On Mon, 7 Dec 2020 06:27:20 GMT, Chris Plummer <cjplum...@openjdk.org> wrote:
>> src/jdk.jdwp.agent/share/native/libjdwp/threadControl.c line 1560:
>>
>>> 1558: * garbage collected while the VM is suspended.
>>> 1559: */
>>> 1560: commonRef_pinAll();
>>
>> Can we have multiple VM.suspend calls? The suspendAllCount seems to suggest
>> that. In which case shouldn't we only pin on the 0->1 transition, and only
>> unpin on the 1->0 transition?
>
> That was something I pointed out in the pre-review, and it has been addressed
> in `commonRef_pinAll/unpinAll`:
>
> `568 if (gdata->pinAllCount == 1) {`
> `618 if (gdata->pinAllCount == 0) {`
> Okay. I would not have handled it at that level, but would have had
pinAll/unpinAll operate unconditionally, but the calls to those methods
being conditional based on the suspendAllCount.
>
>David
Well, that's assuming `pinAll()` will only ever be used by by `suspendAll()`.
One could imaging a future use, such as if `VirtualMachine.disableCollection()`
were ever to be added.
-------------
PR: https://git.openjdk.java.net/jdk/pull/1595
