RFR(XXS): 8007147: Trace event ExecuteVMOperation may get dangling pointer
Dean Long
dean.long at oracle.com
Tue Feb 19 11:30:37 PST 2013
On 2/19/2013 11:00 AM, Staffan Larsen wrote:
>
> On 19 feb 2013, at 19:56, Dean Long <dean.long at oracle.com
> <mailto:dean.long at oracle.com>> wrote:
>
>> When the VM_Operation is created, we could take a snapshot of the
>> thread_id of the caller, then use that later.
>
> One problem with that is if the thread_id gets reused for a new thread
> quickly after the old thread terminates. This is perhps ulikely, but
> could happen.
>
>> Or we could block the creating thread from fully exiting until the VM
>> op executes.
>
> That would introduce a lot more synchronization and state to keep
> track of.
>
I think we could do it with a reference count on the thread, a wait in
thread exit, and a notify in the VM thread.
We have a similar dangling pointer problem with JVMTI (7154963), and a
reference count should solve that
problem as well.
dl
> /Staffan
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mail.openjdk.java.net/pipermail/hotspot-runtime-dev/attachments/20130219/b8dbc521/attachment.html
More information about the hotspot-runtime-dev
mailing list