> On 29 Sep 2023, at 08:31, Julien Grall <[email protected]> wrote: > > Hi Stefano, > > On 29/09/2023 00:32, Stefano Stabellini wrote: >> nr_cpu_ids is unsigned int, but find_first_bit returns unsigned long (at >> least on arm). > > find_* are meant to be used by common code. So I think the first step is to > correct the return type so it is consistent across all architectures. > > I don't have a strong opinion on whether they should all return 'unsigned > long'. > > Then we can discuss if the MISRA rule is still violated. > >> Use the larger type for min_t to avoid larger-to-smaller >> type assignments. This address 141 MISRA C 10.3 violations. > > I find interesting you are saying this given that... >> Signed-off-by: Stefano Stabellini <[email protected]> >> --- >> diff --git a/xen/include/xen/cpumask.h b/xen/include/xen/cpumask.h >> index 9826707909..a6ed6a28e8 100644 >> --- a/xen/include/xen/cpumask.h >> +++ b/xen/include/xen/cpumask.h >> @@ -208,7 +208,7 @@ static inline void cpumask_copy(cpumask_t *dstp, const >> cpumask_t *srcp) >> static inline int cpumask_first(const cpumask_t *srcp) >> { >> - return min_t(int, nr_cpu_ids, find_first_bit(srcp->bits, nr_cpu_ids)); >> + return min_t(unsigned long, nr_cpu_ids, find_first_bit(srcp->bits, >> nr_cpu_ids)); > > ... cpumask_first() is return 'int'. So rather than fixing it, you seem to > have just moved the violation. > >> } >> static inline int cpumask_next(int n, const cpumask_t *srcp)
I’ve also found that find_first_bit returns: - unsigned int on x86 - unsigned long on ppc - unsigned long on arm64 - int on arm32 (seems that value is always >= 0 So maybe they can be all unsigned int, and cpumask_first can be as well unsigned int? > > Cheers, > > -- > Julien Grall >
