Code Review Request for 7107613, 7107616, 7185471

[Weijun Wang]

On 07/26/2012 08:21 AM, Valerie (Yu-Ching) Peng wrote:
> Hi, Max or Xuelei,
>
> Either of you have cycles to review the following 3 perf related fixes?
> 7107613: scalability bloker in javax.crypto.CryptoPermissions
> 7107616: scalability bloker in javax.crypto.JceSecurityManager
> 7185471: Avoid key expansion when AES cipher is re-init w/ the same key
>
> Webrevs are at:
> http://cr.openjdk.java.net/~valeriep/7107613

Looks fine.

> http://cr.openjdk.java.net/~valeriep/7107616

You have

  122         CryptoPermissions appPerms = exemptCache.get(callerCodeBase);
  123         // Found result in cache
  124         if (appPerms != null) {
  125             if (appPerms == CACHE_NULL_MARK) appPerms = null;
  126         } else {
  127             synchronized (this.getClass()) {
  128                 appPerms = getAppPermissions(callerCodeBase);
  129                 exemptCache.putIfAbsent(callerCodeBase,
  130                     (appPerms == null? CACHE_NULL_MARK:appPerms));
  131             }
  132         }

This is not as optimized as before, that there is a chance 
getAppPermissions could be called twice, and this seems to make the 
synchronized block not worth syncing.

> http://cr.openjdk.java.net/~valeriep/7185471

I haven't looked at this yet. Seems a lot of math there.

Thanks
Max

>
> The changes are for JDK 8. May be backported to 7u later if necessary,
> Thanks,
> Valerie