Re: [PATCH] iommu: replace single-char identifiers in macros

From: Qian Cai
Date: Mon Jun 03 2019 - 09:33:21 EST


On Mon, 2019-06-03 at 14:07 +0100, Robin Murphy wrote:
> On 03/06/2019 13:59, Qian Cai wrote:
> > There are a few macros in IOMMU have single-char identifiers make the
> > code hard to read and debug. Replace them with meaningful names.
> >
> > Suggested-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Qian Cai <cai@xxxxxx>
> > ---
> > Â include/linux/dmar.h | 14 ++++++++------
> > Â 1 file changed, 8 insertions(+), 6 deletions(-)
> >
> > diff --git a/include/linux/dmar.h b/include/linux/dmar.h
> > index f8af1d770520..eb634912f475 100644
> > --- a/include/linux/dmar.h
> > +++ b/include/linux/dmar.h
> > @@ -104,12 +104,14 @@ static inline bool dmar_rcu_check(void)
> > ÂÂ
> > Â #define dmar_rcu_dereference(p) rcu_dereference_check((p),
> > dmar_rcu_check())
> > ÂÂ
> > -#define for_each_dev_scope(a, c, p, d) \
> > - for ((p) = 0; ((d) = (p) < (c) ? dmar_rcu_dereference((a)[(p)].dev)
> > : \
> > - NULL, (p) < (c)); (p)++)
> > -
> > -#define for_each_active_dev_scope(a, c, p, d) \
> > - for_each_dev_scope((a), (c), (p), (d)) if (!(d)) { continue;
> > } else
> > +#define for_each_dev_scope(devs, cnt, i, tmp)
> > \
> > + for ((i) = 0; ((tmp) = (i) < (cnt) ?
> > \
>
> Given that "tmp" actually appears to be some sort of device cursor, I'mÂ
> not sure that that naming really achieves the stated goal of clarity :/

"tmp" is used in the callers everywhere though, although I suppose something
like "tmp_dev" can be used if you prefer.