On Mon, Nov 09, 2015 at 05:57:25PM +0530, Vineet Gupta wrote: > From e29de8efa621b825891dcc744c84965b38f6b868 Mon Sep 17 00:00:00 2001 > From: Vineet Gupta <[email protected]> > Date: Mon, 9 Nov 2015 17:48:34 +0530 > Subject: [PATCH] ARC: cpu_relax() to be compiler barrier even for UP > > cpu_relax() on ARC has been barrier only for SMP (and no-op for UP). Per > recent discussions, it is safer to make it a compiler barrier > unconditionally. > > Link: http://lkml.kernel.org/r/[email protected]
Acked-by: Peter Zijlstra (Intel) <[email protected]> > Signed-off-by: Vineet Gupta <[email protected]> > --- > arch/arc/include/asm/processor.h | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/arch/arc/include/asm/processor.h > b/arch/arc/include/asm/processor.h > index 44545354e9e8..1d694c1ef6d6 100644 > --- a/arch/arc/include/asm/processor.h > +++ b/arch/arc/include/asm/processor.h > @@ -57,11 +57,7 @@ struct task_struct; > * A lot of busy-wait loops in SMP are based off of non-volatile data > otherwise > * get optimised away by gcc > */ > -#ifdef CONFIG_SMP > #define cpu_relax() __asm__ __volatile__ ("" : : : "memory") > -#else > -#define cpu_relax() do { } while (0) > -#endif > > #define cpu_relax_lowlatency() cpu_relax() > > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
