Re: [PATCH v1] ASoC: meson: axg-fifo: set option to use raw spinlock

Jerome Brunet
2024-07-29T15:06:53Z

On Mon 29 Jul 2024 at 15:44, Mark Brown <broonie@kernel.org> wrote:

> On Mon, Jul 29, 2024 at 04:15:31PM +0200, Jerome Brunet wrote:
>
>> Maybe mmio regmap should '.use_raw_spinlock = true' by default when
>> '.fast_io' is set ?
>
>> Mark, what is your opinion on this ? I guess it is not the first time
>> this occurs ?
>
> I don't recall this coming up much TBH. It may be that people just set
> raw spinlocks when they need it, or that there's not many people using
> relevant devices with RT kernels.

I have not been playing much with RT TBH, but AFAIK, with RT irq
handlers are threaded unless IRQF_NO_THREAD is set. In this case,
something preemptible in the handler should not be a problem.

The axg-fifo drivers do not have IRQF_NO_THREAD so something is a bit
unclear here.

--
Jerome