On Apr 18, 2:14pm, christoph_eg...@gmx.de (Christoph Egger) wrote: -- Subject: Re: CVS commit: src/sys/uvm
| Christos Zoulas wrote: | > On Apr 18, 1:46pm, christoph_eg...@gmx.de (Christoph Egger) wrote: | > -- Subject: Re: CVS commit: src/sys/uvm | > | > | This would imply to change the flags arguments of the pmap API | > | from int to u_int to avoid troubles with checking flag bits. | > | > As it should have been in the first place, so change it. | | May I propose to introduce a MI flags_t for this purpose? | | I would define it as | | typedef u_int flags_t; | | If this is fine, is sys/sys/types.h the right place ? | If yes, should it be available in _KERNEL, in _NETBSD_SOURCE or | generally ? I am not sure I'd go that far but this is more for a discussion in tech-kern. The reason I am saying this is that we have used different width flags depending on the number of bits needed or the number of bytes that are available in a struct. It is also nice to explicitly know the number of bits in the flags argument (which is more important for long than int I guess since we don't have ILP64 systems). There is also the issue of namespace pollution, so defining flags_t and using it is problematic because it would have to be namespace protected. For those reasons I say make it u_int for now, and start a discussion in tech-kern. | > | > | Alternatively, code like this | > | | > | if (flags & FLAG1) | > | do_something(); | > | | > | must be converted to | > | | > | if ((flags & FLAG1) == FLAG1) | > | do_something(); | > | > This is overkill. | | and error-prone as it is very likely to be | forgotten. | | Just wanted to mention the alternative for completeness. Yes, that is right, I agree. christos
