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

[Christoph Lameter]

On Wed, 1 Dec 2010, Michael Holzheu wrote:

> >  		return -ENOMEM;
> >
> >  	if (!info) {
> > -		int seq = get_cpu_var(taskstats_seqnum)++;
> > -		put_cpu_var(taskstats_seqnum);
> > +		int seq = this_cpu_inc_return(taskstats_seqnum);
>
> Hmmm, wouldn't seq now always be one more than before?
>
> I think that "seq = get_cpu_var(taskstats_seqnum)++" first assigns
> taskstats_seqnum to seq and then increases the value in contrast to
> this_cpu_inc_return() that returns the already increased value, correct?

Correct. We need to subtract one from that (which will eliminate the minus
-1 that the inline this_cpu_inc_return creates).

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