RFR: 8253742: POSIX signal code cleanup [v5]

[David Holmes]

On Fri, 6 Nov 2020 20:13:10 GMT, Gerard Ziemski <gziemski at openjdk.org> wrote:

>> hi all,
>> 
>> Please review this followup to [JDK-8252324 Signal related code should be shared among POSIX platforms](https://bugs.openjdk.java.net/browse/JDK-8252324), where several issues were identified for a cleanup. This change addresses them all:
>> 
>> #1 David's feedback - removed non POSIX SIGNIFICANT_SIGNAL_MASK code
>> 
>> #2 David's feedback - used unblock_program_error_signals() on all platforms (reverted for JDK-8252533)
>> 
>> #3 David's feedback - used single JVM_handle_posix_signal API for all POSIX platforms (reverted for JDK-8255711)
>> 
>> #4 Coleen's feedback - cleanup header files in src/hotspot/os/posix/signals_posix.hpp
>> 
>> #5 Coleen's feedback - hid SR_signum assignment in src/hotspot/os/posix/signals_posix.hpp to avoid having to include <signal.h>
>> 
>> #6 Coleen's feedback - factored out print_signal_handlers()
>> 
>> #7 Thomas' feedback - factored out common POSIX os::SuspendedThreadTask::internal_do_task()
>> 
>> #8 Thomas's feedback - factored out common POSIX signal initialization code
>> 
>> #9 YaSuenag's feedback - used JVM_handle_posix_signal for the common API
>> 
>> #10 YaSuenag's feedback - unified logging out of the scope for this fix
>> 
>> #11 YaSuenag's feedback - memset usage in PosixSignals::jdk_misc_signal_init() correct?
>
> Gerard Ziemski has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Thomas' feedback - cleanup ucontext_get_pc/ucontext_set_pc

Latest changes all look good.

Only open issue is the include, or not, of signal.h.

Thanks,
David

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Marked as reviewed by dholmes (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/636