Re: [PATCH v2 15/19] xen/sysctl: wrap around XEN_SYSCTL_physinfo

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

On 3/27/25 10:58 AM, Jan Beulich wrote:

> On 27.03.2025 10:35, Oleksii Kurochko wrote:
> > On 3/26/25 6:50 AM, Penny Zheng wrote:
> > > The following functions are only used to deal with XEN_SYSCTL_physinfo,
> > > then they shall be wrapped:
> > > - arch_do_physinfo
> > > - get_outstanding_claims
> > >
> > > Signed-off-by: Penny Zheng<Penny.Zheng@xxxxxxx>
> > > ---
> > > v1 -> v2:
> > > - no need to wrap declaration
> > > - add transient #ifdef in sysctl.c for correct compilation
> > > ---
> > >   xen/arch/arm/sysctl.c   | 2 ++
> > >   xen/arch/riscv/stubs.c  | 2 ++
> > >   xen/arch/x86/sysctl.c   | 2 ++
> > >   xen/common/page_alloc.c | 2 ++
> > >   xen/common/sysctl.c     | 2 +-
> > >   5 files changed, 9 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/xen/arch/arm/sysctl.c b/xen/arch/arm/sysctl.c
> > > index 32cab4feff..2d350b700a 100644
> > > --- a/xen/arch/arm/sysctl.c
> > > +++ b/xen/arch/arm/sysctl.c
> > > @@ -15,6 +15,7 @@
> > >   #include <asm/arm64/sve.h>
> > >   #include <public/sysctl.h>
> > >   
> > > +#ifdef CONFIG_SYSCTL
> > >   void arch_do_physinfo(struct xen_sysctl_physinfo *pi)
> > >   {
> > >       pi->capabilities |= XEN_SYSCTL_PHYSCAP_hvm | XEN_SYSCTL_PHYSCAP_hap;
> > > @@ -22,6 +23,7 @@ void arch_do_physinfo(struct xen_sysctl_physinfo *pi)
> > >       pi->arch_capabilities |= MASK_INSR(sve_encode_vl(get_sys_vl_len()),
> > >                                          XEN_SYSCTL_PHYSCAP_ARM_SVE_MASK);
> > >   }
> > > +#endif
> > >   
> > >   long arch_do_sysctl(struct xen_sysctl *sysctl,
> > >                       XEN_GUEST_HANDLE_PARAM(xen_sysctl_t) u_sysctl)
> > > diff --git a/xen/arch/riscv/stubs.c b/xen/arch/riscv/stubs.c
> > > index 5951b0ce91..7b3f748886 100644
> > > --- a/xen/arch/riscv/stubs.c
> > > +++ b/xen/arch/riscv/stubs.c
> > > @@ -328,10 +328,12 @@ long arch_do_sysctl(struct xen_sysctl *sysctl,
> > >       BUG_ON("unimplemented");
> > >   }
> > >   
> > > +#ifdef CONFIG_SYSCTL
> > >   void arch_do_physinfo(struct xen_sysctl_physinfo *pi)
> > >   {
> > >       BUG_ON("unimplemented");
> > >   }
> > > +#endif /* CONFIG_SYSCTL */
> > >         
> > Considering that now we will have CONFIG_SYSCTL, I think it would be better just to drop
> > definition of arch_do_physinfo() from riscv/stubs.c as it was added to make common code build
> > for RISC-V happy.
> >       
> Wouldn't that require SYSCTL=n then for RISC-V, which better wouldn't be done
> (as it would need undoing later on)?
>     
I missed that SYSCTL=y by default.

Then it will be really better to have #ifdef CONFIG_SYSCTL instead of removing 
arch_do_physinfo() from riscv/stub.c. (the same is true then for arch_do_sysctl()
in the next patch)

~ Oleksii