Re: [Qemu-devel] [PATCH v3 2/9] s390x/kvm: pass values instead of pointers to kvm_s390_set_clock_*()

[Cornelia Huck <cohuck@redhat.com>]

On Mon, 25 Jun 2018 17:54:42 +0200
David Hildenbrand <david@redhat.com> wrote:

> On 25.06.2018 17:50, Cornelia Huck wrote:
> > On Mon, 25 Jun 2018 13:53:45 +0200
> > David Hildenbrand <david@redhat.com> wrote:
> >   
> >> We are going to factor out the TOD into a separate device and use const
> >> pointers for device class functions where possible. We are passing right
> >> now ordinary pointers that should never be touched when setting the TOD.
> >> Let's just pass the values directly.
> >>
> >> Signed-off-by: David Hildenbrand <david@redhat.com>
> >> ---
> >>  target/s390x/cpu.c       |  4 ++--
> >>  target/s390x/kvm-stub.c  |  4 ++--
> >>  target/s390x/kvm.c       | 12 ++++++------
> >>  target/s390x/kvm_s390x.h |  4 ++--
> >>  4 files changed, 12 insertions(+), 12 deletions(-)
> >>
> >> diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c
> >> index c268065887..68512e3e54 100644
> >> --- a/target/s390x/cpu.c
> >> +++ b/target/s390x/cpu.c
> >> @@ -413,9 +413,9 @@ int s390_set_clock(uint8_t *tod_high, uint64_t *tod_low)  
> > 
> > Any reason why you keep the pointers here?
> >   
> >>      int r = 0;
> >>  
> >>      if (kvm_enabled()) {
> >> -        r = kvm_s390_set_clock_ext(tod_high, tod_low);
> >> +        r = kvm_s390_set_clock_ext(*tod_high, *tod_low);
> >>          if (r == -ENXIO) {
> >> -            return kvm_s390_set_clock(tod_high, tod_low);
> >> +            return kvm_s390_set_clock(*tod_high, *tod_low);  
> > 
> > Especially as it would be more clean to check for !NULL before
> > dereferencing...  
> 
> See the next patch :)
> 
> (I assume that refactoring code in order to rip it out does not make sense)

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"Note that s390_set_clock() will be removed in a follow-on patch and
therefore its calling convention is not changed."