Re: [AUTOTEST PATCH 2/2] KVM-test: Move two 'remote_login' out of try block in kvm_vm.py

[Yolkfull Chow <yzhou@redhat.com>]

On Thu, Dec 31, 2009 at 05:03:21AM -0500, Michael Goldish wrote:
> 
> ----- "Yolkfull Chow" <yzhou@redhat.com> wrote:
> 
> > If vm.remote_login failed 'session.close()' can result in exception
> > in finally clause. This patch fix the problem.
> > 
> > Signed-off-by: Yolkfull Chow <yzhou@redhat.com>
> > ---
> >  client/tests/kvm/kvm_vm.py |   51
> > +++++++++++++++++++++----------------------
> >  1 files changed, 25 insertions(+), 26 deletions(-)
> > 
> > diff --git a/client/tests/kvm/kvm_vm.py b/client/tests/kvm/kvm_vm.py
> > index 7229b79..f746331 100755
> > --- a/client/tests/kvm/kvm_vm.py
> > +++ b/client/tests/kvm/kvm_vm.py
> > @@ -827,40 +827,39 @@ class VM:
> >          """
> >          Get the cpu count of the VM.
> >          """
> > +        session = self.remote_login()
> > +        cmd = self.params.get("cpu_chk_cmd")
> >          try:
> > -            session = self.remote_login()
> > -            if session:
> > -                cmd = self.params.get("cpu_chk_cmd")
> > -                s, count = session.get_command_status_output(cmd)
> > -                if s == 0:
> > -                    return int(count)
> > +            s, count = session.get_command_status_output(cmd)
> > +            if s == 0:
> > +                return int(count)
> >              return None
> >          finally:
> > -            session.close()
> > +            if session:
> > +                session.close()
> 
> If self.remote_login() fails, session will be None, and then the attempted
> call to session.get_command_status_output() will raise an exception which
> will fail the test with a rather ugly "reason" string.
> 
> I think this form is preferable:
> 
> session = self.remote_login()
> if not session:
>     return None

Reasonable, thanks Michael. :)
Will post the updated patch soon.

> try:
>     cmd = ...
>     s, count = ...
>     if s == 0:
>         return int(count)
>     return None
> finally:
>     session.close()
> 
> There's no need for a second 'if session' in the finally block.
> 
> >      def get_memory_size(self):
> >          """
> >          Get memory size of the VM.
> >          """
> > +        session = self.remote_login()
> > +        cmd = self.params.get("mem_chk_cmd")
> >          try:
> > -            session = self.remote_login()
> > -            if session:
> > -                cmd = self.params.get("mem_chk_cmd")
> > -                s, mem_str = session.get_command_status_output(cmd)
> > -                if s != 0:
> > -                    return None
> > -                mem = re.findall("([0-9][0-9][0-9]+)", mem_str)
> > -                mem_size = 0
> > -                for m in mem:
> > -                    mem_size += int(m)
> > -                if "GB" in mem_str:
> > -                    mem_size *= 1024
> > -                elif "MB" in mem_str:
> > -                    pass
> > -                else:
> > -                    mem_size /= 1024
> > -                return int(mem_size)
> > -            return None
> > +            s, mem_str = session.get_command_status_output(cmd)
> > +            if s != 0:
> > +                return None
> > +            mem = re.findall("([0-9][0-9][0-9]+)", mem_str)
> > +            mem_size = 0
> > +            for m in mem:
> > +                mem_size += int(m)
> > +            if "GB" in mem_str:
> > +                mem_size *= 1024
> > +            elif "MB" in mem_str:
> > +                pass
> > +            else:
> > +                mem_size /= 1024
> > +            return int(mem_size)
> >          finally:
> > -            session.close()
> > +            if session:
> > +                session.close()
> 
> The same applies to this function.
> 
> > -- 
> > 1.6.6
> > 
> > --
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