diff -r 000000000000 -r a61af66fc99e src/share/vm/memory/compactingPermGenGen.hpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/memory/compactingPermGenGen.hpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,248 @@ +/* + * Copyright 2003-2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +// All heaps contains a "permanent generation," containing permanent +// (reflective) objects. This is like a regular generation in some ways, +// but unlike one in others, and so is split apart. + +class PermanentGenerationSpec; + +// This is the "generation" view of a CompactingPermGen. +class CompactingPermGenGen: public OneContigSpaceCardGeneration { + friend class VMStructs; + // Abstractly, this is a subtype that gets access to protected fields. + friend class CompactingPermGen; + +private: + // Shared spaces + PermanentGenerationSpec* _spec; + size_t _shared_space_size; + VirtualSpace _ro_vs; + VirtualSpace _rw_vs; + VirtualSpace _md_vs; + VirtualSpace _mc_vs; + BlockOffsetSharedArray* _ro_bts; + BlockOffsetSharedArray* _rw_bts; + OffsetTableContigSpace* _ro_space; + OffsetTableContigSpace* _rw_space; + + // With shared spaces there is a dicotomy in the use of the + // _virtual_space of the generation. There is a portion of the + // _virtual_space that is used for the unshared part of the + // permanent generation and a portion that is reserved for the shared part. + // The _reserved field in the generation represents both the + // unshared and shared parts of the generation. The _reserved + // variable is initialized for only the unshared part but is + // later extended to include the shared part during initialization + // if shared spaces are being used. + // The reserved size for the _virtual_space for CompactingPermGenGen + // is the size of the space for the permanent generation including the + // the shared spaces. This can be seen by the use of MaxPermSize + // in the allocation of PermanentGenerationSpec. The space for the + // shared spaces is committed separately (???). + // In general at initialization only a part of the + // space for the unshared part of the permanent generation is + // committed and more is committed as the permanent generation is + // grown. In growing the permanent generation the capacity() and + // max_capacity() of the generation are used. For the permanent + // generation (implemented with a CompactingPermGenGen) the capacity() + // is taken from the capacity of the space (_the_space variable used for the + // unshared part of the generation) and the max_capacity() is based + // on the size of the _reserved variable (which includes the size of the + // shared spaces) minus the size of the shared spaces. + + // These values are redundant, but are called out separately to avoid + // going through heap/space/gen pointers for performance. + static HeapWord* unshared_bottom; + static HeapWord* unshared_end; + static HeapWord* shared_bottom; + static HeapWord* readonly_bottom; + static HeapWord* readonly_end; + static HeapWord* readwrite_bottom; + static HeapWord* readwrite_end; + static HeapWord* miscdata_bottom; + static HeapWord* miscdata_end; + static HeapWord* misccode_bottom; + static HeapWord* misccode_end; + static HeapWord* shared_end; + + // List of klassOops whose vtbl entries are used to patch others. + static void** _vtbl_list; + + // Performance Counters + GenerationCounters* _gen_counters; + CSpaceCounters* _space_counters; + + void initialize_performance_counters(); + +public: + + enum { + vtbl_list_size = 16, // number of entries in the shared space vtable list. + num_virtuals = 100 // number of virtual methods in Klass (or + // subclass) objects, or greater. + }; + + enum { + ro = 0, // read-only shared space in the heap + rw = 1, // read-write shared space in the heap + md = 2, // miscellaneous data for initializing tables, etc. + mc = 3, // miscellaneous code - vtable replacement. + n_regions = 4 + }; + + CompactingPermGenGen(ReservedSpace rs, ReservedSpace shared_rs, + size_t initial_byte_size, int level, GenRemSet* remset, + ContiguousSpace* space, + PermanentGenerationSpec* perm_spec); + + const char* name() const { + return "compacting perm gen"; + } + + const char* short_name() const { + return "Perm"; + } + + // Return the maximum capacity for the object space. This + // explicitly does not include the shared spaces. + size_t max_capacity() const; + + void update_counters(); + + void compute_new_size() { + assert(false, "Should not call this -- handled at PermGen level."); + } + + bool must_be_youngest() const { return false; } + bool must_be_oldest() const { return false; } + + OffsetTableContigSpace* ro_space() const { return _ro_space; } + OffsetTableContigSpace* rw_space() const { return _rw_space; } + VirtualSpace* md_space() { return &_md_vs; } + VirtualSpace* mc_space() { return &_mc_vs; } + ContiguousSpace* unshared_space() const { return _the_space; } + + static bool inline is_shared(const oopDesc* p) { + return (HeapWord*)p >= shared_bottom && (HeapWord*)p < shared_end; + } + // RedefineClasses note: this tester is used to check residence of + // the specified oop in the shared readonly space and not whether + // the oop is readonly. + static bool inline is_shared_readonly(const oopDesc* p) { + return (HeapWord*)p >= readonly_bottom && (HeapWord*)p < readonly_end; + } + // RedefineClasses note: this tester is used to check residence of + // the specified oop in the shared readwrite space and not whether + // the oop is readwrite. + static bool inline is_shared_readwrite(const oopDesc* p) { + return (HeapWord*)p >= readwrite_bottom && (HeapWord*)p < readwrite_end; + } + + bool is_in_unshared(const void* p) const { + return OneContigSpaceCardGeneration::is_in(p); + } + + bool is_in_shared(const void* p) const { + return p >= shared_bottom && p < shared_end; + } + + inline bool is_in(const void* p) const { + return is_in_unshared(p) || is_in_shared(p); + } + + inline PermanentGenerationSpec* spec() const { return _spec; } + inline void set_spec(PermanentGenerationSpec* spec) { _spec = spec; } + + void pre_adjust_pointers(); + void adjust_pointers(); + void space_iterate(SpaceClosure* blk, bool usedOnly = false); + void print_on(outputStream* st) const; + void younger_refs_iterate(OopsInGenClosure* blk); + void compact(); + void post_compact(); + size_t contiguous_available() const; + bool grow_by(size_t bytes); + void grow_to_reserved(); + + void clear_remembered_set(); + void invalidate_remembered_set(); + + inline bool block_is_obj(const HeapWord* addr) const { + if (addr < the_space()->top()) return true; + else if (addr < the_space()->end()) return false; + else if (addr < ro_space()->top()) return true; + else if (addr < ro_space()->end()) return false; + else if (addr < rw_space()->top()) return true; + else return false; + } + + + inline size_t block_size(const HeapWord* addr) const { + if (addr < the_space()->top()) { + return oop(addr)->size(); + } + else if (addr < the_space()->end()) { + assert(addr == the_space()->top(), "non-block head arg to block_size"); + return the_space()->end() - the_space()->top(); + } + + else if (addr < ro_space()->top()) { + return oop(addr)->size(); + } + else if (addr < ro_space()->end()) { + assert(addr == ro_space()->top(), "non-block head arg to block_size"); + return ro_space()->end() - ro_space()->top(); + } + + else if (addr < rw_space()->top()) { + return oop(addr)->size(); + } + else { + assert(addr == rw_space()->top(), "non-block head arg to block_size"); + return rw_space()->end() - rw_space()->top(); + } + } + + static void generate_vtable_methods(void** vtbl_list, + void** vtable, + char** md_top, char* md_end, + char** mc_top, char* mc_end); + + void verify(bool allow_dirty); + + // Serialization + static void initialize_oops() KERNEL_RETURN; + static void serialize_oops(SerializeOopClosure* soc); + void serialize_bts(SerializeOopClosure* soc); + + // Initiate dumping of shared file. + static jint dump_shared(GrowableArray* class_promote_order, TRAPS); + + // JVM/TI RedefineClasses() support: + // Remap the shared readonly space to shared readwrite, private if + // sharing is enabled. Simply returns true if sharing is not enabled + // or if the remapping has already been done by a prior call. + static bool remap_shared_readonly_as_readwrite(); +};