jfrEpochSynchronization.cpp

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#include "precompiled.hpp"
#include "jfr/recorder/checkpoint/types/traceid/jfrTraceIdEpoch.hpp"
#include "jfr/support/jfrEpochSynchronization.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/thread.inline.hpp"

JfrEpochSynchronization::JfrEpochSynchronization() {
  if (JfrTraceIdEpoch::is_synchronizing()) {
    // only at a safepoint
    JavaThread* const jt = JavaThread::current();
    assert(jt->thread_state() == _thread_in_native, "invariant");
    // use ordinary transition to have the thread block and await the new epoch
    ThreadInVMfromNative transition(jt);
  }
}