Re: [PATCH] oprofile: Allow setting EDGE/INV/CMASK for Intelcounter events

From: Robert Richter
Date: Wed Mar 16 2011 - 11:46:12 EST


On 16.03.11 11:27:57, Andi Kleen wrote:
> > I would like to write the actual value back so that userland may read
> > it:
> >
> > counter_config->extra &= (ARCH_PERFMON_EVENTSEL_INV|
> > ARCH_PERFMON_EVENTSEL_EDGE|
> > ARCH_PERFMON_EVENTSEL_CMASK);
> > val |= counter_config->extra;
> >
> > The value will not be updated emmediately but at least after profiling
> > was started.
>
> Okay.
>
> >
> > As an alternative, maybe we better put this extra bits in the
> > unit_mask, e.g. in bits [31:16] of the unit mask for bits [31:16] of
> > PerfEvtSel? Then, we simply could use the current userland to set it
> > up.
>
> We can't anyways, it doesn't support it.

Shouldn't something like the follwing work (assuming the umask table
is modified)?

opcontrol --event SOME_EVENT:100000:0x00800000 ...

(setting the INV flag)

-Robert

--
Advanced Micro Devices, Inc.
Operating System Research Center

--
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/