Mercurial > hg > truffle
view src/share/vm/gc_implementation/g1/heapRegionSeq.cpp @ 9099:ed81c74f92ff
Cache boolean flags instead of full Annotation objects
author | Christian Wimmer <christian.wimmer@oracle.com> |
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date | Fri, 12 Apr 2013 16:05:56 -0700 |
parents | d2a62e0f25eb |
children | b0d20fa374b4 |
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/* * Copyright (c) 2001, 2012, 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/heapRegion.hpp" #include "gc_implementation/g1/heapRegionSeq.inline.hpp" #include "gc_implementation/g1/heapRegionSets.hpp" #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" #include "memory/allocation.hpp" // Private uint HeapRegionSeq::find_contiguous_from(uint from, uint num) { uint len = length(); assert(num > 1, "use this only for sequences of length 2 or greater"); assert(from <= len, err_msg("from: %u should be valid and <= than %u", from, len)); uint curr = from; uint first = G1_NULL_HRS_INDEX; uint num_so_far = 0; while (curr < len && num_so_far < num) { if (at(curr)->is_empty()) { if (first == G1_NULL_HRS_INDEX) { first = curr; num_so_far = 1; } else { num_so_far += 1; } } else { first = G1_NULL_HRS_INDEX; num_so_far = 0; } curr += 1; } assert(num_so_far <= num, "post-condition"); if (num_so_far == num) { // we found enough space for the humongous object assert(from <= first && first < len, "post-condition"); assert(first < curr && (curr - first) == num, "post-condition"); for (uint i = first; i < first + num; ++i) { assert(at(i)->is_empty(), "post-condition"); } return first; } else { // we failed to find enough space for the humongous object return G1_NULL_HRS_INDEX; } } // Public void HeapRegionSeq::initialize(HeapWord* bottom, HeapWord* end, uint max_length) { assert((uintptr_t) bottom % HeapRegion::GrainBytes == 0, "bottom should be heap region aligned"); assert((uintptr_t) end % HeapRegion::GrainBytes == 0, "end should be heap region aligned"); _length = 0; _heap_bottom = bottom; _heap_end = end; _region_shift = HeapRegion::LogOfHRGrainBytes; _next_search_index = 0; _allocated_length = 0; _max_length = max_length; _regions = NEW_C_HEAP_ARRAY(HeapRegion*, max_length, mtGC); memset(_regions, 0, (size_t) max_length * sizeof(HeapRegion*)); _regions_biased = _regions - ((uintx) bottom >> _region_shift); assert(&_regions[0] == &_regions_biased[addr_to_index_biased(bottom)], "bottom should be included in the region with index 0"); } MemRegion HeapRegionSeq::expand_by(HeapWord* old_end, HeapWord* new_end, FreeRegionList* list) { assert(old_end < new_end, "don't call it otherwise"); G1CollectedHeap* g1h = G1CollectedHeap::heap(); HeapWord* next_bottom = old_end; assert(_heap_bottom <= next_bottom, "invariant"); while (next_bottom < new_end) { assert(next_bottom < _heap_end, "invariant"); uint index = length(); assert(index < _max_length, "otherwise we cannot expand further"); if (index == 0) { // We have not allocated any regions so far assert(next_bottom == _heap_bottom, "invariant"); } else { // next_bottom should match the end of the last/previous region assert(next_bottom == at(index - 1)->end(), "invariant"); } if (index == _allocated_length) { // We have to allocate a new HeapRegion. HeapRegion* new_hr = g1h->new_heap_region(index, next_bottom); if (new_hr == NULL) { // allocation failed, we bail out and return what we have done so far return MemRegion(old_end, next_bottom); } assert(_regions[index] == NULL, "invariant"); _regions[index] = new_hr; increment_length(&_allocated_length); } // Have to increment the length first, otherwise we will get an // assert failure at(index) below. increment_length(&_length); HeapRegion* hr = at(index); list->add_as_tail(hr); next_bottom = hr->end(); } assert(next_bottom == new_end, "post-condition"); return MemRegion(old_end, next_bottom); } uint HeapRegionSeq::free_suffix() { uint res = 0; uint index = length(); while (index > 0) { index -= 1; if (!at(index)->is_empty()) { break; } res += 1; } return res; } uint HeapRegionSeq::find_contiguous(uint num) { assert(num > 1, "use this only for sequences of length 2 or greater"); assert(_next_search_index <= length(), err_msg("_next_search_index: %u should be valid and <= than %u", _next_search_index, length())); uint start = _next_search_index; uint res = find_contiguous_from(start, num); if (res == G1_NULL_HRS_INDEX && start > 0) { // Try starting from the beginning. If _next_search_index was 0, // no point in doing this again. res = find_contiguous_from(0, num); } if (res != G1_NULL_HRS_INDEX) { assert(res < length(), err_msg("res: %u should be valid", res)); _next_search_index = res + num; assert(_next_search_index <= length(), err_msg("_next_search_index: %u should be valid and <= than %u", _next_search_index, length())); } return res; } void HeapRegionSeq::iterate(HeapRegionClosure* blk) const { iterate_from((HeapRegion*) NULL, blk); } void HeapRegionSeq::iterate_from(HeapRegion* hr, HeapRegionClosure* blk) const { uint hr_index = 0; if (hr != NULL) { hr_index = hr->hrs_index(); } uint len = length(); for (uint i = hr_index; i < len; i += 1) { bool res = blk->doHeapRegion(at(i)); if (res) { blk->incomplete(); return; } } for (uint i = 0; i < hr_index; i += 1) { bool res = blk->doHeapRegion(at(i)); if (res) { blk->incomplete(); return; } } } MemRegion HeapRegionSeq::shrink_by(size_t shrink_bytes, uint* num_regions_deleted) { // Reset this in case it's currently pointing into the regions that // we just removed. _next_search_index = 0; assert(shrink_bytes % os::vm_page_size() == 0, "unaligned"); assert(shrink_bytes % HeapRegion::GrainBytes == 0, "unaligned"); assert(length() > 0, "the region sequence should not be empty"); assert(length() <= _allocated_length, "invariant"); assert(_allocated_length > 0, "we should have at least one region committed"); // around the loop, i will be the next region to be removed uint i = length() - 1; assert(i > 0, "we should never remove all regions"); // [last_start, end) is the MemRegion that covers the regions we will remove. HeapWord* end = at(i)->end(); HeapWord* last_start = end; *num_regions_deleted = 0; while (shrink_bytes > 0) { HeapRegion* cur = at(i); // We should leave the humongous regions where they are. if (cur->isHumongous()) break; // We should stop shrinking if we come across a non-empty region. if (!cur->is_empty()) break; i -= 1; *num_regions_deleted += 1; shrink_bytes -= cur->capacity(); last_start = cur->bottom(); decrement_length(&_length); // We will reclaim the HeapRegion. _allocated_length should be // covering this index. So, even though we removed the region from // the active set by decreasing _length, we still have it // available in the future if we need to re-use it. assert(i > 0, "we should never remove all regions"); assert(length() > 0, "we should never remove all regions"); } return MemRegion(last_start, end); } #ifndef PRODUCT void HeapRegionSeq::verify_optional() { guarantee(_length <= _allocated_length, err_msg("invariant: _length: %u _allocated_length: %u", _length, _allocated_length)); guarantee(_allocated_length <= _max_length, err_msg("invariant: _allocated_length: %u _max_length: %u", _allocated_length, _max_length)); guarantee(_next_search_index <= _length, err_msg("invariant: _next_search_index: %u _length: %u", _next_search_index, _length)); HeapWord* prev_end = _heap_bottom; for (uint i = 0; i < _allocated_length; i += 1) { HeapRegion* hr = _regions[i]; guarantee(hr != NULL, err_msg("invariant: i: %u", i)); guarantee(hr->bottom() == prev_end, err_msg("invariant i: %u "HR_FORMAT" prev_end: "PTR_FORMAT, i, HR_FORMAT_PARAMS(hr), prev_end)); guarantee(hr->hrs_index() == i, err_msg("invariant: i: %u hrs_index(): %u", i, hr->hrs_index())); if (i < _length) { // Asserts will fire if i is >= _length HeapWord* addr = hr->bottom(); guarantee(addr_to_region(addr) == hr, "sanity"); guarantee(addr_to_region_unsafe(addr) == hr, "sanity"); } else { guarantee(hr->is_empty(), "sanity"); guarantee(!hr->isHumongous(), "sanity"); // using assert instead of guarantee here since containing_set() // is only available in non-product builds. assert(hr->containing_set() == NULL, "sanity"); } if (hr->startsHumongous()) { prev_end = hr->orig_end(); } else { prev_end = hr->end(); } } for (uint i = _allocated_length; i < _max_length; i += 1) { guarantee(_regions[i] == NULL, err_msg("invariant i: %u", i)); } } #endif // PRODUCT