David Hildenbrand <david@xxxxxxxxxx> writes: > On 09.09.20 09:17, Greg Kroah-Hartman wrote: >> On Tue, Sep 08, 2020 at 10:10:08PM +0200, David Hildenbrand wrote: >>> We soon want to pass flags, e.g., to mark added System RAM resources. >>> mergeable. Prepare for that. >> >> What are these random "flags", and how do we know what should be passed >> to them? >> >> Why not make this an enumerated type so that we know it all works >> properly, like the GPF_* flags are? Passing around a random unsigned >> long feels very odd/broken... > > Agreed, an enum (mhp_flags) seems to give a better hint what can > actually be passed. Thanks! You probably know this but ... Just using a C enum doesn't get you any type safety. You can get some checking via sparse by using __bitwise, which is what gfp_t does. You don't actually have to use an enum for that, it works with #defines also. Or you can wrap the flag in a struct, the way atomic_t does, and then the compiler will prevent passing plain integers in place of your custom type. cheers
