Re: [PATCH 3/3] intel_idle: add C0.2 state for Sapphire Rapids Xeon

[Peter Zijlstra <peterz@infradead.org>]

On Tue, Mar 07, 2023 at 01:39:09PM +0100, Rafael J. Wysocki wrote:
> On Mon, Mar 6, 2023 at 4:32 PM Peter Zijlstra <peterz@infradead.org> wrote:
> >
> > On Mon, Mar 06, 2023 at 02:34:18PM +0200, Artem Bityutskiy wrote:
> > > @@ -225,6 +229,27 @@ static __cpuidle int intel_idle_s2idle(struct cpuidle_device *dev,
> > >       return 0;
> > >  }
> > >
> > > +/**
> > > + * intel_idle_umwait_irq - Request C0.x using the 'umwait' instruction.
> > > + * @dev: cpuidle device of the target CPU.
> > > + * @drv: cpuidle driver (assumed to point to intel_idle_driver).
> > > + * @index: Target idle state index.
> > > + *
> > > + * Request C0.1 or C0.2 using 'umwait' instruction with interrupts enabled.
> > > + */
> > > +static __cpuidle int intel_idle_umwait_irq(struct cpuidle_device *dev,
> > > +                                        struct cpuidle_driver *drv,
> > > +                                        int index)
> > > +{
> > > +     u32 state = flg2MWAIT(drv->states[index].flags);
> > > +
> > > +     raw_local_irq_enable();
> > > +     umwait_idle(rdtsc() + umwait_limit, state);
> > > +     local_irq_disable();
> > > +
> > > +     return index;
> > > +}
> >
> > Bad copy paste job there...
> >
> > vmlinux.o: warning: objtool: intel_idle_umwait_irq+0x8c: call to trace_hardirqs_off() leaves .noinstr.text section
> 
> Well, it would be kind of nice to say that this is related to commit
> 6d9c7f51b1d9 ("cpuidle, intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE
> *again*") that is present in 6.3-rc1.

Right, but he said the patches were based on -next, which would've had
that commit for a fair while too.