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Re: script from chris mason

Mike Mason wrote:

Vara Prasad wrote:

Hi Mike,

That is a good improvement from the original script but i still see use of the kernel function to probe "schedule". We should use probes from tapsets as much as possible rather than probing straight kernel functions. Don't we have schedule function already covered in one of our tapsets, if not why not. If it is there but not useful for this purpose, what should we do to improve that probe point in the tapset to be more useful including this case.

The scheduler tapset provides probes for context switches, migrations and cpu on/off, but not specifically for schedule. I agree we should encourage tapset use wherever possible, but since the tapsets don't currently have a schedule() probe, I didn't change that in the script. I'll add a schedule() probe to the tapset. It makes sense in this case because it's a common function, it's frequently called and probably of interest to many others.

That will be great.

However, this doesn't mean we can eliminate use of kernel.function all together. Some functions of interest to developers don't make sense in tapsets.

Sure we can't eliminate but we should look closely every time we use a kernel.function construct if it belongs to a tapset.


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