--- a/hotspot/src/share/vm/oops/instanceKlass.cpp Tue Oct 20 11:17:19 2015 -0400
+++ b/hotspot/src/share/vm/oops/instanceKlass.cpp Tue Oct 13 10:06:46 2015 +0200
@@ -1907,18 +1907,33 @@
// Decrement count of the nmethod in the dependency list and remove
// the bucket completely when the count goes to 0. This method must
// find a corresponding bucket otherwise there's a bug in the
-// recording of dependencies. Returns true if the bucket is ready for reclamation.
-//
-bool nmethodBucket::remove_dependent_nmethod(nmethodBucket* deps, nmethod* nm) {
+// recording of dependencies. Returns true if the bucket was deleted,
+// or marked ready for reclaimation.
+bool nmethodBucket::remove_dependent_nmethod(nmethodBucket** deps, nmethod* nm, bool delete_immediately) {
assert_locked_or_safepoint(CodeCache_lock);
- for (nmethodBucket* b = deps; b != NULL; b = b->next()) {
+ nmethodBucket* first = *deps;
+ nmethodBucket* last = NULL;
+
+ for (nmethodBucket* b = first; b != NULL; b = b->next()) {
if (nm == b->get_nmethod()) {
int val = b->decrement();
guarantee(val >= 0, "Underflow: %d", val);
- return (val == 0);
+ if (val == 0) {
+ if (delete_immediately) {
+ if (last == NULL) {
+ *deps = b->next();
+ } else {
+ last->set_next(b->next());
+ }
+ delete b;
+ }
+ }
+ return true;
}
+ last = b;
}
+
#ifdef ASSERT
tty->print_raw_cr("### can't find dependent nmethod");
nm->print();
@@ -1927,6 +1942,12 @@
return false;
}
+// Convenience overload, for callers that don't want to delete the nmethodBucket entry.
+bool nmethodBucket::remove_dependent_nmethod(nmethodBucket* deps, nmethod* nm) {
+ nmethodBucket** deps_addr = &deps;
+ return remove_dependent_nmethod(deps_addr, nm, false /* Don't delete */);
+}
+
//
// Reclaim all unused buckets. Returns new head of the list.
//
@@ -2013,10 +2034,10 @@
_dependencies = nmethodBucket::add_dependent_nmethod(_dependencies, nm);
}
-void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
+void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
assert_locked_or_safepoint(CodeCache_lock);
- if (nmethodBucket::remove_dependent_nmethod(_dependencies, nm)) {
+ if (nmethodBucket::remove_dependent_nmethod(&_dependencies, nm, delete_immediately)) {
set_has_unloaded_dependent(true);
}
}
@@ -2031,6 +2052,13 @@
}
#endif //PRODUCT
+void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
+ clean_implementors_list(is_alive);
+ clean_method_data(is_alive);
+
+ clean_dependent_nmethods();
+}
+
void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
if (is_interface()) {
@@ -3546,3 +3574,199 @@
unsigned char * InstanceKlass::get_cached_class_file_bytes() {
return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
}
+
+
+/////////////// Unit tests ///////////////
+
+#ifndef PRODUCT
+
+class TestNmethodBucketContext {
+ public:
+ nmethod* _nmethodLast;
+ nmethod* _nmethodMiddle;
+ nmethod* _nmethodFirst;
+
+ nmethodBucket* _bucketLast;
+ nmethodBucket* _bucketMiddle;
+ nmethodBucket* _bucketFirst;
+
+ nmethodBucket* _bucketList;
+
+ TestNmethodBucketContext() {
+ CodeCache_lock->lock_without_safepoint_check();
+
+ _nmethodLast = reinterpret_cast<nmethod*>(0x8 * 0);
+ _nmethodMiddle = reinterpret_cast<nmethod*>(0x8 * 1);
+ _nmethodFirst = reinterpret_cast<nmethod*>(0x8 * 2);
+
+ _bucketLast = new nmethodBucket(_nmethodLast, NULL);
+ _bucketMiddle = new nmethodBucket(_nmethodMiddle, _bucketLast);
+ _bucketFirst = new nmethodBucket(_nmethodFirst, _bucketMiddle);
+
+ _bucketList = _bucketFirst;
+ }
+
+ ~TestNmethodBucketContext() {
+ delete _bucketLast;
+ delete _bucketMiddle;
+ delete _bucketFirst;
+
+ CodeCache_lock->unlock();
+ }
+};
+
+class TestNmethodBucket {
+ public:
+ static void testRemoveDependentNmethodFirstDeleteImmediately() {
+ TestNmethodBucketContext c;
+
+ nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodFirst, true /* delete */);
+
+ assert(c._bucketList == c._bucketMiddle, "check");
+ assert(c._bucketList->next() == c._bucketLast, "check");
+ assert(c._bucketList->next()->next() == NULL, "check");
+
+ // Cleanup before context is deleted.
+ c._bucketFirst = NULL;
+ }
+
+ static void testRemoveDependentNmethodMiddleDeleteImmediately() {
+ TestNmethodBucketContext c;
+
+ nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodMiddle, true /* delete */);
+
+ assert(c._bucketList == c._bucketFirst, "check");
+ assert(c._bucketList->next() == c._bucketLast, "check");
+ assert(c._bucketList->next()->next() == NULL, "check");
+
+ // Cleanup before context is deleted.
+ c._bucketMiddle = NULL;
+ }
+
+ static void testRemoveDependentNmethodLastDeleteImmediately() {
+ TestNmethodBucketContext c;
+
+ nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodLast, true /* delete */);
+
+ assert(c._bucketList == c._bucketFirst, "check");
+ assert(c._bucketList->next() == c._bucketMiddle, "check");
+ assert(c._bucketList->next()->next() == NULL, "check");
+
+ // Cleanup before context is deleted.
+ c._bucketLast = NULL;
+ }
+
+ static void testRemoveDependentNmethodFirstDeleteDeferred() {
+ TestNmethodBucketContext c;
+
+ nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodFirst, false /* delete */);
+
+ assert(c._bucketList == c._bucketFirst, "check");
+ assert(c._bucketList->next() == c._bucketMiddle, "check");
+ assert(c._bucketList->next()->next() == c._bucketLast, "check");
+ assert(c._bucketList->next()->next()->next() == NULL, "check");
+
+ assert(c._bucketFirst->count() == 0, "check");
+ assert(c._bucketMiddle->count() == 1, "check");
+ assert(c._bucketLast->count() == 1, "check");
+ }
+
+ static void testRemoveDependentNmethodMiddleDeleteDeferred() {
+ TestNmethodBucketContext c;
+
+ nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodMiddle, false /* delete */);
+
+ assert(c._bucketList == c._bucketFirst, "check");
+ assert(c._bucketList->next() == c._bucketMiddle, "check");
+ assert(c._bucketList->next()->next() == c._bucketLast, "check");
+ assert(c._bucketList->next()->next()->next() == NULL, "check");
+
+ assert(c._bucketFirst->count() == 1, "check");
+ assert(c._bucketMiddle->count() == 0, "check");
+ assert(c._bucketLast->count() == 1, "check");
+ }
+
+ static void testRemoveDependentNmethodLastDeleteDeferred() {
+ TestNmethodBucketContext c;
+
+ nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodLast, false /* delete */);
+
+ assert(c._bucketList == c._bucketFirst, "check");
+ assert(c._bucketList->next() == c._bucketMiddle, "check");
+ assert(c._bucketList->next()->next() == c._bucketLast, "check");
+ assert(c._bucketList->next()->next()->next() == NULL, "check");
+
+ assert(c._bucketFirst->count() == 1, "check");
+ assert(c._bucketMiddle->count() == 1, "check");
+ assert(c._bucketLast->count() == 0, "check");
+ }
+
+ static void testRemoveDependentNmethodConvenienceFirst() {
+ TestNmethodBucketContext c;
+
+ nmethodBucket::remove_dependent_nmethod(c._bucketList, c._nmethodFirst);
+
+ assert(c._bucketList == c._bucketFirst, "check");
+ assert(c._bucketList->next() == c._bucketMiddle, "check");
+ assert(c._bucketList->next()->next() == c._bucketLast, "check");
+ assert(c._bucketList->next()->next()->next() == NULL, "check");
+
+ assert(c._bucketFirst->count() == 0, "check");
+ assert(c._bucketMiddle->count() == 1, "check");
+ assert(c._bucketLast->count() == 1, "check");
+ }
+
+ static void testRemoveDependentNmethodConvenienceMiddle() {
+ TestNmethodBucketContext c;
+
+ nmethodBucket::remove_dependent_nmethod(c._bucketList, c._nmethodMiddle);
+
+ assert(c._bucketList == c._bucketFirst, "check");
+ assert(c._bucketList->next() == c._bucketMiddle, "check");
+ assert(c._bucketList->next()->next() == c._bucketLast, "check");
+ assert(c._bucketList->next()->next()->next() == NULL, "check");
+
+ assert(c._bucketFirst->count() == 1, "check");
+ assert(c._bucketMiddle->count() == 0, "check");
+ assert(c._bucketLast->count() == 1, "check");
+ }
+
+ static void testRemoveDependentNmethodConvenienceLast() {
+ TestNmethodBucketContext c;
+
+ nmethodBucket::remove_dependent_nmethod(c._bucketList, c._nmethodLast);
+
+ assert(c._bucketList == c._bucketFirst, "check");
+ assert(c._bucketList->next() == c._bucketMiddle, "check");
+ assert(c._bucketList->next()->next() == c._bucketLast, "check");
+ assert(c._bucketList->next()->next()->next() == NULL, "check");
+
+ assert(c._bucketFirst->count() == 1, "check");
+ assert(c._bucketMiddle->count() == 1, "check");
+ assert(c._bucketLast->count() == 0, "check");
+ }
+
+ static void testRemoveDependentNmethod() {
+ testRemoveDependentNmethodFirstDeleteImmediately();
+ testRemoveDependentNmethodMiddleDeleteImmediately();
+ testRemoveDependentNmethodLastDeleteImmediately();
+
+ testRemoveDependentNmethodFirstDeleteDeferred();
+ testRemoveDependentNmethodMiddleDeleteDeferred();
+ testRemoveDependentNmethodLastDeleteDeferred();
+
+ testRemoveDependentNmethodConvenienceFirst();
+ testRemoveDependentNmethodConvenienceMiddle();
+ testRemoveDependentNmethodConvenienceLast();
+ }
+
+ static void test() {
+ testRemoveDependentNmethod();
+ }
+};
+
+void TestNmethodBucket_test() {
+ TestNmethodBucket::test();
+}
+
+#endif