Re: [PATCH] x86: Clean up mwait_play_dead

From: H. Peter Anvin
Date: Wed Apr 13 2011 - 12:53:33 EST


On 04/13/2011 09:11 AM, Frank Arnold wrote:
> From: Frank Arnold <frank.arnold@xxxxxxx>
>
> Commit 93789b32dbf355e70f18b17a82e8661677a7f7fb introduced
> cpuinfo_x86 *c for brevity. It is used to check for the
> mwait feature flag. The same can be done with a subsequent
> check for clflsh and save us a second per-cpu pointer
> dereference.
>
> Signed-off-by: Frank Arnold <frank.arnold@xxxxxxx>
> Acked-by: Borislav Petkov <borislav.petkov@xxxxxxx>
> ---
> arch/x86/kernel/smpboot.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>

This should be using this_cpu_has()... if that's not in the tree yet we
should add it.

Creating an absolute pointer for a percpu references is a big lose.

-hpa

--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

--
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/