllocKinds())
TraceEvent(TraceEventThingSize, Arena::thingSize(kind));
return true;
}
void
js::gc::FinishTrace()
{
if (gcTraceFile) {
fclose(gcTraceFile);
gcTraceFile = nullptr;
}
tracedClasses.finish();
tracedTypes.finish();
}
bool
js::gc::TraceEnabled()
{
return gcTraceFile != nullptr;
}
void
js::gc::TraceNurseryAlloc(Cell* thing, size_t size)
{
if (thing) {
/* We don't have AllocKind here, but we can work it out from size. */
unsigned slots = (size - sizeof(JSObject)) / sizeof(JS::Value);
AllocKind kind = GetBackgroundAllocKind(GetGCObjectKind(slots));
TraceEvent(TraceEventNurseryAlloc, uint64_t(thing), kind);
}
}
void
js::gc::TraceTenuredAlloc(Cell* thing, AllocKind kind)
{
if (thing)
TraceEvent(TraceEventTenuredAlloc, uint64_t(thing), kind);
}
static void
MaybeTraceClass(const Class* clasp)
{
if (tracedClasses.has(clasp))
return;
TraceEvent(TraceEventClassInfo, uint64_t(clasp));
TraceString(clasp->name);
TraceInt(clasp->flags);
TraceInt(clasp->finalize != nullptr);
MOZ_ALWAYS_TRUE(tracedClasses.put(clasp));
}
static void
MaybeTraceGroup(ObjectGroup* group)
{
if (tracedGroups.has(group))
return;
MaybeTraceClass(group->clasp());
TraceEvent(TraceEventGroupInfo, uint64_t(group));
TraceAddress(group->clasp());
TraceInt(group->flags());
MOZ_ALWAYS_TRUE(tracedGroups.put(group));
}
void
js::gc::TraceTypeNewScript(ObjectGroup* group)
{
const size_t bufLength = 128;
static char buffer[bufLength];
MOZ_ASSERT(group->hasNewScript());
JSAtom* funName = group->newScript()->fun->displayAtom();
if (!funName)
return;
size_t length = funName->length();
MOZ_ALWAYS_TRUE(length < bufLength);
CopyChars(reinterpret_cast<Latin1Char*>(buffer), *funName);
buffer[length] = 0;
TraceEvent(TraceEventTypeNewScript, uint64_t(group));
TraceString(buffer);
}
void
js::gc::TraceCreateObject(JSObject* object)
{
if (!gcTraceFile)
return;
ObjectGroup* group = object->group();
MaybeTraceGroup(group);
TraceEvent(TraceEventCreateObject, uint64_t(object));
TraceAddress(group);
}
void
js::gc::TraceMinorGCStart()
{
TraceEvent(TraceEventMinorGCStart);
}
void
js::gc::TracePromoteToTenured(Cell* src, Cell* dst)
{
TraceEvent(TraceEventPromoteToTenured, uint64_t(src));
TraceAddress(dst);
}
void
js::gc::TraceMinorGCEnd()
{
TraceEvent(TraceEventMinorGCEnd);
}
void
js::gc::TraceMajorGCStart()
{
TraceEvent(TraceEventMajorGCStart);
}
void
js::gc::TraceTenuredFinalize(Cell* thing)
{
if (!gcTraceFile)
return;
if (thing->tenuredGetAllocKind() == AllocKind::OBJECT_GROUP)
tracedGroups.remove(static_cast<const ObjectGroup*>(thing));
TraceEvent(TraceEventTenuredFinalize, uint64_t(thing));
}
void
js::gc::TraceMajorGCEnd()
{
TraceEvent(TraceEventMajorGCEnd);
}
#endif
|
