Re: [PATCH 1/2] perf/x86: update Haswell PEBS event constraints

From: Andi Kleen
Date: Thu Jun 19 2014 - 16:18:11 EST


> I don't quite understand that.
> You need to know which events support PEBS. You need a table

We're talking about the kernel allowing things here.
Yes the user still needs to know what supports PEBS, but
that doesn't concern the kernel.

You can just allow it for all, it's a nop if the event doesn't
support it. And also the fields like DataLA are simply 0 when
not supported.

The only thing you need is a rule to limit to 4 counters.

Then only cases that are special (PREC_DIST, extra registers)
would need to be handled explicitely.

-Andi
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/