Re: [Qemu-devel] [PATCH 3/5] tests/vm: Do not abuse parallelism when KVM is not available

[Fam Zheng <famz@redhat.com>]

On Mon, 07/16 23:48, Philippe Mathieu-Daudé wrote:
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  tests/vm/basevm.py | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/vm/basevm.py b/tests/vm/basevm.py
> index 1f4ad04c32..715e433142 100755
> --- a/tests/vm/basevm.py
> +++ b/tests/vm/basevm.py
> @@ -233,7 +233,7 @@ def main(vmcls):
>              return 1
>          logging.basicConfig(level=(logging.DEBUG if args.debug
>                                     else logging.WARN))
> -        vm = vmcls(debug=args.debug, vcpus=args.jobs)
> +        vm = vmcls(debug=args.debug, vcpus=args.jobs if kvm_available() else 0)
>          if args.build_image:
>              if os.path.exists(args.image) and not args.force:
>                  sys.stderr.writelines(["Image file exists: %s\n" % args.image,
> @@ -244,7 +244,7 @@ def main(vmcls):
>              vm.add_source_dir(args.build_qemu)
>              cmd = [vm.BUILD_SCRIPT.format(
>                     configure_opts = " ".join(argv),
> -                   jobs=args.jobs)]
> +                   jobs=args.jobs if kvm_available() else 1)]
>          else:
>              cmd = argv
>          vm.boot(args.image + ",snapshot=on")
> -- 
> 2.18.0
> 

Could you instead change this line

    parser.add_option("--jobs", type=int, default=multiprocessing.cpu_count() / 2,
                      help="number of virtual CPUs")

to use kvm_available()? With another helper function to contain the line width,
probably:

    ..., default=get_default_jobs(), help=...

and

    def get_default_jobs():
        if kvm_available():
            return ...
        else:
            return ...

Fam