RFR (XS): 8236177: assert(status == 0) failed: error ETIMEDOUT(60), cond_wait

[David Holmes]

Hi Gerard,

On 26/03/2020 4:03 am, gerard ziemski wrote:
> hi all,
> 
> Please review this "workaround" for now, which can not be called an 
> actual fix just yet, designed to figure out why on Mac OS X, we get 
> (very rarely) ETIMEDOUT when calling pthread_cond_wait() API. On other 
> hand, it might actually fix it.

The ETIMEDOUT should be treated as a "spurious wakeup" and we will 
naturally retry the wait if the condition is not yet met. All we have to 
do to our code is adjust the assert so that ETIMEDOUT doesn't cause it 
to fail.

Thanks,
David

> According to man pages, only EINVAL is allowed as an error code here, 
> but an inspection of the Darwin source code 
> https://opensource.apple.com/source/libpthread/libpthread-301.1.6/src/pthread_cond.c.auto.html 
> reveals that under some circumstances ETIMEDOUT may be returned.
> 
> The workaround for now is to try the operation again, after a short 
> delay (via yield() API). This will hopefully let us know whether that's 
> enough. If not, we may try to either keep trying the same operation 
> until it succeeds or return an error and let the code above handle it.
> 
> The workaround applies only to OS X.
> 
> bug link at https://bugs.openjdk.java.net/browse/JDK-8236177
> open webrev at http://cr.openjdk.java.net/~gziemski/8236177_rev1
> passes Mach hs-tier1,2,3,4,5
> 
> 
> cheers