Re: [patch 3/4] This patch introduces a new oprofile sample add function (oprofile_add_ext_hw_sample)

[Heinz Graalfs <graalfs@linux.vnet.ibm.com>]

On Tue, 2011-01-04 at 16:34 +0100, Robert Richter wrote:
> On 20.12.10 08:05:44, graalfs@linux.vnet.ibm.com wrote:
> > From: graalfs@linux.vnet.ibm.com
> > 
> > This patch introduces a new oprofile sample add function (oprofile_add_ext_hw_sample)
> > that can also take task_struct as an argument, which is used by the hwsampler kernel module 
> > when copying hardware samples to OProfile buffers.
> > 
> > Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
> > Signed-off-by: Maran Pakkirisamy <maranp@linux.vnet.ibm.com>
> > Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
> > ---
> >  drivers/oprofile/cpu_buffer.c |   26 +++++++++++++++++++-------
> >  1 file changed, 19 insertions(+), 7 deletions(-)
> 
> > +void oprofile_add_ext_hw_sample(unsigned long pc, struct pt_regs * const regs,
> > +				unsigned long event, int is_kernel,
> > +				struct task_struct *task)
> > +{
> > +	__oprofile_add_ext_sample(pc, regs, event, is_kernel, task);
> > +}
> > +EXPORT_SYMBOL_GPL(oprofile_add_ext_hw_sample);
> 
> Hmm, I am not convinced of this new interface between the hwsampler
> module and oprofile. It is asymmetric and bloats the function's
> parameters list. A first simplification would be to not implement
> hwsampler as module and integrate this in oprofile. Then, we can look
> for a better way to add samples to the oprofile buffer. What do you
> think?
> 
> -Robert
> 
Robert, thanks for all the comments. I need to think and discuss this. 

-Heinz