Re: [RFC: 2.6 patch] build kernel/profile.o only when requested

[Andrew Morton <akpm@linux-foundation.org>]

On Tue, 20 May 2008 13:21:50 +0300 Adrian Bunk <bunk@kernel.org> wrote:

> On Tue, May 20, 2008 at 02:01:21AM -0700, Andrew Morton wrote:
> > On Tue, 20 May 2008 00:53:06 +0300 Adrian Bunk <bunk@kernel.org> wrote:
> > 
> > > Build kernel/profile.o only if CONFIG_PROFILING is enabled.
> > > 
> > > This makes CONFIG_PROFILING=n kernels smaller.
> > > 
> > > As a bonus, some profile_tick() calls and one branch from schedule() are 
> > > now eliminated with CONFIG_PROFILING=n (but I doubt these are
> > > measurable effects).
> > > 
> > > This patch changes the effects of CONFIG_PROFILING=n, but I don't think 
> > > having more than two choices would be the better choice.
> > > 
> > > This patch also adds the name of the first parameter to the prototypes 
> > > of profile_{hits,tick}() since I anyway had to add them for the dummy 
> > > functions.
> > > 
> > 
> > Little nits:
> > 
> > > index 05c1cc7..4081fa3 100644
> > > --- a/include/linux/profile.h
> > > +++ b/include/linux/profile.h
> > > @@ -8,8 +8,6 @@
> > >  
> > >  #include <asm/errno.h>
> > >  
> > > -extern int prof_on __read_mostly;
> > > -
> > >  #define CPU_PROFILING	1
> > >  #define SCHED_PROFILING	2
> > >  #define SLEEP_PROFILING	3
> > > @@ -19,14 +17,29 @@ struct proc_dir_entry;
> > >  struct pt_regs;
> > >  struct notifier_block;
> > >  
> > > +#if defined(CONFIG_PROFILING) && defined(CONFIG_PROC_FS)
> > > +void create_prof_cpu_mask(struct proc_dir_entry *);
> > 
> > This omits the argument's name, whereas elsewhere you have taken care
> > to introduce the name where it was missing.
> > 
> > > +#else
> > > +#define create_prof_cpu_mask(x)			do { (void)(x); } while (0)
> > 
> > I think this could be a static inline, which is neater.
> >...
> 
> In these two cases I only moved code.
> 
> And I actually moved the other code and git just decided to move the 
> code that stayed instead since it creates less changed lines...

umm, you also changed the declarations of profile_tick() and
profile_hits() but not of create_prof_cpu_mask().

Oh well, I'll do it.