Messages in this thread | | | Date | Wed, 15 Dec 2010 00:00:01 +0100 | From | Jonathan Neuschäfer <> | Subject | Re: [PATCH] arch/arm/kernel: use cpu_relax() in halt loops |
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On Tue, Dec 14, 2010 at 10:51:26PM +0000, Russell King - ARM Linux wrote: > On Tue, Dec 14, 2010 at 11:48:48PM +0100, Jonathan Neuschäfer wrote: > > Looking throught arch/arm/kernel/ I found some halt loops. > > I just thought we could save some power here using cpu_relax(), > > or am I missing something? > > #if __LINUX_ARM_ARCH__ == 6 > #define cpu_relax() smp_mb() > #else > #define cpu_relax() barrier() > #endif > > IOW, it's either a memory barrier or compiler barrier on ARM; it > doesn't do any power saving.
Okay, thanks for that explanation. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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