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

[Robert Richter <robert.richter@amd.com>]

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

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Advanced Micro Devices, Inc.
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