--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/utilities/taskqueue.cpp Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,178 @@
+/*
+ * Copyright 2001-2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+# include "incls/_precompiled.incl"
+# include "incls/_taskqueue.cpp.incl"
+
+bool TaskQueueSuper::peek() {
+ return _bottom != _age.top();
+}
+
+int TaskQueueSetSuper::randomParkAndMiller(int *seed0) {
+ const int a = 16807;
+ const int m = 2147483647;
+ const int q = 127773; /* m div a */
+ const int r = 2836; /* m mod a */
+ assert(sizeof(int) == 4, "I think this relies on that");
+ int seed = *seed0;
+ int hi = seed / q;
+ int lo = seed % q;
+ int test = a * lo - r * hi;
+ if (test > 0)
+ seed = test;
+ else
+ seed = test + m;
+ *seed0 = seed;
+ return seed;
+}
+
+ParallelTaskTerminator::
+ParallelTaskTerminator(int n_threads, TaskQueueSetSuper* queue_set) :
+ _n_threads(n_threads),
+ _queue_set(queue_set),
+ _offered_termination(0) {}
+
+bool ParallelTaskTerminator::peek_in_queue_set() {
+ return _queue_set->peek();
+}
+
+void ParallelTaskTerminator::yield() {
+ os::yield();
+}
+
+void ParallelTaskTerminator::sleep(uint millis) {
+ os::sleep(Thread::current(), millis, false);
+}
+
+bool ParallelTaskTerminator::offer_termination() {
+ Atomic::inc(&_offered_termination);
+
+ juint yield_count = 0;
+ while (true) {
+ if (_offered_termination == _n_threads) {
+ //inner_termination_loop();
+ return true;
+ } else {
+ if (yield_count <= WorkStealingYieldsBeforeSleep) {
+ yield_count++;
+ yield();
+ } else {
+ if (PrintGCDetails && Verbose) {
+ gclog_or_tty->print_cr("ParallelTaskTerminator::offer_termination() "
+ "thread %d sleeps after %d yields",
+ Thread::current(), yield_count);
+ }
+ yield_count = 0;
+ // A sleep will cause this processor to seek work on another processor's
+ // runqueue, if it has nothing else to run (as opposed to the yield
+ // which may only move the thread to the end of the this processor's
+ // runqueue).
+ sleep(WorkStealingSleepMillis);
+ }
+
+ if (peek_in_queue_set()) {
+ Atomic::dec(&_offered_termination);
+ return false;
+ }
+ }
+ }
+}
+
+void ParallelTaskTerminator::reset_for_reuse() {
+ if (_offered_termination != 0) {
+ assert(_offered_termination == _n_threads,
+ "Terminator may still be in use");
+ _offered_termination = 0;
+ }
+}
+
+bool ChunkTaskQueueWithOverflow::is_empty() {
+ return (_chunk_queue.size() == 0) &&
+ (_overflow_stack->length() == 0);
+}
+
+bool ChunkTaskQueueWithOverflow::stealable_is_empty() {
+ return _chunk_queue.size() == 0;
+}
+
+bool ChunkTaskQueueWithOverflow::overflow_is_empty() {
+ return _overflow_stack->length() == 0;
+}
+
+void ChunkTaskQueueWithOverflow::initialize() {
+ _chunk_queue.initialize();
+ assert(_overflow_stack == 0, "Creating memory leak");
+ _overflow_stack =
+ new (ResourceObj::C_HEAP) GrowableArray<ChunkTask>(10, true);
+}
+
+void ChunkTaskQueueWithOverflow::save(ChunkTask t) {
+ if (TraceChunkTasksQueuing && Verbose) {
+ gclog_or_tty->print_cr("CTQ: save " PTR_FORMAT, t);
+ }
+ if(!_chunk_queue.push(t)) {
+ _overflow_stack->push(t);
+ }
+}
+
+// Note that using this method will retrieve all chunks
+// that have been saved but that it will always check
+// the overflow stack. It may be more efficient to
+// check the stealable queue and the overflow stack
+// separately.
+bool ChunkTaskQueueWithOverflow::retrieve(ChunkTask& chunk_task) {
+ bool result = retrieve_from_overflow(chunk_task);
+ if (!result) {
+ result = retrieve_from_stealable_queue(chunk_task);
+ }
+ if (TraceChunkTasksQueuing && Verbose && result) {
+ gclog_or_tty->print_cr(" CTQ: retrieve " PTR_FORMAT, result);
+ }
+ return result;
+}
+
+bool ChunkTaskQueueWithOverflow::retrieve_from_stealable_queue(
+ ChunkTask& chunk_task) {
+ bool result = _chunk_queue.pop_local(chunk_task);
+ if (TraceChunkTasksQueuing && Verbose) {
+ gclog_or_tty->print_cr("CTQ: retrieve_stealable " PTR_FORMAT, chunk_task);
+ }
+ return result;
+}
+
+bool ChunkTaskQueueWithOverflow::retrieve_from_overflow(
+ ChunkTask& chunk_task) {
+ bool result;
+ if (!_overflow_stack->is_empty()) {
+ chunk_task = _overflow_stack->pop();
+ result = true;
+ } else {
+ chunk_task = (ChunkTask) NULL;
+ result = false;
+ }
+ if (TraceChunkTasksQueuing && Verbose) {
+ gclog_or_tty->print_cr("CTQ: retrieve_stealable " PTR_FORMAT, chunk_task);
+ }
+ return result;
+}