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Re: script from chris mason
Mike Mason wrote:
Vara Prasad wrote:
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.