Re: [PATCH v6] softirq: Preserve interrupt context during IRQ exit

[Steven Rostedt]

On Thu, 15 Oct 2026 08:32:12 +0200
Karl Mehltretter <kmehltretter@xxxxxxxxx> wrote:

> On Wed, Oct 14, 2026 at 12:05:24PM +0100, Steven Rostedt wrote:
> > LGTM.
> > 
> > So this handles the transition between hard irq and softirq?
> > 
> > I wish there was a way to get preempt count updated earlier on entering a
> > hard irq so I can get rid of the transition bit in the trace recursion. As
> > there's still places that can trigger a trace in the hard irq before
> > preempt count is updated.
> >   
> 
> Yes, this handles the hardirq-to-softirq transition on IRQ exit.
> 
> I am looking into whether the preempt count can be updated before any
> traceable code can run, as a potential follow-up RFC.


I went down that path before, and the goblins there made me retreat ;-)
(I ran out of time to kill all the goblins)

> 
> If that works, it may allow the transition bit to be removed from trace
> recursion.

I would LOVE that!

-- Steve