29 Jul
2024
29 Jul
'24
5:06 p.m.
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