Re: [PATCH 1/4] tracing: Use the perf recursion protection fromtrace event

[Peter Zijlstra]

On Sun, 2009-11-22 at 12:22 +0100, Ingo Molnar wrote:

> > > +void perf_swevent_put_recursion_context(int *recursion)
> > >  {
> > > -       struct perf_cpu_context *cpuctx = &get_cpu_var(perf_cpu_context);
> > > -       int *recursion = perf_swevent_recursion_context(cpuctx);
> > > -       struct perf_event_context *ctx;
> > > -
> > > -       if (*recursion)
> > > -               goto out;
> > > +       (*recursion)--;
> > > +}
> > 
> > And here as well.
> 
> Global functions are in essence a barrier() to GCC but yeah.

Can't rely on that, because if the thing decides to inline this function
it looses that barrier semantic.

And it being such a small function with a few callsites in the same
translation unit, there's a fair chance it will actually inline.

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