--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/g1/g1DirtyCardQueue.cpp Wed Feb 13 17:38:14 2019 -0500
@@ -0,0 +1,236 @@
+/*
+ * Copyright (c) 2001, 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/g1/g1CollectedHeap.inline.hpp"
+#include "gc/g1/g1DirtyCardQueue.hpp"
+#include "gc/g1/g1FreeIdSet.hpp"
+#include "gc/g1/g1RemSet.hpp"
+#include "gc/g1/g1ThreadLocalData.hpp"
+#include "gc/g1/heapRegionRemSet.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
+#include "gc/shared/workgroup.hpp"
+#include "runtime/atomic.hpp"
+#include "runtime/flags/flagSetting.hpp"
+#include "runtime/mutexLocker.hpp"
+#include "runtime/safepoint.hpp"
+#include "runtime/thread.inline.hpp"
+#include "runtime/threadSMR.hpp"
+
+// Closure used for updating remembered sets and recording references that
+// point into the collection set while the mutator is running.
+// Assumed to be only executed concurrently with the mutator. Yields via
+// SuspendibleThreadSet after every card.
+class G1RefineCardConcurrentlyClosure: public G1CardTableEntryClosure {
+public:
+ bool do_card_ptr(jbyte* card_ptr, uint worker_i) {
+ G1CollectedHeap::heap()->g1_rem_set()->refine_card_concurrently(card_ptr, worker_i);
+
+ if (SuspendibleThreadSet::should_yield()) {
+ // Caller will actually yield.
+ return false;
+ }
+ // Otherwise, we finished successfully; return true.
+ return true;
+ }
+};
+
+G1DirtyCardQueue::G1DirtyCardQueue(G1DirtyCardQueueSet* qset, bool permanent) :
+ // Dirty card queues are always active, so we create them with their
+ // active field set to true.
+ PtrQueue(qset, permanent, true /* active */)
+{ }
+
+G1DirtyCardQueue::~G1DirtyCardQueue() {
+ if (!is_permanent()) {
+ flush();
+ }
+}
+
+G1DirtyCardQueueSet::G1DirtyCardQueueSet(bool notify_when_complete) :
+ PtrQueueSet(notify_when_complete),
+ _shared_dirty_card_queue(this, true /* permanent */),
+ _free_ids(NULL),
+ _processed_buffers_mut(0),
+ _processed_buffers_rs_thread(0),
+ _cur_par_buffer_node(NULL)
+{
+ _all_active = true;
+}
+
+G1DirtyCardQueueSet::~G1DirtyCardQueueSet() {
+ delete _free_ids;
+}
+
+// Determines how many mutator threads can process the buffers in parallel.
+uint G1DirtyCardQueueSet::num_par_ids() {
+ return (uint)os::initial_active_processor_count();
+}
+
+void G1DirtyCardQueueSet::initialize(Monitor* cbl_mon,
+ BufferNode::Allocator* allocator,
+ Mutex* lock,
+ bool init_free_ids) {
+ PtrQueueSet::initialize(cbl_mon, allocator);
+ _shared_dirty_card_queue.set_lock(lock);
+ if (init_free_ids) {
+ _free_ids = new G1FreeIdSet(0, num_par_ids());
+ }
+}
+
+void G1DirtyCardQueueSet::handle_zero_index_for_thread(JavaThread* t) {
+ G1ThreadLocalData::dirty_card_queue(t).handle_zero_index();
+}
+
+bool G1DirtyCardQueueSet::apply_closure_to_buffer(G1CardTableEntryClosure* cl,
+ BufferNode* node,
+ bool consume,
+ uint worker_i) {
+ if (cl == NULL) return true;
+ bool result = true;
+ void** buf = BufferNode::make_buffer_from_node(node);
+ size_t i = node->index();
+ size_t limit = buffer_size();
+ for ( ; i < limit; ++i) {
+ jbyte* card_ptr = static_cast<jbyte*>(buf[i]);
+ assert(card_ptr != NULL, "invariant");
+ if (!cl->do_card_ptr(card_ptr, worker_i)) {
+ result = false; // Incomplete processing.
+ break;
+ }
+ }
+ if (consume) {
+ assert(i <= buffer_size(), "invariant");
+ node->set_index(i);
+ }
+ return result;
+}
+
+#ifndef ASSERT
+#define assert_fully_consumed(node, buffer_size)
+#else
+#define assert_fully_consumed(node, buffer_size) \
+ do { \
+ size_t _afc_index = (node)->index(); \
+ size_t _afc_size = (buffer_size); \
+ assert(_afc_index == _afc_size, \
+ "Buffer was not fully consumed as claimed: index: " \
+ SIZE_FORMAT ", size: " SIZE_FORMAT, \
+ _afc_index, _afc_size); \
+ } while (0)
+#endif // ASSERT
+
+bool G1DirtyCardQueueSet::mut_process_buffer(BufferNode* node) {
+ guarantee(_free_ids != NULL, "must be");
+
+ uint worker_i = _free_ids->claim_par_id(); // temporarily claim an id
+ G1RefineCardConcurrentlyClosure cl;
+ bool result = apply_closure_to_buffer(&cl, node, true, worker_i);
+ _free_ids->release_par_id(worker_i); // release the id
+
+ if (result) {
+ assert_fully_consumed(node, buffer_size());
+ Atomic::inc(&_processed_buffers_mut);
+ }
+ return result;
+}
+
+bool G1DirtyCardQueueSet::refine_completed_buffer_concurrently(uint worker_i, size_t stop_at) {
+ G1RefineCardConcurrentlyClosure cl;
+ return apply_closure_to_completed_buffer(&cl, worker_i, stop_at, false);
+}
+
+bool G1DirtyCardQueueSet::apply_closure_during_gc(G1CardTableEntryClosure* cl, uint worker_i) {
+ assert_at_safepoint();
+ return apply_closure_to_completed_buffer(cl, worker_i, 0, true);
+}
+
+bool G1DirtyCardQueueSet::apply_closure_to_completed_buffer(G1CardTableEntryClosure* cl,
+ uint worker_i,
+ size_t stop_at,
+ bool during_pause) {
+ assert(!during_pause || stop_at == 0, "Should not leave any completed buffers during a pause");
+ BufferNode* nd = get_completed_buffer(stop_at);
+ if (nd == NULL) {
+ return false;
+ } else {
+ if (apply_closure_to_buffer(cl, nd, true, worker_i)) {
+ assert_fully_consumed(nd, buffer_size());
+ // Done with fully processed buffer.
+ deallocate_buffer(nd);
+ Atomic::inc(&_processed_buffers_rs_thread);
+ } else {
+ // Return partially processed buffer to the queue.
+ guarantee(!during_pause, "Should never stop early");
+ enqueue_completed_buffer(nd);
+ }
+ return true;
+ }
+}
+
+void G1DirtyCardQueueSet::par_apply_closure_to_all_completed_buffers(G1CardTableEntryClosure* cl) {
+ BufferNode* nd = _cur_par_buffer_node;
+ while (nd != NULL) {
+ BufferNode* next = nd->next();
+ BufferNode* actual = Atomic::cmpxchg(next, &_cur_par_buffer_node, nd);
+ if (actual == nd) {
+ bool b = apply_closure_to_buffer(cl, nd, false);
+ guarantee(b, "Should not stop early.");
+ nd = next;
+ } else {
+ nd = actual;
+ }
+ }
+}
+
+void G1DirtyCardQueueSet::abandon_logs() {
+ assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
+ abandon_completed_buffers();
+ // Since abandon is done only at safepoints, we can safely manipulate
+ // these queues.
+ for (JavaThreadIteratorWithHandle jtiwh; JavaThread *t = jtiwh.next(); ) {
+ G1ThreadLocalData::dirty_card_queue(t).reset();
+ }
+ shared_dirty_card_queue()->reset();
+}
+
+void G1DirtyCardQueueSet::concatenate_log(G1DirtyCardQueue& dcq) {
+ if (!dcq.is_empty()) {
+ dcq.flush();
+ }
+}
+
+void G1DirtyCardQueueSet::concatenate_logs() {
+ // Iterate over all the threads, if we find a partial log add it to
+ // the global list of logs. Temporarily turn off the limit on the number
+ // of outstanding buffers.
+ assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
+ size_t old_limit = max_completed_buffers();
+ set_max_completed_buffers(MaxCompletedBuffersUnlimited);
+ for (JavaThreadIteratorWithHandle jtiwh; JavaThread *t = jtiwh.next(); ) {
+ concatenate_log(G1ThreadLocalData::dirty_card_queue(t));
+ }
+ concatenate_log(_shared_dirty_card_queue);
+ set_max_completed_buffers(old_limit);
+}