RFR: 8224974: Implement JEP 352

[Dmitry Chuyko]

Hi Andrew,

Just a minor style thing in MapSyncFail test: can "true" and "false" 
(the mode) be "READ_WRITE_SYNC" and "READ_ONLY_SYNC" instead?

-Dmitry

On 8/19/19 2:29 PM, Andrew Dinn wrote:
> Hi Alan,
>
> ...................
> I renamed the test to MapSyncFail and modified it to run without
> restriction to a specific os or cpu.
>
> I also generalized it to run twice with a boolean arg which selects mode
> READ_ONLY_SYNC on the first run and READ_WRITE_SYNC on the second one.
>
> The logic of the test is now to expect
>
>   1) IOException if Unsafe.isWriteBackEnabled -> true
>   2) UnsupportedOperationException if Unsafe.isWriteBackEnabled -> false
>
> If the wrong exception or neither exception is thrown the test fails.
>
> Case 1 currently only applies for x86_64.
> Case 2 applies for all other architectures.
>
>> In passing, MappedByteBuffer load/isLoaded check the fd value before
>> isSync, can force() do the same? Also the @return on the private isSync
>> method is very wordy and I don't think needs to duplicate the method
>> description.
> Sure, I have modified force() to do that check first.
>
> Of course, that means that force(int, int) is going to repeat the same
> test -- it has to because it may be called direct without going via force().
>
> However, that's not really a problem since the compiler should elide the
> repeated check.
>
> I also shortened the text following the @return annotation as requested.
>
> Updated webrev:
>
>    http://cr.openjdk.java.net/~adinn/8224974/webrev.12
>
> Testing:
>
> Test PmemTest:
>    passes as expected on x86_64 (only arch for which DAX file system is
> available)
>    fails to pass as expected on aarch64 and x86_32 (however, this case is
> covered by the next test)
>
> Test MapSyncFail:
>    passes with expected exceptions on Linux for x86_64 (IOException),
> aarch64 and x86_32 (UnsupportedOperationException).
>    not tested on other arch/OS combinations (I have no access to the
> necessary kit).
>
> Red Hat MW tests:
>    All still passing successfully
>
> submit test:
>    still in progress
>
> Is it ok to push if the submit test comes back clean?
>
> regards,
>
>
> Andrew Dinn
> -----------
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