src/hotspot/os/bsd/os_bsd.cpp

*** 928,938 ****
    const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
    const uint64_t prev = Bsd::_max_abstime;
    if (now <= prev) {
      return prev;   // same or retrograde time;
    }
!   const uint64_t obsv = Atomic::cmpxchg(now, &Bsd::_max_abstime, prev);
    assert(obsv >= prev, "invariant");   // Monotonicity
    // If the CAS succeeded then we're done and return "now".
    // If the CAS failed and the observed value "obsv" is >= now then
    // we should return "obsv".  If the CAS failed and now > obsv > prv then
    // some other thread raced this thread and installed a new value, in which case
--- 928,938 ----
    const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
    const uint64_t prev = Bsd::_max_abstime;
    if (now <= prev) {
      return prev;   // same or retrograde time;
    }
!   const uint64_t obsv = Atomic::cmpxchg(&Bsd::_max_abstime, prev, now);
    assert(obsv >= prev, "invariant");   // Monotonicity
    // If the CAS succeeded then we're done and return "now".
    // If the CAS failed and the observed value "obsv" is >= now then
    // we should return "obsv".  If the CAS failed and now > obsv > prv then
    // some other thread raced this thread and installed a new value, in which case
*** 1831,1841 ****
  
  static int check_pending_signals() {
    for (;;) {
      for (int i = 0; i < NSIG + 1; i++) {
        jint n = pending_signals[i];
!       if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
          return i;
        }
      }
      JavaThread *thread = JavaThread::current();
      ThreadBlockInVM tbivm(thread);
--- 1831,1841 ----
  
  static int check_pending_signals() {
    for (;;) {
      for (int i = 0; i < NSIG + 1; i++) {
        jint n = pending_signals[i];
!       if (n > 0 && n == Atomic::cmpxchg(&pending_signals[i], n, n - 1)) {
          return i;
        }
      }
      JavaThread *thread = JavaThread::current();
      ThreadBlockInVM tbivm(thread);
*** 1892,1902 ****
    if (!UseOprofile) {
      return;
    }
  
    char buf[PATH_MAX + 1];
!   int num = Atomic::add(1, &cnt);
  
    snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
             os::get_temp_directory(), os::current_process_id(), num);
    unlink(buf);
  
--- 1892,1902 ----
    if (!UseOprofile) {
      return;
    }
  
    char buf[PATH_MAX + 1];
!   int num = Atomic::add(&cnt, 1);
  
    snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
             os::get_temp_directory(), os::current_process_id(), num);
    unlink(buf);
  
*** 3235,3245 ****
  
      for (uint i = 0; i < max_apic_ids; ++i) {
        mapping[i] = -1;
      }
  
!     if (!Atomic::replace_if_null(mapping, &apic_to_processor_mapping)) {
        FREE_C_HEAP_ARRAY(int, mapping);
        mapping = Atomic::load_acquire(&apic_to_processor_mapping);
      }
    }
  
--- 3235,3245 ----
  
      for (uint i = 0; i < max_apic_ids; ++i) {
        mapping[i] = -1;
      }
  
!     if (!Atomic::replace_if_null(&apic_to_processor_mapping, mapping)) {
        FREE_C_HEAP_ARRAY(int, mapping);
        mapping = Atomic::load_acquire(&apic_to_processor_mapping);
      }
    }
  
*** 3261,3272 ****
  
    uint apic_id = edx;
    int processor_id = Atomic::load(&mapping[apic_id]);
  
    while (processor_id < 0) {
!     if (Atomic::cmpxchg(-2, &mapping[apic_id], -1)) {
!       Atomic::store(Atomic::add(1, &next_processor_id) - 1, &mapping[apic_id]);
      }
      processor_id = Atomic::load(&mapping[apic_id]);
    }
  
    return (uint)processor_id;
--- 3261,3272 ----
  
    uint apic_id = edx;
    int processor_id = Atomic::load(&mapping[apic_id]);
  
    while (processor_id < 0) {
!     if (Atomic::cmpxchg(&mapping[apic_id], -1, -2)) {
!       Atomic::store(&mapping[apic_id], Atomic::add(&next_processor_id, 1) - 1);
      }
      processor_id = Atomic::load(&mapping[apic_id]);
    }
  
    return (uint)processor_id;