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: 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/. */
/*
* JS engine garbage collector API.
*/
#ifndef gc_GC_h
#define gc_GC_h
#include "gc/GCEnum.h"
#include "js/GCAPI.h"
#include "js/HeapAPI.h"
#include "js/RealmIterators.h"
#include "js/TraceKind.h"
class JSTracer;
namespace JS {
class RealmOptions;
}
namespace js {
class Nursery;
namespace gc {
class Arena;
class TenuredChunk;
} /* namespace gc */
// Define name, key and writability for the GC parameters.
#define FOR_EACH_GC_PARAM(_) \
_("maxBytes", JSGC_MAX_BYTES, true) \
_("minNurseryBytes", JSGC_MIN_NURSERY_BYTES, true) \
_("maxNurseryBytes", JSGC_MAX_NURSERY_BYTES, true) \
_("gcBytes", JSGC_BYTES, false) \
_("nurseryBytes", JSGC_NURSERY_BYTES, false) \
_("gcNumber", JSGC_NUMBER, false) \
_("majorGCNumber", JSGC_MAJOR_GC_NUMBER, false) \
_("minorGCNumber", JSGC_MINOR_GC_NUMBER, false) \
_("incrementalGCEnabled", JSGC_INCREMENTAL_GC_ENABLED, true) \
_("perZoneGCEnabled", JSGC_PER_ZONE_GC_ENABLED, true) \
_("unusedChunks", JSGC_UNUSED_CHUNKS, false) \
_("totalChunks", JSGC_TOTAL_CHUNKS, false) \
_("sliceTimeBudgetMS", JSGC_SLICE_TIME_BUDGET_MS, true) \
_("highFrequencyTimeLimit", JSGC_HIGH_FREQUENCY_TIME_LIMIT, true) \
_("smallHeapSizeMax", JSGC_SMALL_HEAP_SIZE_MAX, true) \
_("largeHeapSizeMin", JSGC_LARGE_HEAP_SIZE_MIN, true) \
_("highFrequencySmallHeapGrowth", JSGC_HIGH_FREQUENCY_SMALL_HEAP_GROWTH, \
true) \
_("highFrequencyLargeHeapGrowth", JSGC_HIGH_FREQUENCY_LARGE_HEAP_GROWTH, \
true) \
_("lowFrequencyHeapGrowth", JSGC_LOW_FREQUENCY_HEAP_GROWTH, true) \
_("balancedHeapLimitsEnabled", JSGC_BALANCED_HEAP_LIMITS_ENABLED, true) \
_("heapGrowthFactor", JSGC_HEAP_GROWTH_FACTOR, true) \
_("allocationThreshold", JSGC_ALLOCATION_THRESHOLD, true) \
_("smallHeapIncrementalLimit", JSGC_SMALL_HEAP_INCREMENTAL_LIMIT, true) \
_("largeHeapIncrementalLimit", JSGC_LARGE_HEAP_INCREMENTAL_LIMIT, true) \
_("minEmptyChunkCount", JSGC_MIN_EMPTY_CHUNK_COUNT, true) \
_("maxEmptyChunkCount", JSGC_MAX_EMPTY_CHUNK_COUNT, true) \
_("compactingEnabled", JSGC_COMPACTING_ENABLED, true) \
_("parallelMarkingEnabled", JSGC_PARALLEL_MARKING_ENABLED, true) \
_("parallelMarkingThresholdKB", JSGC_PARALLEL_MARKING_THRESHOLD_KB, true) \
_("minLastDitchGCPeriod", JSGC_MIN_LAST_DITCH_GC_PERIOD, true) \
_("nurseryFreeThresholdForIdleCollection", \
JSGC_NURSERY_FREE_THRESHOLD_FOR_IDLE_COLLECTION, true) \
_("nurseryFreeThresholdForIdleCollectionPercent", \
JSGC_NURSERY_FREE_THRESHOLD_FOR_IDLE_COLLECTION_PERCENT, true) \
_("nurseryTimeoutForIdleCollectionMS", \
JSGC_NURSERY_TIMEOUT_FOR_IDLE_COLLECTION_MS, true) \
_("pretenureThreshold", JSGC_PRETENURE_THRESHOLD, true) \
_("zoneAllocDelayKB", JSGC_ZONE_ALLOC_DELAY_KB, true) \
_("mallocThresholdBase", JSGC_MALLOC_THRESHOLD_BASE, true) \
_("urgentThreshold", JSGC_URGENT_THRESHOLD_MB, true) \
_("chunkBytes", JSGC_CHUNK_BYTES, false) \
_("helperThreadRatio", JSGC_HELPER_THREAD_RATIO, true) \
_("maxHelperThreads", JSGC_MAX_HELPER_THREADS, true) \
_("helperThreadCount", JSGC_HELPER_THREAD_COUNT, false) \
_("markingThreadCount", JSGC_MARKING_THREAD_COUNT, true) \
_("systemPageSizeKB", JSGC_SYSTEM_PAGE_SIZE_KB, false)
// Get the key and writability give a GC parameter name.
extern bool GetGCParameterInfo(const char* name, JSGCParamKey* keyOut,
bool* writableOut);
extern void TraceRuntime(JSTracer* trc);
// Trace roots but don't evict the nursery first; used from DumpHeap.
extern void TraceRuntimeWithoutEviction(JSTracer* trc);
extern void ReleaseAllJITCode(JS::GCContext* gcx);
extern void PrepareForDebugGC(JSRuntime* rt);
/* Functions for managing cross compartment gray pointers. */
extern void NotifyGCNukeWrapper(JSContext* cx, JSObject* wrapper);
extern unsigned NotifyGCPreSwap(JSObject* a, JSObject* b);
extern void NotifyGCPostSwap(JSObject* a, JSObject* b, unsigned preResult);
using IterateChunkCallback = void (*)(JSRuntime*, void*, gc::TenuredChunk*,
const JS::AutoRequireNoGC&);
using IterateZoneCallback = void (*)(JSRuntime*, void*, JS::Zone*,
const JS::AutoRequireNoGC&);
using IterateArenaCallback = void (*)(JSRuntime*, void*, gc::Arena*,
JS::TraceKind, size_t,
const JS::AutoRequireNoGC&);
using IterateCellCallback = void (*)(JSRuntime*, void*, JS::GCCellPtr, size_t,
const JS::AutoRequireNoGC&);
/*
* This function calls |zoneCallback| on every zone, |realmCallback| on
* every realm, |arenaCallback| on every in-use arena, and |cellCallback|
* on every in-use cell in the GC heap.
*
* Note that no read barrier is triggered on the cells passed to cellCallback,
* so no these pointers must not escape the callback.
*/
extern void IterateHeapUnbarriered(JSContext* cx, void* data,
IterateZoneCallback zoneCallback,
JS::IterateRealmCallback realmCallback,
IterateArenaCallback arenaCallback,
IterateCellCallback cellCallback);
/*
* This function is like IterateHeapUnbarriered, but does it for a single zone.
*/
extern void IterateHeapUnbarrieredForZone(
JSContext* cx, JS::Zone* zone, void* data, IterateZoneCallback zoneCallback,
JS::IterateRealmCallback realmCallback, IterateArenaCallback arenaCallback,
IterateCellCallback cellCallback);
/*
* Invoke chunkCallback on every in-use chunk.
*/
extern void IterateChunks(JSContext* cx, void* data,
IterateChunkCallback chunkCallback);
using IterateScriptCallback = void (*)(JSRuntime*, void*, BaseScript*,
const JS::AutoRequireNoGC&);
/*
* Invoke scriptCallback on every in-use script for the given realm or for all
* realms if it is null. The scripts may or may not have bytecode.
*/
extern void IterateScripts(JSContext* cx, JS::Realm* realm, void* data,
IterateScriptCallback scriptCallback);
JS::Realm* NewRealm(JSContext* cx, JSPrincipals* principals,
const JS::RealmOptions& options);
namespace gc {
void FinishGC(JSContext* cx, JS::GCReason = JS::GCReason::FINISH_GC);
void WaitForBackgroundTasks(JSContext* cx);
enum VerifierType { PreBarrierVerifier };
#ifdef JS_GC_ZEAL
extern const char ZealModeHelpText[];
/* Check that write barriers have been used correctly. See gc/Verifier.cpp. */
void VerifyBarriers(JSRuntime* rt, VerifierType type);
void MaybeVerifyBarriers(JSContext* cx, bool always = false);
void DumpArenaInfo();
#else
static inline void VerifyBarriers(JSRuntime* rt, VerifierType type) {}
static inline void MaybeVerifyBarriers(JSContext* cx, bool always = false) {}
#endif
/*
* Instances of this class prevent GC from happening while they are live. If an
* allocation causes a heap threshold to be exceeded, no GC will be performed
* and the allocation will succeed. Allocation may still fail for other reasons.
*
* Use of this class is highly discouraged, since without GC system memory can
* become exhausted and this can cause crashes at places where we can't handle
* allocation failure.
*
* Use of this is permissible in situations where it would be impossible (or at
* least very difficult) to tolerate GC and where only a fixed number of objects
* are allocated, such as:
*
* - error reporting
* - JIT bailout handling
* - brain transplants (JSObject::swap)
* - debugging utilities not exposed to the browser
*
* This works by updating the |JSContext::suppressGC| counter which is checked
* at the start of GC.
*/
class MOZ_RAII JS_HAZ_GC_SUPPRESSED AutoSuppressGC
: public JS::AutoRequireNoGC {
int32_t& suppressGC_;
public:
explicit AutoSuppressGC(JSContext* cx);
~AutoSuppressGC() { suppressGC_--; }
};
const char* StateName(State state);
} /* namespace gc */
/* Use this to avoid assertions when manipulating the wrapper map. */
class MOZ_RAII AutoDisableProxyCheck {
public:
#ifdef DEBUG
AutoDisableProxyCheck();
~AutoDisableProxyCheck();
#else
AutoDisableProxyCheck() {}
#endif
};
struct MOZ_RAII AutoDisableCompactingGC {
explicit AutoDisableCompactingGC(JSContext* cx);
~AutoDisableCompactingGC();
private:
JSContext* cx;
};
} /* namespace js */
#endif /* gc_GC_h */
|
