Re: [PATCH] Break out types from <linux/list.h> to <linux/list_types.h>.

[Alexey Dobriyan <adobriyan@gmail.com>]

On Fri, Jul 02, 2010 at 02:48:17PM -0600, Matthew Wilcox wrote:
> On Fri, Jul 02, 2010 at 03:33:52PM -0400, Chris Metcalf wrote:
> > On 7/2/2010 3:19 PM, Matthew Wilcox wrote:
> > > Why a new header file instead of linux/types.h?
> > 
> > I was working from analogy to kvm_types.h, mm_types.h, rwlock_types.h,
> > spinlock_types.h.  My impression is that linux/types.h is generally for
> > basic (non-struct) types, with atomic_t/atomic64_t being added as
> > "almost non-struct types", and of course the historical exception of
> > "struct ustat", which has been there since the dawn of time (0.97 anyway).
> 
> I think list_head, hlist_head and hlist_node qualify as "almost non-struct
> types", don't you?  :-)
> 
> I wouldn't mind seeing kvm_types.h, rwlock_types.h

> and spinlock_types.h

*cough*

You may want to run spinlock_types.h through preprocessor and see how
much garbage it will produce.

> merged into types.h, personally.  They're all pretty fundamental kernel
> kind of types.

Also we care about compilation speed.

> It's a matter of taste, and I'm not particularly fussed one way or the other.
> 
> mm_types.h is complex and full of mm-specific information, so keeping
> it separate makes sense to me.
> 
> I just object to the unnecessary creation of tiny files like this.

Me too. Also jumping over one file to understand what's going on is
better than jumping over multiple files.

> Which is how we ended up with atomic_t and atomic64_t in there in the
> first place :-)