[PATCH v3 1/5] event/opdl: fix non-constant compile time assertion

[Bruce Richardson]

On Wed, Jan 17, 2024 at 10:58:12AM +0300, Andrew Rybchenko wrote:
> On 1/16/24 21:41, Stephen Hemminger wrote:
> > RTE_BUILD_BUG_ON() was being used with a non-constant value.
> > The inline function rte_is_power_of_2() is not constant since
> > inline expansion happens later in the compile process.
> > Replace it with macro which will be constant.
> > 
> > Fixes: 4236ce9bf5bf ("event/opdl: add OPDL ring infrastructure library")
> > Cc: liang.j.ma at intel.com
> > Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
> > Acked-by: Bruce Richardson <bruce.richardson at intel.com>
> > Acked-by: Tyler Retzlaff <roretzla at linux.microsoft.com>
> > ---
> >   drivers/event/opdl/opdl_ring.c | 5 ++++-
> >   1 file changed, 4 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/event/opdl/opdl_ring.c b/drivers/event/opdl/opdl_ring.c
> > index 69392b56bbec..24e0bbe3222d 100644
> > --- a/drivers/event/opdl/opdl_ring.c
> > +++ b/drivers/event/opdl/opdl_ring.c
> > @@ -31,6 +31,9 @@
> >   #define OPDL_OPA_MASK    (0xFF)
> >   #define OPDL_OPA_OFFSET  (0x38)
> > +/* Equivalent to rte_is_power_of_2() but as macro. */
> > +#define IS_POWER_OF_2(x) (((x) & ((x) - 1)) == 0)
> 
> IMHO adding it in specific driver is a wrong direction. I'm afraid it
> will result in duplication of such macros in code base without clear
> reason why.
> 
> May be it is better to add it with a proper name to EAL?
> 
+1
Even if it's a lower-case name, lets make it a macro in EAL so we can use
it everywhere in asserts.