[9] RFR(S): 8029343: CodeCache::allocate increments '_number_of_blobs' even if allocation fails.

[Tobias Hartmann]

Hi Vladimir,

On 06.05.2014 09:41, Vladimir Kozlov wrote:
> Parfait may complain about returning NULL and without guarantee.
> Please, test.

I tested the implementation with parfait and no new defects showed up.

Thanks,
Tobias

> Thanks,
> Vladimir
>
> On 5/6/14 12:27 AM, Tobias Hartmann wrote:
>> Hi,
>>
>> please review the following patch for bug 8029343.
>>
>> *Problem:*
>> (1) CodeCache::allocate(...) increments _number_of_blobs before the 
>> actual allocation is performed. In case the
>> allocation fails the counter is set to a wrong value.
>> (2) The guarantee(size >= 0, ...) is incorrect. Calling 
>> CodeCache::allocate(...) with size = 0 leads to a segmentation
>> fault. Further, a guarantee is too strong here. We can simply return 
>> NULL at runtime if the size is <= 0.
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8029343
>>
>> *Solution:*
>> (1) The increment is moved after the allocation.
>> (2) An assert is used instead of the guarantee and NULL is returned 
>> if size <= 0.
>> Webrev: http://cr.openjdk.java.net/~anoll/8029343/webrev.00/
>>
>> Thanks,
>> Tobias