JDK14/Java14源码在线阅读
/*
* Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#ifndef SHARE_MEMORY_ALLOCATION_HPP
#define SHARE_MEMORY_ALLOCATION_HPP
#include "utilities/globalDefinitions.hpp"
#include "utilities/macros.hpp"
#include <new>
class outputStream;
class Thread;
class AllocFailStrategy {
public:
enum AllocFailEnum { EXIT_OOM, RETURN_NULL };
};
typedef AllocFailStrategy::AllocFailEnum AllocFailType;
// The virtual machine must never call one of the implicitly declared
// global allocation or deletion functions. (Such calls may result in
// link-time or run-time errors.) For convenience and documentation of
// intended use, classes in the virtual machine may be derived from one
// of the following allocation classes, some of which define allocation
// and deletion functions.
// Note: std::malloc and std::free should never called directly.
//
// For objects allocated in the resource area (see resourceArea.hpp).
// - ResourceObj
//
// For objects allocated in the C-heap (managed by: free & malloc and tracked with NMT)
// - CHeapObj
//
// For objects allocated on the stack.
// - StackObj
//
// For classes used as name spaces.
// - AllStatic
//
// For classes in Metaspace (class data)
// - MetaspaceObj
//
// The printable subclasses are used for debugging and define virtual
// member functions for printing. Classes that avoid allocating the
// vtbl entries in the objects should therefore not be the printable
// subclasses.
//
// The following macros and function should be used to allocate memory
// directly in the resource area or in the C-heap, The _OBJ variants
// of the NEW/FREE_C_HEAP macros are used for alloc/dealloc simple
// objects which are not inherited from CHeapObj, note constructor and
// destructor are not called. The preferable way to allocate objects
// is using the new operator.
//
// WARNING: The array variant must only be used for a homogenous array
// where all objects are of the exact type specified. If subtypes are
// stored in the array then must pay attention to calling destructors
// at needed.
//
// NEW_RESOURCE_ARRAY*
// REALLOC_RESOURCE_ARRAY*
// FREE_RESOURCE_ARRAY*
// NEW_RESOURCE_OBJ*
// NEW_C_HEAP_ARRAY*
// REALLOC_C_HEAP_ARRAY*
// FREE_C_HEAP_ARRAY*
// NEW_C_HEAP_OBJ*
// FREE_C_HEAP_OBJ
//
// char* AllocateHeap(size_t size, MEMFLAGS flags, const NativeCallStack& stack, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
// char* AllocateHeap(size_t size, MEMFLAGS flags, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
// char* ReallocateHeap(char *old, size_t size, MEMFLAGS flag, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
// void FreeHeap(void* p);
//
// In non product mode we introduce a super class for all allocation classes
// that supports printing.
// We avoid the superclass in product mode to save space.
#ifdef PRODUCT
#define ALLOCATION_SUPER_CLASS_SPEC
#else
#define ALLOCATION_SUPER_CLASS_SPEC : public AllocatedObj
class AllocatedObj {
public:
// Printing support
void print() const;
void print_value() const;
virtual void print_on(outputStream* st) const;
virtual void print_value_on(outputStream* st) const;
};
#endif
#define MEMORY_TYPES_DO(f) \
/* Memory type by sub systems. It occupies lower byte. */ \
f(mtJavaHeap, "Java Heap") /* Java heap */ \
f(mtClass, "Class") /* Java classes */ \
f(mtThread, "Thread") /* thread objects */ \
f(mtThreadStack, "Thread Stack") \
f(mtCode, "Code") /* generated code */ \
f(mtGC, "GC") \
f(mtCompiler, "Compiler") \
f(mtJVMCI, "JVMCI") \
f(mtInternal, "Internal") /* memory used by VM, but does not belong to */ \
/* any of above categories, and not used by */ \
/* NMT */ \
f(mtOther, "Other") /* memory not used by VM */ \
f(mtSymbol, "Symbol") \
f(mtNMT, "Native Memory Tracking") /* memory used by NMT */ \
f(mtClassShared, "Shared class space") /* class data sharing */ \
f(mtChunk, "Arena Chunk") /* chunk that holds content of arenas */ \
f(mtTest, "Test") /* Test type for verifying NMT */ \
f(mtTracing, "Tracing") \
f(mtLogging, "Logging") \
f(mtStatistics, "Statistics") \
f(mtArguments, "Arguments") \
f(mtModule, "Module") \
f(mtSafepoint, "Safepoint") \
f(mtSynchronizer, "Synchronization") \
f(mtNone, "Unknown") \
//end
#define MEMORY_TYPE_DECLARE_ENUM(type, human_readable) \
type,
/*
* Memory types
*/
enum MemoryType {
MEMORY_TYPES_DO(MEMORY_TYPE_DECLARE_ENUM)
mt_number_of_types // number of memory types (mtDontTrack
// is not included as validate type)
};
typedef MemoryType MEMFLAGS;
#if INCLUDE_NMT
extern bool NMT_track_callsite;
#else
const bool NMT_track_callsite = false;
#endif // INCLUDE_NMT
class NativeCallStack;
char* AllocateHeap(size_t size,
MEMFLAGS flags,
const NativeCallStack& stack,
AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
char* AllocateHeap(size_t size,
MEMFLAGS flags,
AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
char* ReallocateHeap(char *old,
size_t size,
MEMFLAGS flag,
AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
// handles NULL pointers
void FreeHeap(void* p);
template <MEMFLAGS F> class CHeapObj ALLOCATION_SUPER_CLASS_SPEC {
public:
ALWAYSINLINE void* operator new(size_t size) throw() {
return (void*)AllocateHeap(size, F);
}
ALWAYSINLINE void* operator new(size_t size,
const NativeCallStack& stack) throw() {
return (void*)AllocateHeap(size, F, stack);
}
ALWAYSINLINE void* operator new(size_t size, const std::nothrow_t&,
const NativeCallStack& stack) throw() {
return (void*)AllocateHeap(size, F, stack, AllocFailStrategy::RETURN_NULL);
}
ALWAYSINLINE void* operator new(size_t size, const std::nothrow_t&) throw() {
return (void*)AllocateHeap(size, F, AllocFailStrategy::RETURN_NULL);
}
ALWAYSINLINE void* operator new[](size_t size) throw() {
return (void*)AllocateHeap(size, F);
}
ALWAYSINLINE void* operator new[](size_t size,
const NativeCallStack& stack) throw() {
return (void*)AllocateHeap(size, F, stack);
}
ALWAYSINLINE void* operator new[](size_t size, const std::nothrow_t&,
const NativeCallStack& stack) throw() {
return (void*)AllocateHeap(size, F, stack, AllocFailStrategy::RETURN_NULL);
}
ALWAYSINLINE void* operator new[](size_t size, const std::nothrow_t&) throw() {
return (void*)AllocateHeap(size, F, AllocFailStrategy::RETURN_NULL);
}
void operator delete(void* p) { FreeHeap(p); }
void operator delete [] (void* p) { FreeHeap(p); }
};
// Base class for objects allocated on the stack only.
// Calling new or delete will result in fatal error.
class StackObj ALLOCATION_SUPER_CLASS_SPEC {
private:
void* operator new(size_t size) throw();
void* operator new [](size_t size) throw();
void operator delete(void* p);
void operator delete [](void* p);
};
// Base class for objects stored in Metaspace.
// Calling delete will result in fatal error.
//
// Do not inherit from something with a vptr because this class does
// not introduce one. This class is used to allocate both shared read-only
// and shared read-write classes.
//
class ClassLoaderData;
class MetaspaceClosure;
class MetaspaceObj {
friend class VMStructs;
// When CDS is enabled, all shared metaspace objects are mapped
// into a single contiguous memory block, so we can use these
// two pointers to quickly determine if something is in the
// shared metaspace.
// When CDS is not enabled, both pointers are set to NULL.
static void* _shared_metaspace_base; // (inclusive) low address
static void* _shared_metaspace_top; // (exclusive) high address
public:
// Returns true if the pointer points to a valid MetaspaceObj. A valid
// MetaspaceObj is MetaWord-aligned and contained within either
// non-shared or shared metaspace.
static bool is_valid(const MetaspaceObj* p);
static bool is_shared(const MetaspaceObj* p) {
// If no shared metaspace regions are mapped, _shared_metaspace_{base,top} will
// both be NULL and all values of p will be rejected quickly.
return (((void*)p) < _shared_metaspace_top &&
((void*)p) >= _shared_metaspace_base);
}
bool is_shared() const { return MetaspaceObj::is_shared(this); }
void print_address_on(outputStream* st) const; // nonvirtual address printing
static void set_shared_metaspace_range(void* base, void* top) {
_shared_metaspace_base = base;
_shared_metaspace_top = top;
}
static void* shared_metaspace_base() { return _shared_metaspace_base; }
static void* shared_metaspace_top() { return _shared_metaspace_top; }
#define METASPACE_OBJ_TYPES_DO(f) \
f(Class) \
f(Symbol) \
f(TypeArrayU1) \
f(TypeArrayU2) \
f(TypeArrayU4) \
f(TypeArrayU8) \
f(TypeArrayOther) \
f(Method) \
f(ConstMethod) \
f(MethodData) \
f(ConstantPool) \
f(ConstantPoolCache) \
f(Annotations) \
f(MethodCounters) \
f(RecordComponent)
#define METASPACE_OBJ_TYPE_DECLARE(name) name ## Type,
#define METASPACE_OBJ_TYPE_NAME_CASE(name) case name ## Type: return #name;
enum Type {
// Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
METASPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
_number_of_types
};
static const char * type_name(Type type) {
switch(type) {
METASPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
default:
ShouldNotReachHere();
return NULL;
}
}
static MetaspaceObj::Type array_type(size_t elem_size) {
switch (elem_size) {
case 1: return TypeArrayU1Type;
case 2: return TypeArrayU2Type;
case 4: return TypeArrayU4Type;
case 8: return TypeArrayU8Type;
default:
return TypeArrayOtherType;
}
}
void* operator new(size_t size, ClassLoaderData* loader_data,
size_t word_size,
Type type, Thread* thread) throw();
// can't use TRAPS from this header file.
void operator delete(void* p) { ShouldNotCallThis(); }
// Declare a *static* method with the same signature in any subclass of MetaspaceObj
// that should be read-only by default. See symbol.hpp for an example. This function
// is used by the templates in metaspaceClosure.hpp
static bool is_read_only_by_default() { return false; }
};
// Base class for classes that constitute name spaces.
class Arena;
class AllStatic {
public:
AllStatic() { ShouldNotCallThis(); }
~AllStatic() { ShouldNotCallThis(); }
};
extern char* resource_allocate_bytes(size_t size,
AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
extern char* resource_allocate_bytes(Thread* thread, size_t size,
AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
extern char* resource_reallocate_bytes( char *old, size_t old_size, size_t new_size,
AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
extern void resource_free_bytes( char *old, size_t size );
//----------------------------------------------------------------------
// Base class for objects allocated in the resource area per default.
// Optionally, objects may be allocated on the C heap with
// new(ResourceObj::C_HEAP) Foo(...) or in an Arena with new (&arena)
// ResourceObj's can be allocated within other objects, but don't use
// new or delete (allocation_type is unknown). If new is used to allocate,
// use delete to deallocate.
class ResourceObj ALLOCATION_SUPER_CLASS_SPEC {
public:
enum allocation_type { STACK_OR_EMBEDDED = 0, RESOURCE_AREA, C_HEAP, ARENA, allocation_mask = 0x3 };
static void set_allocation_type(address res, allocation_type type) NOT_DEBUG_RETURN;
#ifdef ASSERT
private:
// When this object is allocated on stack the new() operator is not
// called but garbage on stack may look like a valid allocation_type.
// Store negated 'this' pointer when new() is called to distinguish cases.
// Use second array's element for verification value to distinguish garbage.
uintptr_t _allocation_t[2];
bool is_type_set() const;
void initialize_allocation_info();
public:
allocation_type get_allocation_type() const;
bool allocated_on_stack() const { return get_allocation_type() == STACK_OR_EMBEDDED; }
bool allocated_on_res_area() const { return get_allocation_type() == RESOURCE_AREA; }
bool allocated_on_C_heap() const { return get_allocation_type() == C_HEAP; }
bool allocated_on_arena() const { return get_allocation_type() == ARENA; }
protected:
ResourceObj(); // default constructor
ResourceObj(const ResourceObj& r); // default copy constructor
ResourceObj& operator=(const ResourceObj& r); // default copy assignment
~ResourceObj();
#endif // ASSERT
public:
void* operator new(size_t size, allocation_type type, MEMFLAGS flags) throw();
void* operator new [](size_t size, allocation_type type, MEMFLAGS flags) throw();
void* operator new(size_t size, const std::nothrow_t& nothrow_constant,
allocation_type type, MEMFLAGS flags) throw();
void* operator new [](size_t size, const std::nothrow_t& nothrow_constant,
allocation_type type, MEMFLAGS flags) throw();
void* operator new(size_t size, Arena *arena) throw();
void* operator new [](size_t size, Arena *arena) throw();
void* operator new(size_t size) throw() {
address res = (address)resource_allocate_bytes(size);
DEBUG_ONLY(set_allocation_type(res, RESOURCE_AREA);)
return res;
}
void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
address res = (address)resource_allocate_bytes(size, AllocFailStrategy::RETURN_NULL);
DEBUG_ONLY(if (res != NULL) set_allocation_type(res, RESOURCE_AREA);)
return res;
}
void* operator new [](size_t size) throw() {
address res = (address)resource_allocate_bytes(size);
DEBUG_ONLY(set_allocation_type(res, RESOURCE_AREA);)
return res;
}
void* operator new [](size_t size, const std::nothrow_t& nothrow_constant) throw() {
address res = (address)resource_allocate_bytes(size, AllocFailStrategy::RETURN_NULL);
DEBUG_ONLY(if (res != NULL) set_allocation_type(res, RESOURCE_AREA);)
return res;
}
void operator delete(void* p);
void operator delete [](void* p);
};
// One of the following macros must be used when allocating an array
// or object to determine whether it should reside in the C heap on in
// the resource area.
#define NEW_RESOURCE_ARRAY(type, size)\
(type*) resource_allocate_bytes((size) * sizeof(type))
#define NEW_RESOURCE_ARRAY_RETURN_NULL(type, size)\
(type*) resource_allocate_bytes((size) * sizeof(type), AllocFailStrategy::RETURN_NULL)
#define NEW_RESOURCE_ARRAY_IN_THREAD(thread, type, size)\
(type*) resource_allocate_bytes(thread, (size) * sizeof(type))
#define NEW_RESOURCE_ARRAY_IN_THREAD_RETURN_NULL(thread, type, size)\
(type*) resource_allocate_bytes(thread, (size) * sizeof(type), AllocFailStrategy::RETURN_NULL)
#define REALLOC_RESOURCE_ARRAY(type, old, old_size, new_size)\
(type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type), (new_size) * sizeof(type))
#define REALLOC_RESOURCE_ARRAY_RETURN_NULL(type, old, old_size, new_size)\
(type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type),\
(new_size) * sizeof(type), AllocFailStrategy::RETURN_NULL)
#define FREE_RESOURCE_ARRAY(type, old, size)\
resource_free_bytes((char*)(old), (size) * sizeof(type))
#define FREE_FAST(old)\
/* nop */
#define NEW_RESOURCE_OBJ(type)\
NEW_RESOURCE_ARRAY(type, 1)
#define NEW_RESOURCE_OBJ_RETURN_NULL(type)\
NEW_RESOURCE_ARRAY_RETURN_NULL(type, 1)
#define NEW_C_HEAP_ARRAY3(type, size, memflags, pc, allocfail)\
(type*) AllocateHeap((size) * sizeof(type), memflags, pc, allocfail)
#define NEW_C_HEAP_ARRAY2(type, size, memflags, pc)\
(type*) (AllocateHeap((size) * sizeof(type), memflags, pc))
#define NEW_C_HEAP_ARRAY(type, size, memflags)\
(type*) (AllocateHeap((size) * sizeof(type), memflags))
#define NEW_C_HEAP_ARRAY2_RETURN_NULL(type, size, memflags, pc)\
NEW_C_HEAP_ARRAY3(type, (size), memflags, pc, AllocFailStrategy::RETURN_NULL)
#define NEW_C_HEAP_ARRAY_RETURN_NULL(type, size, memflags)\
NEW_C_HEAP_ARRAY3(type, (size), memflags, CURRENT_PC, AllocFailStrategy::RETURN_NULL)
#define REALLOC_C_HEAP_ARRAY(type, old, size, memflags)\
(type*) (ReallocateHeap((char*)(old), (size) * sizeof(type), memflags))
#define REALLOC_C_HEAP_ARRAY_RETURN_NULL(type, old, size, memflags)\
(type*) (ReallocateHeap((char*)(old), (size) * sizeof(type), memflags, AllocFailStrategy::RETURN_NULL))
#define FREE_C_HEAP_ARRAY(type, old) \
FreeHeap((char*)(old))
// allocate type in heap without calling ctor
#define NEW_C_HEAP_OBJ(type, memflags)\
NEW_C_HEAP_ARRAY(type, 1, memflags)
#define NEW_C_HEAP_OBJ_RETURN_NULL(type, memflags)\
NEW_C_HEAP_ARRAY_RETURN_NULL(type, 1, memflags)
// deallocate obj of type in heap without calling dtor
#define FREE_C_HEAP_OBJ(objname)\
FreeHeap((char*)objname);
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