RFR: JDK-8155730: HeapInfoDCmd should get Heap_lock

[David Holmes]

On 9/05/2016 10:20 PM, Yasumasa Suenaga wrote:
> Hi all,
>
> I've sent review request for JDK-8155730.
> However, I found caller of Universe::heap()->print_*() in vmError.cpp .
> Thus I added MutexLocker(Ex) for Heap_lock to VMError::report() and
> VMError::print_vm_info().

Taking locks during VMError handling is problematic - we're executing  
from a signal handler and the VM is crashing. Much of what we do from  
VMError is "best effort".

David

> Could you review again?
>
>   http://cr.openjdk.java.net/~ysuenaga/JDK-8155730/webrev.01/
>
>
>> This needs to be reviewed by the GC folk not runtime. Please direct
>> followups to hotspot-gc-dev.
>
> Thanks, David!
>
>
> Yasumasa
>
>
> On 2016/05/06 13:11, David Holmes wrote:
>> Hi Yasumasa,
>>
>> This needs to be reviewed by the GC folk not runtime. Please direct
>> followups to hotspot-gc-dev.
>>
>> Thanks,
>> David
>>
>> On 30/04/2016 12:05 AM, Yasumasa Suenaga wrote:
>>> Hi all,
>>>
>>> This review request is related to [1].
>>>
>>> HeapInfoDCmd calls CollectedHeap::print_on().
>>> However, its call does not get Heap_lock.
>>>
>>> Heap_lock should be gotten from all heap operations.
>>>
>>> I uploaded webrev for this issue.
>>> Could you review it?
>>>
>>>   http://cr.openjdk.java.net/~ysuenaga/JDK-8155730/webrev.00/
>>>
>>> I cannot access JPRT.
>>> So I need a sponsor.
>>>
>>>
>>> Thanks,
>>>
>>> Yasumasa
>>>
>>>
>>> [1]
>>> http://mail.openjdk.java.net/pipermail/hotspot-runtime-dev/2016-April/019257.html
>>>
>>>
>>>