src/hotspot/share/gc/shared/barrierSet.cpp
author kbarrett
Tue, 11 Dec 2018 18:00:17 -0500
changeset 52955 f0f3dc30e3bb
parent 51600 56309b1b9d9b
permissions -rw-r--r--
8215097: Do not create NonJavaThreads before BarrierSet Summary: G1 and CMS delay worker thread creation until BarrierSet exists. Reviewed-by: dholmes, tschatzl

/*
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include "precompiled.hpp"
#include "gc/shared/barrierSet.hpp"
#include "gc/shared/barrierSetAssembler.hpp"
#include "runtime/thread.hpp"
#include "utilities/debug.hpp"
#include "utilities/macros.hpp"

BarrierSet* BarrierSet::_barrier_set = NULL;

void BarrierSet::set_barrier_set(BarrierSet* barrier_set) {
  assert(_barrier_set == NULL, "Already initialized");
  _barrier_set = barrier_set;

  // Notify barrier set of the current (main) thread.  Normally the
  // Thread constructor deals with this, but the main thread is
  // created before we get here.  Verify it isn't yet on the thread
  // list, else we'd also need to call BarrierSet::on_thread_attach.
  // This is the only thread that can exist at this point; the Thread
  // constructor objects to other threads being created before the
  // barrier set is available.
  assert(Thread::current()->is_Java_thread(),
         "Expected main thread to be a JavaThread");
  assert(!JavaThread::current()->on_thread_list(),
         "Main thread already on thread list.");
  _barrier_set->on_thread_create(Thread::current());
}

// Called from init.cpp
void gc_barrier_stubs_init() {
  BarrierSet* bs = BarrierSet::barrier_set();
#ifndef ZERO
  BarrierSetAssembler* bs_assembler = bs->barrier_set_assembler();
  bs_assembler->barrier_stubs_init();
#endif
}