RFR: ZGC: Simplify the ZPage life cycle

[Per Liden]

Thanks Erik!

/Per

On 3/18/19 12:12 PM, Erik Österlund wrote:
> Hi Per,
> 
> Seems like this safe delete business should have a scoped object for 
> enabling/disabling the deferred deletes. But let's leave it for now and 
> think about that for another day. Looks good!
> 
> /Erik
> 
> On 2019-03-15 21:28, Per Liden wrote:
>> On 03/15/2019 03:08 PM, Per Liden wrote:
>>> On 03/14/2019 03:20 PM, Stefan Karlsson wrote:
>>>> Hi Per,
>>>>
>>>> Most of this look good.
>>>
>>> Thanks for reviewing, Stefan!
>>>
>>> [...]
>>>>> 8220600: ZGC: Delete ZPages using ZSafeDelete
>>>>> ---------------------------------------------
>>>>> Remove the concept of deferred destruction of detached ZPages, and 
>>>>> instead delete ZPages using ZSafeDelete.
>>>>>
>>>>> https://bugs.openjdk.java.net/browse/JDK-8220600
>>>>> http://cr.openjdk.java.net/~pliden/8220600/webrev.0
>>>>>
>>>>
>>>> +  // Do not allow pages to be destroyed
>>>> +  _page_allocator.enable_safe_delete();
>>>>
>>>> +  // Allow pages to be destroyed
>>>> +  _page_allocator.disable_safe_delete();
>>>>
>>>> It sounds weird to disable safe deletes. Maybe rename these 
>>>> functions to enable_deferred_deletes/disable_deferred_deletes?
>>>
>>> I agree, renamed.
>>>
>>>>
>>>> ------
>>>>
>>>> We also need to use the safe delete mechanism when printing the page 
>>>> table. That code gets exercised when run jcmd VM.info.
>>>
>>> Good point, fixed.
>>>
>>> Updated affected webrev:
>>
>> Err, those URLs should be s/dff/diff/ ...
>>
>>>
>>> 8220599: ZGC: Introduce ZSafeDelete
>>> -----------------------------------
>>> http://cr.openjdk.java.net/~pliden/8220599/webrev.1-dff
>>
>> http://cr.openjdk.java.net/~pliden/8220599/webrev.1-diff
>>
>>> http://cr.openjdk.java.net/~pliden/8220599/webrev.1
>>>
>>>
>>> 8220600: ZGC: Delete ZPages using ZSafeDelete
>>> ---------------------------------------------
>>> http://cr.openjdk.java.net/~pliden/8220600/webrev.1-dff
>>
>> http://cr.openjdk.java.net/~pliden/8220600/webrev.1-diff
>>
>>> http://cr.openjdk.java.net/~pliden/8220600/webrev.1
>>>
>>>
>>> 8220601: ZGC: Delete ZNMethodTableEntry arrays using ZSafeDelete
>>> ----------------------------------------------------------------
>>> http://cr.openjdk.java.net/~pliden/8220601/webrev.1-dff
>>
>> http://cr.openjdk.java.net/~pliden/8220601/webrev.1-diff
>>
>>> http://cr.openjdk.java.net/~pliden/8220601/webrev.1
>>>
>>>
>>> /Per
>