Re: [PATCH v2] random: remove batched entropy locking

[Jason A. Donenfeld]

Hi Sebastian,

On Fri, Feb 4, 2022 at 3:30 PM Sebastian Andrzej Siewior
<bigeasy@xxxxxxxxxxxxx> wrote:
> > What if we keep a spinlock_t there on PREEMPT_RT but stick with
> > disabling interrupts on !PREEMPT_RT? I wish there was a solution or an
> > API that amounted to the same thing so there wouldn't need to be an
> > #ifdef, but I don't know what that'd be.
>
> If it is still to much try to look for locallock_t and
> local_lock_irqsave(). This is kind of like your local_irq_save() but
> you have lockdep annotations and PREEMPT_RT has a spinlock_t like
> behaviour. It also documents in-code what the scope of your locking is.

Oh, that's terrific, thanks! Sounds like exactly what we were looking
for. I'll respin this patch with that.

Jason