On Mon, 25 Sep 2017 12:32:23 +0200 Peter Zijlstra <pet...@infradead.org> wrote:
> > You mean you want to trace all calls to preempt and irq off even if > > preempt and irqs are already off? > > Sure, why not? This stuff naturally nests, and who is to say its not a > useful thing to trace all of them? > > By also tracing the nested sections you can, for instance, see how much > you'd really win by getting rid of the outer one. If, for instance, the > outer only accounts for 1% of the time, while the inner ones are > interlinked and span the other 99%, there's more work to do than if that > were not the case. If we do this we need a field to record if the preemption or irqs were toggled by that call. Something that filters could easily be added to only show what this patch set has. -- Steve
