*** old/src/share/vm/oops/instanceKlass.cpp	Tue Oct 14 09:38:29 2014
--- new/src/share/vm/oops/instanceKlass.cpp	Tue Oct 14 09:38:29 2014

*** 2778,2799 ****
--- 2778,2799 ----
  
  // On-stack replacement stuff
  void InstanceKlass::add_osr_nmethod(nmethod* n) {
    // only one compilation can be active
    NEEDS_CLEANUP
+   {
      // This is a short non-blocking critical region, so the no safepoint check is ok.
!   OsrList_lock->lock_without_safepoint_check();
!     MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
      assert(n->is_osr_method(), "wrong kind of nmethod");
      n->set_osr_link(osr_nmethods_head());
      set_osr_nmethods_head(n);
      // Raise the highest osr level if necessary
      if (TieredCompilation) {
        Method* m = n->method();
        m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
      }
    // Remember to unlock again
    OsrList_lock->unlock();
+   }
  
    // Get rid of the osr methods for the same bci that have lower levels.
    if (TieredCompilation) {
      for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
        nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);

*** 2805,2815 ****
--- 2805,2815 ----
  }
  
  
  void InstanceKlass::remove_osr_nmethod(nmethod* n) {
    // This is a short non-blocking critical region, so the no safepoint check is ok.
!   OsrList_lock->lock_without_safepoint_check();
!   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
    assert(n->is_osr_method(), "wrong kind of nmethod");
    nmethod* last = NULL;
    nmethod* cur  = osr_nmethods_head();
    int max_level = CompLevel_none;  // Find the max comp level excluding n
    Method* m = n->method();

*** 2842,2858 ****
--- 2842,2856 ----
        }
        cur = cur->osr_link();
      }
      m->set_highest_osr_comp_level(max_level);
    }
    // Remember to unlock again
    OsrList_lock->unlock();
  }
  
  nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
    // This is a short non-blocking critical region, so the no safepoint check is ok.
!   OsrList_lock->lock_without_safepoint_check();
!   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
    nmethod* osr = osr_nmethods_head();
    nmethod* best = NULL;
    while (osr != NULL) {
      assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
      // There can be a time when a c1 osr method exists but we are waiting

*** 2864,2890 ****
--- 2862,2885 ----
      if (osr->method() == m &&
          (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
        if (match_level) {
          if (osr->comp_level() == comp_level) {
            // Found a match - return it.
            OsrList_lock->unlock();
            return osr;
          }
        } else {
          if (best == NULL || (osr->comp_level() > best->comp_level())) {
            if (osr->comp_level() == CompLevel_highest_tier) {
              // Found the best possible - return it.
              OsrList_lock->unlock();
              return osr;
            }
            best = osr;
          }
        }
      }
      osr = osr->osr_link();
    }
    OsrList_lock->unlock();
    if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
      return best;
    }
    return NULL;
  }