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

Mark Brown
2024-07-29T15:29:02Z

[-- Attachment #1: Type: text/plain, Size: 961 bytes --]

On Mon, Jul 29, 2024 at 05:06:50PM +0200, Jerome Brunet wrote:
> On Mon 29 Jul 2024 at 15:44, Mark Brown <broonie@kernel.org> wrote:

> > 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.

Yeah, it's definitely likely to happen all the time for people using RT
with relevant devices. I'm not sure I have a good sense of if it's
likely to be a nasty surprise to switch raw spinlocks on by default when
it's currently controllable, I'd expect it'll generally be fine but it's
possibly a bit rude to any users that don't use interrupts...

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]