Re: [thisops uV3 08/18] Taskstats: Use this_cpu_ops

From: Christoph Lameter
Date: Tue Dec 07 2010 - 09:39:16 EST


On Mon, 6 Dec 2010, Balbir Singh wrote:

> > Correct. We need to subtract one from that (which will eliminate the minus
> > -1 that the inline this_cpu_inc_return creates).
> >
>
> But that breaks current behaviour, we should probably initialize all
> of the array to -1?

Not necessary. This_cpu_inc() uses an xadd instruction which retrieves
the value and then increments the memory location. Then it adds 1. The -1
eliminates that add.
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