RFR: 8219241: Provide basic virtualization related info in the hs_error file on linux/windows x86_64

[Baesken, Matthias]

> 
> My remaining query is why we need the OS specific checks and code in
> os-cpu files? Isn't this just cpu specific? Even if a particular OS
> doesn't support virtualization, won't the cpuid query simply report "no
> virtualization"?
>

Hi David,  if you are referring to  these  os-cpu files  :

src/hotspot/os_cpu/linux_x86/vm_version_linux_x86.cpp
src/hotspot/os_cpu/windows_x86/vm_version_windows_x86.cpp

we have different coding available  because  I am not aware  of a cross OS  API/coding to get   the cpu id info.
That’s why different coding for LINUX/Windows.


Best regards, Matthias


> -----Original Message-----
> From: David Holmes <david.holmes at oracle.com>
> Sent: Donnerstag, 4. April 2019 03:16
> To: Baesken, Matthias <matthias.baesken at sap.com>; 'hotspot-
> dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>
> Cc: Doerr, Martin <martin.doerr at sap.com>
> Subject: Re: RFR: 8219241: Provide basic virtualization related info in the
> hs_error file on linux/windows x86_64
> 
> Hi Matthias,
> 
> This is looking much better/simpler - thanks!
> 
> My remaining query is why we need the OS specific checks and code in
> os-cpu files? Isn't this just cpu specific? Even if a particular OS
> doesn't support virtualization, won't the cpuid query simply report "no
> virtualization"?
> 
> Thanks,
> David
> 
> On 4/04/2019 12:43 am, Baesken, Matthias wrote:
> >> 1. Why do we have/need os::<os>::print_virtualization_info when we also
> >> have VM_Version::print_platform_virtualization_info?
> >>
> >
> > Hi David,  I have to agree  -  we do not really need both .
> > So I removed   os::<os>::print_virtualization_info    and   call
> VM_Version::print_platform_virtualization_info(st);     at  the places where
> the output is done.
> >
> > Regarding point  2. :
> >
> > I now  just use   print_platform_virtualization_info,
> print_detected_virtualization  has been removed .
> > print_platform_virtualization_info   is doing  the output   (differs  for
> vm_version_  s390 /  ppc / x86_64 ) .
> >
> > The  new webrev   is simpler, with less methods  :
> >
> >
> > http://cr.openjdk.java.net/~mbaesken/webrevs/8219241.4/
> >
> > Best regards, Matthias
> >
> >
> >> -----Original Message-----
> >> From: David Holmes <david.holmes at oracle.com>
> >> Sent: Freitag, 29. März 2019 01:16
> >> To: Baesken, Matthias <matthias.baesken at sap.com>; 'hotspot-
> >> dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>
> >> Cc: Doerr, Martin <martin.doerr at sap.com>
> >> Subject: Re: RFR: 8219241: Provide basic virtualization related info in the
> >> hs_error file on linux/windows x86_64
> >>
> >> Hi Matthias,
> >>
> >> I have two issues with this API:
> >>
> >> 1. Why do we have/need os::<os>::print_virtualization_info when we also
> >> have VM_Version::print_platform_virtualization_info?
> >>
> >> 2. I don't like the fact that the there are two ways to define the
> >> platform specific information:
> >>     a) override VM_Version::print_platform_virtualization_info; or
> >>     b) hook into the get_detected_virtualization switch
> >>
> >> And IIUC code that uses (a) relies on the switch doing nothing
> >> (NoVirtualization) and code that uses (b) relies on
> >> print_platform_virtualization_info doing nothing!
> >>
> >> Why doesn't the default implementation of
> >> VM_Version::print_platform_virtualization_info define the
> >> get_detected_virtualization() switch logic, and do away with
> >> Abstract_VM_Version::print_detected_virtualization? Code that wants to
> >> print this info can just call
> >> VM_Version::print_platform_virtualization_info().
> >>
> >> Sorry but I just find the current proposal has too many methods and an
> >> unclear structure.
> >>
> >> David
> >