--- /dev/null 2019-01-28 17:46:09.000000000 +0800 +++ new/src/share/vm/jfr/leakprofiler/emitEventOperation.cpp 2019-01-28 17:46:09.000000000 +0800 @@ -0,0 +1,233 @@ +/* + * 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 "gc_interface/collectedHeap.hpp" +#include "jfr/leakprofiler/utilities/granularTimer.hpp" +#include "jfr/leakprofiler/chains/rootSetClosure.hpp" +#include "jfr/leakprofiler/chains/edge.hpp" +#include "jfr/leakprofiler/chains/edgeQueue.hpp" +#include "jfr/leakprofiler/chains/edgeStore.hpp" +#include "jfr/leakprofiler/chains/bitset.hpp" +#include "jfr/leakprofiler/sampling/objectSample.hpp" +#include "jfr/leakprofiler/leakProfiler.hpp" +#include "jfr/leakprofiler/checkpoint/objectSampleCheckpoint.hpp" +#include "jfr/leakprofiler/sampling/objectSampler.hpp" +#include "jfr/leakprofiler/emitEventOperation.hpp" +#include "jfr/leakprofiler/chains/bfsClosure.hpp" +#include "jfr/leakprofiler/chains/dfsClosure.hpp" +#include "jfr/leakprofiler/chains/objectSampleMarker.hpp" +#include "jfr/recorder/access/jfrbackend.hpp" +#include "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp" +//#include "logging/log.hpp" +#include "memory/resourceArea.hpp" +#include "memory/universe.hpp" +#include "oops/markOop.hpp" +#include "oops/oop.inline.hpp" +#include "runtime/safepoint.hpp" +#include "runtime/vmThread.hpp" +#include "trace/tracing.hpp" +#include "utilities/globalDefinitions.hpp" + +/* The EdgeQueue is backed by directly managed virtual memory. + * We will attempt to dimension an initial reservation + * in proportion to the size of the heap (represented by heap_region). + * Initial memory reservation: 5% of the heap OR at least 32 Mb + * Commit ratio: 1 : 10 (subject to allocation granularties) + */ +static size_t edge_queue_memory_reservation(const MemRegion& heap_region) { + const size_t memory_reservation_bytes = MAX2(heap_region.byte_size() / 20, 32*M); + assert(memory_reservation_bytes >= (size_t)32*M, "invariant"); + return memory_reservation_bytes; +} + +static size_t edge_queue_memory_commit_size(size_t memory_reservation_bytes) { + const size_t memory_commit_block_size_bytes = memory_reservation_bytes / 10; + assert(memory_commit_block_size_bytes >= (size_t)3*M, "invariant"); + return memory_commit_block_size_bytes; +} + +static void log_edge_queue_summary(const EdgeQueue& edge_queue) { + log_trace(jfr, system)("EdgeQueue reserved size total: " SIZE_FORMAT " [KB]", edge_queue.reserved_size() / K); + log_trace(jfr, system)("EdgeQueue edges total: " SIZE_FORMAT, edge_queue.top()); + log_trace(jfr, system)("EdgeQueue liveset total: " SIZE_FORMAT " [KB]", edge_queue.live_set() / K); + if (edge_queue.reserved_size() > 0) { + log_trace(jfr, system)("EdgeQueue commit reserve ratio: %f\n", + ((double)edge_queue.live_set() / (double)edge_queue.reserved_size())); + } +} + +void EmitEventOperation::doit() { + assert(LeakProfiler::is_running(), "invariant"); + _object_sampler = LeakProfiler::object_sampler(); + assert(_object_sampler != NULL, "invariant"); + + _vm_thread = VMThread::vm_thread(); + assert(_vm_thread == Thread::current(), "invariant"); + _vm_thread_data = _vm_thread->trace_data(); + assert(_vm_thread_data != NULL, "invariant"); + assert(_vm_thread->trace_data()->thread_id() == THREAD_TRACE_ID(_vm_thread), "invariant"); + + // The VM_Operation::evaluate() which invoked doit() + // contains a top level ResourceMark + + // save the original markWord for the potential leak objects + // to be restored on function exit + ObjectSampleMarker marker; + if (ObjectSampleCheckpoint::mark(marker, _emit_all) == 0) { + return; + } + + EdgeStore edge_store; + + GranularTimer::start(_cutoff_ticks, 1000000); + if (_cutoff_ticks <= 0) { + // no chains + write_events(&edge_store); + return; + } + + assert(_cutoff_ticks > 0, "invariant"); + + // The bitset used for marking is dimensioned as a function of the heap size + const MemRegion heap_region = Universe::heap()->reserved_region(); + BitSet mark_bits(heap_region); + + // The edge queue is dimensioned as a fraction of the heap size + const size_t edge_queue_reservation_size = edge_queue_memory_reservation(heap_region); + EdgeQueue edge_queue(edge_queue_reservation_size, edge_queue_memory_commit_size(edge_queue_reservation_size)); + + // The initialize() routines will attempt to reserve and allocate backing storage memory. + // Failure to accommodate will render root chain processing impossible. + // As a fallback on failure, just write out the existing samples, flat, without chains. + if (!(mark_bits.initialize() && edge_queue.initialize())) { + log_warning(jfr)("Unable to allocate memory for root chain processing"); + write_events(&edge_store); + return; + } + + // necessary condition for attempting a root set iteration + Universe::heap()->ensure_parsability(false); + + RootSetClosure::add_to_queue(&edge_queue); + if (edge_queue.is_full()) { + // Pathological case where roots don't fit in queue + // Do a depth-first search, but mark roots first + // to avoid walking sideways over roots + DFSClosure::find_leaks_from_root_set(&edge_store, &mark_bits); + } else { + BFSClosure bfs(&edge_queue, &edge_store, &mark_bits); + bfs.process(); + } + GranularTimer::stop(); + write_events(&edge_store); + log_edge_queue_summary(edge_queue); +} + +int EmitEventOperation::write_events(EdgeStore* edge_store) { + assert(_object_sampler != NULL, "invariant"); + assert(edge_store != NULL, "invariant"); + assert(_vm_thread != NULL, "invariant"); + assert(_vm_thread_data != NULL, "invariant"); + assert(SafepointSynchronize::is_at_safepoint(), "invariant"); + + // save thread id in preparation for thread local trace data manipulations + const traceid vmthread_id = _vm_thread_data->thread_id(); + assert(_vm_thread_data->thread_id() == THREAD_TRACE_ID(_vm_thread), "invariant"); + + const jlong last_sweep = _emit_all ? max_jlong : _object_sampler->last_sweep().value(); + int count = 0; + + for (int i = 0; i < _object_sampler->item_count(); ++i) { + const ObjectSample* sample = _object_sampler->item_at(i); + if (sample->is_alive_and_older_than(last_sweep)) { + write_event(sample, edge_store); + ++count; + } + } + + // restore thread local stack trace and thread id + _vm_thread_data->set_thread_id(vmthread_id); + _vm_thread_data->clear_cached_stack_trace(); + assert(_vm_thread_data->thread_id() == THREAD_TRACE_ID(_vm_thread), "invariant"); + + if (count > 0) { + // serialize assoicated checkpoints + ObjectSampleCheckpoint::write(edge_store, _emit_all, _vm_thread); + } + return count; +} + +static int array_size(const oop object) { + assert(object != NULL, "invariant"); + if (object->is_array()) { + return arrayOop(object)->length(); + } + return -1; +} + +void EmitEventOperation::write_event(const ObjectSample* sample, EdgeStore* edge_store) { + assert(sample != NULL, "invariant"); + assert(!sample->is_dead(), "invariant"); + assert(edge_store != NULL, "invariant"); + assert(_vm_thread_data != NULL, "invariant"); + const oop* object_addr = sample->object_addr(); + assert(*object_addr != NULL, "invariant"); + + const Edge* edge = (const Edge*)(*object_addr)->mark(); + traceid gc_root_id = 0; + if (edge == NULL) { + // In order to dump out a representation of the event + // even though it was not reachable / too long to reach, + // we need to register a top level edge for this object + Edge e(NULL, object_addr); + edge_store->add_chain(&e, 1); + edge = (const Edge*)(*object_addr)->mark(); + } else { + gc_root_id = edge_store->get_root_id(edge); + } + + assert(edge != NULL, "invariant"); + assert(edge->pointee() == *object_addr, "invariant"); + const traceid object_id = edge_store->get_id(edge); + assert(object_id != 0, "invariant"); + + EventOldObjectSample e(UNTIMED); + e.set_starttime(GranularTimer::start_time()); + e.set_endtime(GranularTimer::end_time()); + e.set_allocationTime(sample->allocation_time()); + e.set_object(object_id); + e.set_arrayElements(array_size(*object_addr)); + e.set_root(gc_root_id); + + // Temporarily assigning both the stack trace id and thread id + // onto the thread local data structure of the VMThread (for the duration + // of the commit() call). This trick provides a means to override + // the event generation mechanism by injecting externally provided id's. + // Here, in particular, this allows us to emit an old object event + // supplying information from where the actual sampling occurred. + _vm_thread_data->set_cached_stack_trace_id(sample->stack_trace_id()); + assert(sample->has_thread(), "invariant"); + _vm_thread_data->set_thread_id(sample->thread_id()); + e.commit(); +}