| /* |
| * Copyright (c) 2014, 2019, 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 "jfr/leakprofiler/chains/bitset.hpp" |
| #include "jfr/leakprofiler/chains/bfsClosure.hpp" |
| #include "jfr/leakprofiler/chains/dfsClosure.hpp" |
| #include "jfr/leakprofiler/chains/edge.hpp" |
| #include "jfr/leakprofiler/chains/edgeStore.hpp" |
| #include "jfr/leakprofiler/chains/edgeQueue.hpp" |
| #include "jfr/leakprofiler/utilities/granularTimer.hpp" |
| #include "jfr/leakprofiler/utilities/unifiedOop.hpp" |
| #include "logging/log.hpp" |
| #include "memory/iterator.inline.hpp" |
| #include "memory/resourceArea.hpp" |
| #include "oops/access.inline.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "utilities/align.hpp" |
| |
| BFSClosure::BFSClosure(EdgeQueue* edge_queue, EdgeStore* edge_store, BitSet* mark_bits) : |
| _edge_queue(edge_queue), |
| _edge_store(edge_store), |
| _mark_bits(mark_bits), |
| _current_parent(NULL), |
| _current_frontier_level(0), |
| _next_frontier_idx(0), |
| _prev_frontier_idx(0), |
| _dfs_fallback_idx(0), |
| _use_dfs(false) { |
| } |
| |
| static void log_frontier_level_summary(size_t level, |
| size_t high_idx, |
| size_t low_idx, |
| size_t edge_size) { |
| const size_t nof_edges_in_frontier = high_idx - low_idx; |
| log_trace(jfr, system)( |
| "BFS front: " SIZE_FORMAT " edges: " SIZE_FORMAT " size: " SIZE_FORMAT " [KB]", |
| level, |
| nof_edges_in_frontier, |
| (nof_edges_in_frontier * edge_size) / K |
| ); |
| } |
| |
| void BFSClosure::log_completed_frontier() const { |
| log_frontier_level_summary(_current_frontier_level, |
| _next_frontier_idx, |
| _prev_frontier_idx, |
| _edge_queue->sizeof_edge()); |
| } |
| |
| void BFSClosure::log_dfs_fallback() const { |
| const size_t edge_size = _edge_queue->sizeof_edge(); |
| // first complete summary for frontier in progress |
| log_frontier_level_summary(_current_frontier_level, |
| _next_frontier_idx, |
| _prev_frontier_idx, |
| edge_size); |
| |
| // and then also complete the last frontier |
| log_frontier_level_summary(_current_frontier_level + 1, |
| _edge_queue->bottom(), |
| _next_frontier_idx, |
| edge_size); |
| |
| // additional information about DFS fallover |
| log_trace(jfr, system)( |
| "BFS front: " SIZE_FORMAT " filled edge queue at edge: " SIZE_FORMAT, |
| _current_frontier_level, |
| _dfs_fallback_idx |
| ); |
| |
| const size_t nof_dfs_completed_edges = _edge_queue->bottom() - _dfs_fallback_idx; |
| log_trace(jfr, system)( |
| "DFS to complete " SIZE_FORMAT " edges size: " SIZE_FORMAT " [KB]", |
| nof_dfs_completed_edges, |
| (nof_dfs_completed_edges * edge_size) / K |
| ); |
| } |
| |
| void BFSClosure::process() { |
| process_root_set(); |
| process_queue(); |
| } |
| |
| void BFSClosure::process_root_set() { |
| for (size_t idx = _edge_queue->bottom(); idx < _edge_queue->top(); ++idx) { |
| const Edge* edge = _edge_queue->element_at(idx); |
| assert(edge->parent() == NULL, "invariant"); |
| process(edge->reference(), edge->pointee()); |
| } |
| } |
| |
| void BFSClosure::process(const oop* reference, const oop pointee) { |
| closure_impl(reference, pointee); |
| } |
| void BFSClosure::closure_impl(const oop* reference, const oop pointee) { |
| assert(reference != NULL, "invariant"); |
| assert(UnifiedOop::dereference(reference) == pointee, "invariant"); |
| |
| if (GranularTimer::is_finished()) { |
| return; |
| } |
| |
| if (_use_dfs) { |
| assert(_current_parent != NULL, "invariant"); |
| DFSClosure::find_leaks_from_edge(_edge_store, _mark_bits, _current_parent); |
| return; |
| } |
| |
| if (!_mark_bits->is_marked(pointee)) { |
| _mark_bits->mark_obj(pointee); |
| // is the pointee a sample object? |
| if (NULL == pointee->mark().to_pointer()) { |
| add_chain(reference, pointee); |
| } |
| |
| // if we are processinig initial root set, don't add to queue |
| if (_current_parent != NULL) { |
| _edge_queue->add(_current_parent, reference); |
| } |
| |
| if (_edge_queue->is_full()) { |
| dfs_fallback(); |
| } |
| } |
| } |
| |
| void BFSClosure::add_chain(const oop* reference, const oop pointee) { |
| assert(pointee != NULL, "invariant"); |
| assert(NULL == pointee->mark(), "invariant"); |
| Edge leak_edge(_current_parent, reference); |
| _edge_store->put_chain(&leak_edge, _current_parent == NULL ? 1 : _current_frontier_level + 2); |
| } |
| |
| void BFSClosure::dfs_fallback() { |
| assert(_edge_queue->is_full(), "invariant"); |
| _use_dfs = true; |
| _dfs_fallback_idx = _edge_queue->bottom(); |
| while (!_edge_queue->is_empty()) { |
| const Edge* edge = _edge_queue->remove(); |
| if (edge->pointee() != NULL) { |
| DFSClosure::find_leaks_from_edge(_edge_store, _mark_bits, edge); |
| } |
| } |
| } |
| |
| void BFSClosure::process_queue() { |
| assert(_current_frontier_level == 0, "invariant"); |
| assert(_next_frontier_idx == 0, "invariant"); |
| assert(_prev_frontier_idx == 0, "invariant"); |
| |
| _next_frontier_idx = _edge_queue->top(); |
| while (!is_complete()) { |
| iterate(_edge_queue->remove()); // edge_queue.remove() increments bottom |
| } |
| } |
| |
| void BFSClosure::step_frontier() const { |
| log_completed_frontier(); |
| ++_current_frontier_level; |
| _prev_frontier_idx = _next_frontier_idx; |
| _next_frontier_idx = _edge_queue->top(); |
| } |
| |
| bool BFSClosure::is_complete() const { |
| if (_edge_queue->bottom() < _next_frontier_idx) { |
| return false; |
| } |
| if (_edge_queue->bottom() > _next_frontier_idx) { |
| // fallback onto DFS as part of processing the frontier |
| assert(_dfs_fallback_idx >= _prev_frontier_idx, "invariant"); |
| assert(_dfs_fallback_idx < _next_frontier_idx, "invariant"); |
| log_dfs_fallback(); |
| return true; |
| } |
| assert(_edge_queue->bottom() == _next_frontier_idx, "invariant"); |
| if (_edge_queue->is_empty()) { |
| return true; |
| } |
| step_frontier(); |
| return false; |
| } |
| |
| void BFSClosure::iterate(const Edge* parent) { |
| assert(parent != NULL, "invariant"); |
| const oop pointee = parent->pointee(); |
| assert(pointee != NULL, "invariant"); |
| _current_parent = parent; |
| pointee->oop_iterate(this); |
| } |
| |
| void BFSClosure::do_oop(oop* ref) { |
| assert(ref != NULL, "invariant"); |
| assert(is_aligned(ref, HeapWordSize), "invariant"); |
| const oop pointee = *ref; |
| if (pointee != NULL) { |
| closure_impl(ref, pointee); |
| } |
| } |
| |
| void BFSClosure::do_oop(narrowOop* ref) { |
| assert(ref != NULL, "invariant"); |
| assert(is_aligned(ref, sizeof(narrowOop)), "invariant"); |
| const oop pointee = RawAccess<>::oop_load(ref); |
| if (pointee != NULL) { |
| closure_impl(UnifiedOop::encode(ref), pointee); |
| } |
| } |
| |
| void BFSClosure::do_root(const oop* ref) { |
| assert(ref != NULL, "invariant"); |
| if (!_edge_queue->is_full()) { |
| _edge_queue->add(NULL, ref); |
| } |
| } |