From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anurup M <anurupvasu@gmail.com>
Subject: Help needed. Default value for a event parameter (param=?)
Date: Tue, 26 Apr 2016 19:00:40 +0530
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I have a question about perf event parameter. I am trying to add an event parameter
which should take a default value if not input by the user.

I have the event added in sys/bus/event_source/devices/<pmu>/events/  and there
is a configurable event parameter "unit=?"
ex: event=0x301,units=?

The perf list list it as below
# perf list
<pmu>/<event_alias>,units=?/ [Kernel PMU event]

Now I have a requirement that If user does not pass any value for the parameter "unit"
I should take a default value in my PMU implementation. Is this supported?

If not please guide me on where the change is needed.
Any suggestions are appreciated.

Thanks,
Anurup