From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <cl@linux-foundation.org>
Subject: Re: [PATCH] percpu: add optimized generic percpu accessors
Date: Wed, 28 Jan 2009 11:50:21 -0500 (EST)
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Cc: Tejun Heo <tj@kernel.org>, Ingo Molnar <mingo@elte.hu>,
	Herbert Xu <herbert@gondor.apana.org.au>,
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To: Rusty Russell <rusty@rustcorp.com.au>
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On Wed, 28 Jan 2009, Rusty Russell wrote:

> AFAICT we'll need a hybrid: HAVE_NMISAFE_CPUOPS, and if not, use atomic_t
> in ftrace (which isn't NMI safe on parisc or sparc/32 anyway, but I don't think we care).

Right.


> Other than the shouting, I liked Christoph's system:
> - CPU_INC = always safe (eg. local_irq_save/per_cpu(i)++/local_irq_restore)
> - _CPU_INC = not safe against interrupts (eg. get_cpu/per_cpu(i)++/put_cpu)
> - __CPU_INC = not safe against anything (eg. per_cpu(i)++)
>
> I prefer the name 'local' to the name 'cpu', but I'm not hugely fussed.

The term cpu is meaning multiple things at this point. So yes it may be
better to go with glibc naming of thread local space.