Re: [PATCH v7 04/19] xen: introduce generic non-atomic test_*bit()

[Oleksii <oleksii.kurochko@xxxxxxxxx>]

On Thu, 2024-04-04 at 18:12 +0200, Jan Beulich wrote:
> On 04.04.2024 17:45, Oleksii wrote:
> > On Thu, 2024-04-04 at 15:22 +0200, Jan Beulich wrote:
> > > On 03.04.2024 12:19, Oleksii Kurochko wrote:
> > > > --- a/xen/include/xen/bitops.h
> > > > +++ b/xen/include/xen/bitops.h
> > > > @@ -65,10 +65,164 @@ static inline int generic_flsl(unsigned
> > > > long
> > > > x)
> > > >   * scope
> > > >   */
> > > >  
> > > > +#define BITOP_BITS_PER_WORD 32
> > > > +/* typedef uint32_t bitop_uint_t; */
> > > > +#define bitop_uint_t uint32_t
> > > 
> > > So no arch overrides permitted anymore at all?
> > Not really, I agree that it is ugly, but I expected that arch will
> > use
> > undef to override.
> 
> Which would be fine in principle, just that Misra wants us to avoid
> #undef-s
> (iirc).
Could you please give me a recommendation how to do that better?

The reason why I put this defintions before inclusion of asm/bitops.h
as RISC-V specific code uses these definitions inside it, so they
should be defined before asm/bitops.h; other option is to define these
definitions inside asm/bitops.h for each architecture.

> 
> > > >  /*
> > > >   * Find First Set bit.  Bits are labelled from 1.
> > > >   */
> > > 
> > > This context suggests there's a dependency on an uncommitted
> > > patch.
> > > Nothing
> > > above says so. I guess you have a remark in the cover letter, yet
> > > imo
> > > that's
> > > only partly helpful.
> > Is it really a hard dependency?
> > The current patch series really depends on ffs{l}() and that was
> > mentioned in the cover letter ( I'll reword the cover letter to
> > explain
> > why exactly this dependency is needed ), but this patch isn't
> > really
> > depends on Andrew's patch series, where ffs{l}() are introduced.
> 
> If anyone acked this patch, and if it otherwise looked independent,
> it would
> be a candidate for committing. Just that it won't apply for a non-
> obvious
> reason.
I didn't think about the it won't apply. In this I have to definitely
mention this moment in cover letter. Thanks.

~ Oleksii