--- a/hotspot/src/share/vm/oops/method.cpp Tue Jul 14 16:28:53 2015 +0200
+++ b/hotspot/src/share/vm/oops/method.cpp Wed Jul 15 12:24:41 2015 -0700
@@ -422,6 +422,11 @@
if (!mh->init_method_counters(counters)) {
MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
}
+
+ if (LogTouchedMethods) {
+ mh->log_touched(CHECK_NULL);
+ }
+
return mh->method_counters();
}
@@ -2130,6 +2135,85 @@
}
#endif // INCLUDE_SERVICES
+// LogTouchedMethods and PrintTouchedMethods
+
+// TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
+// the Method may be garbage collected. Let's roll our own hash table.
+class TouchedMethodRecord : CHeapObj<mtTracing> {
+public:
+ // It's OK to store Symbols here because they will NOT be GC'ed if
+ // LogTouchedMethods is enabled.
+ TouchedMethodRecord* _next;
+ Symbol* _class_name;
+ Symbol* _method_name;
+ Symbol* _method_signature;
+};
+
+static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
+static TouchedMethodRecord** _touched_method_table = NULL;
+
+void Method::log_touched(TRAPS) {
+
+ const int table_size = TOUCHED_METHOD_TABLE_SIZE;
+ Symbol* my_class = klass_name();
+ Symbol* my_name = name();
+ Symbol* my_sig = signature();
+
+ unsigned int hash = my_class->identity_hash() +
+ my_name->identity_hash() +
+ my_sig->identity_hash();
+ juint index = juint(hash) % table_size;
+
+ MutexLocker ml(TouchedMethodLog_lock, THREAD);
+ if (_touched_method_table == NULL) {
+ _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
+ mtTracing, CURRENT_PC);
+ memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
+ }
+
+ TouchedMethodRecord* ptr = _touched_method_table[index];
+ while (ptr) {
+ if (ptr->_class_name == my_class &&
+ ptr->_method_name == my_name &&
+ ptr->_method_signature == my_sig) {
+ return;
+ }
+ if (ptr->_next == NULL) break;
+ ptr = ptr->_next;
+ }
+ TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
+ my_class->set_permanent(); // prevent reclaimed by GC
+ my_name->set_permanent();
+ my_sig->set_permanent();
+ nptr->_class_name = my_class;
+ nptr->_method_name = my_name;
+ nptr->_method_signature = my_sig;
+ nptr->_next = NULL;
+
+ if (ptr == NULL) {
+ // first
+ _touched_method_table[index] = nptr;
+ } else {
+ ptr->_next = nptr;
+ }
+}
+
+void Method::print_touched_methods(outputStream* out) {
+ MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
+ out->print_cr("# Method::print_touched_methods version 1");
+ if (_touched_method_table) {
+ for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
+ TouchedMethodRecord* ptr = _touched_method_table[i];
+ while(ptr) {
+ ptr->_class_name->print_symbol_on(out); out->print(".");
+ ptr->_method_name->print_symbol_on(out); out->print(":");
+ ptr->_method_signature->print_symbol_on(out); out->cr();
+ ptr = ptr->_next;
+ }
+ }
+ }
+}
+
// Verification
void Method::verify_on(outputStream* st) {