On 12/17/19 4:21 AM, Robbin Ehn wrote:
Hi Coleen,
On 12/16/19 9:21 PM, [email protected] wrote:
http://cr.openjdk.java.net/~rehn/8235912/v1/webrev/src/hotspot/share/prims/jvmtiImpl.cpp.udiff.html
+ NativeAccess<>::oop_store(_class_holder, class_holder_oop);
This should probably be:
41 NativeAccess<IS_DEST_UNINITIALIZED>::oop_store(handle, obj);
I have not seen any stores to oopStorage that use that?
oopStorage should be 'initialized'.
So I prefer not adding another decorator if it's not needed.
That would just be confusing.
It's in the ClassLoaderData initialization. I don't know what it means,
you'd have to ask someone who knows. I don't think it matters though.
Coleen
You can leave out using OopHandle. I have a patch to add the missing
functionality and add it to your code. Actually, I was looking to
see how much OopHandle is used to see if it's helping anything and
there is a lot of code using it. Most of it is to hide oop* in
ClassLoaderData.
This change otherwise looks great.
Thanks, Robbin
Thanks,
Coleen
Thanks for having a look, Robbin
On 12/16/19 1:32 PM, [email protected] wrote:
I have to think about this. Could there be breakpoints in old
emcp methods that we do not remove? The metadata_do function is
trying to keep old Methods from being deleted while there are still
references to them.
http://cr.openjdk.java.net/~rehn/8235912/v1/webrev/src/hotspot/share/prims/jvmtiImpl.hpp.udiff.html
+ oop* _class_holder; // keeps _method memory from being deallocated
We created the class OopHandle to encapsulate strong oopStorage
references, although it's missing oop_store. Can you use that?
Coleen
On 12/16/19 4:47 AM, Robbin Ehn wrote:
Hi all, please review.
From issue, https://bugs.openjdk.java.net/browse/JDK-8235912:
JvmtiBreakpoints are walked via VMThread oops_do (the breakpoint
is in a vm operation) before they are installed in the safeopint
and after they have been installed, walked with
JvmtiCurrentBreakpoints::oops_do().
By putting the class holder inside oopStorage there is no need for
this.
JvmtiCurrentBreakpoints::metadata_do is not needed because
redefine classes actually removes the breakpoints before updating
them (so there is no breakpoints to update).
We can just remove metadata_do.
I also removed some unused code.
Changeset:
http://cr.openjdk.java.net/~rehn/8235912/v1/webrev/
Passes several runs of nsk jvmti/jdi and t1-7.
Thanks, Robbin
