RFR : 8222280 : Provide virtualization related info in the hs_error file on AIX

[Langer, Christoph]

Hi Matthias,

I think the change is good.

As regards to libperfstat usage: I think we should clean this up and try to link during the build/use the system headers. We don't need to support AIX V5.3 as build release any longer and probably all required functionality is contained in the headers of the required minimum AIX build release. This needs to be doublechecked when attempting the cleanup, though.

Best regards
Christoph

> -----Original Message-----
> From: hotspot-dev <hotspot-dev-bounces at openjdk.java.net> On Behalf Of
> Baesken, Matthias
> Sent: Freitag, 12. April 2019 14:52
> To: ppc-aix-port-dev at openjdk.java.net; 'hotspot-dev at openjdk.java.net'
> <hotspot-dev at openjdk.java.net>
> Subject: RFR : 8222280 : Provide virtualization related info in the hs_error file
> on AIX
> 
> Hello, please review the following  change . It brings  AIX related
> virtualization information into the hs_err file .
> 
> While preparing the patch  I wondered a bit  about the   libperfstat   usage  in
> OpenJDK  (Hotspot  compared to JDK ).
> In JDK  we link already to  libperfstat at build time , see  :
> 
> jdk/make/lib/Lib-java.management.gmk
> BUILD_LIBMANAGEMENT
> 
> jdk/make/lib/Lib-jdk.management.gmk
> BUILD_LIBMANAGEMENT_EXT
> 
> 
> While in hotspot dlopen/dladdr is used ,  see
> jdk/src/hotspot/os/aix/libperfstat_aix.cpp
> 
> 58 bool libperfstat::init() {
> 59
> 60  // Dynamically load the libperfstat porting library.
> 61  g_libhandle = dlopen("/usr/lib/libperfstat.a(shr_64.o)", RTLD_MEMBER |
> RTLD_NOW);
> 62  if (!g_libhandle) {
> 63    trcVerbose("Cannot load libperfstat.a (dlerror: %s)", dlerror());
> 64    return false;
> 65  }
> 
> we  dlopen  and then resolve symbols at runtime.
> This was probably a good thing back then when AIX 5.3 was still supported as
> build platform  ,  but I am not sure if it is still needed these days  on AIX
> 7.1/7.2  .
> 
> But  in case  the  dlopen/dladdr approach  in HS  is still needed/wanted , I
> would  switch  to  the   libperfstat::   functions .
> 
> Bug/webrev  :
> 
> https://bugs.openjdk.java.net/browse/JDK-8222280
> 
> http://cr.openjdk.java.net/~mbaesken/webrevs/8222280_aix_virt.0/
> 
> 
> Thanks , Matthias