Re: [PATCH] tracing/irqtrace: only call trace_hardirqs_on/off when state changes

From: Joel Fernandes
Date: Wed Jul 11 2018 - 01:58:16 EST


On Tue, Jul 10, 2018 at 09:44:57PM -0400, Steven Rostedt wrote:
> On Wed, 2 May 2018 10:12:14 +1000
> Nicholas Piggin <npiggin@xxxxxxxxx> wrote:
>
> > > I have mixed feelings about this patch, I am Ok with this patch but I
> > > suggest its sent with the follow-up patch that shows its use of this.
> > > And also appreciate if such a follow-up patch is rebased onto the IRQ
> > > tracepoint work: https://patchwork.kernel.org/patch/10373129/
> > >
> > > What do you think?
> >
> > I'll try to dig it up and resend. Thanks for the feedback on it.
>
> Joel,
>
> With your latest patches, is this obsolete?

Yes, that's right. This patch isn't needed for what I was doing (improving
the performance of the irq disable/enable path). I didn't see any performance
improvement with this patch. Instead, the patches in my series use SRCU to
improve the performance of the tracepoints.

thanks,

- Joel