RFR (10) (S) 8175817: Clean up Solaris signal code: SIGUSR2, SIGasync, SIGJVM1/2

[Robbin Ehn]

Hi David,

os_solaris.cpp:
3948   DO_SIGNAL_CHECK(ASYNC_SIGNAL);
Maybe move this to line 3938 with the other checks.

Looks good, thanks for fixing.

/Robbin

On 03/16/2017 02:00 PM, David Holmes wrote:
> Bug: https://bugs.openjdk.java.net/browse/JDK-8175817
>
> webrev: http://cr.openjdk.java.net/~dholmes/8175817/webrev/
>
> On Solaris SIGasync represents what we call the "SR signal" on other platforms (the event-based suspend/resume signal), and it is hardwired to SIGJVM2 (a dedicated JVM
> signal on Solaris 10+).
>
> As this signal is hard-wired and has not been user-definable at runtime for a very long time, we can do away with the SIGasync field and its setter and getter, and simply
> define ASYNC_SIGNAL as SIGJVM2 (not SIGUSR2 as the code currently suggests!). Once this is a build time constant it simplifies some other code.
>
> We can also stop trying to account for SIGJVM1/2 not existing as they must exist on the supported Solaris platforms.
>
> We can also stop trying to deal with an older libjsig (the logic for which has a bug anyway: used <= instead of < in the version check).
>
> Overall just a bit of simplification and cleanup. No functional changes.
>
> Testing: JPRT
>
> Thanks,
> David
>