[PATCH 3/5] KVM: arm64: Rename __vcpu_sys_reg -> vcpu_sys_reg

[Marc Zyngier]

Hi Alex,

On Wed, 14 Jul 2021 10:55:59 +0100,
Alexandru Elisei <alexandru.elisei at arm.com> wrote:
> 
> There are two macros to access a specific system register from a known
> kvm_cpu_context: __ctxt_sys_reg(), which returns a pointer to the register,
> and ctxt_sys_reg(), which deferences the pointer returned by
> __ctxt_sys_reg().
> 
> __vcpu_sys_reg() serves a similar purpose, with the difference being that
> it takes a struct kvm_vcpu as a parameter. __vcpu_sys_reg(), although it
> looks like __ctxt_sys_reg(), it dereferences the pointer to the register,
> like ctxt_sys_reg() does, and indeed it is defined as an abstraction over
> ctxt_sys_reg().
> 
> Let's remove this naming inconsistency by renaming __vcpu_sys_reg() to
> vcpu_sys_reg(), to make it clear it behaves like ctxt_sys_reg(), and not
> like __ctxt_sys_reg().

I can't say I'm keen on this change.

The leading underscores really are there to outline that *this is
dangerous*, as you really need to know which context you are in.
Dropping the leading '__' may give the false impression that this is
safe, and not actually a primitive that requires careful thinking
before use.

ctxt_sys_reg() is, on the other hand, clearly something that acts
solely on memory because it takes a context structure, and not a
vcpu. At least that's what the 'ctxt' prefix is supposed to convey
(not very successfully, apparently).

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.