Re: [PATCH] mm: slub: annotate kmem_cache_node->list_lock as raw_spinlock

From: Peter Zijlstra
Date: Wed Apr 12 2023 - 08:50:53 EST


On Wed, Apr 12, 2023 at 03:30:20PM +0800, Qi Zheng wrote:
> Maybe we should make CONFIG_PROVE_RAW_LOCK_NESTING depend on
> CONFIG_PREEMPT_RT:
>
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index f0d5b82e478d..257b170aacb6 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -1262,6 +1262,7 @@ config PROVE_LOCKING
> config PROVE_RAW_LOCK_NESTING
> bool "Enable raw_spinlock - spinlock nesting checks"
> depends on PROVE_LOCKING
> + depends on PREEMPT_RT
> default n
> help
> Enable the raw_spinlock vs. spinlock nesting checks which ensure

No, very much not. The idea is that we want to work towards having this
always enabled (when PROVE_LOCKING) to ensure code gets and stays
PREEMPT_RT clean.