src/share/vm/code/nmethod.cpp

@@ -460,11 +460,10 @@
 // Fill in default values for various flag fields
 void nmethod::init_defaults() {
   _state                      = alive;
   _marked_for_reclamation     = 0;
   _has_flushed_dependencies   = 0;
-  _speculatively_disconnected = 0;
   _has_unsafe_access          = 0;
   _has_method_handle_invokes  = 0;
   _lazy_critical_native       = 0;
   _has_wide_vectors           = 0;
   _marked_for_deoptimization  = 0;

@@ -479,11 +478,10 @@
   _oops_do_mark_link       = NULL;
   _jmethod_id              = NULL;
   _osr_link                = NULL;
   _scavenge_root_link      = NULL;
   _scavenge_root_state     = 0;
-  _saved_nmethod_link      = NULL;
   _compiler                = NULL;
 
 #ifdef HAVE_DTRACE_H
   _trap_offset             = 0;
 #endif // def HAVE_DTRACE_H

@@ -684,10 +682,11 @@
     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
     _osr_entry_point         = NULL;
     _exception_cache         = NULL;
     _pc_desc_cache.reset_to(NULL);
+    _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 
     code_buffer->copy_values_to(this);
     if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
       CodeCache::add_scavenge_root_nmethod(this);
       Universe::heap()->register_nmethod(this);

@@ -768,10 +767,11 @@
     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
     _osr_entry_point         = NULL;
     _exception_cache         = NULL;
     _pc_desc_cache.reset_to(NULL);
+    _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 
     code_buffer->copy_values_to(this);
     debug_only(verify_scavenge_root_oops());
     CodeCache::commit(this);
   }

@@ -840,10 +840,11 @@
     _entry_bci               = entry_bci;
     _compile_id              = compile_id;
     _comp_level              = comp_level;
     _compiler                = compiler;
     _orig_pc_offset          = orig_pc_offset;
+    _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 
     // Section offsets
     _consts_offset           = content_offset()      + code_buffer->total_offset_of(code_buffer->consts());
     _stub_offset             = content_offset()      + code_buffer->total_offset_of(code_buffer->stubs());
 

@@ -1259,11 +1260,11 @@
   // The Method* is gone at this point
   assert(_method == NULL, "Tautology");
 
   set_osr_link(NULL);
   //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
-  NMethodSweeper::notify(this);
+  NMethodSweeper::notify();
 }
 
 void nmethod::invalidate_osr_method() {
   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
   // Remove from list of active nmethods

@@ -1349,10 +1350,18 @@
     // This nmethod may have already been unloaded during a full GC.
     if ((state == zombie) && !is_unloaded()) {
       nmethod_needs_unregister = true;
     }
 
+    // Must happen before state change. Otherwise we have a race condition in
+    // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
+    // transition its state from 'not_entrant' to 'zombie' without having to wait
+    // for stack scanning.
+    if (state == not_entrant) {
+      mark_as_seen_on_stack();
+    }
+
     // Change state
     _state = state;
 
     // Log the transition once
     log_state_change();

@@ -1367,15 +1376,10 @@
     if (method() != NULL && (method()->code() == this ||
                              method()->from_compiled_entry() == verified_entry_point())) {
       HandleMark hm;
       method()->clear_code();
     }
-
-    if (state == not_entrant) {
-      mark_as_seen_on_stack();
-    }
-
   } // leave critical region under Patching_lock
 
   // When the nmethod becomes zombie it is no longer alive so the
   // dependencies must be flushed.  nmethods in the not_entrant
   // state will be flushed later when the transition to zombie

@@ -1414,11 +1418,11 @@
   if (TraceCreateZombies) {
     tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
   }
 
   // Make sweeper aware that there is a zombie method that needs to be removed
-  NMethodSweeper::notify(this);
+  NMethodSweeper::notify();
 
   return true;
 }
 
 void nmethod::flush() {

@@ -1449,14 +1453,10 @@
 
   if (on_scavenge_root_list()) {
     CodeCache::drop_scavenge_root_nmethod(this);
   }
 
-  if (is_speculatively_disconnected()) {
-    CodeCache::remove_saved_code(this);
-  }
-
 #ifdef SHARK
   ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
 #endif // SHARK
 
   ((CodeBlob*)(this))->flush();