David,
On Apr 11, 2013, at 2:15 PM, David Holmes wrote:
> Rickard,
> On 11/04/2013 9:51 PM, Rickard Bäckman wrote:
>> Hi all,
>>
>> can I please have reviews for this change.
>>
>> In the current implementation do_suspend uses spin loops to wait until a
>> thread has been suspended. I would like to change that to use semaphores to
>> reduce CPU usage and also make it easier to have a deterministic timeout.
>> Since we are posting to the semaphore in the signal handler we can't use
>> pthread_semaphore since it isn't async safe, which is why all
>> implementations uses low-level os-specific semaphore constructs.
>
> POSIX Semaphore sem_post() is async-signal safe:
Yes, and they are used in the implementation on Linux and BSD. Solaris uses the
sema_{post,wait,…} (since that was we were already using for other things) and
on Mac we use semaphore_{signal, wait, …}
/R
>
> http://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html#tag_15_04
>
> David
> -----
>
>> Bug: http://bugs.sun.com/view_bug.do?bug_id=8011882
>> Webrev: http://cr.openjdk.java.net/~rbackman/8011882/
>>
>> Thanks
>> /R
>>
