8214271: Fast primitive to wake many threads

[Robbin Ehn]

Hi Andrew, thanks for having a look.

On 2018-11-24 12:12, Andrew Haley wrote:
> On 11/23/18 4:51 PM, Robbin Ehn wrote:
>> Webrev:
>> http://cr.openjdk.java.net/~rehn/8214271/webrev/
> 
> The code is rather lightly commented. In particular, it's not
> clear that a wait() might return spuriously from a futex and how
> you deal with that. Is it the case that users of this API are to be
> exposed to spurious wakeups? If so, you must say so in the comments.
> 

In my usage the futex is in the same memory location the entire processes
lifetime, therefore spurious wake ups with retval 0, AFAIK, do not happen?
But you are absolute right we should handle that. And EINTR totally slipped my
mind, so thanks!

Inc:
http://cr.openjdk.java.net/~rehn/8214271/2/inc/webrev/

Full:
http://cr.openjdk.java.net/~rehn/8214271/2/full/webrev/

/Robbin