--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/jfr/leakprofiler/emitEventOperation.cpp Tue May 15 20:24:34 2018 +0200
@@ -0,0 +1,233 @@
+/*
+ * Copyright (c) 2014, 2018, 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/shared/collectedHeap.hpp"
+#include "jfr/jfrEvents.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/checkpoint/jfrCheckpointWriter.hpp"
+#include "jfr/support/jfrThreadId.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 "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_local = _vm_thread->jfr_thread_local();
+ assert(_vm_thread_local != NULL, "invariant");
+ assert(_vm_thread->jfr_thread_local()->thread_id() == JFR_THREAD_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_local != 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_local->thread_id();
+ assert(_vm_thread_local->thread_id() == JFR_THREAD_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_local->set_thread_id(vmthread_id);
+ _vm_thread_local->clear_cached_stack_trace();
+ assert(_vm_thread_local->thread_id() == JFR_THREAD_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_local != 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_local->set_cached_stack_trace_id(sample->stack_trace_id());
+ assert(sample->has_thread(), "invariant");
+ _vm_thread_local->set_thread_id(sample->thread_id());
+ e.commit();
+}