1 /*
   2  * Copyright (c) 2019, Red Hat, Inc. All rights reserved.
   3  *
   4  * This code is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This code is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * version 2 for more details (a copy is included in the LICENSE file that
  12  * accompanied this code).
  13  *
  14  * You should have received a copy of the GNU General Public License version
  15  * 2 along with this work; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  19  * or visit www.oracle.com if you need additional information or have any
  20  * questions.
  21  *
  22  */
  23 
  24 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_INLINE_HPP
  25 #define SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_INLINE_HPP
  26 
  27 #include "gc/shenandoah/shenandoahHeuristics.hpp"
  28 #include "gc/shenandoah/shenandoahRootProcessor.hpp"
  29 #include "gc/shenandoah/shenandoahTimingTracker.hpp"
  30 #include "gc/shenandoah/shenandoahUtils.hpp"
  31 #include "memory/resourceArea.hpp"
  32 
  33 template <typename IsAlive, typename KeepAlive>
  34 void ShenandoahWeakRoots::oops_do(IsAlive* is_alive, KeepAlive* keep_alive, uint worker_id) {
  35   _task.work<IsAlive, KeepAlive>(worker_id, is_alive, keep_alive);
  36 }
  37 
  38 template <typename ITR>
  39 ShenandoahCodeCacheRoots<ITR>::ShenandoahCodeCacheRoots() {
  40   nmethod::oops_do_marking_prologue();
  41 }
  42 
  43 template <typename ITR>
  44 void ShenandoahCodeCacheRoots<ITR>::code_blobs_do(CodeBlobClosure* blob_cl, uint worker_id) {
  45   ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
  46   ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::CodeCacheRoots, worker_id);
  47   _coderoots_iterator.possibly_parallel_blobs_do(blob_cl);
  48 }
  49 
  50 template <typename ITR>
  51 ShenandoahCodeCacheRoots<ITR>::~ShenandoahCodeCacheRoots() {
  52   nmethod::oops_do_marking_epilogue();
  53 }
  54 
  55 class ShenandoahParallelOopsDoThreadClosure : public ThreadClosure {
  56 private:
  57   OopClosure* _f;
  58   CodeBlobClosure* _cf;
  59   ThreadClosure* _thread_cl;
  60 public:
  61   ShenandoahParallelOopsDoThreadClosure(OopClosure* f, CodeBlobClosure* cf, ThreadClosure* thread_cl) :
  62     _f(f), _cf(cf), _thread_cl(thread_cl) {}
  63 
  64   void do_thread(Thread* t) {
  65     if (_thread_cl != NULL) {
  66       _thread_cl->do_thread(t);
  67     }
  68     t->oops_do(_f, _cf);
  69   }
  70 };
  71 
  72 template <typename ITR>
  73 ShenandoahRootScanner<ITR>::ShenandoahRootScanner(uint n_workers, ShenandoahPhaseTimings::Phase phase) :
  74   ShenandoahRootProcessor(phase),
  75   _thread_roots(n_workers > 1) {
  76 }
  77 
  78 template <typename ITR>
  79 void ShenandoahRootScanner<ITR>::roots_do(uint worker_id, OopClosure* oops) {
  80   CLDToOopClosure clds_cl(oops, ClassLoaderData::_claim_strong);
  81   MarkingCodeBlobClosure blobs_cl(oops, !CodeBlobToOopClosure::FixRelocations);
  82   roots_do(worker_id, oops, &clds_cl, &blobs_cl);
  83 }
  84 
  85 template <typename ITR>
  86 void ShenandoahRootScanner<ITR>::strong_roots_do(uint worker_id, OopClosure* oops) {
  87   CLDToOopClosure clds_cl(oops, ClassLoaderData::_claim_strong);
  88   MarkingCodeBlobClosure blobs_cl(oops, !CodeBlobToOopClosure::FixRelocations);
  89   strong_roots_do(worker_id, oops, &clds_cl, &blobs_cl);
  90 }
  91 
  92 template <typename ITR>
  93 void ShenandoahRootScanner<ITR>::roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure *tc) {
  94   assert(!ShenandoahSafepoint::is_at_shenandoah_safepoint() ||
  95          !ShenandoahHeap::heap()->unload_classes() ||
  96           ShenandoahHeap::heap()->heuristics()->can_do_traversal_gc(),
  97           "Expect class unloading or traversal when Shenandoah cycle is running");
  98   ShenandoahParallelOopsDoThreadClosure tc_cl(oops, code, tc);
  99   ResourceMark rm;
 100 
 101   _serial_roots.oops_do(oops, worker_id);
 102   _cld_roots.clds_do(clds, clds, worker_id);
 103   _thread_roots.threads_do(&tc_cl, worker_id);
 104 
 105   // With ShenandoahConcurrentScanCodeRoots, we avoid scanning the entire code cache here,
 106   // and instead do that in concurrent phase under the relevant lock. This saves init mark
 107   // pause time.
 108   if (code != NULL && !ShenandoahConcurrentScanCodeRoots) {
 109     _code_roots.code_blobs_do(code, worker_id);
 110   }
 111 }
 112 
 113 template <typename ITR>
 114 void ShenandoahRootScanner<ITR>::strong_roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure* tc) {
 115   assert(ShenandoahHeap::heap()->unload_classes(), "Should be used during class unloading");
 116   ShenandoahParallelOopsDoThreadClosure tc_cl(oops, code, tc);
 117   ResourceMark rm;
 118 
 119   _serial_roots.oops_do(oops, worker_id);
 120   _cld_roots.clds_do(clds, NULL, worker_id);
 121   _thread_roots.threads_do(&tc_cl, worker_id);
 122 }
 123 
 124 template <typename IsAlive, typename KeepAlive>
 125 void ShenandoahRootUpdater::roots_do(uint worker_id, IsAlive* is_alive, KeepAlive* keep_alive) {
 126   CodeBlobToOopClosure update_blobs(keep_alive, CodeBlobToOopClosure::FixRelocations);
 127   CLDToOopClosure clds(keep_alive, ClassLoaderData::_claim_strong);
 128   CLDToOopClosure* weak_clds = ShenandoahHeap::heap()->unload_classes() ? NULL : &clds;
 129 
 130   _serial_roots.oops_do(keep_alive, worker_id);
 131 
 132   _thread_roots.oops_do(keep_alive, NULL, worker_id);
 133   _cld_roots.clds_do(&clds, weak_clds, worker_id);
 134 
 135   if(_update_code_cache) {
 136     _code_roots.code_blobs_do(&update_blobs, worker_id);
 137   }
 138 
 139   _weak_roots.oops_do<IsAlive, KeepAlive>(is_alive, keep_alive, worker_id);
 140   _dedup_roots.oops_do(is_alive, keep_alive, worker_id);
 141 }
 142 
 143 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_INLINE_HPP