On Mon, Jun 26, 2017 at 2:18 PM, Langer, Christoph <christoph.langer@sap.com> wrote:

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@openjdk.java.net] On Behalf Of Thomas Stüfe
Sent: Montag, 26. Juni 2017 12:57
To: ppc-aix-port-dev@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