|
/*
* Copyright (c) 2019, 2022, 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_CDS_ARCHIVEUTILS_HPP
#define SHARE_CDS_ARCHIVEUTILS_HPP
#include "logging/log.hpp"
#include "memory/iterator.hpp"
#include "memory/virtualspace.hpp"
#include "utilities/bitMap.hpp"
#include "utilities/exceptions.hpp"
#include "utilities/macros.hpp"
class BootstrapInfo;
class ReservedSpace;
class VirtualSpace;
// ArchivePtrMarker is used to mark the location of pointers embedded in a CDS archive. E.g., when an
// InstanceKlass k is dumped, we mark the location of the k->_name pointer by effectively calling
// mark_pointer(/*ptr_loc=*/&k->_name). It's required that (_prt_base <= ptr_loc < _ptr_end). _ptr_base is
// fixed, but _ptr_end can be expanded as more objects are dumped.
class ArchivePtrMarker : AllStatic {
static CHeapBitMap* _ptrmap;
static VirtualSpace* _vs;
// Once _ptrmap is compacted, we don't allow bit marking anymore. This is to
// avoid unintentional copy operations after the bitmap has been finalized and written.
static bool _compacted;
static address* ptr_base() { return (address*)_vs->low(); } // committed lower bound (inclusive)
static address* ptr_end() { return (address*)_vs->high(); } // committed upper bound (exclusive)
public:
static void initialize(CHeapBitMap* ptrmap, VirtualSpace* vs);
static void mark_pointer(address* ptr_loc);
static void clear_pointer(address* ptr_loc);
static void compact(address relocatable_base, address relocatable_end);
static void compact(size_t max_non_null_offset);
template <typename T>
static void mark_pointer(T* ptr_loc) {
mark_pointer((address*)ptr_loc);
}
template <typename T>
static void set_and_mark_pointer(T* ptr_loc, T ptr_value) {
*ptr_loc = ptr_value;
mark_pointer(ptr_loc);
}
static CHeapBitMap* ptrmap() {
return _ptrmap;
}
static void reset_map_and_vs() {
_ptrmap = nullptr;
_vs = nullptr;
}
};
// SharedDataRelocator is used to shift pointers in the CDS archive.
//
// The CDS archive is basically a contiguous block of memory (divided into several regions)
// that contains multiple objects. The objects may contain direct pointers that point to other objects
// within the archive (e.g., InstanceKlass::_name points to a Symbol in the archive). During dumping, we
// built a bitmap that marks the locations of all these pointers (using ArchivePtrMarker, see comments above).
//
// The contents of the archive assumes that it’s mapped at the default SharedBaseAddress (e.g. 0x800000000).
// If the archive ends up being mapped at a different address (e.g. 0x810000000), SharedDataRelocator
// is used to shift each marked pointer by a delta (0x10000000 in this example), so that it points to
// the actually mapped location of the target object.
class SharedDataRelocator: public BitMapClosure {
// for all (address** p), where (is_marked(p) && _patch_base <= p && p < _patch_end) { *p += delta; }
// Patch all pointers within this region that are marked.
address* _patch_base;
address* _patch_end;
// Before patching, all pointers must point to this region.
address _valid_old_base;
address _valid_old_end;
// After patching, all pointers must point to this region.
address _valid_new_base;
address _valid_new_end;
// How much to relocate for each pointer.
intx _delta;
public:
SharedDataRelocator(address* patch_base, address* patch_end,
address valid_old_base, address valid_old_end,
address valid_new_base, address valid_new_end, intx delta) :
_patch_base(patch_base), _patch_end(patch_end),
_valid_old_base(valid_old_base), _valid_old_end(valid_old_end),
_valid_new_base(valid_new_base), _valid_new_end(valid_new_end),
_delta(delta) {
log_debug(cds, reloc)("SharedDataRelocator::_patch_base = " PTR_FORMAT, p2i(_patch_base));
log_debug(cds, reloc)("SharedDataRelocator::_patch_end = " PTR_FORMAT, p2i(_patch_end));
log_debug(cds, reloc)("SharedDataRelocator::_valid_old_base = " PTR_FORMAT, p2i(_valid_old_base));
log_debug(cds, reloc)("SharedDataRelocator::_valid_old_end = " PTR_FORMAT, p2i(_valid_old_end));
log_debug(cds, reloc)("SharedDataRelocator::_valid_new_base = " PTR_FORMAT, p2i(_valid_new_base));
log_debug(cds, reloc)("SharedDataRelocator::_valid_new_end = " PTR_FORMAT, p2i(_valid_new_end));
}
bool do_bit(size_t offset);
};
class DumpRegion {
private:
const char* _name;
char* _base;
char* _top;
char* _end;
uintx _max_delta;
bool _is_packed;
ReservedSpace* _rs;
VirtualSpace* _vs;
void commit_to(char* newtop);
public:
DumpRegion(const char* name, uintx max_delta = 0)
: _name(name), _base(NULL), _top(NULL), _end(NULL),
_max_delta(max_delta), _is_packed(false) {}
char* expand_top_to(char* newtop);
char* allocate(size_t num_bytes);
void append_intptr_t(intptr_t n, bool need_to_mark = false) NOT_CDS_RETURN;
char* base() const { return _base; }
char* top() const { return _top; }
char* end() const { return _end; }
size_t reserved() const { return _end - _base; }
size_t used() const { return _top - _base; }
bool is_packed() const { return _is_packed; }
bool is_allocatable() const {
return !is_packed() && _base != NULL;
}
void print(size_t total_bytes) const;
void print_out_of_space_msg(const char* failing_region, size_t needed_bytes);
void init(ReservedSpace* rs, VirtualSpace* vs);
void pack(DumpRegion* next = NULL);
bool contains(char* p) {
return base() <= p && p < top();
}
};
// Closure for serializing initialization data out to a data area to be
// written to the shared file.
class WriteClosure : public SerializeClosure {
private:
DumpRegion* _dump_region;
public:
WriteClosure(DumpRegion* r) {
_dump_region = r;
}
void do_ptr(void** p) {
_dump_region->append_intptr_t((intptr_t)*p, true);
}
void do_u4(u4* p) {
_dump_region->append_intptr_t((intptr_t)(*p));
}
void do_bool(bool *p) {
_dump_region->append_intptr_t((intptr_t)(*p));
}
void do_tag(int tag) {
_dump_region->append_intptr_t((intptr_t)tag);
}
void do_oop(oop* o);
void do_region(u_char* start, size_t size);
bool reading() const { return false; }
};
// Closure for serializing initialization data in from a data area
// (ptr_array) read from the shared file.
class ReadClosure : public SerializeClosure {
private:
intptr_t** _ptr_array;
inline intptr_t nextPtr() {
return *(*_ptr_array)++;
}
public:
ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
void do_ptr(void** p);
void do_u4(u4* p);
void do_bool(bool *p);
void do_tag(int tag);
void do_oop(oop *p);
void do_region(u_char* start, size_t size);
bool reading() const { return true; }
};
class ArchiveUtils {
public:
static void log_to_classlist(BootstrapInfo* bootstrap_specifier, TRAPS) NOT_CDS_RETURN;
};
#endif // SHARE_CDS_ARCHIVEUTILS_HPP
¤ Dauer der Verarbeitung: 0.3 Sekunden
(vorverarbeitet)
¤
|
Haftungshinweis
Die Informationen auf dieser Webseite wurden
nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit,
noch Qualität der bereit gestellten Informationen zugesichert.
Bemerkung:
Die farbliche Syntaxdarstellung ist noch experimentell.
|
