1462 lines
48 KiB
C++
1462 lines
48 KiB
C++
/*
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* Copyright 2000-2009 Sun Microsystems, Inc. All Rights Reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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* CA 95054 USA or visit www.sun.com if you need additional information or
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* have any questions.
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*
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*/
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# include "incls/_precompiled.incl"
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# include "incls/_genCollectedHeap.cpp.incl"
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GenCollectedHeap* GenCollectedHeap::_gch;
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NOT_PRODUCT(size_t GenCollectedHeap::_skip_header_HeapWords = 0;)
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// The set of potentially parallel tasks in strong root scanning.
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enum GCH_process_strong_roots_tasks {
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// We probably want to parallelize both of these internally, but for now...
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GCH_PS_younger_gens,
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// Leave this one last.
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GCH_PS_NumElements
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};
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GenCollectedHeap::GenCollectedHeap(GenCollectorPolicy *policy) :
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SharedHeap(policy),
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_gen_policy(policy),
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_gen_process_strong_tasks(new SubTasksDone(GCH_PS_NumElements)),
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_full_collections_completed(0)
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{
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if (_gen_process_strong_tasks == NULL ||
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!_gen_process_strong_tasks->valid()) {
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vm_exit_during_initialization("Failed necessary allocation.");
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}
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assert(policy != NULL, "Sanity check");
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_preloading_shared_classes = false;
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}
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jint GenCollectedHeap::initialize() {
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CollectedHeap::pre_initialize();
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int i;
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_n_gens = gen_policy()->number_of_generations();
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// While there are no constraints in the GC code that HeapWordSize
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// be any particular value, there are multiple other areas in the
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// system which believe this to be true (e.g. oop->object_size in some
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// cases incorrectly returns the size in wordSize units rather than
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// HeapWordSize).
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guarantee(HeapWordSize == wordSize, "HeapWordSize must equal wordSize");
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// The heap must be at least as aligned as generations.
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size_t alignment = Generation::GenGrain;
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_gen_specs = gen_policy()->generations();
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PermanentGenerationSpec *perm_gen_spec =
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collector_policy()->permanent_generation();
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// Make sure the sizes are all aligned.
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for (i = 0; i < _n_gens; i++) {
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_gen_specs[i]->align(alignment);
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}
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perm_gen_spec->align(alignment);
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// If we are dumping the heap, then allocate a wasted block of address
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// space in order to push the heap to a lower address. This extra
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// address range allows for other (or larger) libraries to be loaded
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// without them occupying the space required for the shared spaces.
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if (DumpSharedSpaces) {
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uintx reserved = 0;
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uintx block_size = 64*1024*1024;
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while (reserved < SharedDummyBlockSize) {
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char* dummy = os::reserve_memory(block_size);
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reserved += block_size;
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}
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}
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// Allocate space for the heap.
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char* heap_address;
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size_t total_reserved = 0;
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int n_covered_regions = 0;
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ReservedSpace heap_rs(0);
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heap_address = allocate(alignment, perm_gen_spec, &total_reserved,
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&n_covered_regions, &heap_rs);
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if (UseSharedSpaces) {
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if (!heap_rs.is_reserved() || heap_address != heap_rs.base()) {
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if (heap_rs.is_reserved()) {
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heap_rs.release();
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}
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FileMapInfo* mapinfo = FileMapInfo::current_info();
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mapinfo->fail_continue("Unable to reserve shared region.");
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allocate(alignment, perm_gen_spec, &total_reserved, &n_covered_regions,
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&heap_rs);
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}
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}
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if (!heap_rs.is_reserved()) {
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vm_shutdown_during_initialization(
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"Could not reserve enough space for object heap");
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return JNI_ENOMEM;
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}
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_reserved = MemRegion((HeapWord*)heap_rs.base(),
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(HeapWord*)(heap_rs.base() + heap_rs.size()));
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// It is important to do this in a way such that concurrent readers can't
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// temporarily think somethings in the heap. (Seen this happen in asserts.)
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_reserved.set_word_size(0);
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_reserved.set_start((HeapWord*)heap_rs.base());
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size_t actual_heap_size = heap_rs.size() - perm_gen_spec->misc_data_size()
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- perm_gen_spec->misc_code_size();
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_reserved.set_end((HeapWord*)(heap_rs.base() + actual_heap_size));
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_rem_set = collector_policy()->create_rem_set(_reserved, n_covered_regions);
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set_barrier_set(rem_set()->bs());
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_gch = this;
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for (i = 0; i < _n_gens; i++) {
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ReservedSpace this_rs = heap_rs.first_part(_gen_specs[i]->max_size(),
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UseSharedSpaces, UseSharedSpaces);
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_gens[i] = _gen_specs[i]->init(this_rs, i, rem_set());
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heap_rs = heap_rs.last_part(_gen_specs[i]->max_size());
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}
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_perm_gen = perm_gen_spec->init(heap_rs, PermSize, rem_set());
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clear_incremental_collection_will_fail();
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clear_last_incremental_collection_failed();
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#ifndef SERIALGC
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// If we are running CMS, create the collector responsible
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// for collecting the CMS generations.
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if (collector_policy()->is_concurrent_mark_sweep_policy()) {
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bool success = create_cms_collector();
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if (!success) return JNI_ENOMEM;
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}
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#endif // SERIALGC
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return JNI_OK;
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}
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char* GenCollectedHeap::allocate(size_t alignment,
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PermanentGenerationSpec* perm_gen_spec,
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size_t* _total_reserved,
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int* _n_covered_regions,
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ReservedSpace* heap_rs){
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const char overflow_msg[] = "The size of the object heap + VM data exceeds "
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"the maximum representable size";
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// Now figure out the total size.
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size_t total_reserved = 0;
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int n_covered_regions = 0;
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const size_t pageSize = UseLargePages ?
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os::large_page_size() : os::vm_page_size();
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for (int i = 0; i < _n_gens; i++) {
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total_reserved += _gen_specs[i]->max_size();
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if (total_reserved < _gen_specs[i]->max_size()) {
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vm_exit_during_initialization(overflow_msg);
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}
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n_covered_regions += _gen_specs[i]->n_covered_regions();
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}
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assert(total_reserved % pageSize == 0, "Gen size");
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total_reserved += perm_gen_spec->max_size();
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assert(total_reserved % pageSize == 0, "Perm Gen size");
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if (total_reserved < perm_gen_spec->max_size()) {
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vm_exit_during_initialization(overflow_msg);
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}
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n_covered_regions += perm_gen_spec->n_covered_regions();
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// Add the size of the data area which shares the same reserved area
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// as the heap, but which is not actually part of the heap.
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size_t s = perm_gen_spec->misc_data_size() + perm_gen_spec->misc_code_size();
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total_reserved += s;
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if (total_reserved < s) {
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vm_exit_during_initialization(overflow_msg);
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}
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if (UseLargePages) {
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assert(total_reserved != 0, "total_reserved cannot be 0");
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total_reserved = round_to(total_reserved, os::large_page_size());
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if (total_reserved < os::large_page_size()) {
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vm_exit_during_initialization(overflow_msg);
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}
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}
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// Calculate the address at which the heap must reside in order for
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// the shared data to be at the required address.
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char* heap_address;
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if (UseSharedSpaces) {
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// Calculate the address of the first word beyond the heap.
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FileMapInfo* mapinfo = FileMapInfo::current_info();
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int lr = CompactingPermGenGen::n_regions - 1;
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size_t capacity = align_size_up(mapinfo->space_capacity(lr), alignment);
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heap_address = mapinfo->region_base(lr) + capacity;
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// Calculate the address of the first word of the heap.
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heap_address -= total_reserved;
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} else {
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heap_address = NULL; // any address will do.
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if (UseCompressedOops) {
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heap_address = Universe::preferred_heap_base(total_reserved, Universe::UnscaledNarrowOop);
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*_total_reserved = total_reserved;
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*_n_covered_regions = n_covered_regions;
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*heap_rs = ReservedHeapSpace(total_reserved, alignment,
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UseLargePages, heap_address);
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if (heap_address != NULL && !heap_rs->is_reserved()) {
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// Failed to reserve at specified address - the requested memory
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// region is taken already, for example, by 'java' launcher.
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// Try again to reserver heap higher.
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heap_address = Universe::preferred_heap_base(total_reserved, Universe::ZeroBasedNarrowOop);
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*heap_rs = ReservedHeapSpace(total_reserved, alignment,
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UseLargePages, heap_address);
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if (heap_address != NULL && !heap_rs->is_reserved()) {
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// Failed to reserve at specified address again - give up.
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heap_address = Universe::preferred_heap_base(total_reserved, Universe::HeapBasedNarrowOop);
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assert(heap_address == NULL, "");
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*heap_rs = ReservedHeapSpace(total_reserved, alignment,
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UseLargePages, heap_address);
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}
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}
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return heap_address;
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}
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}
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*_total_reserved = total_reserved;
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*_n_covered_regions = n_covered_regions;
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*heap_rs = ReservedHeapSpace(total_reserved, alignment,
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UseLargePages, heap_address);
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return heap_address;
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}
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void GenCollectedHeap::post_initialize() {
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SharedHeap::post_initialize();
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TwoGenerationCollectorPolicy *policy =
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(TwoGenerationCollectorPolicy *)collector_policy();
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guarantee(policy->is_two_generation_policy(), "Illegal policy type");
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DefNewGeneration* def_new_gen = (DefNewGeneration*) get_gen(0);
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assert(def_new_gen->kind() == Generation::DefNew ||
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def_new_gen->kind() == Generation::ParNew ||
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def_new_gen->kind() == Generation::ASParNew,
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"Wrong generation kind");
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Generation* old_gen = get_gen(1);
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assert(old_gen->kind() == Generation::ConcurrentMarkSweep ||
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old_gen->kind() == Generation::ASConcurrentMarkSweep ||
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old_gen->kind() == Generation::MarkSweepCompact,
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"Wrong generation kind");
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policy->initialize_size_policy(def_new_gen->eden()->capacity(),
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old_gen->capacity(),
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def_new_gen->from()->capacity());
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policy->initialize_gc_policy_counters();
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}
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void GenCollectedHeap::ref_processing_init() {
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SharedHeap::ref_processing_init();
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for (int i = 0; i < _n_gens; i++) {
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_gens[i]->ref_processor_init();
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}
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}
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size_t GenCollectedHeap::capacity() const {
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size_t res = 0;
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for (int i = 0; i < _n_gens; i++) {
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res += _gens[i]->capacity();
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}
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return res;
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}
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size_t GenCollectedHeap::used() const {
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size_t res = 0;
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for (int i = 0; i < _n_gens; i++) {
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res += _gens[i]->used();
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}
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return res;
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}
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// Save the "used_region" for generations level and lower,
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// and, if perm is true, for perm gen.
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void GenCollectedHeap::save_used_regions(int level, bool perm) {
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assert(level < _n_gens, "Illegal level parameter");
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for (int i = level; i >= 0; i--) {
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_gens[i]->save_used_region();
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}
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if (perm) {
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perm_gen()->save_used_region();
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}
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}
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size_t GenCollectedHeap::max_capacity() const {
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size_t res = 0;
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for (int i = 0; i < _n_gens; i++) {
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res += _gens[i]->max_capacity();
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}
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return res;
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}
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// Update the _full_collections_completed counter
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// at the end of a stop-world full GC.
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unsigned int GenCollectedHeap::update_full_collections_completed() {
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MonitorLockerEx ml(FullGCCount_lock, Mutex::_no_safepoint_check_flag);
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assert(_full_collections_completed <= _total_full_collections,
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"Can't complete more collections than were started");
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_full_collections_completed = _total_full_collections;
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ml.notify_all();
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return _full_collections_completed;
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}
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// Update the _full_collections_completed counter, as appropriate,
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// at the end of a concurrent GC cycle. Note the conditional update
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// below to allow this method to be called by a concurrent collector
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// without synchronizing in any manner with the VM thread (which
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// may already have initiated a STW full collection "concurrently").
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unsigned int GenCollectedHeap::update_full_collections_completed(unsigned int count) {
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MonitorLockerEx ml(FullGCCount_lock, Mutex::_no_safepoint_check_flag);
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assert((_full_collections_completed <= _total_full_collections) &&
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(count <= _total_full_collections),
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"Can't complete more collections than were started");
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if (count > _full_collections_completed) {
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_full_collections_completed = count;
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ml.notify_all();
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}
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return _full_collections_completed;
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}
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#ifndef PRODUCT
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// Override of memory state checking method in CollectedHeap:
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// Some collectors (CMS for example) can't have badHeapWordVal written
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// in the first two words of an object. (For instance , in the case of
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// CMS these words hold state used to synchronize between certain
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// (concurrent) GC steps and direct allocating mutators.)
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// The skip_header_HeapWords() method below, allows us to skip
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// over the requisite number of HeapWord's. Note that (for
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// generational collectors) this means that those many words are
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// skipped in each object, irrespective of the generation in which
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// that object lives. The resultant loss of precision seems to be
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// harmless and the pain of avoiding that imprecision appears somewhat
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// higher than we are prepared to pay for such rudimentary debugging
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// support.
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void GenCollectedHeap::check_for_non_bad_heap_word_value(HeapWord* addr,
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size_t size) {
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if (CheckMemoryInitialization && ZapUnusedHeapArea) {
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// We are asked to check a size in HeapWords,
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// but the memory is mangled in juint words.
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juint* start = (juint*) (addr + skip_header_HeapWords());
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juint* end = (juint*) (addr + size);
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for (juint* slot = start; slot < end; slot += 1) {
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assert(*slot == badHeapWordVal,
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"Found non badHeapWordValue in pre-allocation check");
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}
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}
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}
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#endif
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HeapWord* GenCollectedHeap::attempt_allocation(size_t size,
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bool is_tlab,
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bool first_only) {
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HeapWord* res;
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for (int i = 0; i < _n_gens; i++) {
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if (_gens[i]->should_allocate(size, is_tlab)) {
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res = _gens[i]->allocate(size, is_tlab);
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if (res != NULL) return res;
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else if (first_only) break;
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}
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}
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// Otherwise...
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return NULL;
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}
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HeapWord* GenCollectedHeap::mem_allocate(size_t size,
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bool is_large_noref,
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bool is_tlab,
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bool* gc_overhead_limit_was_exceeded) {
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return collector_policy()->mem_allocate_work(size,
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is_tlab,
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gc_overhead_limit_was_exceeded);
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}
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bool GenCollectedHeap::must_clear_all_soft_refs() {
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return _gc_cause == GCCause::_last_ditch_collection;
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}
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bool GenCollectedHeap::should_do_concurrent_full_gc(GCCause::Cause cause) {
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return (cause == GCCause::_java_lang_system_gc ||
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cause == GCCause::_gc_locker) &&
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UseConcMarkSweepGC && ExplicitGCInvokesConcurrent;
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}
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void GenCollectedHeap::do_collection(bool full,
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bool clear_all_soft_refs,
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size_t size,
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bool is_tlab,
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int max_level) {
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bool prepared_for_verification = false;
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ResourceMark rm;
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DEBUG_ONLY(Thread* my_thread = Thread::current();)
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assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
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assert(my_thread->is_VM_thread() ||
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my_thread->is_ConcurrentGC_thread(),
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"incorrect thread type capability");
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assert(Heap_lock->is_locked(), "the requesting thread should have the Heap_lock");
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guarantee(!is_gc_active(), "collection is not reentrant");
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assert(max_level < n_gens(), "sanity check");
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if (GC_locker::check_active_before_gc()) {
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return; // GC is disabled (e.g. JNI GetXXXCritical operation)
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}
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const size_t perm_prev_used = perm_gen()->used();
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if (PrintHeapAtGC) {
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Universe::print_heap_before_gc();
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if (Verbose) {
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gclog_or_tty->print_cr("GC Cause: %s", GCCause::to_string(gc_cause()));
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}
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}
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{
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FlagSetting fl(_is_gc_active, true);
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bool complete = full && (max_level == (n_gens()-1));
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const char* gc_cause_str = "GC ";
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if (complete) {
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GCCause::Cause cause = gc_cause();
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if (cause == GCCause::_java_lang_system_gc) {
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gc_cause_str = "Full GC (System) ";
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} else {
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gc_cause_str = "Full GC ";
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}
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}
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gclog_or_tty->date_stamp(PrintGC && PrintGCDateStamps);
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TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty);
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TraceTime t(gc_cause_str, PrintGCDetails, false, gclog_or_tty);
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gc_prologue(complete);
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increment_total_collections(complete);
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size_t gch_prev_used = used();
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int starting_level = 0;
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if (full) {
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// Search for the oldest generation which will collect all younger
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// generations, and start collection loop there.
|
|
for (int i = max_level; i >= 0; i--) {
|
|
if (_gens[i]->full_collects_younger_generations()) {
|
|
starting_level = i;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
bool must_restore_marks_for_biased_locking = false;
|
|
|
|
int max_level_collected = starting_level;
|
|
for (int i = starting_level; i <= max_level; i++) {
|
|
if (_gens[i]->should_collect(full, size, is_tlab)) {
|
|
if (i == n_gens() - 1) { // a major collection is to happen
|
|
if (!complete) {
|
|
// The full_collections increment was missed above.
|
|
increment_total_full_collections();
|
|
}
|
|
pre_full_gc_dump(); // do any pre full gc dumps
|
|
}
|
|
// Timer for individual generations. Last argument is false: no CR
|
|
TraceTime t1(_gens[i]->short_name(), PrintGCDetails, false, gclog_or_tty);
|
|
TraceCollectorStats tcs(_gens[i]->counters());
|
|
TraceMemoryManagerStats tmms(_gens[i]->kind());
|
|
|
|
size_t prev_used = _gens[i]->used();
|
|
_gens[i]->stat_record()->invocations++;
|
|
_gens[i]->stat_record()->accumulated_time.start();
|
|
|
|
// Must be done anew before each collection because
|
|
// a previous collection will do mangling and will
|
|
// change top of some spaces.
|
|
record_gen_tops_before_GC();
|
|
|
|
if (PrintGC && Verbose) {
|
|
gclog_or_tty->print("level=%d invoke=%d size=" SIZE_FORMAT,
|
|
i,
|
|
_gens[i]->stat_record()->invocations,
|
|
size*HeapWordSize);
|
|
}
|
|
|
|
if (VerifyBeforeGC && i >= VerifyGCLevel &&
|
|
total_collections() >= VerifyGCStartAt) {
|
|
HandleMark hm; // Discard invalid handles created during verification
|
|
if (!prepared_for_verification) {
|
|
prepare_for_verify();
|
|
prepared_for_verification = true;
|
|
}
|
|
gclog_or_tty->print(" VerifyBeforeGC:");
|
|
Universe::verify(true);
|
|
}
|
|
COMPILER2_PRESENT(DerivedPointerTable::clear());
|
|
|
|
if (!must_restore_marks_for_biased_locking &&
|
|
_gens[i]->performs_in_place_marking()) {
|
|
// We perform this mark word preservation work lazily
|
|
// because it's only at this point that we know whether we
|
|
// absolutely have to do it; we want to avoid doing it for
|
|
// scavenge-only collections where it's unnecessary
|
|
must_restore_marks_for_biased_locking = true;
|
|
BiasedLocking::preserve_marks();
|
|
}
|
|
|
|
// Do collection work
|
|
{
|
|
// Note on ref discovery: For what appear to be historical reasons,
|
|
// GCH enables and disabled (by enqueing) refs discovery.
|
|
// In the future this should be moved into the generation's
|
|
// collect method so that ref discovery and enqueueing concerns
|
|
// are local to a generation. The collect method could return
|
|
// an appropriate indication in the case that notification on
|
|
// the ref lock was needed. This will make the treatment of
|
|
// weak refs more uniform (and indeed remove such concerns
|
|
// from GCH). XXX
|
|
|
|
HandleMark hm; // Discard invalid handles created during gc
|
|
save_marks(); // save marks for all gens
|
|
// We want to discover references, but not process them yet.
|
|
// This mode is disabled in process_discovered_references if the
|
|
// generation does some collection work, or in
|
|
// enqueue_discovered_references if the generation returns
|
|
// without doing any work.
|
|
ReferenceProcessor* rp = _gens[i]->ref_processor();
|
|
// If the discovery of ("weak") refs in this generation is
|
|
// atomic wrt other collectors in this configuration, we
|
|
// are guaranteed to have empty discovered ref lists.
|
|
if (rp->discovery_is_atomic()) {
|
|
rp->verify_no_references_recorded();
|
|
rp->enable_discovery();
|
|
rp->setup_policy(clear_all_soft_refs);
|
|
} else {
|
|
// collect() below will enable discovery as appropriate
|
|
}
|
|
_gens[i]->collect(full, clear_all_soft_refs, size, is_tlab);
|
|
if (!rp->enqueuing_is_done()) {
|
|
rp->enqueue_discovered_references();
|
|
} else {
|
|
rp->set_enqueuing_is_done(false);
|
|
}
|
|
rp->verify_no_references_recorded();
|
|
}
|
|
max_level_collected = i;
|
|
|
|
// Determine if allocation request was met.
|
|
if (size > 0) {
|
|
if (!is_tlab || _gens[i]->supports_tlab_allocation()) {
|
|
if (size*HeapWordSize <= _gens[i]->unsafe_max_alloc_nogc()) {
|
|
size = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
COMPILER2_PRESENT(DerivedPointerTable::update_pointers());
|
|
|
|
_gens[i]->stat_record()->accumulated_time.stop();
|
|
|
|
update_gc_stats(i, full);
|
|
|
|
if (VerifyAfterGC && i >= VerifyGCLevel &&
|
|
total_collections() >= VerifyGCStartAt) {
|
|
HandleMark hm; // Discard invalid handles created during verification
|
|
gclog_or_tty->print(" VerifyAfterGC:");
|
|
Universe::verify(false);
|
|
}
|
|
|
|
if (PrintGCDetails) {
|
|
gclog_or_tty->print(":");
|
|
_gens[i]->print_heap_change(prev_used);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Update "complete" boolean wrt what actually transpired --
|
|
// for instance, a promotion failure could have led to
|
|
// a whole heap collection.
|
|
complete = complete || (max_level_collected == n_gens() - 1);
|
|
|
|
if (complete) { // We did a "major" collection
|
|
post_full_gc_dump(); // do any post full gc dumps
|
|
}
|
|
|
|
if (PrintGCDetails) {
|
|
print_heap_change(gch_prev_used);
|
|
|
|
// Print perm gen info for full GC with PrintGCDetails flag.
|
|
if (complete) {
|
|
print_perm_heap_change(perm_prev_used);
|
|
}
|
|
}
|
|
|
|
for (int j = max_level_collected; j >= 0; j -= 1) {
|
|
// Adjust generation sizes.
|
|
_gens[j]->compute_new_size();
|
|
}
|
|
|
|
if (complete) {
|
|
// Ask the permanent generation to adjust size for full collections
|
|
perm()->compute_new_size();
|
|
update_full_collections_completed();
|
|
}
|
|
|
|
// Track memory usage and detect low memory after GC finishes
|
|
MemoryService::track_memory_usage();
|
|
|
|
gc_epilogue(complete);
|
|
|
|
if (must_restore_marks_for_biased_locking) {
|
|
BiasedLocking::restore_marks();
|
|
}
|
|
}
|
|
|
|
AdaptiveSizePolicy* sp = gen_policy()->size_policy();
|
|
AdaptiveSizePolicyOutput(sp, total_collections());
|
|
|
|
if (PrintHeapAtGC) {
|
|
Universe::print_heap_after_gc();
|
|
}
|
|
|
|
#ifdef TRACESPINNING
|
|
ParallelTaskTerminator::print_termination_counts();
|
|
#endif
|
|
|
|
if (ExitAfterGCNum > 0 && total_collections() == ExitAfterGCNum) {
|
|
tty->print_cr("Stopping after GC #%d", ExitAfterGCNum);
|
|
vm_exit(-1);
|
|
}
|
|
}
|
|
|
|
HeapWord* GenCollectedHeap::satisfy_failed_allocation(size_t size, bool is_tlab) {
|
|
return collector_policy()->satisfy_failed_allocation(size, is_tlab);
|
|
}
|
|
|
|
void GenCollectedHeap::set_par_threads(int t) {
|
|
SharedHeap::set_par_threads(t);
|
|
_gen_process_strong_tasks->set_par_threads(t);
|
|
}
|
|
|
|
class AssertIsPermClosure: public OopClosure {
|
|
public:
|
|
void do_oop(oop* p) {
|
|
assert((*p) == NULL || (*p)->is_perm(), "Referent should be perm.");
|
|
}
|
|
void do_oop(narrowOop* p) { ShouldNotReachHere(); }
|
|
};
|
|
static AssertIsPermClosure assert_is_perm_closure;
|
|
|
|
void GenCollectedHeap::
|
|
gen_process_strong_roots(int level,
|
|
bool younger_gens_as_roots,
|
|
bool activate_scope,
|
|
bool collecting_perm_gen,
|
|
SharedHeap::ScanningOption so,
|
|
OopsInGenClosure* not_older_gens,
|
|
bool do_code_roots,
|
|
OopsInGenClosure* older_gens) {
|
|
// General strong roots.
|
|
|
|
if (!do_code_roots) {
|
|
SharedHeap::process_strong_roots(activate_scope, collecting_perm_gen, so,
|
|
not_older_gens, NULL, older_gens);
|
|
} else {
|
|
bool do_code_marking = (activate_scope || nmethod::oops_do_marking_is_active());
|
|
CodeBlobToOopClosure code_roots(not_older_gens, /*do_marking=*/ do_code_marking);
|
|
SharedHeap::process_strong_roots(activate_scope, collecting_perm_gen, so,
|
|
not_older_gens, &code_roots, older_gens);
|
|
}
|
|
|
|
if (younger_gens_as_roots) {
|
|
if (!_gen_process_strong_tasks->is_task_claimed(GCH_PS_younger_gens)) {
|
|
for (int i = 0; i < level; i++) {
|
|
not_older_gens->set_generation(_gens[i]);
|
|
_gens[i]->oop_iterate(not_older_gens);
|
|
}
|
|
not_older_gens->reset_generation();
|
|
}
|
|
}
|
|
// When collection is parallel, all threads get to cooperate to do
|
|
// older-gen scanning.
|
|
for (int i = level+1; i < _n_gens; i++) {
|
|
older_gens->set_generation(_gens[i]);
|
|
rem_set()->younger_refs_iterate(_gens[i], older_gens);
|
|
older_gens->reset_generation();
|
|
}
|
|
|
|
_gen_process_strong_tasks->all_tasks_completed();
|
|
}
|
|
|
|
void GenCollectedHeap::gen_process_weak_roots(OopClosure* root_closure,
|
|
CodeBlobClosure* code_roots,
|
|
OopClosure* non_root_closure) {
|
|
SharedHeap::process_weak_roots(root_closure, code_roots, non_root_closure);
|
|
// "Local" "weak" refs
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->ref_processor()->weak_oops_do(root_closure);
|
|
}
|
|
}
|
|
|
|
#define GCH_SINCE_SAVE_MARKS_ITERATE_DEFN(OopClosureType, nv_suffix) \
|
|
void GenCollectedHeap:: \
|
|
oop_since_save_marks_iterate(int level, \
|
|
OopClosureType* cur, \
|
|
OopClosureType* older) { \
|
|
_gens[level]->oop_since_save_marks_iterate##nv_suffix(cur); \
|
|
for (int i = level+1; i < n_gens(); i++) { \
|
|
_gens[i]->oop_since_save_marks_iterate##nv_suffix(older); \
|
|
} \
|
|
perm_gen()->oop_since_save_marks_iterate##nv_suffix(older); \
|
|
}
|
|
|
|
ALL_SINCE_SAVE_MARKS_CLOSURES(GCH_SINCE_SAVE_MARKS_ITERATE_DEFN)
|
|
|
|
#undef GCH_SINCE_SAVE_MARKS_ITERATE_DEFN
|
|
|
|
bool GenCollectedHeap::no_allocs_since_save_marks(int level) {
|
|
for (int i = level; i < _n_gens; i++) {
|
|
if (!_gens[i]->no_allocs_since_save_marks()) return false;
|
|
}
|
|
return perm_gen()->no_allocs_since_save_marks();
|
|
}
|
|
|
|
bool GenCollectedHeap::supports_inline_contig_alloc() const {
|
|
return _gens[0]->supports_inline_contig_alloc();
|
|
}
|
|
|
|
HeapWord** GenCollectedHeap::top_addr() const {
|
|
return _gens[0]->top_addr();
|
|
}
|
|
|
|
HeapWord** GenCollectedHeap::end_addr() const {
|
|
return _gens[0]->end_addr();
|
|
}
|
|
|
|
size_t GenCollectedHeap::unsafe_max_alloc() {
|
|
return _gens[0]->unsafe_max_alloc_nogc();
|
|
}
|
|
|
|
// public collection interfaces
|
|
|
|
void GenCollectedHeap::collect(GCCause::Cause cause) {
|
|
if (should_do_concurrent_full_gc(cause)) {
|
|
#ifndef SERIALGC
|
|
// mostly concurrent full collection
|
|
collect_mostly_concurrent(cause);
|
|
#else // SERIALGC
|
|
ShouldNotReachHere();
|
|
#endif // SERIALGC
|
|
} else {
|
|
#ifdef ASSERT
|
|
if (cause == GCCause::_scavenge_alot) {
|
|
// minor collection only
|
|
collect(cause, 0);
|
|
} else {
|
|
// Stop-the-world full collection
|
|
collect(cause, n_gens() - 1);
|
|
}
|
|
#else
|
|
// Stop-the-world full collection
|
|
collect(cause, n_gens() - 1);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
void GenCollectedHeap::collect(GCCause::Cause cause, int max_level) {
|
|
// The caller doesn't have the Heap_lock
|
|
assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
|
|
MutexLocker ml(Heap_lock);
|
|
collect_locked(cause, max_level);
|
|
}
|
|
|
|
// This interface assumes that it's being called by the
|
|
// vm thread. It collects the heap assuming that the
|
|
// heap lock is already held and that we are executing in
|
|
// the context of the vm thread.
|
|
void GenCollectedHeap::collect_as_vm_thread(GCCause::Cause cause) {
|
|
assert(Thread::current()->is_VM_thread(), "Precondition#1");
|
|
assert(Heap_lock->is_locked(), "Precondition#2");
|
|
GCCauseSetter gcs(this, cause);
|
|
switch (cause) {
|
|
case GCCause::_heap_inspection:
|
|
case GCCause::_heap_dump: {
|
|
HandleMark hm;
|
|
do_full_collection(false, // don't clear all soft refs
|
|
n_gens() - 1);
|
|
break;
|
|
}
|
|
default: // XXX FIX ME
|
|
ShouldNotReachHere(); // Unexpected use of this function
|
|
}
|
|
}
|
|
|
|
void GenCollectedHeap::collect_locked(GCCause::Cause cause) {
|
|
// The caller has the Heap_lock
|
|
assert(Heap_lock->owned_by_self(), "this thread should own the Heap_lock");
|
|
collect_locked(cause, n_gens() - 1);
|
|
}
|
|
|
|
// this is the private collection interface
|
|
// The Heap_lock is expected to be held on entry.
|
|
|
|
void GenCollectedHeap::collect_locked(GCCause::Cause cause, int max_level) {
|
|
if (_preloading_shared_classes) {
|
|
warning("\nThe permanent generation is not large enough to preload "
|
|
"requested classes.\nUse -XX:PermSize= to increase the initial "
|
|
"size of the permanent generation.\n");
|
|
vm_exit(2);
|
|
}
|
|
// Read the GC count while holding the Heap_lock
|
|
unsigned int gc_count_before = total_collections();
|
|
unsigned int full_gc_count_before = total_full_collections();
|
|
{
|
|
MutexUnlocker mu(Heap_lock); // give up heap lock, execute gets it back
|
|
VM_GenCollectFull op(gc_count_before, full_gc_count_before,
|
|
cause, max_level);
|
|
VMThread::execute(&op);
|
|
}
|
|
}
|
|
|
|
#ifndef SERIALGC
|
|
bool GenCollectedHeap::create_cms_collector() {
|
|
|
|
assert(((_gens[1]->kind() == Generation::ConcurrentMarkSweep) ||
|
|
(_gens[1]->kind() == Generation::ASConcurrentMarkSweep)) &&
|
|
_perm_gen->as_gen()->kind() == Generation::ConcurrentMarkSweep,
|
|
"Unexpected generation kinds");
|
|
// Skip two header words in the block content verification
|
|
NOT_PRODUCT(_skip_header_HeapWords = CMSCollector::skip_header_HeapWords();)
|
|
CMSCollector* collector = new CMSCollector(
|
|
(ConcurrentMarkSweepGeneration*)_gens[1],
|
|
(ConcurrentMarkSweepGeneration*)_perm_gen->as_gen(),
|
|
_rem_set->as_CardTableRS(),
|
|
(ConcurrentMarkSweepPolicy*) collector_policy());
|
|
|
|
if (collector == NULL || !collector->completed_initialization()) {
|
|
if (collector) {
|
|
delete collector; // Be nice in embedded situation
|
|
}
|
|
vm_shutdown_during_initialization("Could not create CMS collector");
|
|
return false;
|
|
}
|
|
return true; // success
|
|
}
|
|
|
|
void GenCollectedHeap::collect_mostly_concurrent(GCCause::Cause cause) {
|
|
assert(!Heap_lock->owned_by_self(), "Should not own Heap_lock");
|
|
|
|
MutexLocker ml(Heap_lock);
|
|
// Read the GC counts while holding the Heap_lock
|
|
unsigned int full_gc_count_before = total_full_collections();
|
|
unsigned int gc_count_before = total_collections();
|
|
{
|
|
MutexUnlocker mu(Heap_lock);
|
|
VM_GenCollectFullConcurrent op(gc_count_before, full_gc_count_before, cause);
|
|
VMThread::execute(&op);
|
|
}
|
|
}
|
|
#endif // SERIALGC
|
|
|
|
|
|
void GenCollectedHeap::do_full_collection(bool clear_all_soft_refs,
|
|
int max_level) {
|
|
int local_max_level;
|
|
if (!incremental_collection_will_fail() &&
|
|
gc_cause() == GCCause::_gc_locker) {
|
|
local_max_level = 0;
|
|
} else {
|
|
local_max_level = max_level;
|
|
}
|
|
|
|
do_collection(true /* full */,
|
|
clear_all_soft_refs /* clear_all_soft_refs */,
|
|
0 /* size */,
|
|
false /* is_tlab */,
|
|
local_max_level /* max_level */);
|
|
// Hack XXX FIX ME !!!
|
|
// A scavenge may not have been attempted, or may have
|
|
// been attempted and failed, because the old gen was too full
|
|
if (local_max_level == 0 && gc_cause() == GCCause::_gc_locker &&
|
|
incremental_collection_will_fail()) {
|
|
if (PrintGCDetails) {
|
|
gclog_or_tty->print_cr("GC locker: Trying a full collection "
|
|
"because scavenge failed");
|
|
}
|
|
// This time allow the old gen to be collected as well
|
|
do_collection(true /* full */,
|
|
clear_all_soft_refs /* clear_all_soft_refs */,
|
|
0 /* size */,
|
|
false /* is_tlab */,
|
|
n_gens() - 1 /* max_level */);
|
|
}
|
|
}
|
|
|
|
// Returns "TRUE" iff "p" points into the allocated area of the heap.
|
|
bool GenCollectedHeap::is_in(const void* p) const {
|
|
#ifndef ASSERT
|
|
guarantee(VerifyBeforeGC ||
|
|
VerifyDuringGC ||
|
|
VerifyBeforeExit ||
|
|
PrintAssembly ||
|
|
tty->count() != 0 || // already printing
|
|
VerifyAfterGC, "too expensive");
|
|
#endif
|
|
// This might be sped up with a cache of the last generation that
|
|
// answered yes.
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
if (_gens[i]->is_in(p)) return true;
|
|
}
|
|
if (_perm_gen->as_gen()->is_in(p)) return true;
|
|
// Otherwise...
|
|
return false;
|
|
}
|
|
|
|
// Returns "TRUE" iff "p" points into the allocated area of the heap.
|
|
bool GenCollectedHeap::is_in_youngest(void* p) {
|
|
return _gens[0]->is_in(p);
|
|
}
|
|
|
|
void GenCollectedHeap::oop_iterate(OopClosure* cl) {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->oop_iterate(cl);
|
|
}
|
|
}
|
|
|
|
void GenCollectedHeap::oop_iterate(MemRegion mr, OopClosure* cl) {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->oop_iterate(mr, cl);
|
|
}
|
|
}
|
|
|
|
void GenCollectedHeap::object_iterate(ObjectClosure* cl) {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->object_iterate(cl);
|
|
}
|
|
perm_gen()->object_iterate(cl);
|
|
}
|
|
|
|
void GenCollectedHeap::safe_object_iterate(ObjectClosure* cl) {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->safe_object_iterate(cl);
|
|
}
|
|
perm_gen()->safe_object_iterate(cl);
|
|
}
|
|
|
|
void GenCollectedHeap::object_iterate_since_last_GC(ObjectClosure* cl) {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->object_iterate_since_last_GC(cl);
|
|
}
|
|
}
|
|
|
|
Space* GenCollectedHeap::space_containing(const void* addr) const {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
Space* res = _gens[i]->space_containing(addr);
|
|
if (res != NULL) return res;
|
|
}
|
|
Space* res = perm_gen()->space_containing(addr);
|
|
if (res != NULL) return res;
|
|
// Otherwise...
|
|
assert(false, "Could not find containing space");
|
|
return NULL;
|
|
}
|
|
|
|
|
|
HeapWord* GenCollectedHeap::block_start(const void* addr) const {
|
|
assert(is_in_reserved(addr), "block_start of address outside of heap");
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
if (_gens[i]->is_in_reserved(addr)) {
|
|
assert(_gens[i]->is_in(addr),
|
|
"addr should be in allocated part of generation");
|
|
return _gens[i]->block_start(addr);
|
|
}
|
|
}
|
|
if (perm_gen()->is_in_reserved(addr)) {
|
|
assert(perm_gen()->is_in(addr),
|
|
"addr should be in allocated part of perm gen");
|
|
return perm_gen()->block_start(addr);
|
|
}
|
|
assert(false, "Some generation should contain the address");
|
|
return NULL;
|
|
}
|
|
|
|
size_t GenCollectedHeap::block_size(const HeapWord* addr) const {
|
|
assert(is_in_reserved(addr), "block_size of address outside of heap");
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
if (_gens[i]->is_in_reserved(addr)) {
|
|
assert(_gens[i]->is_in(addr),
|
|
"addr should be in allocated part of generation");
|
|
return _gens[i]->block_size(addr);
|
|
}
|
|
}
|
|
if (perm_gen()->is_in_reserved(addr)) {
|
|
assert(perm_gen()->is_in(addr),
|
|
"addr should be in allocated part of perm gen");
|
|
return perm_gen()->block_size(addr);
|
|
}
|
|
assert(false, "Some generation should contain the address");
|
|
return 0;
|
|
}
|
|
|
|
bool GenCollectedHeap::block_is_obj(const HeapWord* addr) const {
|
|
assert(is_in_reserved(addr), "block_is_obj of address outside of heap");
|
|
assert(block_start(addr) == addr, "addr must be a block start");
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
if (_gens[i]->is_in_reserved(addr)) {
|
|
return _gens[i]->block_is_obj(addr);
|
|
}
|
|
}
|
|
if (perm_gen()->is_in_reserved(addr)) {
|
|
return perm_gen()->block_is_obj(addr);
|
|
}
|
|
assert(false, "Some generation should contain the address");
|
|
return false;
|
|
}
|
|
|
|
bool GenCollectedHeap::supports_tlab_allocation() const {
|
|
for (int i = 0; i < _n_gens; i += 1) {
|
|
if (_gens[i]->supports_tlab_allocation()) {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
size_t GenCollectedHeap::tlab_capacity(Thread* thr) const {
|
|
size_t result = 0;
|
|
for (int i = 0; i < _n_gens; i += 1) {
|
|
if (_gens[i]->supports_tlab_allocation()) {
|
|
result += _gens[i]->tlab_capacity();
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
size_t GenCollectedHeap::unsafe_max_tlab_alloc(Thread* thr) const {
|
|
size_t result = 0;
|
|
for (int i = 0; i < _n_gens; i += 1) {
|
|
if (_gens[i]->supports_tlab_allocation()) {
|
|
result += _gens[i]->unsafe_max_tlab_alloc();
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
HeapWord* GenCollectedHeap::allocate_new_tlab(size_t size) {
|
|
bool gc_overhead_limit_was_exceeded;
|
|
HeapWord* result = mem_allocate(size /* size */,
|
|
false /* is_large_noref */,
|
|
true /* is_tlab */,
|
|
&gc_overhead_limit_was_exceeded);
|
|
return result;
|
|
}
|
|
|
|
// Requires "*prev_ptr" to be non-NULL. Deletes and a block of minimal size
|
|
// from the list headed by "*prev_ptr".
|
|
static ScratchBlock *removeSmallestScratch(ScratchBlock **prev_ptr) {
|
|
bool first = true;
|
|
size_t min_size = 0; // "first" makes this conceptually infinite.
|
|
ScratchBlock **smallest_ptr, *smallest;
|
|
ScratchBlock *cur = *prev_ptr;
|
|
while (cur) {
|
|
assert(*prev_ptr == cur, "just checking");
|
|
if (first || cur->num_words < min_size) {
|
|
smallest_ptr = prev_ptr;
|
|
smallest = cur;
|
|
min_size = smallest->num_words;
|
|
first = false;
|
|
}
|
|
prev_ptr = &cur->next;
|
|
cur = cur->next;
|
|
}
|
|
smallest = *smallest_ptr;
|
|
*smallest_ptr = smallest->next;
|
|
return smallest;
|
|
}
|
|
|
|
// Sort the scratch block list headed by res into decreasing size order,
|
|
// and set "res" to the result.
|
|
static void sort_scratch_list(ScratchBlock*& list) {
|
|
ScratchBlock* sorted = NULL;
|
|
ScratchBlock* unsorted = list;
|
|
while (unsorted) {
|
|
ScratchBlock *smallest = removeSmallestScratch(&unsorted);
|
|
smallest->next = sorted;
|
|
sorted = smallest;
|
|
}
|
|
list = sorted;
|
|
}
|
|
|
|
ScratchBlock* GenCollectedHeap::gather_scratch(Generation* requestor,
|
|
size_t max_alloc_words) {
|
|
ScratchBlock* res = NULL;
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->contribute_scratch(res, requestor, max_alloc_words);
|
|
}
|
|
sort_scratch_list(res);
|
|
return res;
|
|
}
|
|
|
|
void GenCollectedHeap::release_scratch() {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->reset_scratch();
|
|
}
|
|
}
|
|
|
|
size_t GenCollectedHeap::large_typearray_limit() {
|
|
return gen_policy()->large_typearray_limit();
|
|
}
|
|
|
|
class GenPrepareForVerifyClosure: public GenCollectedHeap::GenClosure {
|
|
void do_generation(Generation* gen) {
|
|
gen->prepare_for_verify();
|
|
}
|
|
};
|
|
|
|
void GenCollectedHeap::prepare_for_verify() {
|
|
ensure_parsability(false); // no need to retire TLABs
|
|
GenPrepareForVerifyClosure blk;
|
|
generation_iterate(&blk, false);
|
|
perm_gen()->prepare_for_verify();
|
|
}
|
|
|
|
|
|
void GenCollectedHeap::generation_iterate(GenClosure* cl,
|
|
bool old_to_young) {
|
|
if (old_to_young) {
|
|
for (int i = _n_gens-1; i >= 0; i--) {
|
|
cl->do_generation(_gens[i]);
|
|
}
|
|
} else {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
cl->do_generation(_gens[i]);
|
|
}
|
|
}
|
|
}
|
|
|
|
void GenCollectedHeap::space_iterate(SpaceClosure* cl) {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->space_iterate(cl, true);
|
|
}
|
|
perm_gen()->space_iterate(cl, true);
|
|
}
|
|
|
|
bool GenCollectedHeap::is_maximal_no_gc() const {
|
|
for (int i = 0; i < _n_gens; i++) { // skip perm gen
|
|
if (!_gens[i]->is_maximal_no_gc()) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void GenCollectedHeap::save_marks() {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->save_marks();
|
|
}
|
|
perm_gen()->save_marks();
|
|
}
|
|
|
|
void GenCollectedHeap::compute_new_generation_sizes(int collectedGen) {
|
|
for (int i = 0; i <= collectedGen; i++) {
|
|
_gens[i]->compute_new_size();
|
|
}
|
|
}
|
|
|
|
GenCollectedHeap* GenCollectedHeap::heap() {
|
|
assert(_gch != NULL, "Uninitialized access to GenCollectedHeap::heap()");
|
|
assert(_gch->kind() == CollectedHeap::GenCollectedHeap, "not a generational heap");
|
|
return _gch;
|
|
}
|
|
|
|
|
|
void GenCollectedHeap::prepare_for_compaction() {
|
|
Generation* scanning_gen = _gens[_n_gens-1];
|
|
// Start by compacting into same gen.
|
|
CompactPoint cp(scanning_gen, NULL, NULL);
|
|
while (scanning_gen != NULL) {
|
|
scanning_gen->prepare_for_compaction(&cp);
|
|
scanning_gen = prev_gen(scanning_gen);
|
|
}
|
|
}
|
|
|
|
GCStats* GenCollectedHeap::gc_stats(int level) const {
|
|
return _gens[level]->gc_stats();
|
|
}
|
|
|
|
void GenCollectedHeap::verify(bool allow_dirty, bool silent, bool option /* ignored */) {
|
|
if (!silent) {
|
|
gclog_or_tty->print("permgen ");
|
|
}
|
|
perm_gen()->verify(allow_dirty);
|
|
for (int i = _n_gens-1; i >= 0; i--) {
|
|
Generation* g = _gens[i];
|
|
if (!silent) {
|
|
gclog_or_tty->print(g->name());
|
|
gclog_or_tty->print(" ");
|
|
}
|
|
g->verify(allow_dirty);
|
|
}
|
|
if (!silent) {
|
|
gclog_or_tty->print("remset ");
|
|
}
|
|
rem_set()->verify();
|
|
if (!silent) {
|
|
gclog_or_tty->print("ref_proc ");
|
|
}
|
|
ReferenceProcessor::verify();
|
|
}
|
|
|
|
void GenCollectedHeap::print() const { print_on(tty); }
|
|
void GenCollectedHeap::print_on(outputStream* st) const {
|
|
for (int i = 0; i < _n_gens; i++) {
|
|
_gens[i]->print_on(st);
|
|
}
|
|
perm_gen()->print_on(st);
|
|
}
|
|
|
|
void GenCollectedHeap::gc_threads_do(ThreadClosure* tc) const {
|
|
if (workers() != NULL) {
|
|
workers()->threads_do(tc);
|
|
}
|
|
#ifndef SERIALGC
|
|
if (UseConcMarkSweepGC) {
|
|
ConcurrentMarkSweepThread::threads_do(tc);
|
|
}
|
|
#endif // SERIALGC
|
|
}
|
|
|
|
void GenCollectedHeap::print_gc_threads_on(outputStream* st) const {
|
|
#ifndef SERIALGC
|
|
if (UseParNewGC) {
|
|
workers()->print_worker_threads_on(st);
|
|
}
|
|
if (UseConcMarkSweepGC) {
|
|
ConcurrentMarkSweepThread::print_all_on(st);
|
|
}
|
|
#endif // SERIALGC
|
|
}
|
|
|
|
void GenCollectedHeap::print_tracing_info() const {
|
|
if (TraceGen0Time) {
|
|
get_gen(0)->print_summary_info();
|
|
}
|
|
if (TraceGen1Time) {
|
|
get_gen(1)->print_summary_info();
|
|
}
|
|
}
|
|
|
|
void GenCollectedHeap::print_heap_change(size_t prev_used) const {
|
|
if (PrintGCDetails && Verbose) {
|
|
gclog_or_tty->print(" " SIZE_FORMAT
|
|
"->" SIZE_FORMAT
|
|
"(" SIZE_FORMAT ")",
|
|
prev_used, used(), capacity());
|
|
} else {
|
|
gclog_or_tty->print(" " SIZE_FORMAT "K"
|
|
"->" SIZE_FORMAT "K"
|
|
"(" SIZE_FORMAT "K)",
|
|
prev_used / K, used() / K, capacity() / K);
|
|
}
|
|
}
|
|
|
|
//New method to print perm gen info with PrintGCDetails flag
|
|
void GenCollectedHeap::print_perm_heap_change(size_t perm_prev_used) const {
|
|
gclog_or_tty->print(", [%s :", perm_gen()->short_name());
|
|
perm_gen()->print_heap_change(perm_prev_used);
|
|
gclog_or_tty->print("]");
|
|
}
|
|
|
|
class GenGCPrologueClosure: public GenCollectedHeap::GenClosure {
|
|
private:
|
|
bool _full;
|
|
public:
|
|
void do_generation(Generation* gen) {
|
|
gen->gc_prologue(_full);
|
|
}
|
|
GenGCPrologueClosure(bool full) : _full(full) {};
|
|
};
|
|
|
|
void GenCollectedHeap::gc_prologue(bool full) {
|
|
assert(InlineCacheBuffer::is_empty(), "should have cleaned up ICBuffer");
|
|
|
|
always_do_update_barrier = false;
|
|
// Fill TLAB's and such
|
|
CollectedHeap::accumulate_statistics_all_tlabs();
|
|
ensure_parsability(true); // retire TLABs
|
|
|
|
// Call allocation profiler
|
|
AllocationProfiler::iterate_since_last_gc();
|
|
// Walk generations
|
|
GenGCPrologueClosure blk(full);
|
|
generation_iterate(&blk, false); // not old-to-young.
|
|
perm_gen()->gc_prologue(full);
|
|
};
|
|
|
|
class GenGCEpilogueClosure: public GenCollectedHeap::GenClosure {
|
|
private:
|
|
bool _full;
|
|
public:
|
|
void do_generation(Generation* gen) {
|
|
gen->gc_epilogue(_full);
|
|
}
|
|
GenGCEpilogueClosure(bool full) : _full(full) {};
|
|
};
|
|
|
|
void GenCollectedHeap::gc_epilogue(bool full) {
|
|
// Remember if a partial collection of the heap failed, and
|
|
// we did a complete collection.
|
|
if (full && incremental_collection_will_fail()) {
|
|
set_last_incremental_collection_failed();
|
|
} else {
|
|
clear_last_incremental_collection_failed();
|
|
}
|
|
// Clear the flag, if set; the generation gc_epilogues will set the
|
|
// flag again if the condition persists despite the collection.
|
|
clear_incremental_collection_will_fail();
|
|
|
|
#ifdef COMPILER2
|
|
assert(DerivedPointerTable::is_empty(), "derived pointer present");
|
|
size_t actual_gap = pointer_delta((HeapWord*) (max_uintx-3), *(end_addr()));
|
|
guarantee(actual_gap > (size_t)FastAllocateSizeLimit, "inline allocation wraps");
|
|
#endif /* COMPILER2 */
|
|
|
|
resize_all_tlabs();
|
|
|
|
GenGCEpilogueClosure blk(full);
|
|
generation_iterate(&blk, false); // not old-to-young.
|
|
perm_gen()->gc_epilogue(full);
|
|
|
|
always_do_update_barrier = UseConcMarkSweepGC;
|
|
};
|
|
|
|
#ifndef PRODUCT
|
|
class GenGCSaveTopsBeforeGCClosure: public GenCollectedHeap::GenClosure {
|
|
private:
|
|
public:
|
|
void do_generation(Generation* gen) {
|
|
gen->record_spaces_top();
|
|
}
|
|
};
|
|
|
|
void GenCollectedHeap::record_gen_tops_before_GC() {
|
|
if (ZapUnusedHeapArea) {
|
|
GenGCSaveTopsBeforeGCClosure blk;
|
|
generation_iterate(&blk, false); // not old-to-young.
|
|
perm_gen()->record_spaces_top();
|
|
}
|
|
}
|
|
#endif // not PRODUCT
|
|
|
|
class GenEnsureParsabilityClosure: public GenCollectedHeap::GenClosure {
|
|
public:
|
|
void do_generation(Generation* gen) {
|
|
gen->ensure_parsability();
|
|
}
|
|
};
|
|
|
|
void GenCollectedHeap::ensure_parsability(bool retire_tlabs) {
|
|
CollectedHeap::ensure_parsability(retire_tlabs);
|
|
GenEnsureParsabilityClosure ep_cl;
|
|
generation_iterate(&ep_cl, false);
|
|
perm_gen()->ensure_parsability();
|
|
}
|
|
|
|
oop GenCollectedHeap::handle_failed_promotion(Generation* gen,
|
|
oop obj,
|
|
size_t obj_size) {
|
|
assert(obj_size == (size_t)obj->size(), "bad obj_size passed in");
|
|
HeapWord* result = NULL;
|
|
|
|
// First give each higher generation a chance to allocate the promoted object.
|
|
Generation* allocator = next_gen(gen);
|
|
if (allocator != NULL) {
|
|
do {
|
|
result = allocator->allocate(obj_size, false);
|
|
} while (result == NULL && (allocator = next_gen(allocator)) != NULL);
|
|
}
|
|
|
|
if (result == NULL) {
|
|
// Then give gen and higher generations a chance to expand and allocate the
|
|
// object.
|
|
do {
|
|
result = gen->expand_and_allocate(obj_size, false);
|
|
} while (result == NULL && (gen = next_gen(gen)) != NULL);
|
|
}
|
|
|
|
if (result != NULL) {
|
|
Copy::aligned_disjoint_words((HeapWord*)obj, result, obj_size);
|
|
}
|
|
return oop(result);
|
|
}
|
|
|
|
class GenTimeOfLastGCClosure: public GenCollectedHeap::GenClosure {
|
|
jlong _time; // in ms
|
|
jlong _now; // in ms
|
|
|
|
public:
|
|
GenTimeOfLastGCClosure(jlong now) : _time(now), _now(now) { }
|
|
|
|
jlong time() { return _time; }
|
|
|
|
void do_generation(Generation* gen) {
|
|
_time = MIN2(_time, gen->time_of_last_gc(_now));
|
|
}
|
|
};
|
|
|
|
jlong GenCollectedHeap::millis_since_last_gc() {
|
|
jlong now = os::javaTimeMillis();
|
|
GenTimeOfLastGCClosure tolgc_cl(now);
|
|
// iterate over generations getting the oldest
|
|
// time that a generation was collected
|
|
generation_iterate(&tolgc_cl, false);
|
|
tolgc_cl.do_generation(perm_gen());
|
|
// XXX Despite the assert above, since javaTimeMillis()
|
|
// doesnot guarantee monotonically increasing return
|
|
// values (note, i didn't say "strictly monotonic"),
|
|
// we need to guard against getting back a time
|
|
// later than now. This should be fixed by basing
|
|
// on someting like gethrtime() which guarantees
|
|
// monotonicity. Note that cond_wait() is susceptible
|
|
// to a similar problem, because its interface is
|
|
// based on absolute time in the form of the
|
|
// system time's notion of UCT. See also 4506635
|
|
// for yet another problem of similar nature. XXX
|
|
jlong retVal = now - tolgc_cl.time();
|
|
if (retVal < 0) {
|
|
NOT_PRODUCT(warning("time warp: %d", retVal);)
|
|
return 0;
|
|
}
|
|
return retVal;
|
|
}
|