On 06/05/2024 12:15, Oleksii Kurochko wrote:
>
>
> The mentioned macros exist only because of Linux compatible purpose.
>
> The patch defines __ffs() in terms of Xen bitops and it is safe
> to define in this way ( as __ffs() - 1 ) as considering that __ffs()
> was defined as __builtin_ctzl(x), which has undefined behavior when x=0,
> so it is assumed that such cases are not encountered in the current code.
>
> To not include <xen/linux-compat.h> to Xen library files __ffs() and __ffz()
> were defined locally in find-next-bit.c.
>
> Except __ffs() usage in find-next-bit.c only one usage of __ffs() leave
> in smmu-v3.c. It seems that it __ffs can be changed to ffsl(x)-1 in
> this file, but to keep smmu-v3.c looks close to linux it was deciced just
> to define __ffs() in xen/linux-compat.h and include it in smmu-v3.c
>
> Signed-off-by: Oleksii Kurochko <oleksii.kuroc...@gmail.com>
> Acked-by: Shawn Anastasio <sanasta...@raptorengineering.com>
> Reviewed-by: Jan Beulich <jbeul...@suse.com>
Acked-by: Michal Orzel <michal.or...@amd.com>
~Michal
