RFR(S): 8196565: AIX: Clean up os::javaTimeNanos according to AIX/PASE specification

[Langer, Christoph]

Hi David,

thanks for looking. I'll change my code to use that constant.

One question, as I'm currently looking at the os timing functions: Do you know why in os_solaris.cpp, in os::getTimesSecs(), the process_real_time value is not taken from the result of times() but from getTimeNanos()? Otherwise getTimeSecs would be a good candidate to move to os_posix.cpp ...

Best regards
Christoph

-----Original Message-----
From: David Holmes [mailto:david.holmes at oracle.com] 
Sent: Donnerstag, 1. Februar 2018 12:10
To: Langer, Christoph <christoph.langer at sap.com>; hotspot-runtime-dev at openjdk.java.net; ppc-aix-port-dev at openjdk.java.net
Subject: Re: RFR(S): 8196565: AIX: Clean up os::javaTimeNanos according to AIX/PASE specification

Hi Christoph,

On 1/02/2018 7:11 PM, Langer, Christoph wrote:
> Hi,
> 
> please review a fix for the os::javaTimeNanos method on AIX.
> 
> It implements the information we got from the AIX documentation and from the IBM folks regarding the behavior of mread_real_time on Pase.
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8196565
> Webrev: http://cr.openjdk.java.net/~clanger/webrevs/8196565.0/

I took a look as I was curious :) I recognized the Solaris code for 
ensuring monotonic time. :) It all seems to do as you describe.

One nit - instead of (1000 * 1000 * 1000) you can use:

const jlong NANOSECS_PER_SEC      = CONST64(1000000000);

from ./hotspot/share/utilities/globalDefinitions.hpp

Cheers,
David

> Thanks & Best regards
> Christoph
>