src/share/vm/runtime/biasedLocking.cpp

rev 13259 : 8184181: Use oopDesc::cas_set_mark() instead of raw CAS when accessing oop header
Reviewed-by: dcubed, kbarret

@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 2005, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.

@@ -577,11 +577,11 @@
     // compare-and-exchange an unbiased header into the mark word of
     // the object, meaning that no other thread has raced to acquire
     // the bias of the object.
     markOop biased_value       = mark;
     markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age());
-    markOop res_mark = (markOop) Atomic::cmpxchg_ptr(unbiased_prototype, obj->mark_addr(), mark);
+    markOop res_mark = obj->cas_set_mark(unbiased_prototype, mark);
     if (res_mark == biased_value) {
       return BIAS_REVOKED;
     }
   } else if (mark->has_bias_pattern()) {
     Klass* k = obj->klass();

@@ -592,11 +592,11 @@
       // heuristics at this point so simply update the header with a
       // CAS. If we fail this race, the object's bias has been revoked
       // by another thread so we simply return and let the caller deal
       // with it.
       markOop biased_value       = mark;
-      markOop res_mark = (markOop) Atomic::cmpxchg_ptr(prototype_header, obj->mark_addr(), mark);
+      markOop res_mark = obj->cas_set_mark(prototype_header, mark);
       assert(!(*(obj->mark_addr()))->has_bias_pattern(), "even if we raced, should still be revoked");
       return BIAS_REVOKED;
     } else if (prototype_header->bias_epoch() != mark->bias_epoch()) {
       // The epoch of this biasing has expired indicating that the
       // object is effectively unbiased. Depending on whether we need

@@ -607,18 +607,18 @@
       // needing to revoke biases.
       if (attempt_rebias) {
         assert(THREAD->is_Java_thread(), "");
         markOop biased_value       = mark;
         markOop rebiased_prototype = markOopDesc::encode((JavaThread*) THREAD, mark->age(), prototype_header->bias_epoch());
-        markOop res_mark = (markOop) Atomic::cmpxchg_ptr(rebiased_prototype, obj->mark_addr(), mark);
+        markOop res_mark = obj->cas_set_mark(rebiased_prototype, mark);
         if (res_mark == biased_value) {
           return BIAS_REVOKED_AND_REBIASED;
         }
       } else {
         markOop biased_value       = mark;
         markOop unbiased_prototype = markOopDesc::prototype()->set_age(mark->age());
-        markOop res_mark = (markOop) Atomic::cmpxchg_ptr(unbiased_prototype, obj->mark_addr(), mark);
+        markOop res_mark = obj->cas_set_mark(unbiased_prototype, mark);
         if (res_mark == biased_value) {
           return BIAS_REVOKED;
         }
       }
     }