--- a/hotspot/src/share/vm/classfile/symbolTable.cpp Fri Jun 14 08:02:32 2013 +0200
+++ b/hotspot/src/share/vm/classfile/symbolTable.cpp Tue Jun 18 12:31:07 2013 -0700
@@ -598,6 +598,8 @@
bool StringTable::_needs_rehashing = false;
+volatile int StringTable::_parallel_claimed_idx = 0;
+
// Pick hashing algorithm
unsigned int StringTable::hash_string(const jchar* s, int len) {
return use_alternate_hashcode() ? AltHashing::murmur3_32(seed(), s, len) :
@@ -761,8 +763,18 @@
}
}
-void StringTable::oops_do(OopClosure* f) {
- for (int i = 0; i < the_table()->table_size(); ++i) {
+void StringTable::buckets_do(OopClosure* f, int start_idx, int end_idx) {
+ const int limit = the_table()->table_size();
+
+ assert(0 <= start_idx && start_idx <= limit,
+ err_msg("start_idx (" INT32_FORMAT ") oob?", start_idx));
+ assert(0 <= end_idx && end_idx <= limit,
+ err_msg("end_idx (" INT32_FORMAT ") oob?", end_idx));
+ assert(start_idx <= end_idx,
+ err_msg("Ordering: start_idx=" INT32_FORMAT", end_idx=" INT32_FORMAT,
+ start_idx, end_idx));
+
+ for (int i = start_idx; i < end_idx; i += 1) {
HashtableEntry<oop, mtSymbol>* entry = the_table()->bucket(i);
while (entry != NULL) {
assert(!entry->is_shared(), "CDS not used for the StringTable");
@@ -774,6 +786,27 @@
}
}
+void StringTable::oops_do(OopClosure* f) {
+ buckets_do(f, 0, the_table()->table_size());
+}
+
+void StringTable::possibly_parallel_oops_do(OopClosure* f) {
+ const int ClaimChunkSize = 32;
+ const int limit = the_table()->table_size();
+
+ for (;;) {
+ // Grab next set of buckets to scan
+ int start_idx = Atomic::add(ClaimChunkSize, &_parallel_claimed_idx) - ClaimChunkSize;
+ if (start_idx >= limit) {
+ // End of table
+ break;
+ }
+
+ int end_idx = MIN2(limit, start_idx + ClaimChunkSize);
+ buckets_do(f, start_idx, end_idx);
+ }
+}
+
void StringTable::verify() {
for (int i = 0; i < the_table()->table_size(); ++i) {
HashtableEntry<oop, mtSymbol>* p = the_table()->bucket(i);