8139247: Improper locking of MethodData::_extra_data_lock
Reviewed-by: dholmes, roland, dcubed
--- a/hotspot/src/share/vm/ci/ciMethodData.cpp Fri Mar 11 21:02:09 2016 +0100
+++ b/hotspot/src/share/vm/ci/ciMethodData.cpp Mon Mar 14 12:35:44 2016 +0300
@@ -81,7 +81,7 @@
void ciMethodData::load_extra_data() {
MethodData* mdo = get_MethodData();
- MutexLocker(mdo->extra_data_lock());
+ MutexLocker ml(mdo->extra_data_lock());
// speculative trap entries also hold a pointer to a Method so need to be translated
DataLayout* dp_src = mdo->extra_data_base();
@@ -103,16 +103,13 @@
switch(tag) {
case DataLayout::speculative_trap_data_tag: {
- ciSpeculativeTrapData* data_dst = new ciSpeculativeTrapData(dp_dst);
- SpeculativeTrapData* data_src = new SpeculativeTrapData(dp_src);
-
- data_dst->translate_from(data_src);
+ ciSpeculativeTrapData data_dst(dp_dst);
+ SpeculativeTrapData data_src(dp_src);
-#ifdef ASSERT
- SpeculativeTrapData* data_src2 = new SpeculativeTrapData(dp_src);
- assert(data_src2->method() == data_src->method() && data_src2->bci() == data_src->bci(), "entries changed while translating");
-#endif
-
+ { // During translation a safepoint can happen or VM lock can be taken (e.g., Compile_lock).
+ MutexUnlocker ml(mdo->extra_data_lock());
+ data_dst.translate_from(&data_src);
+ }
break;
}
case DataLayout::bit_data_tag:
@@ -120,9 +117,11 @@
case DataLayout::no_tag:
case DataLayout::arg_info_data_tag:
// An empty slot or ArgInfoData entry marks the end of the trap data
- return;
+ {
+ return; // Need a block to avoid SS compiler bug
+ }
default:
- fatal("bad tag = %d", dp_dst->tag());
+ fatal("bad tag = %d", tag);
}
}
}