# HG changeset patch
# Parent 5b84039ca7399dbc4ae8b1467fe6048b4e33f93b
8023037: Race between ciEnv::register_method and nmethod::make_not_entrant_or_zombie
Reviewed-by: ?

diff --git a/src/share/vm/ci/ciEnv.cpp b/src/share/vm/ci/ciEnv.cpp
--- a/src/share/vm/ci/ciEnv.cpp
+++ b/src/share/vm/ci/ciEnv.cpp
@@ -1020,48 +1020,54 @@
         CompileBroker::handle_full_code_cache();
       }
     } else {
+      // Need to coordinate method registration with the sweeper thread.
+      nmethodLocker nml(nm);
+
       nm->set_has_unsafe_access(has_unsafe_access);
       nm->set_has_wide_vectors(has_wide_vectors);
 
-      // Record successful registration.
-      // (Put nm into the task handle *before* publishing to the Java heap.)
-      if (task() != NULL)  task()->set_code(nm);
+      // nmethod could be marked as non-entrant by the sweeper already.
+      // Don't install it then.
+      if (nm->is_in_use()) {
+        // Record successful registration.
+        // (Put nm into the task handle *before* publishing to the Java heap.)
+        if (task() != NULL)  task()->set_code(nm);
 
-      if (entry_bci == InvocationEntryBci) {
-        if (TieredCompilation) {
-          // If there is an old version we're done with it
-          nmethod* old = method->code();
-          if (TraceMethodReplacement && old != NULL) {
+        if (entry_bci == InvocationEntryBci) {
+          if (TieredCompilation) {
+            // If there is an old version we're done with it
+            nmethod* old = method->code();
+            if (TraceMethodReplacement && old != NULL) {
+              ResourceMark rm;
+              char *method_name = method->name_and_sig_as_C_string();
+              tty->print_cr("Replacing method %s", method_name);
+            }
+            if (old != NULL ) {
+              old->make_not_entrant();
+            }
+          }
+          if (TraceNMethodInstalls) {
             ResourceMark rm;
             char *method_name = method->name_and_sig_as_C_string();
-            tty->print_cr("Replacing method %s", method_name);
+            ttyLocker ttyl;
+            tty->print_cr("Installing method (%d) %s ",
+                          comp_level,
+                          method_name);
           }
-          if (old != NULL ) {
-            old->make_not_entrant();
+          // Allow the code to be executed
+          method->set_code(method, nm);
+        } else {
+          if (TraceNMethodInstalls ) {
+            ResourceMark rm;
+            char *method_name = method->name_and_sig_as_C_string();
+            ttyLocker ttyl;
+            tty->print_cr("Installing osr method (%d) %s @ %d",
+                          comp_level,
+                          method_name,
+                          entry_bci);
           }
+          method->method_holder()->add_osr_nmethod(nm);
         }
-        if (TraceNMethodInstalls ) {
-          ResourceMark rm;
-          char *method_name = method->name_and_sig_as_C_string();
-          ttyLocker ttyl;
-          tty->print_cr("Installing method (%d) %s ",
-                        comp_level,
-                        method_name);
-        }
-        // Allow the code to be executed
-        method->set_code(method, nm);
-      } else {
-        if (TraceNMethodInstalls ) {
-          ResourceMark rm;
-          char *method_name = method->name_and_sig_as_C_string();
-          ttyLocker ttyl;
-          tty->print_cr("Installing osr method (%d) %s @ %d",
-                        comp_level,
-                        method_name,
-                        entry_bci);
-        }
-        method->method_holder()->add_osr_nmethod(nm);
-
       }
     }
   }
@@ -1069,7 +1075,6 @@
   if (nm != NULL) {
     nm->post_compiled_method_load_event();
   }
-
 }