Re: [tip:perf/core] perf tools, Alpha: Add Alpha support to perf.h

[Pekka Enberg <penberg@cs.helsinki.fi>]

Hi Ingo,

On Mon, Oct 26, 2009 at 1:38 PM, tip-bot for Michael Cree
<mcree@orcon.net.nz> wrote:
> Commit-ID:  fcd14b3203b538dca04a2b065c774c0b57863eec
> Gitweb:     http://git.kernel.org/tip/fcd14b3203b538dca04a2b065c774c0b57863eec
> Author:     Michael Cree <mcree@orcon.net.nz>
> AuthorDate: Mon, 26 Oct 2009 21:32:06 +1300
> Committer:  Ingo Molnar <mingo@elte.hu>
> CommitDate: Mon, 26 Oct 2009 09:45:41 +0100
>
> perf tools, Alpha: Add Alpha support to perf.h
>
> For the perf tool the patch implements an Alpha specific section
> in the perf.h header file.
>
> Signed-off-by: Michael Cree <mcree@orcon.net.nz>
> Cc: Richard Henderson <rth@twiddle.net>
> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Paul Mackerras <paulus@samba.org>
> LKML-Reference: <1256545926-6972-1-git-send-email-mcree@orcon.net.nz>
> Signed-off-by: Ingo Molnar <mingo@elte.hu>
> ---
>  tools/perf/perf.h |    6 ++++++
>  1 files changed, 6 insertions(+), 0 deletions(-)
>
> diff --git a/tools/perf/perf.h b/tools/perf/perf.h
> index 8cc4623..216bdb2 100644
> --- a/tools/perf/perf.h
> +++ b/tools/perf/perf.h
> @@ -47,6 +47,12 @@
>  #define cpu_relax()    asm volatile("":::"memory")
>  #endif
>
> +#ifdef __alpha__
> +#include "../../arch/alpha/include/asm/unistd.h"
> +#define rmb()          asm volatile("mb" ::: "memory")
> +#define cpu_relax()    asm volatile("" ::: "memory")
> +#endif

OK, I'll bite. We tell userspace developers not to include kernel
headers. Why is it okay for perf to do it (especially for something
that's in asm)?

                        Pekka