RFR (S): 8239070: Memory leak when unsuccessfully mapping in archive regions

[Thomas Schatzl]

Hi,

On 15.02.20 09:20, Kim Barrett wrote:
>> On Feb 14, 2020, at 11:08 AM, Ioi Lam <ioi.lam at oracle.com> wrote:
>>
>> Hi Thomas,
>>
>> Thanks for fixing this issue. Freeing the array at each exit point seems error prone. How about: refactoring the function to a FileMapInfo::map_heap_data_impl function, allocate inside FileMapInfo::map_heap_data(), call map_heap_data() and if it returns false, free the array in a single place.
> 
> Rather than splitting up the function, one could add a local cleanup handler:
> 
>    ... create and initialize regions object ...
>    struct Cleanup {
>      MemRegion* _regions;
>      bool _aborted;
>      Cleanup(MemRegion* regions) : _regions(regions), _aborted(true) {}
>      ~Cleanup() { if (_aborted) FREE_C_HEAP_ARRAY(MemRegion, _regions); }
>    } cleanup(regions);
>    ...
>    cleanup._aborted = false;
>    return true;
> }
> 

   I implemented that as it is least intrusive in the end.

http://cr.openjdk.java.net/~tschatzl/8239070/webrev.1/ (full, no point 
in providing diff)

Thanks,
   Thomas