On Wed, 26 Jul 2017 12:23:56 -0700 Matthias Kaehlcke <[email protected]> wrote:
> In multiple instances enum values of an incorrect type are passed to > mod_memcg_state() and other memcg functions. Apparently this is > intentional, however clang rightfully generates tons of warnings about > the mismatched types. Cast the offending values to the type expected > by the called function. The casts add noise, but this seems preferable > over losing the typesafe interface or/and disabling the warning. > > ... > > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -576,7 +576,7 @@ static inline void __mod_lruvec_state(struct lruvec > *lruvec, > if (mem_cgroup_disabled()) > return; > pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec); > - __mod_memcg_state(pn->memcg, idx, val); > + __mod_memcg_state(pn->memcg, (enum memcg_stat_item)idx, val); > __this_cpu_add(pn->lruvec_stat->count[idx], val); > } __mod_memcg_state()'s `idx' arg can be either enum memcg_stat_item or enum memcg_stat_item. I think it would be better to just admit to ourselves that __mod_memcg_state() is more general than it appears, and change it to take `int idx'. I assume that this implicit cast of an enum to an int will not trigger a clang warning?
