RFR: 8181859: Monitor deflation is not checked in cleanup path

[Robbin Ehn]

Hi Aleksey,

On 06/14/2017 11:14 AM, Aleksey Shipilev wrote:
> On 06/14/2017 11:07 AM, Robbin Ehn wrote:
>> Full:
>> http://cr.openjdk.java.net/~rehn/8181859/2/webrev/
> 
> Looks good to me.

Thanks!

> 
> I would paranoidally add parentheses in this expression, but your choice.
> 
> return MonitorUsedDeflationThreshold > 0 && (monitors_used * 100LL) /
> gMonitorPopulation > MonitorUsedDeflationThreshold;

Discussed locally and this was suggested (looks good to me):

static bool monitors_used_above_threshold() {
   int monitors_used = gMonitorPopulation - gMonitorFreeCount;
   int monitor_useage = (monitors_used * 100LL) / gMonitorPopulation;
   return monitor_useage > MonitorUsedDeflationThreshold;
}

bool ObjectSynchronizer::is_cleanup_needed() {
   if (MonitorUsedDeflationThreshold > 0) {
     return monitors_used_above_threshold();
   }
   return false;
}

Carsten, Aleksey, are you good with this?

Full: http://cr.openjdk.java.net/~rehn/8181859/3/webrev/

Thanks, Robbin


> 
> Thanks,
> -Aleksey
> 
>