RFR(XXS) 8199741: NMT: Tag safepoint polling pages

[coleen.phillimore at oracle.com]

On 3/16/18 12:05 PM, Zhengyu Gu wrote:
>
>
> On 03/16/2018 11:50 AM, coleen.phillimore at oracle.com wrote:
>>
>> Yay, a quick code review.  Is there a better mt tag than mtInternal 
>
> Thanks, Coleen.
>
>
>> though?  There are too many mtInternal allocations.  Can you add 
>> mtSafepoint or mtSynchronize (or better name?) and we could have an 
>> RFE to make some of these into the same:
>>
>> share/runtime/semaphore.hpp:class Semaphore : public 
>> CHeapObj<mtInternal> {
>> share/runtime/mutex.hpp:class Monitor : public CHeapObj<mtInternal> {
>> share/runtime/objectMonitor.cpp:  return AllocateHeap(size, mtInternal);
>> share/runtime/objectMonitor.cpp:  char * knobs = (char *) 
>> os::malloc(sz + 2, mtInternal);
>> share/runtime/monitorChunk.cpp:  _monitors           = 
>> NEW_C_HEAP_ARRAY(BasicObjectLock, number_on_monitors, mtInternal);
>>
>> Or even mtOS so we can move some of the os allocations to this category?
>
> Of course, we can have as many as 255 categories, another RFE?

Yes.
thanks!
Coleen
>
>
> -Zhengyu
>
>>
>> Why is nothing simple?! :)
>>
>> Coleen
>>
>> On 3/16/18 11:34 AM, Zhengyu Gu wrote:
>>> A trivial fix to add NMT tag to Safepoint poll pages.
>>>
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8199741
>>> Webrev: http://cr.openjdk.java.net/~zgu/8199741/webrev.00/
>>>
>>> Test:
>>>   Eyeball NMT output on Linux x64.
>>>
>>> Thanks,
>>>
>>> -Zhengyu
>>