[11u] RFR: 8244241: Add paddings for TaskQueueSuper to reduce false-sharing cache contention

[Lindenmaier, Goetz]

Hi,

Christoph and I sent several replies to this mail.
For some reason they are not delivered to the archives.
I get them back with security scan issues ...
So I write a clean answer here, maybe this works:

We saw build problems on mac. It does not like sizeof(_bottom).

If I use sizeof(uint) it works on mac. Uint is also the
term jdk/jdk uses here.
I put it into our CI again to make sure all platforms build.
I'll  update you tomorrow if it worked.

Also I think we should move the line up, just below the
declaration of _bottom, as it now depends on the
type used there.

Patrick, the bug id in the subject of this mail is wrong. I kept the 
wrong one in this answer so the mail thread does not break.

Also, please remove the "Summary:" line in webrev.02. It only 
repeats the bug title, and thus is redundant. 
You can use the Summary line if you want to add more than the bug title.
You might add Summary: This is a downport of a part of JDK-8243326

Best regards,
  Goetz.