RFR (S) 8181170: resolved_references array leaks for RedefineClasses

[Jiangli Zhou]

Hi Coleen,

This looks good to me. The InstanceKlass::deallocate_contents() takes care of the shared case and only calls MetadataFactory::free_metadata(loader_data, constants()) if the constants !is_shared(). So, we don’t need to worry about any possible side effect of calling G1SATBCardTableModRefBS::enqueue() on archived resolved_references object. Just to be safe, how about adding an assert in ConstantPoolCache::deallocate_contents() to make sure the current cache is !is_shared()? No need for a new webrev if you decide to add the assert.

void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
...
  if (constants() != NULL) {
    assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
    if (!constants()->is_shared()) {
      MetadataFactory::free_metadata(loader_data, constants());
    }


Thanks,
Jiangli

> On Aug 29, 2017, at 7:01 AM, coleen.phillimore at oracle.com wrote:
> 
> Summary: clear out resolved_reference from ClassLoaderData::_handles
> 
> See the bug for details.
> 
> open webrev at http://cr.openjdk.java.net/~coleenp/8181170.01/webrev
> bug link https://bugs.openjdk.java.net/browse/JDK-8181170
> 
> Tested with:
> tier1 hotspot (includes most hotspot jtreg tests)
> tonga nsk.jvmti, nsk.jdi (internal tests)
> jdk/test/java/lang/instrument
> jdk/test/com/sun/jdi
> 
> Thanks,
> Coleen
> 
>