RFR(xxs): 8182864: [aix] os::print_native_callstack should not assert for primordial threadness

[Doerr, Martin]

Hi Thomas,

reviewed. I’m fine with it because the real issues wrt. primordial thread on AIX will be addressed in JDK-8171505.
Fixing native stack traces makes sense. Thanks for doing it.

Best regards,
Martin


From: ppc-aix-port-dev [mailto:ppc-aix-port-dev-bounces at openjdk.java.net] On Behalf Of Langer, Christoph
Sent: Montag, 26. Juni 2017 14:18
To: Thomas Stüfe <thomas.stuefe at gmail.com>
Cc: ppc-aix-port-dev at openjdk.java.net
Subject: RE: RFR(xxs): 8182864: [aix] os::print_native_callstack should not assert for primordial threadness

Hi Thomas,

the changes look good and from what I can read I also think this makes sense…

Best regards
Christoph

From: ppc-aix-port-dev [mailto:ppc-aix-port-dev-bounces at openjdk.java.net] On Behalf Of Thomas Stüfe
Sent: Montag, 26. Juni 2017 12:57
To: ppc-aix-port-dev at openjdk.java.net<mailto:ppc-aix-port-dev at openjdk.java.net>
Subject: RFR(xxs): 8182864: [aix] os::print_native_callstack should not assert for primordial threadness

Hi all,

may I please get reviews for this tiny change:

Webrev: http://cr.openjdk.java.net/~stuefe/webrevs/8182864-aix-do-not-assert-in-print-native-callstack/webrev.00/webrev/
Issue: https://bugs.openjdk.java.net/browse/JDK-8182864

In short, this fix removes some asserts from os::print_native_callstack() (via os::Aix::query_stack_dimensions()) which are not really useful. We assert that we do not run on the primordial thread, because otherwise the API used to retrieve the stack dimensions may fail.

This is wrong on two accounts:
1) the API now works for the primordial thread too, and does so since AIX 5.3 (?)  and
2) this is not the right place to assert for the primordial thread, because the stack trace shall always work.

The assert prevented us to get stack traces in some corner cases where we would have been perfectly able to get them.

For more background on the primordial thread issue on AIX, please see https://bugs.openjdk.java.net/browse/JDK-8171505

Thanks!

Thomas


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.openjdk.java.net/pipermail/ppc-aix-port-dev/attachments/20170626/476db61e/attachment.html>