Re: [PATCH 3/6] x86: Allow the user not to build hw_breakpoints

From: Ingo Molnar
Date: Thu Jul 21 2011 - 03:27:47 EST



* H. Peter Anvin <hpa@xxxxxxxxx> wrote:

> On 07/14/2011 08:03 AM, Frederic Weisbecker wrote:
> > So that hw_breakpoints and perf can be not built on
> > specific embedded systems.
>
> I want to emphasize I am very, very unhappy about this. It should
> be possible to not build perf while still have breakpoints
> available... breakpoints are way more important than perf.

What we could indeed do is to separate out a 'core perf' portion that
is necessary for hw-breakpoints to work fine, thus allowing for
example the PMU drivers to be disabled.

Otherwise we have expressed hw breakpoint APIs via perf events and
that model is working well. Making hw-breakpoints a separate
subsystem again with isolated (and partly duplicated) infrastructure
would be a step back really.

Thanks,

Ingo
--
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/