Re: [PATCH] add i386 idle notifier (take 3)

[Stephane Eranian <eranian@hpl.hp.com>]

Adrian,

On Thu, Jan 04, 2007 at 12:07:08AM +0100, Adrian Bunk wrote:
> > I am hearing conflicting opinions on this one.
> > 
> > Perfmon is a fairly big patch. It is hard to take it as one. I have tried to
> > split it up in smaller, more manageable pieces as requested by top-level
> > maintainers. This process implies that I supply small patches which may not
> > necessarily have users just yet.
> 
> There should be a big patchset consisting of manageable pieces, if 
> possible all of it in -mm.
> 

I have already split up the pieces: generic vs. per-arch. I have also
divided it between modified vs. new files. It becomes harder to go
much beyond that without creating also one patch per modified file.

> > > The unused x86-64 idle notifiers are now bloating the kernel since 
> > > nearly one year.
> > > 
> > > > > And why does it bloat the kernel with EXPORT_SYMBOL's although even your 
> > > > > perfmon-new-base-061204 doesn't seem to add any modular user?
> > > > 
> > > Where does the perfmon code use the EXPORT_SYMBOL's?
> > 
> > The perfmon patch includes several kernel modules which make use of
> > the exported entry points. The following symbols are exported:
> > 
> > pfm_pmu_register/pfm_pmu_unregister:
> > 	* PMU description module registration.
> > 	* Used to describe PMU model.
> > 	* Used by perfmon_p4.c, perfmon_core.c, perfmon_mckinley.c, and others
> > 
> > pfm_fmt_register/pfm_fmt_unregister:
> > 	* Sampling format module registration
> > 	* Used by perfmon_dfl_smpl.c, perfmon_pebs_smpl.c
> > 
> > pfm_interrupt_handler:
> > 	* PMU interrupt handler
> > 	* Used by MIPS-specific perfmon code
> > 
> > pfm_pmu_conf/pfm_controls:
> > 	* global state/control variable
> > 
> > All exported symbols are currently used. Why are you saying this adds bloat?
> 
> Which module uses idle_notifier_register/idle_notifier_unregister?
> 
None.

I have no issue with removing the EXPORT_SYMBOL on i386 and x86_64 if you
think that would help.

-- 
-Stephane