truffle: src/share/vm/utilities/taskqueue.hpp annotate

annotate src/share/vm/utilities/taskqueue.hpp @ 546:05c6d52fa7a9

6690928: Use spinning in combination with yields for workstealing termination. Summary: Substitute a spin loop for most calls to yield() to reduce the stress on the system. Reviewed-by: tonyp

author	jmasa
date	Sun, 08 Feb 2009 13:18:01 -0800
parents	23673011938d
children	0fbdb4381b99

rev	line source
0 a61af66fc99e Initial load duke parents: diff changeset	1 /*
196 d1605aabd0a1 6719955: Update copyright year xdono parents: 113 diff changeset	2 * Copyright 2001-2008 Sun Microsystems, Inc. All Rights Reserved.
0 a61af66fc99e Initial load duke parents: diff changeset	3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
a61af66fc99e Initial load duke parents: diff changeset	4 *
a61af66fc99e Initial load duke parents: diff changeset	5 * This code is free software; you can redistribute it and/or modify it
a61af66fc99e Initial load duke parents: diff changeset	6 * under the terms of the GNU General Public License version 2 only, as
a61af66fc99e Initial load duke parents: diff changeset	7 * published by the Free Software Foundation.
a61af66fc99e Initial load duke parents: diff changeset	8 *
a61af66fc99e Initial load duke parents: diff changeset	9 * This code is distributed in the hope that it will be useful, but WITHOUT
a61af66fc99e Initial load duke parents: diff changeset	10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
a61af66fc99e Initial load duke parents: diff changeset	11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
a61af66fc99e Initial load duke parents: diff changeset	12 * version 2 for more details (a copy is included in the LICENSE file that
a61af66fc99e Initial load duke parents: diff changeset	13 * accompanied this code).
a61af66fc99e Initial load duke parents: diff changeset	14 *
a61af66fc99e Initial load duke parents: diff changeset	15 * You should have received a copy of the GNU General Public License version
a61af66fc99e Initial load duke parents: diff changeset	16 * 2 along with this work; if not, write to the Free Software Foundation,
a61af66fc99e Initial load duke parents: diff changeset	17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
a61af66fc99e Initial load duke parents: diff changeset	18 *
a61af66fc99e Initial load duke parents: diff changeset	19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
a61af66fc99e Initial load duke parents: diff changeset	20 * CA 95054 USA or visit www.sun.com if you need additional information or
a61af66fc99e Initial load duke parents: diff changeset	21 * have any questions.
a61af66fc99e Initial load duke parents: diff changeset	22 *
a61af66fc99e Initial load duke parents: diff changeset	23 */
a61af66fc99e Initial load duke parents: diff changeset	24
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	25 #ifdef LP64
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	26 typedef juint TAG_TYPE;
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	27 // for a taskqueue size of 4M
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	28 #define LOG_TASKQ_SIZE 22
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	29 #else
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	30 typedef jushort TAG_TYPE;
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	31 // for a taskqueue size of 16K
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	32 #define LOG_TASKQ_SIZE 14
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	33 #endif
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	34
0 a61af66fc99e Initial load duke parents: diff changeset	35 class TaskQueueSuper: public CHeapObj {
a61af66fc99e Initial load duke parents: diff changeset	36 protected:
a61af66fc99e Initial load duke parents: diff changeset	37 // The first free element after the last one pushed (mod _n).
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	38 volatile uint _bottom;
0 a61af66fc99e Initial load duke parents: diff changeset	39
a61af66fc99e Initial load duke parents: diff changeset	40 // log2 of the size of the queue.
a61af66fc99e Initial load duke parents: diff changeset	41 enum SomeProtectedConstants {
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	42 Log_n = LOG_TASKQ_SIZE
0 a61af66fc99e Initial load duke parents: diff changeset	43 };
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	44 #undef LOG_TASKQ_SIZE
0 a61af66fc99e Initial load duke parents: diff changeset	45
a61af66fc99e Initial load duke parents: diff changeset	46 // Size of the queue.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	47 uint n() { return (1 << Log_n); }
0 a61af66fc99e Initial load duke parents: diff changeset	48 // For computing "x mod n" efficiently.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	49 uint n_mod_mask() { return n() - 1; }
0 a61af66fc99e Initial load duke parents: diff changeset	50
a61af66fc99e Initial load duke parents: diff changeset	51 struct Age {
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	52 TAG_TYPE _top;
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	53 TAG_TYPE _tag;
0 a61af66fc99e Initial load duke parents: diff changeset	54
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	55 TAG_TYPE tag() const { return _tag; }
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	56 TAG_TYPE top() const { return _top; }
0 a61af66fc99e Initial load duke parents: diff changeset	57
a61af66fc99e Initial load duke parents: diff changeset	58 Age() { _tag = 0; _top = 0; }
a61af66fc99e Initial load duke parents: diff changeset	59
a61af66fc99e Initial load duke parents: diff changeset	60 friend bool operator ==(const Age& a1, const Age& a2) {
a61af66fc99e Initial load duke parents: diff changeset	61 return a1.tag() == a2.tag() && a1.top() == a2.top();
a61af66fc99e Initial load duke parents: diff changeset	62 }
a61af66fc99e Initial load duke parents: diff changeset	63 };
a61af66fc99e Initial load duke parents: diff changeset	64 Age _age;
a61af66fc99e Initial load duke parents: diff changeset	65 // These make sure we do single atomic reads and writes.
a61af66fc99e Initial load duke parents: diff changeset	66 Age get_age() {
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	67 uint res = (volatile uint)(&_age);
0 a61af66fc99e Initial load duke parents: diff changeset	68 return (Age)(&res);
a61af66fc99e Initial load duke parents: diff changeset	69 }
a61af66fc99e Initial load duke parents: diff changeset	70 void set_age(Age a) {
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	71 (volatile uint)(&_age) = (uint)(&a);
0 a61af66fc99e Initial load duke parents: diff changeset	72 }
a61af66fc99e Initial load duke parents: diff changeset	73
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	74 TAG_TYPE get_top() {
0 a61af66fc99e Initial load duke parents: diff changeset	75 return get_age().top();
a61af66fc99e Initial load duke parents: diff changeset	76 }
a61af66fc99e Initial load duke parents: diff changeset	77
a61af66fc99e Initial load duke parents: diff changeset	78 // These both operate mod _n.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	79 uint increment_index(uint ind) {
0 a61af66fc99e Initial load duke parents: diff changeset	80 return (ind + 1) & n_mod_mask();
a61af66fc99e Initial load duke parents: diff changeset	81 }
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	82 uint decrement_index(uint ind) {
0 a61af66fc99e Initial load duke parents: diff changeset	83 return (ind - 1) & n_mod_mask();
a61af66fc99e Initial load duke parents: diff changeset	84 }
a61af66fc99e Initial load duke parents: diff changeset	85
a61af66fc99e Initial load duke parents: diff changeset	86 // Returns a number in the range [0.._n). If the result is "n-1", it
a61af66fc99e Initial load duke parents: diff changeset	87 // should be interpreted as 0.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	88 uint dirty_size(uint bot, uint top) {
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	89 return ((int)bot - (int)top) & n_mod_mask();
0 a61af66fc99e Initial load duke parents: diff changeset	90 }
a61af66fc99e Initial load duke parents: diff changeset	91
a61af66fc99e Initial load duke parents: diff changeset	92 // Returns the size corresponding to the given "bot" and "top".
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	93 uint size(uint bot, uint top) {
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	94 uint sz = dirty_size(bot, top);
0 a61af66fc99e Initial load duke parents: diff changeset	95 // Has the queue "wrapped", so that bottom is less than top?
a61af66fc99e Initial load duke parents: diff changeset	96 // There's a complicated special case here. A pair of threads could
a61af66fc99e Initial load duke parents: diff changeset	97 // perform pop_local and pop_global operations concurrently, starting
a61af66fc99e Initial load duke parents: diff changeset	98 // from a state in which _bottom == _top+1. The pop_local could
a61af66fc99e Initial load duke parents: diff changeset	99 // succeed in decrementing _bottom, and the pop_global in incrementing
a61af66fc99e Initial load duke parents: diff changeset	100 // _top (in which case the pop_global will be awarded the contested
a61af66fc99e Initial load duke parents: diff changeset	101 // queue element.) The resulting state must be interpreted as an empty
a61af66fc99e Initial load duke parents: diff changeset	102 // queue. (We only need to worry about one such event: only the queue
a61af66fc99e Initial load duke parents: diff changeset	103 // owner performs pop_local's, and several concurrent threads
a61af66fc99e Initial load duke parents: diff changeset	104 // attempting to perform the pop_global will all perform the same CAS,
a61af66fc99e Initial load duke parents: diff changeset	105 // and only one can succeed. Any stealing thread that reads after
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	106 // either the increment or decrement will see an empty queue, and will
0 a61af66fc99e Initial load duke parents: diff changeset	107 // not join the competitors. The "sz == -1 \|\| sz == _n-1" state will
a61af66fc99e Initial load duke parents: diff changeset	108 // not be modified by concurrent queues, so the owner thread can reset
a61af66fc99e Initial load duke parents: diff changeset	109 // the state to _bottom == top so subsequent pushes will be performed
a61af66fc99e Initial load duke parents: diff changeset	110 // normally.
a61af66fc99e Initial load duke parents: diff changeset	111 if (sz == (n()-1)) return 0;
a61af66fc99e Initial load duke parents: diff changeset	112 else return sz;
a61af66fc99e Initial load duke parents: diff changeset	113 }
a61af66fc99e Initial load duke parents: diff changeset	114
a61af66fc99e Initial load duke parents: diff changeset	115 public:
a61af66fc99e Initial load duke parents: diff changeset	116 TaskQueueSuper() : _bottom(0), _age() {}
a61af66fc99e Initial load duke parents: diff changeset	117
a61af66fc99e Initial load duke parents: diff changeset	118 // Return "true" if the TaskQueue contains any tasks.
a61af66fc99e Initial load duke parents: diff changeset	119 bool peek();
a61af66fc99e Initial load duke parents: diff changeset	120
a61af66fc99e Initial load duke parents: diff changeset	121 // Return an estimate of the number of elements in the queue.
a61af66fc99e Initial load duke parents: diff changeset	122 // The "careful" version admits the possibility of pop_local/pop_global
a61af66fc99e Initial load duke parents: diff changeset	123 // races.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	124 uint size() {
0 a61af66fc99e Initial load duke parents: diff changeset	125 return size(_bottom, get_top());
a61af66fc99e Initial load duke parents: diff changeset	126 }
a61af66fc99e Initial load duke parents: diff changeset	127
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	128 uint dirty_size() {
0 a61af66fc99e Initial load duke parents: diff changeset	129 return dirty_size(_bottom, get_top());
a61af66fc99e Initial load duke parents: diff changeset	130 }
a61af66fc99e Initial load duke parents: diff changeset	131
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	132 void set_empty() {
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	133 _bottom = 0;
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	134 _age = Age();
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	135 }
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	136
0 a61af66fc99e Initial load duke parents: diff changeset	137 // Maximum number of elements allowed in the queue. This is two less
a61af66fc99e Initial load duke parents: diff changeset	138 // than the actual queue size, for somewhat complicated reasons.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	139 uint max_elems() { return n() - 2; }
0 a61af66fc99e Initial load duke parents: diff changeset	140
a61af66fc99e Initial load duke parents: diff changeset	141 };
a61af66fc99e Initial load duke parents: diff changeset	142
a61af66fc99e Initial load duke parents: diff changeset	143 template<class E> class GenericTaskQueue: public TaskQueueSuper {
a61af66fc99e Initial load duke parents: diff changeset	144 private:
a61af66fc99e Initial load duke parents: diff changeset	145 // Slow paths for push, pop_local. (pop_global has no fast path.)
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	146 bool push_slow(E t, uint dirty_n_elems);
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	147 bool pop_local_slow(uint localBot, Age oldAge);
0 a61af66fc99e Initial load duke parents: diff changeset	148
a61af66fc99e Initial load duke parents: diff changeset	149 public:
a61af66fc99e Initial load duke parents: diff changeset	150 // Initializes the queue to empty.
a61af66fc99e Initial load duke parents: diff changeset	151 GenericTaskQueue();
a61af66fc99e Initial load duke parents: diff changeset	152
a61af66fc99e Initial load duke parents: diff changeset	153 void initialize();
a61af66fc99e Initial load duke parents: diff changeset	154
a61af66fc99e Initial load duke parents: diff changeset	155 // Push the task "t" on the queue. Returns "false" iff the queue is
a61af66fc99e Initial load duke parents: diff changeset	156 // full.
a61af66fc99e Initial load duke parents: diff changeset	157 inline bool push(E t);
a61af66fc99e Initial load duke parents: diff changeset	158
a61af66fc99e Initial load duke parents: diff changeset	159 // If succeeds in claiming a task (from the 'local' end, that is, the
a61af66fc99e Initial load duke parents: diff changeset	160 // most recently pushed task), returns "true" and sets "t" to that task.
a61af66fc99e Initial load duke parents: diff changeset	161 // Otherwise, the queue is empty and returns false.
a61af66fc99e Initial load duke parents: diff changeset	162 inline bool pop_local(E& t);
a61af66fc99e Initial load duke parents: diff changeset	163
a61af66fc99e Initial load duke parents: diff changeset	164 // If succeeds in claiming a task (from the 'global' end, that is, the
a61af66fc99e Initial load duke parents: diff changeset	165 // least recently pushed task), returns "true" and sets "t" to that task.
a61af66fc99e Initial load duke parents: diff changeset	166 // Otherwise, the queue is empty and returns false.
a61af66fc99e Initial load duke parents: diff changeset	167 bool pop_global(E& t);
a61af66fc99e Initial load duke parents: diff changeset	168
a61af66fc99e Initial load duke parents: diff changeset	169 // Delete any resource associated with the queue.
a61af66fc99e Initial load duke parents: diff changeset	170 ~GenericTaskQueue();
a61af66fc99e Initial load duke parents: diff changeset	171
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	172 // apply the closure to all elements in the task queue
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	173 void oops_do(OopClosure* f);
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	174
0 a61af66fc99e Initial load duke parents: diff changeset	175 private:
a61af66fc99e Initial load duke parents: diff changeset	176 // Element array.
a61af66fc99e Initial load duke parents: diff changeset	177 volatile E* _elems;
a61af66fc99e Initial load duke parents: diff changeset	178 };
a61af66fc99e Initial load duke parents: diff changeset	179
a61af66fc99e Initial load duke parents: diff changeset	180 template<class E>
a61af66fc99e Initial load duke parents: diff changeset	181 GenericTaskQueue<E>::GenericTaskQueue():TaskQueueSuper() {
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	182 assert(sizeof(Age) == sizeof(int), "Depends on this.");
0 a61af66fc99e Initial load duke parents: diff changeset	183 }
a61af66fc99e Initial load duke parents: diff changeset	184
a61af66fc99e Initial load duke parents: diff changeset	185 template<class E>
a61af66fc99e Initial load duke parents: diff changeset	186 void GenericTaskQueue<E>::initialize() {
a61af66fc99e Initial load duke parents: diff changeset	187 _elems = NEW_C_HEAP_ARRAY(E, n());
a61af66fc99e Initial load duke parents: diff changeset	188 guarantee(_elems != NULL, "Allocation failed.");
a61af66fc99e Initial load duke parents: diff changeset	189 }
a61af66fc99e Initial load duke parents: diff changeset	190
a61af66fc99e Initial load duke parents: diff changeset	191 template<class E>
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	192 void GenericTaskQueue<E>::oops_do(OopClosure* f) {
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	193 // tty->print_cr("START OopTaskQueue::oops_do");
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	194 uint iters = size();
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	195 uint index = _bottom;
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	196 for (uint i = 0; i < iters; ++i) {
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	197 index = decrement_index(index);
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	198 // tty->print_cr(" doing entry %d," INTPTR_T " -> " INTPTR_T,
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	199 // index, &_elems[index], _elems[index]);
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	200 E* t = (E*)&_elems[index]; // cast away volatility
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	201 oop* p = (oop*)t;
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	202 assert((*t)->is_oop_or_null(), "Not an oop or null");
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	203 f->do_oop(p);
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	204 }
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	205 // tty->print_cr("END OopTaskQueue::oops_do");
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	206 }
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	207
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	208
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	209 template<class E>
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	210 bool GenericTaskQueue<E>::push_slow(E t, uint dirty_n_elems) {
0 a61af66fc99e Initial load duke parents: diff changeset	211 if (dirty_n_elems == n() - 1) {
a61af66fc99e Initial load duke parents: diff changeset	212 // Actually means 0, so do the push.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	213 uint localBot = _bottom;
0 a61af66fc99e Initial load duke parents: diff changeset	214 _elems[localBot] = t;
a61af66fc99e Initial load duke parents: diff changeset	215 _bottom = increment_index(localBot);
a61af66fc99e Initial load duke parents: diff changeset	216 return true;
a61af66fc99e Initial load duke parents: diff changeset	217 } else
a61af66fc99e Initial load duke parents: diff changeset	218 return false;
a61af66fc99e Initial load duke parents: diff changeset	219 }
a61af66fc99e Initial load duke parents: diff changeset	220
a61af66fc99e Initial load duke parents: diff changeset	221 template<class E>
a61af66fc99e Initial load duke parents: diff changeset	222 bool GenericTaskQueue<E>::
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	223 pop_local_slow(uint localBot, Age oldAge) {
0 a61af66fc99e Initial load duke parents: diff changeset	224 // This queue was observed to contain exactly one element; either this
a61af66fc99e Initial load duke parents: diff changeset	225 // thread will claim it, or a competing "pop_global". In either case,
a61af66fc99e Initial load duke parents: diff changeset	226 // the queue will be logically empty afterwards. Create a new Age value
a61af66fc99e Initial load duke parents: diff changeset	227 // that represents the empty queue for the given value of "_bottom". (We
a61af66fc99e Initial load duke parents: diff changeset	228 // must also increment "tag" because of the case where "bottom == 1",
a61af66fc99e Initial load duke parents: diff changeset	229 // "top == 0". A pop_global could read the queue element in that case,
a61af66fc99e Initial load duke parents: diff changeset	230 // then have the owner thread do a pop followed by another push. Without
a61af66fc99e Initial load duke parents: diff changeset	231 // the incrementing of "tag", the pop_global's CAS could succeed,
a61af66fc99e Initial load duke parents: diff changeset	232 // allowing it to believe it has claimed the stale element.)
a61af66fc99e Initial load duke parents: diff changeset	233 Age newAge;
a61af66fc99e Initial load duke parents: diff changeset	234 newAge._top = localBot;
a61af66fc99e Initial load duke parents: diff changeset	235 newAge._tag = oldAge.tag() + 1;
a61af66fc99e Initial load duke parents: diff changeset	236 // Perhaps a competing pop_global has already incremented "top", in which
a61af66fc99e Initial load duke parents: diff changeset	237 // case it wins the element.
a61af66fc99e Initial load duke parents: diff changeset	238 if (localBot == oldAge.top()) {
a61af66fc99e Initial load duke parents: diff changeset	239 Age tempAge;
a61af66fc99e Initial load duke parents: diff changeset	240 // No competing pop_global has yet incremented "top"; we'll try to
a61af66fc99e Initial load duke parents: diff changeset	241 // install new_age, thus claiming the element.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	242 assert(sizeof(Age) == sizeof(int), "Assumption about CAS unit.");
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	243 (uint)&tempAge = Atomic::cmpxchg((uint)&newAge, (volatile uint)&_age, (uint*)&oldAge);
0 a61af66fc99e Initial load duke parents: diff changeset	244 if (tempAge == oldAge) {
a61af66fc99e Initial load duke parents: diff changeset	245 // We win.
a61af66fc99e Initial load duke parents: diff changeset	246 assert(dirty_size(localBot, get_top()) != n() - 1,
a61af66fc99e Initial load duke parents: diff changeset	247 "Shouldn't be possible...");
a61af66fc99e Initial load duke parents: diff changeset	248 return true;
a61af66fc99e Initial load duke parents: diff changeset	249 }
a61af66fc99e Initial load duke parents: diff changeset	250 }
a61af66fc99e Initial load duke parents: diff changeset	251 // We fail; a completing pop_global gets the element. But the queue is
a61af66fc99e Initial load duke parents: diff changeset	252 // empty (and top is greater than bottom.) Fix this representation of
a61af66fc99e Initial load duke parents: diff changeset	253 // the empty queue to become the canonical one.
a61af66fc99e Initial load duke parents: diff changeset	254 set_age(newAge);
a61af66fc99e Initial load duke parents: diff changeset	255 assert(dirty_size(localBot, get_top()) != n() - 1,
a61af66fc99e Initial load duke parents: diff changeset	256 "Shouldn't be possible...");
a61af66fc99e Initial load duke parents: diff changeset	257 return false;
a61af66fc99e Initial load duke parents: diff changeset	258 }
a61af66fc99e Initial load duke parents: diff changeset	259
a61af66fc99e Initial load duke parents: diff changeset	260 template<class E>
a61af66fc99e Initial load duke parents: diff changeset	261 bool GenericTaskQueue<E>::pop_global(E& t) {
a61af66fc99e Initial load duke parents: diff changeset	262 Age newAge;
a61af66fc99e Initial load duke parents: diff changeset	263 Age oldAge = get_age();
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	264 uint localBot = _bottom;
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	265 uint n_elems = size(localBot, oldAge.top());
0 a61af66fc99e Initial load duke parents: diff changeset	266 if (n_elems == 0) {
a61af66fc99e Initial load duke parents: diff changeset	267 return false;
a61af66fc99e Initial load duke parents: diff changeset	268 }
a61af66fc99e Initial load duke parents: diff changeset	269 t = _elems[oldAge.top()];
a61af66fc99e Initial load duke parents: diff changeset	270 newAge = oldAge;
a61af66fc99e Initial load duke parents: diff changeset	271 newAge._top = increment_index(newAge.top());
a61af66fc99e Initial load duke parents: diff changeset	272 if ( newAge._top == 0 ) newAge._tag++;
a61af66fc99e Initial load duke parents: diff changeset	273 Age resAge;
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	274 (uint)&resAge = Atomic::cmpxchg((uint)&newAge, (volatile uint)&_age, (uint*)&oldAge);
0 a61af66fc99e Initial load duke parents: diff changeset	275 // Note that using "_bottom" here might fail, since a pop_local might
a61af66fc99e Initial load duke parents: diff changeset	276 // have decremented it.
a61af66fc99e Initial load duke parents: diff changeset	277 assert(dirty_size(localBot, newAge._top) != n() - 1,
a61af66fc99e Initial load duke parents: diff changeset	278 "Shouldn't be possible...");
a61af66fc99e Initial load duke parents: diff changeset	279 return (resAge == oldAge);
a61af66fc99e Initial load duke parents: diff changeset	280 }
a61af66fc99e Initial load duke parents: diff changeset	281
a61af66fc99e Initial load duke parents: diff changeset	282 template<class E>
a61af66fc99e Initial load duke parents: diff changeset	283 GenericTaskQueue<E>::~GenericTaskQueue() {
a61af66fc99e Initial load duke parents: diff changeset	284 FREE_C_HEAP_ARRAY(E, _elems);
a61af66fc99e Initial load duke parents: diff changeset	285 }
a61af66fc99e Initial load duke parents: diff changeset	286
a61af66fc99e Initial load duke parents: diff changeset	287 // Inherits the typedef of "Task" from above.
a61af66fc99e Initial load duke parents: diff changeset	288 class TaskQueueSetSuper: public CHeapObj {
a61af66fc99e Initial load duke parents: diff changeset	289 protected:
a61af66fc99e Initial load duke parents: diff changeset	290 static int randomParkAndMiller(int* seed0);
a61af66fc99e Initial load duke parents: diff changeset	291 public:
a61af66fc99e Initial load duke parents: diff changeset	292 // Returns "true" if some TaskQueue in the set contains a task.
a61af66fc99e Initial load duke parents: diff changeset	293 virtual bool peek() = 0;
a61af66fc99e Initial load duke parents: diff changeset	294 };
a61af66fc99e Initial load duke parents: diff changeset	295
a61af66fc99e Initial load duke parents: diff changeset	296 template<class E> class GenericTaskQueueSet: public TaskQueueSetSuper {
a61af66fc99e Initial load duke parents: diff changeset	297 private:
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	298 uint _n;
0 a61af66fc99e Initial load duke parents: diff changeset	299 GenericTaskQueue<E>** _queues;
a61af66fc99e Initial load duke parents: diff changeset	300
a61af66fc99e Initial load duke parents: diff changeset	301 public:
a61af66fc99e Initial load duke parents: diff changeset	302 GenericTaskQueueSet(int n) : _n(n) {
a61af66fc99e Initial load duke parents: diff changeset	303 typedef GenericTaskQueue<E>* GenericTaskQueuePtr;
a61af66fc99e Initial load duke parents: diff changeset	304 _queues = NEW_C_HEAP_ARRAY(GenericTaskQueuePtr, n);
a61af66fc99e Initial load duke parents: diff changeset	305 guarantee(_queues != NULL, "Allocation failure.");
a61af66fc99e Initial load duke parents: diff changeset	306 for (int i = 0; i < n; i++) {
a61af66fc99e Initial load duke parents: diff changeset	307 _queues[i] = NULL;
a61af66fc99e Initial load duke parents: diff changeset	308 }
a61af66fc99e Initial load duke parents: diff changeset	309 }
a61af66fc99e Initial load duke parents: diff changeset	310
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	311 bool steal_1_random(uint queue_num, int* seed, E& t);
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	312 bool steal_best_of_2(uint queue_num, int* seed, E& t);
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	313 bool steal_best_of_all(uint queue_num, int* seed, E& t);
0 a61af66fc99e Initial load duke parents: diff changeset	314
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	315 void register_queue(uint i, GenericTaskQueue<E>* q);
0 a61af66fc99e Initial load duke parents: diff changeset	316
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	317 GenericTaskQueue<E>* queue(uint n);
0 a61af66fc99e Initial load duke parents: diff changeset	318
a61af66fc99e Initial load duke parents: diff changeset	319 // The thread with queue number "queue_num" (and whose random number seed
a61af66fc99e Initial load duke parents: diff changeset	320 // is at "seed") is trying to steal a task from some other queue. (It
a61af66fc99e Initial load duke parents: diff changeset	321 // may try several queues, according to some configuration parameter.)
a61af66fc99e Initial load duke parents: diff changeset	322 // If some steal succeeds, returns "true" and sets "t" the stolen task,
a61af66fc99e Initial load duke parents: diff changeset	323 // otherwise returns false.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	324 bool steal(uint queue_num, int* seed, E& t);
0 a61af66fc99e Initial load duke parents: diff changeset	325
a61af66fc99e Initial load duke parents: diff changeset	326 bool peek();
a61af66fc99e Initial load duke parents: diff changeset	327 };
a61af66fc99e Initial load duke parents: diff changeset	328
a61af66fc99e Initial load duke parents: diff changeset	329 template<class E>
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	330 void GenericTaskQueueSet<E>::register_queue(uint i, GenericTaskQueue<E>* q) {
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	331 assert(i < _n, "index out of range.");
0 a61af66fc99e Initial load duke parents: diff changeset	332 _queues[i] = q;
a61af66fc99e Initial load duke parents: diff changeset	333 }
a61af66fc99e Initial load duke parents: diff changeset	334
a61af66fc99e Initial load duke parents: diff changeset	335 template<class E>
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	336 GenericTaskQueue<E>* GenericTaskQueueSet<E>::queue(uint i) {
0 a61af66fc99e Initial load duke parents: diff changeset	337 return _queues[i];
a61af66fc99e Initial load duke parents: diff changeset	338 }
a61af66fc99e Initial load duke parents: diff changeset	339
a61af66fc99e Initial load duke parents: diff changeset	340 template<class E>
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	341 bool GenericTaskQueueSet<E>::steal(uint queue_num, int* seed, E& t) {
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	342 for (uint i = 0; i < 2 * _n; i++)
0 a61af66fc99e Initial load duke parents: diff changeset	343 if (steal_best_of_2(queue_num, seed, t))
a61af66fc99e Initial load duke parents: diff changeset	344 return true;
a61af66fc99e Initial load duke parents: diff changeset	345 return false;
a61af66fc99e Initial load duke parents: diff changeset	346 }
a61af66fc99e Initial load duke parents: diff changeset	347
a61af66fc99e Initial load duke parents: diff changeset	348 template<class E>
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	349 bool GenericTaskQueueSet<E>::steal_best_of_all(uint queue_num, int* seed, E& t) {
0 a61af66fc99e Initial load duke parents: diff changeset	350 if (_n > 2) {
a61af66fc99e Initial load duke parents: diff changeset	351 int best_k;
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	352 uint best_sz = 0;
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	353 for (uint k = 0; k < _n; k++) {
0 a61af66fc99e Initial load duke parents: diff changeset	354 if (k == queue_num) continue;
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	355 uint sz = _queues[k]->size();
0 a61af66fc99e Initial load duke parents: diff changeset	356 if (sz > best_sz) {
a61af66fc99e Initial load duke parents: diff changeset	357 best_sz = sz;
a61af66fc99e Initial load duke parents: diff changeset	358 best_k = k;
a61af66fc99e Initial load duke parents: diff changeset	359 }
a61af66fc99e Initial load duke parents: diff changeset	360 }
a61af66fc99e Initial load duke parents: diff changeset	361 return best_sz > 0 && _queues[best_k]->pop_global(t);
a61af66fc99e Initial load duke parents: diff changeset	362 } else if (_n == 2) {
a61af66fc99e Initial load duke parents: diff changeset	363 // Just try the other one.
a61af66fc99e Initial load duke parents: diff changeset	364 int k = (queue_num + 1) % 2;
a61af66fc99e Initial load duke parents: diff changeset	365 return _queues[k]->pop_global(t);
a61af66fc99e Initial load duke parents: diff changeset	366 } else {
a61af66fc99e Initial load duke parents: diff changeset	367 assert(_n == 1, "can't be zero.");
a61af66fc99e Initial load duke parents: diff changeset	368 return false;
a61af66fc99e Initial load duke parents: diff changeset	369 }
a61af66fc99e Initial load duke parents: diff changeset	370 }
a61af66fc99e Initial load duke parents: diff changeset	371
a61af66fc99e Initial load duke parents: diff changeset	372 template<class E>
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	373 bool GenericTaskQueueSet<E>::steal_1_random(uint queue_num, int* seed, E& t) {
0 a61af66fc99e Initial load duke parents: diff changeset	374 if (_n > 2) {
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	375 uint k = queue_num;
0 a61af66fc99e Initial load duke parents: diff changeset	376 while (k == queue_num) k = randomParkAndMiller(seed) % _n;
a61af66fc99e Initial load duke parents: diff changeset	377 return _queues[2]->pop_global(t);
a61af66fc99e Initial load duke parents: diff changeset	378 } else if (_n == 2) {
a61af66fc99e Initial load duke parents: diff changeset	379 // Just try the other one.
a61af66fc99e Initial load duke parents: diff changeset	380 int k = (queue_num + 1) % 2;
a61af66fc99e Initial load duke parents: diff changeset	381 return _queues[k]->pop_global(t);
a61af66fc99e Initial load duke parents: diff changeset	382 } else {
a61af66fc99e Initial load duke parents: diff changeset	383 assert(_n == 1, "can't be zero.");
a61af66fc99e Initial load duke parents: diff changeset	384 return false;
a61af66fc99e Initial load duke parents: diff changeset	385 }
a61af66fc99e Initial load duke parents: diff changeset	386 }
a61af66fc99e Initial load duke parents: diff changeset	387
a61af66fc99e Initial load duke parents: diff changeset	388 template<class E>
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	389 bool GenericTaskQueueSet<E>::steal_best_of_2(uint queue_num, int* seed, E& t) {
0 a61af66fc99e Initial load duke parents: diff changeset	390 if (_n > 2) {
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	391 uint k1 = queue_num;
0 a61af66fc99e Initial load duke parents: diff changeset	392 while (k1 == queue_num) k1 = randomParkAndMiller(seed) % _n;
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	393 uint k2 = queue_num;
0 a61af66fc99e Initial load duke parents: diff changeset	394 while (k2 == queue_num \|\| k2 == k1) k2 = randomParkAndMiller(seed) % _n;
a61af66fc99e Initial load duke parents: diff changeset	395 // Sample both and try the larger.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	396 uint sz1 = _queues[k1]->size();
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	397 uint sz2 = _queues[k2]->size();
0 a61af66fc99e Initial load duke parents: diff changeset	398 if (sz2 > sz1) return _queues[k2]->pop_global(t);
a61af66fc99e Initial load duke parents: diff changeset	399 else return _queues[k1]->pop_global(t);
a61af66fc99e Initial load duke parents: diff changeset	400 } else if (_n == 2) {
a61af66fc99e Initial load duke parents: diff changeset	401 // Just try the other one.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	402 uint k = (queue_num + 1) % 2;
0 a61af66fc99e Initial load duke parents: diff changeset	403 return _queues[k]->pop_global(t);
a61af66fc99e Initial load duke parents: diff changeset	404 } else {
a61af66fc99e Initial load duke parents: diff changeset	405 assert(_n == 1, "can't be zero.");
a61af66fc99e Initial load duke parents: diff changeset	406 return false;
a61af66fc99e Initial load duke parents: diff changeset	407 }
a61af66fc99e Initial load duke parents: diff changeset	408 }
a61af66fc99e Initial load duke parents: diff changeset	409
a61af66fc99e Initial load duke parents: diff changeset	410 template<class E>
a61af66fc99e Initial load duke parents: diff changeset	411 bool GenericTaskQueueSet<E>::peek() {
a61af66fc99e Initial load duke parents: diff changeset	412 // Try all the queues.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	413 for (uint j = 0; j < _n; j++) {
0 a61af66fc99e Initial load duke parents: diff changeset	414 if (_queues[j]->peek())
a61af66fc99e Initial load duke parents: diff changeset	415 return true;
a61af66fc99e Initial load duke parents: diff changeset	416 }
a61af66fc99e Initial load duke parents: diff changeset	417 return false;
a61af66fc99e Initial load duke parents: diff changeset	418 }
a61af66fc99e Initial load duke parents: diff changeset	419
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	420 // When to terminate from the termination protocol.
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	421 class TerminatorTerminator: public CHeapObj {
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	422 public:
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	423 virtual bool should_exit_termination() = 0;
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	424 };
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	425
0 a61af66fc99e Initial load duke parents: diff changeset	426 // A class to aid in the termination of a set of parallel tasks using
a61af66fc99e Initial load duke parents: diff changeset	427 // TaskQueueSet's for work stealing.
a61af66fc99e Initial load duke parents: diff changeset	428
546 05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	429 #undef TRACESPINNING
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	430
0 a61af66fc99e Initial load duke parents: diff changeset	431 class ParallelTaskTerminator: public StackObj {
a61af66fc99e Initial load duke parents: diff changeset	432 private:
a61af66fc99e Initial load duke parents: diff changeset	433 int _n_threads;
a61af66fc99e Initial load duke parents: diff changeset	434 TaskQueueSetSuper* _queue_set;
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	435 int _offered_termination;
0 a61af66fc99e Initial load duke parents: diff changeset	436
546 05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	437 #ifdef TRACESPINNING
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	438 static uint _total_yields;
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	439 static uint _total_spins;
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	440 static uint _total_peeks;
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	441 #endif
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	442
0 a61af66fc99e Initial load duke parents: diff changeset	443 bool peek_in_queue_set();
a61af66fc99e Initial load duke parents: diff changeset	444 protected:
a61af66fc99e Initial load duke parents: diff changeset	445 virtual void yield();
a61af66fc99e Initial load duke parents: diff changeset	446 void sleep(uint millis);
a61af66fc99e Initial load duke parents: diff changeset	447
a61af66fc99e Initial load duke parents: diff changeset	448 public:
a61af66fc99e Initial load duke parents: diff changeset	449
a61af66fc99e Initial load duke parents: diff changeset	450 // "n_threads" is the number of threads to be terminated. "queue_set" is a
a61af66fc99e Initial load duke parents: diff changeset	451 // queue sets of work queues of other threads.
a61af66fc99e Initial load duke parents: diff changeset	452 ParallelTaskTerminator(int n_threads, TaskQueueSetSuper* queue_set);
a61af66fc99e Initial load duke parents: diff changeset	453
a61af66fc99e Initial load duke parents: diff changeset	454 // The current thread has no work, and is ready to terminate if everyone
a61af66fc99e Initial load duke parents: diff changeset	455 // else is. If returns "true", all threads are terminated. If returns
a61af66fc99e Initial load duke parents: diff changeset	456 // "false", available work has been observed in one of the task queues,
a61af66fc99e Initial load duke parents: diff changeset	457 // so the global task is not complete.
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	458 bool offer_termination() {
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	459 return offer_termination(NULL);
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	460 }
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	461
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	462 // As above, but it also terminates of the should_exit_termination()
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	463 // method of the terminator parameter returns true. If terminator is
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	464 // NULL, then it is ignored.
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	465 bool offer_termination(TerminatorTerminator* terminator);
0 a61af66fc99e Initial load duke parents: diff changeset	466
a61af66fc99e Initial load duke parents: diff changeset	467 // Reset the terminator, so that it may be reused again.
a61af66fc99e Initial load duke parents: diff changeset	468 // The caller is responsible for ensuring that this is done
a61af66fc99e Initial load duke parents: diff changeset	469 // in an MT-safe manner, once the previous round of use of
a61af66fc99e Initial load duke parents: diff changeset	470 // the terminator is finished.
a61af66fc99e Initial load duke parents: diff changeset	471 void reset_for_reuse();
a61af66fc99e Initial load duke parents: diff changeset	472
546 05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	473 #ifdef TRACESPINNING
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	474 static uint total_yields() { return _total_yields; }
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	475 static uint total_spins() { return _total_spins; }
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	476 static uint total_peeks() { return _total_peeks; }
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	477 static void print_termination_counts();
05c6d52fa7a9 6690928: Use spinning in combination with yields for workstealing termination. jmasa parents: 541 diff changeset	478 #endif
0 a61af66fc99e Initial load duke parents: diff changeset	479 };
a61af66fc99e Initial load duke parents: diff changeset	480
a61af66fc99e Initial load duke parents: diff changeset	481 #define SIMPLE_STACK 0
a61af66fc99e Initial load duke parents: diff changeset	482
a61af66fc99e Initial load duke parents: diff changeset	483 template<class E> inline bool GenericTaskQueue<E>::push(E t) {
a61af66fc99e Initial load duke parents: diff changeset	484 #if SIMPLE_STACK
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	485 uint localBot = _bottom;
0 a61af66fc99e Initial load duke parents: diff changeset	486 if (_bottom < max_elems()) {
a61af66fc99e Initial load duke parents: diff changeset	487 _elems[localBot] = t;
a61af66fc99e Initial load duke parents: diff changeset	488 _bottom = localBot + 1;
a61af66fc99e Initial load duke parents: diff changeset	489 return true;
a61af66fc99e Initial load duke parents: diff changeset	490 } else {
a61af66fc99e Initial load duke parents: diff changeset	491 return false;
a61af66fc99e Initial load duke parents: diff changeset	492 }
a61af66fc99e Initial load duke parents: diff changeset	493 #else
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	494 uint localBot = _bottom;
0 a61af66fc99e Initial load duke parents: diff changeset	495 assert((localBot >= 0) && (localBot < n()), "_bottom out of range.");
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	496 TAG_TYPE top = get_top();
23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	497 uint dirty_n_elems = dirty_size(localBot, top);
0 a61af66fc99e Initial load duke parents: diff changeset	498 assert((dirty_n_elems >= 0) && (dirty_n_elems < n()),
a61af66fc99e Initial load duke parents: diff changeset	499 "n_elems out of range.");
a61af66fc99e Initial load duke parents: diff changeset	500 if (dirty_n_elems < max_elems()) {
a61af66fc99e Initial load duke parents: diff changeset	501 _elems[localBot] = t;
a61af66fc99e Initial load duke parents: diff changeset	502 _bottom = increment_index(localBot);
a61af66fc99e Initial load duke parents: diff changeset	503 return true;
a61af66fc99e Initial load duke parents: diff changeset	504 } else {
a61af66fc99e Initial load duke parents: diff changeset	505 return push_slow(t, dirty_n_elems);
a61af66fc99e Initial load duke parents: diff changeset	506 }
a61af66fc99e Initial load duke parents: diff changeset	507 #endif
a61af66fc99e Initial load duke parents: diff changeset	508 }
a61af66fc99e Initial load duke parents: diff changeset	509
a61af66fc99e Initial load duke parents: diff changeset	510 template<class E> inline bool GenericTaskQueue<E>::pop_local(E& t) {
a61af66fc99e Initial load duke parents: diff changeset	511 #if SIMPLE_STACK
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	512 uint localBot = _bottom;
0 a61af66fc99e Initial load duke parents: diff changeset	513 assert(localBot > 0, "precondition.");
a61af66fc99e Initial load duke parents: diff changeset	514 localBot--;
a61af66fc99e Initial load duke parents: diff changeset	515 t = _elems[localBot];
a61af66fc99e Initial load duke parents: diff changeset	516 _bottom = localBot;
a61af66fc99e Initial load duke parents: diff changeset	517 return true;
a61af66fc99e Initial load duke parents: diff changeset	518 #else
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	519 uint localBot = _bottom;
0 a61af66fc99e Initial load duke parents: diff changeset	520 // This value cannot be n-1. That can only occur as a result of
a61af66fc99e Initial load duke parents: diff changeset	521 // the assignment to bottom in this method. If it does, this method
a61af66fc99e Initial load duke parents: diff changeset	522 // resets the size( to 0 before the next call (which is sequential,
a61af66fc99e Initial load duke parents: diff changeset	523 // since this is pop_local.)
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	524 uint dirty_n_elems = dirty_size(localBot, get_top());
0 a61af66fc99e Initial load duke parents: diff changeset	525 assert(dirty_n_elems != n() - 1, "Shouldn't be possible...");
a61af66fc99e Initial load duke parents: diff changeset	526 if (dirty_n_elems == 0) return false;
a61af66fc99e Initial load duke parents: diff changeset	527 localBot = decrement_index(localBot);
a61af66fc99e Initial load duke parents: diff changeset	528 _bottom = localBot;
a61af66fc99e Initial load duke parents: diff changeset	529 // This is necessary to prevent any read below from being reordered
a61af66fc99e Initial load duke parents: diff changeset	530 // before the store just above.
a61af66fc99e Initial load duke parents: diff changeset	531 OrderAccess::fence();
a61af66fc99e Initial load duke parents: diff changeset	532 t = _elems[localBot];
a61af66fc99e Initial load duke parents: diff changeset	533 // This is a second read of "age"; the "size()" above is the first.
a61af66fc99e Initial load duke parents: diff changeset	534 // If there's still at least one element in the queue, based on the
a61af66fc99e Initial load duke parents: diff changeset	535 // "_bottom" and "age" we've read, then there can be no interference with
a61af66fc99e Initial load duke parents: diff changeset	536 // a "pop_global" operation, and we're done.
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	537 TAG_TYPE tp = get_top(); // XXX
0 a61af66fc99e Initial load duke parents: diff changeset	538 if (size(localBot, tp) > 0) {
a61af66fc99e Initial load duke parents: diff changeset	539 assert(dirty_size(localBot, tp) != n() - 1,
a61af66fc99e Initial load duke parents: diff changeset	540 "Shouldn't be possible...");
a61af66fc99e Initial load duke parents: diff changeset	541 return true;
a61af66fc99e Initial load duke parents: diff changeset	542 } else {
a61af66fc99e Initial load duke parents: diff changeset	543 // Otherwise, the queue contained exactly one element; we take the slow
a61af66fc99e Initial load duke parents: diff changeset	544 // path.
a61af66fc99e Initial load duke parents: diff changeset	545 return pop_local_slow(localBot, get_age());
a61af66fc99e Initial load duke parents: diff changeset	546 }
a61af66fc99e Initial load duke parents: diff changeset	547 #endif
a61af66fc99e Initial load duke parents: diff changeset	548 }
a61af66fc99e Initial load duke parents: diff changeset	549
a61af66fc99e Initial load duke parents: diff changeset	550 typedef oop Task;
a61af66fc99e Initial load duke parents: diff changeset	551 typedef GenericTaskQueue<Task> OopTaskQueue;
a61af66fc99e Initial load duke parents: diff changeset	552 typedef GenericTaskQueueSet<Task> OopTaskQueueSet;
a61af66fc99e Initial load duke parents: diff changeset	553
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	554
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	555 #define COMPRESSED_OOP_MASK 1
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	556
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	557 // This is a container class for either an oop* or a narrowOop*.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	558 // Both are pushed onto a task queue and the consumer will test is_narrow()
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	559 // to determine which should be processed.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	560 class StarTask {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	561 void* _holder; // either union oop* or narrowOop*
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	562 public:
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	563 StarTask(narrowOop p) { _holder = (void )((uintptr_t)p \| COMPRESSED_OOP_MASK); }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	564 StarTask(oop p) { _holder = (void)p; }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	565 StarTask() { _holder = NULL; }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	566 operator oop() { return (oop)_holder; }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	567 operator narrowOop*() {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	568 return (narrowOop*)((uintptr_t)_holder & ~COMPRESSED_OOP_MASK);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	569 }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	570
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	571 // Operators to preserve const/volatile in assignments required by gcc
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	572 void operator=(const volatile StarTask& t) volatile { _holder = t._holder; }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	573
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	574 bool is_narrow() const {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	575 return (((uintptr_t)_holder & COMPRESSED_OOP_MASK) != 0);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	576 }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	577 };
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 0 diff changeset	578
0 a61af66fc99e Initial load duke parents: diff changeset	579 typedef GenericTaskQueue<StarTask> OopStarTaskQueue;
a61af66fc99e Initial load duke parents: diff changeset	580 typedef GenericTaskQueueSet<StarTask> OopStarTaskQueueSet;
a61af66fc99e Initial load duke parents: diff changeset	581
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	582 typedef size_t RegionTask; // index for region
81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	583 typedef GenericTaskQueue<RegionTask> RegionTaskQueue;
81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	584 typedef GenericTaskQueueSet<RegionTask> RegionTaskQueueSet;
0 a61af66fc99e Initial load duke parents: diff changeset	585
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	586 class RegionTaskQueueWithOverflow: public CHeapObj {
0 a61af66fc99e Initial load duke parents: diff changeset	587 protected:
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	588 RegionTaskQueue _region_queue;
81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	589 GrowableArray<RegionTask>* _overflow_stack;
0 a61af66fc99e Initial load duke parents: diff changeset	590
a61af66fc99e Initial load duke parents: diff changeset	591 public:
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	592 RegionTaskQueueWithOverflow() : _overflow_stack(NULL) {}
0 a61af66fc99e Initial load duke parents: diff changeset	593 // Initialize both stealable queue and overflow
a61af66fc99e Initial load duke parents: diff changeset	594 void initialize();
a61af66fc99e Initial load duke parents: diff changeset	595 // Save first to stealable queue and then to overflow
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	596 void save(RegionTask t);
0 a61af66fc99e Initial load duke parents: diff changeset	597 // Retrieve first from overflow and then from stealable queue
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	598 bool retrieve(RegionTask& region_index);
0 a61af66fc99e Initial load duke parents: diff changeset	599 // Retrieve from stealable queue
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	600 bool retrieve_from_stealable_queue(RegionTask& region_index);
0 a61af66fc99e Initial load duke parents: diff changeset	601 // Retrieve from overflow
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	602 bool retrieve_from_overflow(RegionTask& region_index);
0 a61af66fc99e Initial load duke parents: diff changeset	603 bool is_empty();
a61af66fc99e Initial load duke parents: diff changeset	604 bool stealable_is_empty();
a61af66fc99e Initial load duke parents: diff changeset	605 bool overflow_is_empty();
541 23673011938d 6787254: Work queue capacity can be increased substantially on some platforms ysr parents: 375 diff changeset	606 uint stealable_size() { return _region_queue.size(); }
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	607 RegionTaskQueue* task_queue() { return &_region_queue; }
0 a61af66fc99e Initial load duke parents: diff changeset	608 };
a61af66fc99e Initial load duke parents: diff changeset	609
375 81cd571500b0 6725697: par compact - rename class ChunkData to RegionData jcoomes parents: 356 diff changeset	610 #define USE_RegionTaskQueueWithOverflow

Mercurial > hg > truffle

annotate src/share/vm/utilities/taskqueue.hpp @ 546:05c6d52fa7a9