8186837: Memory ordering nmethod, _state and _stack_traversal_mark
Reviewed-by: dholmes, rkennke
--- a/hotspot/src/share/vm/code/nmethod.cpp Wed Aug 30 19:18:22 2017 -0400
+++ b/hotspot/src/share/vm/code/nmethod.cpp Thu Aug 31 08:18:47 2017 +0200
@@ -1220,7 +1220,7 @@
// for stack scanning.
if (state == not_entrant) {
mark_as_seen_on_stack();
- OrderAccess::storestore();
+ OrderAccess::storestore(); // _stack_traversal_mark and _state
}
// Change state
--- a/hotspot/src/share/vm/code/nmethod.hpp Wed Aug 30 19:18:22 2017 -0400
+++ b/hotspot/src/share/vm/code/nmethod.hpp Thu Aug 31 08:18:47 2017 +0200
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 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
@@ -136,7 +136,7 @@
// stack. An not_entrant method can be removed when there are no
// more activations, i.e., when the _stack_traversal_mark is less than
// current sweep traversal index.
- volatile jlong _stack_traversal_mark;
+ volatile long _stack_traversal_mark;
// The _hotness_counter indicates the hotness of a method. The higher
// the value the hotter the method. The hotness counter of a nmethod is
@@ -396,8 +396,8 @@
public:
// Sweeper support
- jlong stack_traversal_mark() { return OrderAccess::load_acquire(&_stack_traversal_mark); }
- void set_stack_traversal_mark(jlong l) { OrderAccess::release_store(&_stack_traversal_mark, l); }
+ long stack_traversal_mark() { return _stack_traversal_mark; }
+ void set_stack_traversal_mark(long l) { _stack_traversal_mark = l; }
// implicit exceptions support
address continuation_for_implicit_exception(address pc);
--- a/hotspot/src/share/vm/runtime/sweeper.cpp Wed Aug 30 19:18:22 2017 -0400
+++ b/hotspot/src/share/vm/runtime/sweeper.cpp Thu Aug 31 08:18:47 2017 +0200
@@ -53,7 +53,7 @@
public:
int traversal;
int compile_id;
- jlong traversal_mark;
+ long traversal_mark;
int state;
const char* kind;
address vep;
@@ -62,7 +62,7 @@
void print() {
tty->print_cr("traversal = %d compile_id = %d %s uep = " PTR_FORMAT " vep = "
- PTR_FORMAT " state = %d traversal_mark "JLONG_FORMAT" line = %d",
+ PTR_FORMAT " state = %d traversal_mark %ld line = %d",
traversal,
compile_id,
kind == NULL ? "" : kind,
@@ -629,6 +629,7 @@
} else if (cm->is_not_entrant()) {
// If there are no current activations of this method on the
// stack we can safely convert it to a zombie method
+ OrderAccess::loadload(); // _stack_traversal_mark and _state
if (cm->can_convert_to_zombie()) {
// Clear ICStubs to prevent back patching stubs of zombie or flushed
// nmethods during the next safepoint (see ICStub::finalize).
--- a/hotspot/src/share/vm/runtime/vmStructs.cpp Wed Aug 30 19:18:22 2017 -0400
+++ b/hotspot/src/share/vm/runtime/vmStructs.cpp Thu Aug 31 08:18:47 2017 +0200
@@ -841,7 +841,7 @@
nonstatic_field(nmethod, _verified_entry_point, address) \
nonstatic_field(nmethod, _osr_entry_point, address) \
volatile_nonstatic_field(nmethod, _lock_count, jint) \
- volatile_nonstatic_field(nmethod, _stack_traversal_mark, jlong) \
+ volatile_nonstatic_field(nmethod, _stack_traversal_mark, long) \
nonstatic_field(nmethod, _compile_id, int) \
nonstatic_field(nmethod, _comp_level, int) \
\