Re: [PATCH 01/02] cpuset bitmap and mask remap operators

[Paul Jackson <pj@sgi.com>]

Andrew wrote:
> >  +#define node_remap(oldbit, old, new) \
> >  +		__node_remap((oldbit), &(old), &(new), MAX_NUMNODES)
> >  +static inline int __node_remap(int oldbit, ...
>
> What's the reason for the wrapper macro?

Most all the nodemask/cpumask operators are like that.  It allows
writing *mask code as if masks were pass by value (which is how the
vast majority of kernel hackers, working on systems with one-word
masks, think of them), while actually passing by reference, to
avoid unnecessary stack copies of multiword masks.


> +EXPORT_SYMBOL(bitmap_bitremap);
> 
> Is that deliberately not EXPORT_SYMBOL_GPL?

It's not deliberate that I am aware of.

But it does seem to be the common practice ....

All the bitmap routines are that way - no GPL.  In fact it seems that
almost all the EXPORT_SYMBOLS in the lib/*.c routines are that way - 12
with GPL and 174 without GPL, or some such.  The only lib/*.c GPL
exports are in lib/klist.c and lib/kobject_uevent.c.

Is this bad?

-- 
                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <pj@sgi.com> 1.925.600.0401