Mercurial > hg > graal-jvmci-8
diff src/share/vm/gc_implementation/g1/g1Allocator.cpp @ 20404:227a9e5e4b4a
8057536: Refactor G1 to allow context specific allocations
Summary: Splitting out a g1 allocator class to simply specialized allocators which can associate each allocation with a given context.
Reviewed-by: mgerdin, brutisso
author | sjohanss |
---|---|
date | Fri, 05 Sep 2014 09:49:19 +0200 |
parents | |
children | 80ac3ee51955 |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/gc_implementation/g1/g1Allocator.cpp Fri Sep 05 09:49:19 2014 +0200 @@ -0,0 +1,155 @@ +/* + * Copyright (c) 2014, 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. + * + */ + +#include "precompiled.hpp" +#include "gc_implementation/g1/g1Allocator.hpp" +#include "gc_implementation/g1/g1CollectedHeap.hpp" +#include "gc_implementation/g1/g1CollectorPolicy.hpp" +#include "gc_implementation/g1/heapRegion.inline.hpp" +#include "gc_implementation/g1/heapRegionSet.inline.hpp" + +void G1DefaultAllocator::init_mutator_alloc_region() { + assert(_mutator_alloc_region.get() == NULL, "pre-condition"); + _mutator_alloc_region.init(); +} + +void G1DefaultAllocator::release_mutator_alloc_region() { + _mutator_alloc_region.release(); + assert(_mutator_alloc_region.get() == NULL, "post-condition"); +} + +void G1Allocator::reuse_retained_old_region(EvacuationInfo& evacuation_info, + OldGCAllocRegion* old, + HeapRegion** retained_old) { + HeapRegion* retained_region = *retained_old; + *retained_old = NULL; + + // We will discard the current GC alloc region if: + // a) it's in the collection set (it can happen!), + // b) it's already full (no point in using it), + // c) it's empty (this means that it was emptied during + // a cleanup and it should be on the free list now), or + // d) it's humongous (this means that it was emptied + // during a cleanup and was added to the free list, but + // has been subsequently used to allocate a humongous + // object that may be less than the region size). + if (retained_region != NULL && + !retained_region->in_collection_set() && + !(retained_region->top() == retained_region->end()) && + !retained_region->is_empty() && + !retained_region->isHumongous()) { + retained_region->record_top_and_timestamp(); + // The retained region was added to the old region set when it was + // retired. We have to remove it now, since we don't allow regions + // we allocate to in the region sets. We'll re-add it later, when + // it's retired again. + _g1h->_old_set.remove(retained_region); + bool during_im = _g1h->g1_policy()->during_initial_mark_pause(); + retained_region->note_start_of_copying(during_im); + old->set(retained_region); + _g1h->_hr_printer.reuse(retained_region); + evacuation_info.set_alloc_regions_used_before(retained_region->used()); + } +} + +void G1DefaultAllocator::init_gc_alloc_regions(EvacuationInfo& evacuation_info) { + assert_at_safepoint(true /* should_be_vm_thread */); + + _survivor_gc_alloc_region.init(); + _old_gc_alloc_region.init(); + reuse_retained_old_region(evacuation_info, + &_old_gc_alloc_region, + &_retained_old_gc_alloc_region); +} + +void G1DefaultAllocator::release_gc_alloc_regions(uint no_of_gc_workers, EvacuationInfo& evacuation_info) { + AllocationContext_t context = AllocationContext::current(); + evacuation_info.set_allocation_regions(survivor_gc_alloc_region(context)->count() + + old_gc_alloc_region(context)->count()); + survivor_gc_alloc_region(context)->release(); + // If we have an old GC alloc region to release, we'll save it in + // _retained_old_gc_alloc_region. If we don't + // _retained_old_gc_alloc_region will become NULL. This is what we + // want either way so no reason to check explicitly for either + // condition. + _retained_old_gc_alloc_region = old_gc_alloc_region(context)->release(); + + if (ResizePLAB) { + _g1h->_survivor_plab_stats.adjust_desired_plab_sz(no_of_gc_workers); + _g1h->_old_plab_stats.adjust_desired_plab_sz(no_of_gc_workers); + } +} + +void G1DefaultAllocator::abandon_gc_alloc_regions() { + assert(survivor_gc_alloc_region(AllocationContext::current())->get() == NULL, "pre-condition"); + assert(old_gc_alloc_region(AllocationContext::current())->get() == NULL, "pre-condition"); + _retained_old_gc_alloc_region = NULL; +} + +G1ParGCAllocBuffer::G1ParGCAllocBuffer(size_t gclab_word_size) : + ParGCAllocBuffer(gclab_word_size), _retired(true) { } + +HeapWord* G1ParGCAllocator::allocate_slow(GCAllocPurpose purpose, size_t word_sz, AllocationContext_t context) { + HeapWord* obj = NULL; + size_t gclab_word_size = _g1h->desired_plab_sz(purpose); + if (word_sz * 100 < gclab_word_size * ParallelGCBufferWastePct) { + G1ParGCAllocBuffer* alloc_buf = alloc_buffer(purpose, context); + add_to_alloc_buffer_waste(alloc_buf->words_remaining()); + alloc_buf->retire(false /* end_of_gc */, false /* retain */); + + HeapWord* buf = _g1h->par_allocate_during_gc(purpose, gclab_word_size, context); + if (buf == NULL) { + return NULL; // Let caller handle allocation failure. + } + // Otherwise. + alloc_buf->set_word_size(gclab_word_size); + alloc_buf->set_buf(buf); + + obj = alloc_buf->allocate(word_sz); + assert(obj != NULL, "buffer was definitely big enough..."); + } else { + obj = _g1h->par_allocate_during_gc(purpose, word_sz, context); + } + return obj; +} + +G1DefaultParGCAllocator::G1DefaultParGCAllocator(G1CollectedHeap* g1h) : + G1ParGCAllocator(g1h), + _surviving_alloc_buffer(g1h->desired_plab_sz(GCAllocForSurvived)), + _tenured_alloc_buffer(g1h->desired_plab_sz(GCAllocForTenured)) { + + _alloc_buffers[GCAllocForSurvived] = &_surviving_alloc_buffer; + _alloc_buffers[GCAllocForTenured] = &_tenured_alloc_buffer; + +} + +void G1DefaultParGCAllocator::retire_alloc_buffers() { + for (int ap = 0; ap < GCAllocPurposeCount; ++ap) { + size_t waste = _alloc_buffers[ap]->words_remaining(); + add_to_alloc_buffer_waste(waste); + _alloc_buffers[ap]->flush_stats_and_retire(_g1h->stats_for_purpose((GCAllocPurpose)ap), + true /* end_of_gc */, + false /* retain */); + } +}