Re: [PATCH v5 01/51] x86/apic: Provide helpers to set local APIC timer period in hz and khz

[Sean Christopherson]

On Thu, Jul 02, 2026, Michael Kelley wrote:
> > @@ -796,6 +796,16 @@ bool __init apic_needs_pit(void)
> >  	return lapic_timer_period == 0;
> >  }
> > 
> > +void apic_set_timer_period_khz(u64 period_khz, const char *source)
> > +{
> > +	lapic_timer_period = mul_u64_u32_div(period_khz, 1000, HZ);
> > +}
> > +
> > +void apic_set_timer_period_hz(u64 period_hz, const char *source)
> > +{
> > +	lapic_timer_period = div_u64(period_hz, HZ);
> > +}
> 
> A string "source" argument is passed in, but not used. Is there an
> envisioned future use? Also, this function doesn't output a pr_info()
> message like the existing Hyper-V and VMware code does. 

It was a complete goof on my part (Sashiko also pointed out the oddity[*]).  I
fully intended to log a message and provide equivalent Hyper-V/VMware behavior,
and totally spaced it.

[*] https://lore.kernel.org/all/20260701194621.4BD691F000E9@xxxxxxxxxxxxxxx

> I don't know that the message is all that useful, though I do remember one
> case where I was debugging some clock/timer issue when I looked at it.