Re: [PATCH] x86/cpufeature: guard asm_volatile_goto usage with CC_HAVE_ASM_GOTO

Peter Zijlstra
2018-04-14T10:11:34Z

On Fri, Apr 13, 2018 at 01:42:14PM -0700, Alexei Starovoitov wrote:
> On 4/13/18 11:19 AM, Peter Zijlstra wrote:
> > On Tue, Apr 10, 2018 at 02:28:04PM -0700, Alexei Starovoitov wrote:
> > > Instead of
> > > #ifdef CC_HAVE_ASM_GOTO
> > > we can replace it with
> > > #ifndef __BPF__
> > > or some other name,
> >
> > I would prefer the BPF specific hack; otherwise we might be encouraging
> > people to build the kernel proper without asm-goto.
> >
>
> I don't understand this concern.

The thing is; this will be a (temporary) BPF specific hack. Hiding it
behind something that looks 'normal' (CC_HAVE_ASM_GOTO) is just not
right.