1 /*
 2  * Copyright (c) 2018, 2019, Red Hat, Inc. All rights reserved.
 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 4  *
 5  * This code is free software; you can redistribute it and/or modify it
 6  * under the terms of the GNU General Public License version 2 only, as
 7  * published by the Free Software Foundation.
 8  *
 9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
21  * questions.
22  *
23  */
24 
25 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHPACER_INLINE_HPP
26 #define SHARE_GC_SHENANDOAH_SHENANDOAHPACER_INLINE_HPP
27 
28 #include "gc/shenandoah/shenandoahPacer.hpp"
29 
30 #include "runtime/atomic.hpp"
31 
32 inline void ShenandoahPacer::report_mark(size_t words) {
33   report_internal(words);
34   report_progress_internal(words);
35 }
36 
37 inline void ShenandoahPacer::report_evac(size_t words) {
38   report_internal(words);
39 }
40 
41 inline void ShenandoahPacer::report_update_refs(size_t words) {
42   report_internal(words);
43 }
44 
45 inline void ShenandoahPacer::report_alloc(size_t words) {
46   report_internal(words);
47 }
48 
49 inline void ShenandoahPacer::report_internal(size_t words) {
50   assert(ShenandoahPacing, "Only be here when pacing is enabled");
51   add_budget(words);
52 }
53 
54 inline void ShenandoahPacer::report_progress_internal(size_t words) {
55   assert(ShenandoahPacing, "Only be here when pacing is enabled");
56   STATIC_ASSERT(sizeof(size_t) <= sizeof(intptr_t));
57   Atomic::add(&_progress, (intptr_t)words, memory_order_relaxed);
58 }
59 
60 inline void ShenandoahPacer::add_budget(size_t words) {
61   STATIC_ASSERT(sizeof(size_t) <= sizeof(intptr_t));
62   intptr_t inc = (intptr_t) words;
63   intptr_t new_budget = Atomic::add(&_budget, inc, memory_order_relaxed);
64 
65   // Was the budget replenished beyond zero? Then all pacing claims
66   // are satisfied, notify the waiters. Avoid taking any locks here,
67   // as it can be called from hot paths and/or while holding other locks.
68   if (new_budget >= 0 && (new_budget - inc) < 0) {
69     _need_notify_waiters.try_set();
70   }
71 }
72 
73 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHPACER_INLINE_HPP