8205725: Update the JVMTI Spec for Heap Sampling
Summary: Update the JVMTI Spec for Heap Sampling
Reviewed-by: amenkov, sspitsyn
Contributed-by: jcbeyler@google.com
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#ifndef SHARE_VM_RUNTIME_THREADSMR_INLINE_HPP
#define SHARE_VM_RUNTIME_THREADSMR_INLINE_HPP
#include "runtime/atomic.hpp"
#include "runtime/prefetch.inline.hpp"
#include "runtime/thread.inline.hpp"
#include "runtime/threadSMR.hpp"
// Devirtualize known thread closure types.
template <class T>
inline void ThreadsList::threads_do_dispatch(T *cl, JavaThread *const thread) const {
cl->T::do_thread(thread);
}
template <>
inline void ThreadsList::threads_do_dispatch<ThreadClosure>(ThreadClosure *cl, JavaThread *const thread) const {
cl->do_thread(thread);
}
template <class T>
inline void ThreadsList::threads_do(T *cl) const {
const intx scan_interval = PrefetchScanIntervalInBytes;
JavaThread *const *const end = _threads + _length;
for (JavaThread *const *current_p = _threads; current_p != end; current_p++) {
Prefetch::read((void*)current_p, scan_interval);
JavaThread *const current = *current_p;
threads_do_dispatch(cl, current);
}
}
// These three inlines are private to ThreadsSMRSupport, but
// they are called by public inline update_tlh_stats() below:
inline void ThreadsSMRSupport::add_tlh_times(uint add_value) {
Atomic::add(add_value, &_tlh_times);
}
inline void ThreadsSMRSupport::inc_tlh_cnt() {
Atomic::inc(&_tlh_cnt);
}
inline void ThreadsSMRSupport::update_tlh_time_max(uint new_value) {
while (true) {
uint cur_value = _tlh_time_max;
if (new_value <= cur_value) {
// No need to update max value so we're done.
break;
}
if (Atomic::cmpxchg(new_value, &_tlh_time_max, cur_value) == cur_value) {
// Updated max value so we're done. Otherwise try it all again.
break;
}
}
}
inline ThreadsList* ThreadsSMRSupport::get_java_thread_list() {
return (ThreadsList*)OrderAccess::load_acquire(&_java_thread_list);
}
inline bool ThreadsSMRSupport::is_a_protected_JavaThread_with_lock(JavaThread *thread) {
MutexLockerEx ml(Threads_lock->owned_by_self() ? NULL : Threads_lock);
return is_a_protected_JavaThread(thread);
}
inline void ThreadsSMRSupport::update_tlh_stats(uint millis) {
ThreadsSMRSupport::inc_tlh_cnt();
ThreadsSMRSupport::add_tlh_times(millis);
ThreadsSMRSupport::update_tlh_time_max(millis);
}
#endif // SHARE_VM_RUNTIME_THREADSMR_INLINE_HPP