RFR: JDK-8043630 Method os::yield_all() should be removed

[Zhengyu Gu]

On 5/22/2014 8:07 AM, David Holmes wrote:
> Hi Fred,
>
> Generally good to see this go but a couple of queries.
>
> src/share/vm/prims/jni.cpp
>
> You changed yield_all to yield but on Solaris (actually posix) that 
> still introduces the thread-state-transition so the 
> ThreadInVMfromNative would still seem to be needed.
>
> My memory is failing me here as I don't recall the details of the 
> switch to using os::posix::sleep on Solaris. But I note that in doing 
> so we have lost the semantics of sleep(0) that os::yield was relying 
> on - we lost the thr_yield call!
>
> src/share/vm/services/memTracker.hpp
>
> Aside: I'm curious to know why NakedYield does not work as well on 
> Windows - does it yield to the "wrong" thread?
My memory is that, the implementation of NakedYield on Windows is to 
call SwitchThread(), which only yields threads on the same processor.

Thanks,

-Zhengyu

>
> Cheers,
> David
>
> On 22/05/2014 9:22 PM, frederic parain wrote:
>> Please review the following change to remove
>> the os::yield_all() method. This method has
>> been source of issues for a long time and it's
>> time to get rid of it.
>>
>> CR:
>> https://bugs.openjdk.java.net/browse/JDK-8043630
>>
>> Webrev:
>> http://cr.openjdk.java.net/~fparain/8043630/webrev.00/
>>
>> This changeset has been tested with JPRT (builds and
>> tests), vm.quick.testlist, JDK jdk_core.
>> I also ran refworkload benchmarks suite which didn't
>> show any significant regression.
>>
>> Thanks,
>>
>> Fred
>>