Re: [rfc/patch] mm/slub: restore/expand unfreeze_partials() local exclusion scope

From: Vlastimil Babka
Date: Sun Jul 25 2021 - 15:34:58 EST


On 7/25/21 9:12 PM, Vlastimil Babka wrote:
> + /*
> + * On !RT we just want to disable preemption, on RT we need the lock
> + * for real. This happens to match local_lock() semantics.
> + */
> + local_lock(&s->cpu_slab->lock);

OK I realized (and tglx confirmed) that this will blow up on !RT +
lockdep if interrupted by ___slab_alloc() that will do
local_lock_irqsave(). So back to #ifdefs it is. But should work as-is
for RT testing.